# Endangered and Threatened Wildlife and Plants; Listing Seven Brazilian Bird Species as Endangered Throughout Their Range

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3AE9-18691

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** August 12, 2009
- **Citation:** 74 FR 40650

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R9-IA-2009-0028; 96100-1671-0000-B6]
RIN 1018-AV74
Endangered and Threatened Wildlife and Plants; Listing Seven Brazilian Bird Species as Endangered Throughout Their Range

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Proposed rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), propose to list the following seven Brazilian bird species and subspecies (collectively referred to as “species” for purposes of this proposed rule) as endangered under the Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531
et seq.
): black-hooded antwren (
Formicivora erythronotos
), Brazilian merganser (
Mergus octosetaceus
), cherry-throated tanager (
Nemosia rourei
), fringe-backed fire-eye (
Pyriglena atra
), Kaempfer's tody-tyrant (
Hemitriccus kaempferi
), Margaretta's hermit (
Phaethornis malaris margarettae
), and southeastern rufous-vented ground-cuckoo (
Neomorphus geoffroyi dulcis
). This proposal, if made final, would extend the Act's protection to these species. The Service seeks data and comments from the public on this proposed rule.

DATES:

We will accept comments received or postmarked on or before October 13, 2009. We must receive requests for public hearings, in writing, at the address shown in the
FOR FURTHER INFORMATION CONTACT
section by September 28, 2009.

ADDRESSES:

You may submit comments by one of the following methods:

•
Federal eRulemaking Portal: http://www.regulations.gov
. Follow the instructions for submitting comments.

•
U.S. mail or hand-delivery:
Public Comments Processing, Attn: FWS-R9-IA-2009-0028; Division of Policy and Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, Suite 222; Arlington, VA 22203.

We will post all comments on
http://www.regulations.gov
. This generally means that we will post any personal information you provide us (see the Public Comments section below for more information).

FOR FURTHER INFORMATION CONTACT:

Douglas Krofta, Chief, Branch of Listing, Endangered Species Program, U.S. Fish and Wildlife Service, 4401 N. Fairfax Drive, Room 420, Arlington, VA 22203; telephone 703-358-2105; facsimile 703-358-1735. If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments

We intend that any final action resulting from this proposal will be as accurate and as effective as possible. Therefore, we request comments or suggestions on this proposed rule. We particularly seek comments concerning:

(1) Biological, commercial trade, or other relevant data concerning any threats (or lack thereof) to these species and regulations that may be addressing those threats.

(2) Additional information concerning the taxonomy, range, distribution, and population size of these species, including the locations of any additional populations of these species.

(3) Any information on the biological or ecological requirements of these species.

(4) Current or planned activities in the areas occupied by these species and possible impacts of these activities on these species.

(5) Any information concerning the effects of climate change on these species or their habitats.

You may submit your comments and materials concerning this proposed rule by one of the methods listed in the
ADDRESSES
section. We will not consider comments sent by e-mail or fax or to an address not listed in the
ADDRESSES
section.

If you submit a comment via
http://www.regulations.gov,
your entire comment—including any personal identifying information—will be posted on the Web site. If you submit a hardcopy comment that includes personal identifying information, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so. We will post all hardcopy comments on
http://www.regulations.gov
.

Comments and materials we receive, as well as supporting documentation we used in preparing this proposed rule, will be available for public inspection on
http://www.regulations.gov
, or by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Endangered Species Program, 4401 N. Fairfax Drive, Room 420, Arlington, VA 22203; telephone 703-358-2171.

Background

Section 4(b)(3)(A) of the Act requires us to make a finding (known as a “90-day finding”) on whether a petition to add a species to, remove a species from, or reclassify a species on the Federal Lists of Endangered and Threatened Wildlife and Plants has presented substantial information indicating that the requested action may be warranted. To the maximum extent practicable, the finding must be made within 90 days following receipt of the petition and must be published promptly in the
Federal Register
. If we find that the petition has presented substantial information indicating that the requested action may be warranted (a positive finding), section 4(b)(3)(A) of the Act requires us to commence a status review of the species if one has not already been initiated under our internal candidate assessment process. In addition, section 4(b)(3)(B) of the Act requires us to make a finding within 12 months following receipt of the petition (“12-month finding”) on whether the requested action is warranted, not warranted, or warranted but precluded by higher priority listing. Section 4(b)(3)(C) of the Act requires that a finding of warranted but precluded for petitioned species should be treated as having been resubmitted on the date of the warranted but precluded finding, and is, therefore, subject to a new finding within 1 year and subsequently thereafter until we publish a proposal to list or a finding that the petitioned action is not warranted. The Service publishes an annual notice of resubmitted petition findings (annual notice) for all foreign species for which listings were previously found to be warranted but precluded.

The following seven Brazilian bird species are addressed in this proposed rule: Black-hooded antwren (
Formicivora erythronotos
), previously recognized under the genus
Myrmotherula
; Brazilian merganser (
Mergus octosetaceus
); cherry-throated tanager (
Nemosia rourei
); fringe-backed fire-eye (
Pyriglena atra
), previously referred to as Swainson's fire-eye; Kaempfer's tody-tyrant (
Hemitriccus kaempferi
), previously recognized under the genus
Idioptilon
; Margaretta's hermit (
Phaethornis malaris margarettae
), previously referred to as the Klabin Farm long-tailed hermit and recognized at the species level as
P. margarettae
; and southeastern rufous-vented ground-cuckoo (
Neomorphus geoffroyi dulcis
). All of the above species are found in the Atlantic Forest and neighboring regions of southeastern Brazil.

We are addressing the seven Brazilian bird species identified above under a single proposed rule primarily for three reasons. First, all of these species are found in the Atlantic Forest and neighboring regions of southeastern Brazil, thus addressing them together makes sense from a regional conservation perspective. Second, these seven species are subject to similar threats of comparable magnitude, primarily the loss and degradation of habitat due to deforestation and other ongoing development practices affecting southeastern Brazil, as well as concomitant threats due to severely restricted distributions and small population sizes (such as potential loss of genetic viability). Combining species that face similar threats within the same general geographic area into one proposed rule allows us to maximize our limited staff resources, thus increasing our ability to complete the listing process for warranted-but-precluded species.

Previous Federal Actions

On November 28, 1980, we received a petition (the 1980 petition) from Dr. Warren B. King, Chairman, United States Section of the International Council for Bird Preservation (ICBP), to add 60 foreign bird species to the List of Endangered and Threatened Wildlife (50 CFR 17.11(h)), including 5 of the 7 Brazilian bird species (black-hooded antwren, cherry-throated tanager, fringe-backed fire-eye, Margaretta's hermit, and southeastern rufous-vented ground-cuckoo) that are the subject of this proposed rule. Two of the foreign species identified in the petition were already listed under the Act; therefore, in response to the 1980 petition, we published a substantial 90-day finding on May 12, 1981 (46 FR 26464), for 58 foreign species and initiated a status review. On January 20, 1984 (49 FR 2485), we published a 12-month finding within an annual review on pending petitions and description of progress on all pending petition findings. In that notice, we found that all 58 foreign bird species from the 1980 petition were warranted but precluded by higher priority listing actions. On May 10, 1985, we published the first annual notice (50 FR 19761) in which we continued to find that listing all 58 foreign bird species from the 1980 petition was warranted but precluded. We published additional annual notices on the 58 species included in the 1980 petition on January 9, 1986 (51 FR 996), July 7, 1988 (53 FR 25511), December 29, 1988 (53 FR 52746), April 25, 1990 (55 FR 17475), November 21, 1991 (56 FR 58664), and May 21, 2004 (69 FR 29354). These notices indicated that the black-hooded antwren, cherry-throated tanager, fringe-backed fire-eye, Margaretta's hermit, and southeastern rufous-vented ground-cuckoo, along with the remaining species in the 1980 petition, continued to be warranted but precluded.

On May 6, 1991, we received a second petition (the 1991 petition) from ICBP to add an additional 53 foreign bird species to the List of Endangered and Threatened Wildlife, including the 2 remaining Brazilian bird species (Brazilian merganser and Kaempfer's tody-tyrant) that are the subject of this proposed rule. In response to the 1991 petition, we published a substantial 90-day finding on December 16, 1991 (56 FR 65207), for all 53 species and initiated a status review. On March 28, 1994 (59 FR 14496), we published a 12-month finding on the 1991 petition, along with a proposed rule to list 30 African birds under the Act (15 each from the 1980 petition and 1991 petition). In that document, we announced our finding that listing the remaining 38 species from the 1991 petition, including the Brazilian merganser and Kaempfer's tody-tyrant, was warranted but precluded by higher priority listing actions. We made a subsequent warranted-but-precluded finding for all outstanding foreign species from the 1980 and 1991 petitions, including the seven Brazilian bird species that are the subject of this proposed rule, as published in our annual notice of review (ANOR) on May 21, 2004 (69 FR 29354).

Per the Service's listing priority guidelines (September 21, 1983; 48 FR 43098), our 2007 ANOR identified the listing priority numbers (LPNs) (ranging from 1 to 12) for all outstanding foreign species. The LPNs for the seven Brazilian bird species that are the subject of this proposed rule are as follows: The black-hooded antwren, Brazilian merganser, cherry-throated tanager, fringe-backed fire-eye, and Kaempfer's tody-tyrant (LPN 2); and the Margaretta's hermit and southeastern rufous-vented ground-cuckoo (LPN 3). Listing priorities of 2 and 3 indicate that the subject species and subspecies, respectively, face imminent threats of high magnitude. With the exception of listing priority ranking of 1, which addresses monotypic genera that face imminent threats of high magnitude, categories 2 and 3 represent the Service's highest priorities.

On July 29, 2008 (73 FR 44062), we published in the
Federal Register
a notice announcing our annual petition findings for foreign species. In that notice, we announced listing to be warranted for 30 foreign bird species, including the seven Brazilian bird species which are the subject of this proposed rule, and stated that we would “promptly publish proposals to list these 30 taxa.”

On September 8, 2008, the Service received a 60-day notice of intent to sue from the Center for Biological Diversity (CBD) over violations of section 4 of the Act for the Service's failure to promptly publish listing proposals for the 30 “warranted” species identified in our 2008 ANOR. Under a settlement agreement approved by the U.S. District Court for the Northern District of California on June 15, 2009, (
CDB
v.
Salazar,
09-cv-02578-CRB), the Service must submit to the
Federal Register
proposed listing rules for the black-hooded antwren, Brazilian merganser, cherry-throated tanager, fringe-backed fire-eye, Kaempfer's tody-tyrant, Margaretta's hermit, and southeastern rufous-vented ground-cuckoo by July 31, 2009.

Species Information and Factors Affecting the Species

Section 4 of the Act (16 U.S.C. 1533), and its implementing regulations at 50 CFR part 424, set forth the procedures for adding species to the Federal Lists of Endangered and Threatened Wildlife and Plants. A species may be determined to be an endangered or threatened species due to one or more of the five factors described in section 4(a)(1) of the Act. The five factors are: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) the inadequacy of existing regulatory mechanisms; and (E) other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination.

If we consider that wildlife habitat is not only defined by substrates (vegetation, soil, water), but also atmospheric conditions, then changes in air temperature and moisture can effectively change a species' habitat. Climate change is characterized by variations in the earth's temperature and precipitation causing changes in atmospheric, oceanic, and terrestrial conditions (Parmesan and Mathews 2005, p. 334). Global climate change and other periodic climatic patterns (
e.g.
, El Niño and La Niña) can cause or exacerbate such negative impacts on a broad range of terrestrial ecosystems and neotropical bird populations (Crick 2004, p. 1; England 2000, p. 86;

Holmgren
et al.
2001, p. 89; Plumart 2007, pp. 1-2). For example, trees cool their area of influence through high rates of evapotranspiration, or water loss to the atmosphere from their leaves (Parmesan and Mathews 2005, p. 337). Areas where trees have been replaced with pastures have lower evapotranspiration rates, thus causing local areas to be warmer (Parmesan and Mathews 2005, p. 337). According to the Intergovernmental Panel on Climate Change (IPCC), climate change can contribute to modifications of Amazonian rainforest habitats that are affected by deforestation (IPCC 1997, p. 11). Parmesan and Mathews (2005, p. 373) suggest that climate change is more likely to cause range reductions rather than range shifts. This may be due to the lack of areas where a species could shift to or the spaces between habitat patches are too large for individuals to reach. This suggests that climate change could be an agent of habitat loss or modification.

Despite the fact that global climate changes are occurring and affecting habitat, the climate change models that are currently available are not yet able to make meaningful predictions of climate change for specific, local areas (Parmesan and Matthews 2005, p. 354), such as the Atlantic Forest and Cerrado (savanna) bioregions. In addition, we do not have models to predict how the climate in the range of these Brazilian bird species will change, and we do not know how any change that may occur, would affect these species. We also do not have information on past and future weather patterns within the specific range of these species. Therefore, based on the current lack of information and data, we did not evaluate climate change as a threat to these species. We are, however, seeking additional information on this subject (see Public Comments) that can be used in preparing the final rule.

Below is a species-by-species analysis of the five factors. The species are considered in alphabetical order, beginning with the black-hooded antwren, followed by the Brazilian merganser, cherry-throated tanager, fringe-backed fire-eye, Kaempfer's tody-tyrant, Margaretta's hermit, and the southeastern rufous-vented ground-cuckoo.

I. Black-hooded Antwren (Formicivora erythronotos)

Species Description

The black-hooded antwren measures 10.5 to 11.5 centimeters (cm) (4 to 4.5 inches (in)) (BirdLife International (BLI) 2007d, p. 1; Sisk 1993, p. 414). Males are black with a reddish-brown back. They have a black narrow bill and a long tail. There are three thin white stripes on the wings. Females have similar coloring, except they have brown-olive feathers where black feathers appear on males (BLI 2007d, p. 1).

Taxonomy

The black-hooded antwren is a small member of the diverse “antbird” family (Thamnophilidae). The species was previously recognized under the genus
Myrmotherula
(BLI 2007d, p. 1; Collar
et al.
1992, p. 667; Sick 1993, p. 414).

Habitat and Life History

The Atlantic Forest biome encompasses a region of tropical and subtropical moist forests, tropical dry forests, and mangrove forests, that extend along the Atlantic coast of Brazil from Rio Grande do Norte in the north to Rio Grande do Sul in the south, and inland as far as Paraguay and Misiones Province of northeastern Argentina (Conservation International 2007a, p. 1; Höfling 2007, p. 1; Morellato and Haddad 2000, pp. 786-787). The black-hooded antwren inhabits lush understories of remnant old-growth and early successional secondary-growth coastal forests, and it may also occur in dense understories of modified “restinga,” (“restinga” is a Brazilian term that describes a patchwork of vegetation types consisting of beach vegetation, open shrubby vegetation, and dry and swamp forests distributed over coastal plains from northeastern to southeastern Brazil (McGinley 2007, pp. 1-2)), swampy woodlands, abandoned banana plantations, and eucalyptus stands (BLI 2007d, p. 1; Tobias and Williams 1996, p. 64).

Although the specific habitat requirements of the black-hooded antwren are still unclear, the species is not considered a tropical forest specialist. The black-hooded antwren typically forages in pairs or small family groups and consumes various insects, spiders, and small frogs (Collar
et al.
1992, p. 667; del Hoyo 2003, p. 616; Sick 1993, p. 405; Tobias and Williams 1996, p. 65). Black-hooded antwrens usually forage in dense vegetation within approximately 3 meters (m) (10 feet (ft)) of the ground, but they are also known to feed higher up (ca. 7 m (23 ft)).

Females typically lay two eggs in fragile nests resembling small cups made of plant material (
e.g.
, rootlets, stems, moss) that are attached to horizontal branches within roughly 1 m (3.3 ft) of the ground (Collar
et al.
1992, p. 667; Sick 1993, p. 405). Both sexes help to build the nests, brood clutches, and attend their young.

Range and Distribution

The black-hooded antwren is endemic to the Atlantic Forest biome in the southeast of the state of Rio de Janeiro (BLI 2007d, p. 1; Collar
et al.
1992, p. 667). Currently, the only confirmed population is believed to be restricted to remnant patches of forest habitat along roughly 30 kilometers (km) (19 miles (mi)) of coast in southern Rio de Janeiro, near the border with São Paulo (Browne 2005, p. 95; Tobias and Williams 1996, p. 64). However, there have also been recent unconfirmed reports that the species may occur at the state Ecological Reserve of Jacarepiá, located roughly 75 km (47 mi) northeast of the city of Rio de Janeiro (ADEJA 2007, p. 3; WorldTwitch 2007, p. 12).

Population Estimates

The black-hooded antwren was known from 20 specimens that were purportedly collected in the 1800s in montane forest habitats of central Rio de Janeiro, Brazil. The species had not been reported since that collection until it was rediscovered in 1987 in the Atlantic forest in south Rio de Janeiro (BLI 2007d, p. 1).

The extant population is estimated to be between 1,000 and 2,499 birds, and is fragmented among seven occupied sites, including Bracuí, Frade, São Gonçalo, Taquari and Barra Grande, Ariró, and Vale do Mambucaba. Vale do Mambucaba has the highest known density of pairs (156 pairs per square kilometer (km
2
)), followed by Mambucaba (densities of 89 pairs/km
2
). There are no known estimates for the other locations, but it is believed that the numbers are few (BLI 2007d, p. 1). At least one of the fragmented populations is believed to be reproductively isolated. The population, as a whole, is also believed to be declining rapidly due to continued loss of habitat (BLI 2007d, pp. 1-3).

Conservation Status

The IUCN considers the black-hooded antwren to be “Endangered” because “it has a very small and severely fragmented range that is likely to be declining rapidly in response to habitat loss” (BLI 2007d, p. 3). The species is also protected by Brazilian law and occurs in the buffer area of Serra da Bocaína National Park (BLI 2007d, p. 2).

Summary of Factors Affecting the Black-hooded Antwren

A. The Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range

Based on a number of recent estimates, 92 to 95 percent of the area historically covered by tropical forests within the Atlantic Forest biome has been converted or severely degraded as a result of various human activities (Butler 2007, p. 2; Conservation International 2007a, p. 1; Höfling 2007, p. 1; Morellato and Haddad 2000, p. 786; Myers
et al.
2000, pp. 853-854; The Nature Conservancy 2007, p. 1; Saatchi
et al.
2001, p. 868; World Wildlife Fund 2007, pp. 2-41). In addition to the overall loss and degradation of native habitats within this biome, the remaining tracts of habitat are severely fragmented. The current rate of habitat decline is unknown.

The region has the two largest cities in Brazil, São Paulo and Rio de Janeiro, and is home to approximately 70 percent of Brazil's 169 million people (CEPF 2002; IBGE 2007). The major human activities that have resulted in the loss, degradation, and fragmentation of native habitats within the Atlantic Forest biome include extensive establishment of agricultural fields (
e.g.
, soy beans, sugarcane, corn), plantations (
e.g.
, eucalyptus, pine, coffee, cocoa, rubber, bananas), livestock pastures, centers of human habitation, and industrial developments (
e.g.
, charcoal production, steel plants, hydropower reservoirs). Forestry practices (
e.g.
, commercial logging, subsistence activities, fuelwood collection) and changes in fire frequencies (BLI 2003a, p. 4; Júnior
et al.
1995, p. 147; The Nature Conservancy 2007, p. 2; Nunes and Kraas 2000, p. 44; Peixoto and Silva 2007, p. 5; Saatchi
et al.
2001, pp. 868-869; Scott and Brooke 1985, p. 118; World Wildlife Fund 2007, pp. 3-51) also contribute to the degradation of native habitat.

The black-hooded antwren is not strictly tied to primary forest habitats and can make use of secondary-growth forests or other disturbed areas, such as modified “restinga,” eucalyptus stands, abandoned banana plantations, and recently burned sites (BLI 2007d, p. 1; Tobias and Williams 1996, p. 64). However, this does not necessarily lessen the threat to the species from the effects of deforestation and habitat degradation. Atlantic Forest birds, such as the black-hooded antwren, which are tolerant of secondary-growth forests or other disturbed sites, are also rare or have severely restricted ranges (
i.e.
, less than 21,000 km
2
(8,100 square miles (mi
2
))). Thus habitat degradation can adversely impact such species, just as equally as it impacts primary forest-obligate species (Harris and Pimm 2004, pp. 1612-1613). While the black-hooded antwren is relatively abundant locally, the entire range of the species encompasses only about 130 km
2
(50 mi
2
), with only 45 percent of this area considered occupied (BLI 2007d, pp. 3-4).

The susceptibility to habitat destruction of limited-range species that are tolerant of secondary-growth forests or other disturbed sites can occur for a variety of reasons, such as when a species' remaining population is already too small or its distribution too fragmented such that it may not be demographically or genetically viable (Harris and Pimm 2004, pp. 1612-1613). In addition, while the black-hooded antwren may be tolerant of secondary-growth forests or other disturbed sites, these areas may not represent optimal conditions for the species, which would include dense understories and abundant prey species. For example, management of plantations often involves intensive control of the site's understory vegetation and long-term use of pesticides, which eventually results in severely diminished understory cover and potential prey species (Rolim and Chiarello 2004, pp. 2687-2691; Saatchi
et al.
2001, pp. 868-869; Scott and Brooke 1985, p. 118). Such management activities make these sites unsuitable for the black-hooded antwren (BLI 2007d, p. 2).

Impacts associated with the destruction of native habitat by human activities within the Atlantic Forest biome include extensive fragmentation of the remaining tracts of forested habitat potentially used by the black-hooded antwren (see Factor E). As a secondary impact, habitat destruction of these remaining tracts increases the potential introduction of disease vectors or exotic predators within the species' historic range (see Factor C). Furthermore, even when potentially occupied sites may be formally protected, such as the state Ecological Reserve of Jacarepiá (see Factor D), the remaining fragments of forested habitat will likely undergo further degradation due to their altered dynamics and isolation (ADEJA 2007, pp. 1-2; Tabanez and Viana 2000, pp. 929-932). Altered dynamics and isolation are characterized by a decrease in gene flow and inbreeding, which decrease the fitness of forest species (Tabanez and Viana 2000, pp. 929-932). In addition, fragmented Atlantic forests of Brazil are observed to be overtaken by lianas (long-stemmed woody vines), which cause tree falls and gaps in the forest structure. These gaps in the forest encourage gap-opportunistic vegetation to grow. Hence, a decrease in gene flow, and increases in inbreeding, liana density, and presence of gap-opportunistic species change the character and dynamics of the Atlantic Forest biome and isolate fragmented habitat patches (Tabanez and Viana 2000, pp. 930-931). These changes may result in the loss of important species that comprise the black-hooded antwren habitat. As a result of these secondary impacts, there is often a time lag between the initial conversion or degradation of suitable habitats and the extinction of endemic bird populations (Brooks
et al.
1999a, p. 1; Brooks
et al.
1999b, p. 1140). Therefore, even without further habitat loss or degradation, the black-hooded antwren remains at risk from past impacts to its suitable habitats.

The black-hooded antwren occurs in one of the most densely populated regions of Brazil, and most of the tropical forest habitats believed to have been used historically by the species have been converted or are severely degraded due to the wide range of human activities identified above (BLI 2003a, p. 4; BLI 2007d, p. 2; Collar
et al.
1992, p. 667; Conservation International 2007a, p. 1; del Hoyo 2003, p. 616; Höfling 2007, p. 1; The Nature Conservancy 2007, p. 1; World Wildlife Fund 2007, pp. 3-51). In addition, the remaining tracts of suitable habitat in Rio de Janeiro and São Paulo are threatened by ongoing development of coastal areas, primarily for tourism enterprises (
e.g.
, large hotel complexes, beachside housing) and associated infrastructure support, as well as widespread clearing for expansion of livestock pastures and plantations, primarily for
Euterpe
palms (BLI 2003a, p. 4; BLI 2007d, p. 2; Collar
et al.
1992, p. 667; del Hoyo 2003, p. 616; World Wildlife Fund 2007, pp. 7 and 36-37). These impacts have recently reduced suitable habitats at various key sites known to be occupied by the black-hooded antwren such as Vale do Mambucaba and Ariró, and the remaining occupied habitats at these sites are subject to ongoing human disturbances, such as off-road vehicle use, burning, and recreational activities (BLI 2007d, p. 2; Collar
et al.
1994, p. 134; del Hoyo 2003, p. 616).

Summary of Factor A

A significant portion of Atlantic Forest habitats have been, and continue to be, lost and degraded by various ongoing human activities, including

logging, establishment and expansion of plantations and livestock pastures, urban and industrial developments (including many new hydroelectric dams), slash-and-burn clearing, intentional and accidental ignition of fires, and establishment of invasive species (CEPF 2001, pp. 9-15). Even with the recent passage of a national forest policy and in light of many other legal protections in Brazil (see Factor D), the rate of habitat loss throughout the Atlantic Forest biome has increased since the mid-1990s (CEPF 2001, p. 10; Hodge
et al.
1997, p. 1; Rocha
et al.
2005, p. 270), and native habitats at many of the remaining sites may be lost over the next several years (Rocha
et al.
2005, p. 263). Furthermore, because the black-hooded antwren's extant population is already small, highly fragmented, and believed to be declining (BLI 2007d, pp. 1-3), any further loss or degradation of its remaining suitable habitat represents a significant threat to the species (see Factor E). Therefore, we find that destruction and modification of habitat are threats to the continued existence of the black-hooded antwren throughout its range.

B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

The extant population of the black-hooded antwren is considered to be small, fragmented, and declining. The species was deliberately not collected when it was rediscovered in 1987 (Collar
et al.
1992, p. 667). This is because the removal or dispersal of just a few individuals from any of the black-hooded antwren's subpopulations or even a slight decline in their fitness due to intentional or inadvertent hunting, specimen collection, or other human disturbances (
e.g.
, scientific research, birding) could represent significant risks to the species' overall viability (see Factor E). However, while these potential influences remain a concern for future management of the species, we are not aware of any other information currently available that indicates the use of this species for any commercial, recreational, scientific, or educational purpose. As a result, we are not considering overutilization to be a contributing factor to the continued existence of the black-hooded antwren.

C. Disease or Predation

Large, stable populations of wildlife species have adapted to natural levels of disease and predation within their historic ranges. However, the extant population of the black-hooded antwren is considered to be small, fragmented, and declining. In addition, extensive human activity in previously undisturbed or isolated areas can lead to the introduction and spread of exotic diseases, some of which (
e.g.
, West Nile virus) can negatively impact endemic bird populations (Naugle
et al.
2004, p. 704; Neotropical News 2003, p. 1). Extensive human activity in previously undisturbed or isolated areas can also result in altered predator populations and the introduction of various exotic predator species, some of which (
e.g.
, feral cats (
Felis catus
) and rats (
Ratus
sp.)) can be especially harmful to populations of endemic bird species (American Bird Conservancy 2007, p. 1; Courchamp
et al.
1999, p. 219; Duncan and Blackburn 2007, pp. 149-150; Salo
et al.
2007, pp. 1241-1242; Small 2005, p. 257). Any additive mortality to the black-hooded antwren's subpopulations or a decrease in their fitness due to an increase in the incidence of disease or predation could represent significant threats to the species' overall viability (see Factor E).

Although disease and predation may be a concern for future management of the black-hooded antwren, we are not aware of any species-specific information currently available that indicates that disease or predation poses a threat to the species. As a result, we are not considering disease or predation to be a contributing factor to the continued existence of the black-hooded antwren.

D. The Inadequacy of Existing Regulatory Mechanisms

The black-hooded antwren is formally recognized as “endangered” in Brazil (Order No. 1.522) and is directly protected by various laws promulgated by the Brazilian government (BLI 2007d, p. 2; Collar
et al.
1992, p. 667; ECOLEX 2007, pp. 1-2). For example, there are measures that prohibit, or regulate through Federal agency oversight, the following activities with regard to endangered species: export and international trade (
e.g.
, Decree No. 76.623, Order No. 419-P), hunting (
e.g.
, Act No. 5.197), collection and research (Order No. 332), captive propagation (Order No. 5), and general harm (
e.g.
, Decree No. 3.179). In addition, there are a wide range of regulatory mechanisms in Brazil that indirectly protect the black-hooded antwren through measures that protect its remaining suitable habitat (ECOLEX 2007, pp. 2-5). For example, there are measures that: (1) Prohibit exploitation of the remaining primary forests within the Atlantic Forest biome (
e.g.
, Decree No. 750, Resolution No. 10); (2) govern various practices associated with the management of primary and secondary forests, such as logging, charcoal production, reforestation, recreation, and water resources (
e.g.
, Resolution No. 9, Act No. 4.771, Decree No. 1.282, Decree No. 3.420, Order No. 74-N, Act No. 7.803); (3) establish provisions for controlling forest fires (
e.g.
, Decree No. 97.635, Order No. 231-P, Order No. 292-P, Decree No. 2.661); and (4) regulate industrial developments, such as hydroelectric plants and biodiesel production (
e.g.
, Normative Instruction No. 65, Law No. 11.116). Finally, there are various measures (
e.g.
, Law No. 11.516, Act No. 7.735, Decree No. 78, Order No. 1, Act No. 6.938) that direct Federal and state agencies to promote the protection of lands and natural resources under their jurisdictions (ECOLEX 2007, pp. 5-6).

There are also various regulatory mechanisms in Brazil that govern the formal establishment and management of protected areas to promote conservation of the country's natural resources (ECOLEX 2007, pp. 6-7). These mechanisms generally aim to protect endangered wildlife and plant species, genetic resources, overall biodiversity, and native ecosystems on Federal, state, and privately owned lands (
e.g.
, Law No. 9.985, Law No. 11.132, Resolution No. 4, Decree No. 1.922). Brazil's formally established protection areas are categorized based on their overall management objectives (
e.g.
, National Parks versus Biological Reserves); and based on those categories, they allow varying uses and provide varying levels of protection for specific resources (Costa 2007, pp. 5-19).

The black-hooded antwren occurs in the buffer zone around Serra da Bocaina National Park and, possibly, within Tamoios Environmental Protection Area and the Ecological Reserve of Jacarepiá (BLI 2007d, p. 2; del Hoyo 2003, p. 616; WorldTwitch 2007, p. 12). It has been recommended that some of these sites should be expanded and other sites designated to ensure the species' currently occupied range is encompassed within protected areas. However, for various reasons (
e.g.
, lack of funding, personnel, or local management commitment), some of Brazil's protected areas exist without the current capacity to achieve their stated natural resource objectives (ADEJA 2007, pp. 1-2; Bruner
et al.
2001, p. 125; Costa 2007, p. 7; IUCN 1999, pp. 23-24; Neotropical News 1996, pp. 9-10; Neotropical News 1999, p. 9). Therefore, even with the expansion or further designation of protected areas, it is likely that not all of the identified resource concerns for

the black-hooded antwren (
e.g.
, residential and agricultural encroachment, resource extraction, unregulated tourism, grazing) would be sufficiently addressed at these sites.

In the past, the Brazilian government, through various regulations, policies, incentives, and subsidies, has actively encouraged settlement of previously undeveloped lands in southeastern Brazil, which helped facilitate the large-scale habitat conversions that have occurred throughout the Atlantic Forest biome (Brannstrom 2000, p. 326; Butler 2007, p. 3; Conservation International 2007c, p. 1; Pivello 2007, p. 2; Ratter
et al.
1997, pp. 227-228; Saatchi
et al.
2001, p. 874). More recently, the Brazilian government has given greater recognition to the environmental consequences of such rapid expansion, and has taken steps to better manage some of the natural resources potentially impacted (Butler 2007, p. 7; Costa 2007, p. 7; Neotropical News 1997a, p. 10; Neotropical News 1997b, p. 11; Neotropical News 1998b, p. 9; Neotropical News 2003, p. 13; Nunes and Kraas 2000, p. 45). Despite these efforts, pressures to develop coastal areas containing black-hooded antwren habitat for tourism (
e.g.
, large hotel complexes, beachside housing) and plantation agriculture continue to be a threat to the species (ADEJA 2007, pp. 1-2; BLI 2007d, p. 2; Tobias and Williams 1996, p. 65).

Summary of Factor D

Brazil's wide variety of laws requiring resource protection that would ultimately benefit the black-hooded antwren are tested by the intense development pressure that exists in coastal areas south of Rio de Janeiro. Despite the existence of these regulatory mechanisms, habitat loss throughout the Atlantic Forest biome has increased for more than a decade. The existing regulatory mechanisms have proven difficult to enforce (BLI 2003a, p. 4; Conservation International 2007c, p. 1; Costa 2007, p. 7; The Nature Conservancy 2007, p. 2; Neotropical News 1997b, p. 11; Peixoto and Silva 2007, p. 5; Scott and Brooke 1985, pp. 118, 130). As a result, threats to the black-hooded antwren's remaining habitat are ongoing (see Factor A) due to the challenges that Brazil faces to balance its competing development and environmental priorities. Therefore, when combined with Factors A and E, we find that the existing regulatory mechanisms are inadequate to ameliorate the current threats to the black-hooded antwren throughout its range.

E. Other Natural or Manmade Factors Affecting the Continued Existence of the Species

Under this factor we explore whether three risks, represented by demographic, genetic, and environmental stochastic events, are substantive to threaten the continued existence of the black-hooded antwren. In basic terms, demographic stochasticity is defined by chance changes in the population growth rate for the species (Gilpin and Soulé 1986, p. 27). Population growth rates are influenced by individual birth and death rates (Gilpin and Soulé 1986, p. 27), immigration and emigration rates, as well as changes in population sex ratios. Natural variation in survival and reproductive success of individuals and chance disequilibrium of sex ratios may act in concert to contribute to demographic stochasticity (Gilpin and Soulé 1986, p. 27). Genetic stochasticity is caused by changes in gene frequencies due to genetic drift, and diminished genetic diversity, and/or effects due to inbreeding (
i.e.
, inbreeding depression) (Lande 1995, p. 786). Inbreeding can have individual or population-level consequences either by increasing the phenotypic expression (the outward appearance, or observable structure, function, or behavior of a living organism) of recessive, deleterious alleles or by reducing the overall fitness of individuals in the population (Charlesworth and Charlesworth 1987, p. 231; Shaffer 1981, p. 131). Environmental stochasticity is defined as the susceptibility of small, isolated populations of wildlife species to natural levels of environmental variability and related “catastrophic” events (
e.g.
, severe storms, prolonged drought, extreme cold spells, wildfire) (Dunham
et al.
1999, p. 9; Mangel and Tier 1994, p. 612; Young 1994, pp. 410-412). Each risk will be analyzed specifically for the black-hooded antwren.

Small, isolated populations of wildlife species are susceptible to demographic and genetic problems (Shaffer 1981, pp. 130-134). These threat factors, which may act in concert, include: natural variation in survival and reproductive success of individuals, chance disequilibrium of sex ratios, changes in gene frequencies due to genetic drift, diminished genetic diversity and associated effects due to inbreeding (
i.e.
, inbreeding depression), dispersal of just a few individuals, a few clutch failures, a skewed sex ratio in recruited offspring over just one or a few years, and chance mortality of just a few reproductive-age individuals.

There is very little information available regarding the historic distribution and abundance of the black-hooded antwren. However, the species' historic population was likely larger and more widely distributed than today, and it must have maintained a minimum level of genetic interchange among its local subpopulations in order for them to have persisted (Middleton and Nisbet 1997, p. 107; Vilà
et al.
2002, p. 91; Wang 2004, p. 332). The available information indicates that suitable habitats currently occupied by the black-hooded antwren are highly fragmented and that the species' extant population is small and declining (BLI 2007d, pp. 1-3). Without efforts to maintain buffer areas and reconnect some of the remaining tracts of suitable habitat near the species' currently occupied sites, it is doubtful that the individual tracts are currently large enough to support viable populations of many birds endemic to the Atlantic Forest, like the black-hooded antwren, and the eventual loss of any small, isolated populations appears to be inevitable (Goerck 1997, p. 117; Harris and Pimm 2004, pp. 1609-1610; IUCN 1999, pp. 23-24; Machado and Da Fonseca 2000, pp. 914, 921-922; Saatchi
et al.
2001, p. 873; Scott and Brooke 1985, p. 118).

Various past and ongoing human activities and their secondary influences continue to impact all of the remaining suitable habitats that may still harbor the black-hooded antwren (see Factors A and D). We expect that any additional loss or degradation of habitats that are used by the black-hooded antwren will have disproportionately greater impacts on the species due to the population's fragmented state. This is because with each contraction of an existing subpopulation, the likelihood of interchange with other subpopulations within patches decreases, while the likelihood of its complete reproductive isolation increases.

The combined effects of habitat fragmentation (Factor A) and genetic and demographic stochasticity on a species population are referred to as patch dynamics. Patch dynamics can have profound effects on fragmented subpopulations and can potentially reduce a species' respective effective population by orders of magnitude (Gilpin and Soulé 1986, p. 31). For example, an increase in habitat fragmentation can separate subpopulations to the point where individuals can no longer disperse and breed among habitat patches, causing a shift in the demographic characteristics of a population and a reduction in genetic fitness (Gilpin and Soulé 1986,

p. 31). Furthermore, as a species' status continues to decline, often as a result of deterministic forces such as habitat loss or overutilization, it will become increasingly vulnerable to a broad array of other forces. If this trend continues, its ultimate extinction due to one or more stochastic events becomes more likely.

We expect that the black-hooded antwren's increased vulnerability to demographic stochasticity and inbreeding will be operative even in the absence of any human-induced threats or stochastic environmental events, which only act to further exacerbate the species' vulnerability to local extirpations and eventual extinction. Demographic and genetic stochastic forces typically operate synergistically. Initial effects of one threat factor can later exacerbate the effects of other threat factors, as well as itself (Gilpin and Soulé 1986, pp. 25-26). For example, any further fragmentation of the populations will, by definition, result in the further removal or dispersal of individuals, which will exacerbate the other threats. Conversely, lack of a sufficient number of individuals in a local area or a decline in their individual or collective fitness may cause a decline in the population size, despite the presence of suitable habitat patches.

Small, isolated populations of wildlife species, such as the black-hooded antwren, are also susceptible to natural levels of environmental variability and related “catastrophic” events (
e.g.
, severe storms, prolonged drought, extreme cold spells, wildfire), which we will refer to as environmental stochasticity (Dunham
et al.
1999, p. 9; Mangel and Tier 1994, p. 612; Young 1994, pp. 410-412). A single stochastic environmental event can severely reduce existing wildlife populations and, if the affected population is already small or severely fragmented, it is likely that demographic stochasticity or inbreeding will become operative, which would place the population in jeopardy (Gilpin and Soulé 1986, p. 27; Lande 1995, pp. 787-789).

Summary of Factor E

The small and declining numbers that make up the black-hooded antwren's population makes it susceptible to natural environmental variability or chance events. In addition to its declining numbers, the high level of population fragmentation makes the species susceptible to genetic and demographic stochasticity. Therefore, we find that demographic, genetic, and environmental stochastic events are a threat to the continued existence of the black-hooded antwren throughout its range.

Status Determination for the Black-hooded Antwren

We have carefully assessed the best available scientific and commercial information regarding the past, present, and potential future threats faced by the black-hooded antwren. The species is currently at risk throughout all of its range due to ongoing threats of habitat destruction and modification (Factor A), and demographic, genetic, and environmental stochastic events associated with the species' high level of population fragmentation (Factor E). Furthermore, we have determined that the existing regulatory mechanisms (Factor D) are not adequate to ameliorate the current threats to the species.

Section 3 of the Act defines an “endangered species” as “any species which is in danger of extinction throughout all or a significant portion of its range” and a “threatened species” as “any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” Based on the threats to the black-hooded antwren throughout its entire range, as described above, we determine that the black-hooded antwren is in danger of extinction throughout all of its range. Therefore, on the basis of the best available scientific and commercial information, we are proposing to list the black-hooded antwren as an endangered species throughout all of its range.

II. Brazilian Merganser (Mergus Octosetaceus)

Species Description

The 49-56 cm (19-22 in) (BLI 2007a, p. 1) Brazilian merganser is described as resembling a cormorant (Sisk 1993, p. 163). The bird has a white wing speculum and red feet. The breast is pale grey with dark markings, and there is dark grey coloring in the upper breast (BLI 2007a, p. 1). The species has a distinctive green crest that extends over the nape of the neck (more developed in the male) (Sisk 1993, p. 163).

Taxonomy

The Brazilian merganser was first described by Vieillot in 1817 (Partridge 1956, p. 473). The species belongs in the family Anatidae (BLI 2007a, p. 1).

Habitat and Life History

The Brazilian merganser is highly adapted to shallow, rapid, clear-water streams and rivers, typically bordered by dense, tropical forest (Bruno
et al.
2006, p. 26; Collar
et al.
1992, pp. 80-86; Ducks Unlimited 2007, p. 1; Hughes
et al.
2006, p. 23; Partridge 1956, pp. 478-480; Sibley and Monroe 1990, p. 41). Where suitable riverine conditions exist, the Brazilian merganser also occurs in the Cerrado biome, which is characterized by open tropical savannah and comparatively sparse “gallery” forest at the river margins, indicating that the species is not strictly tied to tropical forest habitats (Bianchi
et al.
2005, p. 73; Braz
et al.
2003, p. 70).

Brazilian mergansers are strong swimmers and divers. They typically feed in river rapids or in pools adjacent to waterfalls, whereas they rest and perch in more slack water areas or at the river edges (Braz
et al.
2003, p. 70; Hughes
et al.
2006, p. 21; Partridge 1956, pp. 481-482). Brazilian mergansers feed primarily on a variety of fish species, with sizes up to approximately 19 cm (7.5 in), and occasionally on insects, snails, and other aquatic macro-invertebrates (Hughes
et al.
2006, p. 32; Partridge 1956, p. 483).

Brazilian mergansers are believed to be monogamous and sedentary. Breeding pairs appear to maintain their territories along a stretch of river (up to ca. 12 km (7.5 mi)) throughout the year (Braz
et al.
2003, p. 70; Ducks Unlimited 2007, p. 1; Hughes
et al.
2006, pp. 23, 33; Partridge 1956, p. 477). The breeding season begins in June and young hatch around August (Partridge 1956, p. 487). Females establish their nests relatively high up (25 m (82 ft)) in the cavities of tall trees that overlook the river and incubate their eggs alone, although males are attentive and remain nearby feeding and perching at the river shoreline (Bruno
et al.
2006, p. 29; Lamas and Santos 2004, p. 38; Partridge 1956, pp. 484-485). Females may also locate their nests lower down (10 m (33 ft)) in the cavities of cliffs or rocky outcrops near preferred riverine habitat in areas where suitable nesting trees are absent (Lamas and Santos 2004, pp. 38-39).

Range and Distribution

The Brazilian merganser occurs in a few fragmented locations in south-central Brazil, including the upper-tributaries of rivers within the Atlantic Forest biome and to the east in the Cerrado (savanna) biome (BLI 2007a, p. 1). The species is a diving duck that occurred historically in riverine habitats throughout southeastern Brazil, northeastern Argentina, and eastern Paraguay (Hughes
et al.
2006, p. 24). Currently, the species is found in extremely low numbers at six highly disjunct localities, of which five are in southeastern Brazil and one is in northeastern Argentina and, possibly,

extreme eastern Paraguay (BLI 2007a, pp. 1-5; Hughes
et al.
2006, pp. 28-31). The vast majority of the species' extant population and remaining suitable habitats occur in Brazil, including its largest subpopulation that is estimated to contain fewer than 50 individuals (BLI 2007a, p. 5).

The Brazilian merganser is thought to have been extirpated from Mato Grosso do Sul, São Paolo, Rio de Janeiro, and Santa Catarina (BLI 2007a, pp. 1-2). There is only a single recent record of the Brazilian merganser (ca. 2002) in the province of Misiones, Argentina, while the last confirmed sighting of the species in Paraguay is from 1984 (BLI 2007a, p. 2; Hughes
et al.
2006, p. 31). For purposes of this proposed rule, our analysis will focus on the most current estimates of the species, which are based in Brazil.

The species likely still occurs in the Brazilian states of Tocantins, Bahia, Goiás, Minas Gerais, and Paraná (Hughes
et al.
2006, pp. 51-52). Along with other recent sightings of the species in previously undocumented areas of Brazil (Bianchi
et al.
2005, p. 72; Pineschi 1999, p. 1), this information indicates that the Brazilian merganser may be more abundant and widespread than previously considered.

Population Estimates

The extant population is estimated to be between 50 and 249 individuals and is presumed to be declining, as evidenced by the species' recent history of extirpation from major portions of its historic range (BLI 2007a, p. 1).

Conservation Status

IUCN considers the Brazilian merganser to be “Critically Endangered” because “although recent records from Brazil, and particularly a recent northerly range extension, indicate that this species' status is better than previously thought, the remaining population is still extremely small and severely fragmented, and the perturbation and pollution of rivers continues to cause declines” (BLI 2007a, p. 1). In addition, the species occurs in three parks in Brazil and in the Uruguaí Provincial Park in Argentina (BLI 2007a, p. 1).

Summary of Factors Affecting the Brazilian Merganser

A. The Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range

Based on a number of recent estimates, 92 to 95 percent of the area historically covered by tropical forests within the Atlantic Forest biome has been converted or severely degraded as a result of various human activities (Conservation International 2007a, p. 1; Höfling 2007, p. 1; Morellato and Haddad 2000, p. 786; Myers
et al.
2000, pp. 853-854; The Nature Conservancy 2007, p. 1; Saatchi
et al.
2001, p. 868; World Wildlife Fund 2007, pp. 2-41). The Cerrado biome has also been heavily impacted by human activities, and current estimates indicate that between 67 and 80 percent of the tropical savannah habitat historically comprising this biome has been converted or severely degraded (Butler 2007, p. 1; Conservation International 2007b, p. 1; Mantovani and Pereira 1998, p. 1455; Myers
et al.
2000, p. 854; World Wildlife Fund 2007, p. 50). In addition to the overall loss and degradation of native habitat within these biomes, the remaining tracts of habitat are severely fragmented. The current rate of habitat loss in the Atlantic Forest and Cerrado biomes is unknown.

The region has the two largest cities in Brazil, São Paulo and Rio de Janeiro, and is home to approximately 70 percent of Brazil's 169 million people (CEPF 2002; IBGE 2007). The major human activities that have resulted in the loss, degradation, and fragmentation of native habitats within these biomes include extensive establishment of agricultural fields (
e.g.,
soy beans, sugarcane, and corn), plantations (
e.g.,
eucalyptus, pine, coffee, cocoa, rubber, and bananas), livestock pastures, centers of human habitation, and industrial developments (
e.g.,
diamond mining, hydropower reservoirs, and charcoal production). Forestry practices (
e.g.,
commercial logging), subsistence activities (
e.g.,
collection of fuelwood), and changes in fire frequencies also contribute to the degradation of native habitat (BLI 2003a, p. 4; BLI 2003b, pp. 1-2; Butler 2007, p. 1; Hughes
et al.
2006, pp. 37-48; Júnior
et al.
1995, p. 147; Nunes and Kraas 2000, p. 44; Pivello 2007, pp. 1-2; Ratter
et al.
1997, pp. 227-228; Saatchi
et al.
2001, pp. 868-869; World Food Prize 2007, pp. 1-5; World Wildlife Fund 2007, pp. 3-51).

The Brazilian merganser is extremely susceptible to habitat loss and degradation, habitat fragmentation, and hydrological changes from human activity (Collar
et al.
1992, pp. 83-84; Hughes
et al.
2006, pp. 36-41; Silveira 1998, p. 58). The loss of appropriate aquatic and terrestrial habitats throughout the historic range of the Brazilian merganser due to the above human activities is believed to have drastically reduced the species' abundance and extent of occupied range, and these activities currently represent a significant risk to the species' continued existence because populations are being limited to highly fragmented patches of habitat (Benstead 1994, p. 8; Benstead
et al.
1994, p. 36; BLI 2007a, pp. 1-6; Collar and Andrew 1988, p. 21; Collar
et al.
1992, pp. 83-84; Collar
et al.
1994, p. 51; Hughes
et al.
2006, pp. 37-48; Silveira 1998, pp. 57-58).

The species is highly adapted to shallow, rapid-flowing riverine conditions and, therefore, can not occupy the lacustrine conditions of reservoirs that result from dam building activities within their occupied range (Hughes
et al.
2006, pp. 23, 41). The loss of the species' terrestrial habitat has occurred due to the removal of forest cover and suitable nesting trees adjacent to occupied river corridors.

A variety of secondary impacts that degrade suitable habitats have also resulted from the above activities and represent significant risks to the Brazilian merganser. These secondary impacts include increased runoff and severe siltation from agricultural fields, livestock pastures, deforestation, diamond mining, and population centers; changes in hydrologic conditions and local water tables as a result of dam operations (
e.g.,
flood control, power generation) and excessive pumping for irrigation or domestic and industrial water use; and increases in water pollutants due to agricultural, industrial, and domestic waste products (Benstead 1994, p. 8; Bianchi
et al.
2005, p. 73; BLI 2007a, pp. 1-6; Braz
et al.
2003, p. 70; Collar
et al.
1994, p. 51; del Hoyo
et al.
1992, p. 625; Ducks Unlimited 2007, p. 1; Hughes
et al.
2006, pp. 40-48; Lamas and Santos 2004, p. 40; Pineschi 1999, p. 1). These secondary impacts negatively affect the Brazilian merganser by reducing water clarity, altering water depths and flow patterns, removing or limiting populations of preferred prey species; introducing toxic compounds; and creating barriers to movements and producing hazardous conditions along river corridors that limit interchange between the species' remaining subpopulations (see Factor E). These secondary impacts also increase the risk of introducing disease vectors and expanding populations of potential predator and competitor species into areas occupied by the Brazilian merganser (see Factor C).

Summary of Factor A

The above mentioned human activities and their secondary impacts have significantly reduced the amount of suitable habitat for the Brazilian merganser (Benstead 1994, p. 8;

Benstead
et al.
1994, p. 36; BLI 2007a, pp. 1-6; Collar and Andrew 1988, p. 21; Collar
et al.
1992, pp. 83-84; Collar
et al.
1994, p. 51; Hughes
et al.
2006, pp. 37-48; Silveira 1998, pp. 57-58), and the remaining areas of occupied habitat are highly fragmented (see Factor E). In addition, these activities are ongoing and continue to adversely impact all of the remaining suitable habitat within the Atlantic Forest and Cerrado biomes that may still harbor the Brazilian merganser (BLI 2003a, p. 4; BLI 2003b, pp. 1-2; BLI 2007a, pp. 1-7; Brannstrom 2000, p. 326; Ducks Unlimited 2007, p. 1; Harris and Pimm 2004, p. 1610; Hughes
et al.
2006, pp. 37-48; Morellato and Haddad 2000, p. 786; Saatchi
et al.
2001, pp. 868-873; Tabanez and Viana 2000, pp. 929-932). Even with the recent passage of national forest policy and in light of many other legal protections in Brazil (see Factor D), the rate of habitat loss throughout southeastern Brazil has increased since the mid-1990s (CEPF 2001, p. 10; Hodge
et al.
1997, p. 1; Rocha
et al.
2005, p. 270). Furthermore, because the Brazilian merganser's extant population is already extremely small, highly fragmented, and believed to be declining (BLI 2007a, pp. 1-4), any further loss or degradation of its remaining suitable habitat will severely impact the species (see Factor E). Therefore, we find that destruction and modification of habitat are threats to the continued existence of the Brazilian merganser throughout its range.

B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

Historically, there was likely little range-wide hunting pressure on the Brazilian merganser, presumably due to the species' secretive nature, naturally low densities in relatively inaccessible areas, and poor palatability (Partridge 1956, p. 478). However, low levels of subsistence hunting of some local populations still occurs, most notably in Argentina (Benstead 1994, p. 8; del Hoyo
et al.
1992, p. 625; Hughes
et al.
2006, p. 48).

Since the first formal description of the species in the early 1800s, the Brazilian merganser has also been collected for scientific study and museum exhibition (BLI 2007a, p. 2; Hughes
et al.
2006, p. 46). Past hunting and specimen collection may have contributed to the species' decline in some areas (Hughes
et al.
2006, p. 46). These activities continue today, although presumably at low levels (Benstead 1994, p. 8; Hughes
et al.
2006, p. 48; Lamas and Santos 2004, p. 39).

Summary of Factor B

Species collection for scientific study and museum exhibition, and hunting, are believed to affect the population of the Brazilian merganser. Considering the extremely small size and level of fragmentation of the extant Brazilian merganser population, the removal or dispersal of any individuals from a local area, or even a slight decline in the population's fitness, represent significant risks to the species' overall viability (see Factor E). However, we do not have information on the extent of species collection or hunting to determine whether these activities are a threat to the continued existence of the species. As a result, we are not considering overutilization to be a contributing factor to the continued existence of the Brazilian merganser.

C. Disease or Predation

Extensive human activity in previously undisturbed or isolated areas can lead to the introduction and spread of exotic diseases, some of which (
e.g.,
West Nile virus) can negatively impact endemic bird populations (Neotropical News 2003, p. 1; Naugle
et al.
2004, p. 704). In addition, there are a number of suspected predators of the Brazilian merganser (Hughes
et al.
2006, p. 44; Lamas and Santos 2004, p. 39; Partridge 1956, p. 486). Partridge (1956, p. 480) hypothesized that the species' distribution may be naturally limited to upper river tributaries above waterfalls due to predation of their young by large predatory fish, such as the dourado (
Salminus brasiliensis,
syn.
maxillosus
). Finally, extensive human activity in previously undisturbed or isolated areas can result in altered predator or competitor (
e.g.,
cormorant (
Phalacrocorax
sp.)) populations and the introduction of various exotic predator species, such as feral dogs (
Canis familiaris
) and game fish like largemouth bass (
Micropterus salmoides
) (Hughes
et al.
2006, pp. 44-45).

The available information indicates that there is a greatly expanded human population within the Brazilian merganser's historic range and that the species' extant population is extremely small, highly fragmented, and likely declining. Although large, stable populations of wildlife species have adapted to natural levels of disease and predation within their historic ranges, any additive mortality to the Brazilian merganser population or a decrease in its fitness due to an increase in the incidence of disease or predation could adversely impact the species' overall viability (see Factor E). However, while these potential influences remain a concern for future management of the species, we are not aware of any information currently available that specifically indicates the occurrence of disease in the Brazilian merganser, or that documents actual predation levels incurred by any of the species' local subpopulations. As a result, we are not considering disease or predation to be a contributing factor to the continued existence of the Brazilian merganser.

D. The Inadequacy of Existing Regulatory Mechanisms

The Brazilian merganser is legally protected by national legislation promulgated by the governments in all three countries where it historically occurred (Hughes
et al.
2006, pp. 50-57). In Brazil, where the vast majority of the species' extant population and remaining suitable habitats occur (BLI 2007a, pp. 1-2; Hughes
et al.
2006, pp. 28-31), the Brazilian merganser is formally recognized as “endangered” (Order No. 1.522), and there are regulatory mechanisms that require direct protection of the species (ECOLEX 2007, pp. 1-2). These include measures that prohibit, or regulate through Federal agency oversight, the following activities with regard to endangered species: export and international trade (
e.g.,
Decree No. 76.623, Order No. 419-P), hunting (
e.g.,
Act No. 5.197), collection and research (Order No. 332), captive propagation (Order No. 5), and general harm (
e.g.,
Decree No. 3.179).

There are also a wide range of regulatory mechanisms in Brazil that indirectly protect the Brazilian merganser through measures that protect its remaining suitable habitats (ECOLEX 2007, pp. 2-5). For example, there are measures that: (1) Prohibit exploitation of the remaining primary forests within the Atlantic Forest biome and gallery forests adjacent to river corridors (
e.g.,
Decree No. 750, Resolution No. 10, Act No. 7.754); (2) govern various practices associated with the management of primary and secondary forests, such as logging, charcoal production, reforestation, recreation, and water resources (
e.g.,
Resolution No. 9, Act No. 4.771, Decree No. 1.282, Decree No. 3.420, Order No. 74-N, Act No. 7.803); (3) establish provisions for controlling forest fires (
e.g.,
Decree No. 97.635, Order No. 231-P, Order No. 292-P, Decree No. 2.661); and (4) regulate industrial developments, such as hydroelectric plants and biodiesel production (
e.g.,
Normative Instruction No. 65, Law No. 11.116). Measures also exist (
e.g.,
Law No. 11.516, Act No. 7.735, Decree No.

78, Order No. 1, Act No. 6.938) that direct Federal and State agencies to promote the protection of lands and natural resources under their jurisdictions (ECOLEX 2007, pp. 5-6).

Regulatory mechanisms in Brazil govern the formal establishment and management of protected areas to promote conservation of the country's natural resources (ECOLEX 2007, pp. 6-7). These mechanisms generally aim to protect endangered wildlife and plant species, genetic resources, overall biodiversity, and native ecosystems on Federal, State, and privately owned lands (
e.g.,
Law No. 9.985, Law No. 11.132, Resolution No. 4, Decree No. 1.922). Brazil's formally established protection areas are categorized based on their overall management objectives (
e.g.,
National Parks versus Biological Reserves) and, based on those categories, allow varying uses and provide varying levels of protection for specific resources (Costa 2007, pp. 5-19). Four of Brazil's protected areas represent the major sites where the Brazilian merganser still occurs (Hughes
et al.
2006, pp. 53-54). These areas are considered critical for protecting some of the species' key remaining subpopulations (Bianchi
et al.
2005, pp. 72-74; BLI 2007a, pp. 1-2; Braz
et al.
2003, pp. 68-71; Bruno
et al.
2006, p. 30; Collar
et al.
1992, pp. 84-85; del Hoyo
et al.
1992, p. 625; Lamas and Santos 2004, pp. 39-40; Silveira 1998, pp. 57-58). Notable among these areas are the Serra da Canastra National Park in Minas Gerais, which currently encompasses a portion of the species' largest known subpopulation (Bruno
et al.
2006, p. 25), and the Chapada dos Veadeiros National Park in Goiás (Bianchi
et al.
2005, pp. 72-73). The Service recently provided funding for a project to develop and strengthen conservation partnerships with local agricultural producers in the Serra da Canastra region, which could benefit the Brazilian merganser (USFWS 2006, p. 3).

Although four categories of protected areas under Brazilian law include important sites where the species occurs, unregulated tourism, resource extraction, and livestock grazing continue in these areas and pose threats to the Brazilian merganser. In addition, not all of the remaining Brazilian mergansers occur in these protected areas. Some key areas where the species occurs are currently not formally protected and are subject to ongoing threats, such as proposed hydropower projects, logging, and continuing development.

Due to various reasons (
e.g.,
lack of funding, personnel, or local management commitment), some of Brazil's protected areas exist without current capacity to achieve their stated natural resource objectives (IUCN 1999, pp. 23-24; Neotropical News 1996, pp. 9-10; Neotropical News 1999, p. 9; Costa 2007, p. 7). For example, the Worldwide Fund for Nature found in its study that 47 of 86 protected areas were found to be below the minimum level of implementation of Federal requirements, with only 7 considered to be fully implemented (Neotropical News 1999, p. 9).

Despite the existence of these regulatory mechanisms, habitat loss throughout the Atlantic Forest biome has increased for more than a decade (BLI 2003a, p. 4; BLI 2003b, pp. 1-2; Braz
et al.
2003, p. 70; Collar
et al.
1992, p. 84; Hughes
et al.
2006, p. 61; Lamas and Santos 2004, p. 40; The Nature Conservancy 2007, p. 2; Neotropical News 1997b, p. 11; Scott and Brooke 1985, p. 118). Illegal or unauthorized activities that continue to impact the Brazilian merganser include logging of gallery forests within riverine buffer areas; encroachment of logging, livestock grazing, and subsistence activities within protected primary and secondary forests; hunting; intentional burning; and collection of eggs and adult birds from the wild (BLI 2003b, p. 1; Hughes
et al.
2006, p. 61; The Nature Conservancy 2007, p. 2).

In the past, the Brazilian government, through various regulations, policies, incentives, and subsidies, has actively encouraged settlement of previously undeveloped lands in southeastern Brazil, which helped facilitate the large-scale conversions that have occurred in the Atlantic Forest and Cerrado biomes (Brannstrom 2000, p. 326; Butler 2007, p. 3; Conservation International 2007c, p. 1; Pivello 2007, p. 2; Ratter
et al.
1997, pp. 227-228; Saatchi
et al.
2001, p. 874). Some of these projects, if developed, would impact important sites for the Brazilian merganser and would affect habitat within and adjacent to established protection areas. These projects include further development of dams for hydroelectric power, irrigation, or municipal water supplies; expansion of agricultural practices, primarily for soybean production; and increasing tourism enterprises (Braz
et al.
2003, p. 70; Hughes
et al.
2006, pp. 51-56).

Summary of Factor D

Brazil's wide variety of laws requiring resource protection would ultimately benefit the Brazilian merganser, but they are tested by the intense development pressure that exists within the species' range. Government-sponsored measures in Brazil continue to facilitate development projects, however regulatory mechanisms also exist that require protection of the Brazilian merganser and its habitat. Despite the existence of these regulatory mechanisms, there are a few challenges, including the fact that protected areas do not address all the threats to the Brazilian merganser, protected areas do not encompass all occupied habitat of the species, there are government sponsored programs that encourage development within the range of the species, and protections that would benefit the species are not adequately enforced. As a result, threats to the species' remaining habitat are ongoing (see Factor A). Therefore, when combined with Factors A and E, we find that the existing regulatory mechanisms are inadequate to ameliorate the current threats to the Brazilian merganser throughout its range.

E. Other Natural or Manmade Factors Affecting the Continued Existence of the Species

Under this factor we explore whether three risks, represented by demographic, genetic, and environmental stochastic events, are substantive to threaten the continued existence of the Brazilian merganser. In basic terms, demographic stochasticity is defined by chance changes in the population growth rate for the species (Gilpin and Soulé 1986, p. 27). Population growth rates are influenced by individual birth and death rates (Gilpin and Soulé 1986, p. 27), immigration and emigration rates, as well as changes in population sex ratios. Natural variation in survival and reproductive success of individuals and chance disequilibrium of sex ratios may act in concert to contribute to demographic stochasticity (Gilpin and Soulé 1986, p. 27). Genetic stochasticity is caused by changes in gene frequencies due to genetic drift, and diminished genetic diversity, and/or effects due to inbreeding (
i.e.,
inbreeding depression) (Lande 1995, p. 786). Inbreeding can have individual or population-level consequences either by increasing the phenotypic expression (the outward appearance or observable structure, function or behavior of a living organism) of recessive, deleterious alleles or by reducing the overall fitness of individuals in the population (Charlesworth and Charlesworth 1987, p. 231; Shaffer 1981, p. 131). Environmental stochasticity is defined as the susceptibility of small, isolated populations of wildlife species to natural levels of environmental variability and related “catastrophic” events (
e.g.,
severe storms, prolonged drought, extreme cold spells, wildfire)

(Young 1994, pp. 410-412; Mangel and Tier 1994, p. 612; Dunham
et al.
1999, p. 9). Each risk will be analyzed specifically for the Brazilian merganser.

Small, isolated populations of wildlife species are susceptible to demographic and genetic problems (Shaffer 1981, pp. 130-134). These threat factors, which may act in concert, include: natural variation in survival and reproductive success of individuals, chance disequilibrium of sex ratios, changes in gene frequencies due to genetic drift, diminished genetic diversity and associated effects due to inbreeding (
i.e.,
inbreeding depression), dispersal of just a few individuals, a few clutch failures, a skewed sex ratio in recruited offspring over just one or a few years, and chance mortality of just a few reproductive-age individuals.

The Brazilian merganser has likely always been a rare species, with small local populations occupying the naturally restricted sites of suitable habitat within the upper-tributaries of river systems in east-central South America (Lamas and Santos 2004, pp. 38-39; Partridge 1956, pp. 477-478). In addition, while there is no direct evidence currently available, Yamashita (in Hughes
et al.
2006, p. 43) speculated that the species has likely always had a naturally low level of genetic variability as a result of its life history strategy.

It was further speculated that inbreeding in the Brazilian merganser has not significantly affected the species, presumably due to the species' natural tolerance for low genetic variability (Hughes
et al.
2006, p. 43). However, relatively low levels of genetic interchange between local subpopulations can act to maintain the genetic viability of a metapopulation (Vilà
et al.
2002, p. 91; Wang 2004, p. 332) and, historically, it seems likely that the Brazilian merganser maintained such minimum levels of interchange across its occupied range in order for its subpopulations to have persisted (Middleton and Nisbet 1997, p. 107).

In the absence of more species-specific life history data, a general approximation of a minimum viable population size is referred to as the 50/500 rule (Franklin 1980, p. 147). This rule states that an effective population (N
e
) of 50 individuals is the minimum size required to avoid imminent risks from inbreeding. N
e
represents the number of animals in a population that actually contribute to reproduction, and is often much smaller than the total number of individuals in the population (N). For example, not all individuals reproduce. Furthermore, the rule states that the long-term fitness of a population requires an N
e
of at least 500 individuals so that it will not lose its genetic diversity over time and will maintain an enhanced capacity to adapt to changing conditions.

The available information indicates that the extant Brazilian merganser population is extremely small (
i.e.,
between 50 and 249 individuals) and highly fragmented. The lower limit of the population (50 individuals) teeters on the edge of the minimum number of individuals required to avoid imminent risks from inbreeding (N
e
= 50). The current maximum estimate of 249 individuals for the entire population (BLI 2007a, p. 1) is only half of the upper threshold (N
e
= 500) required to maintain genetic diversity over time and to maintain an enhanced capacity to adapt to changing conditions. Furthermore, these small, fragmented populations are likely reproductively isolated due to extensive habitat modifications that have taken place throughout the species' historic distribution (see Factor A). As such, we currently consider the Brazilian merganser to be at risk due to its lack of near- and long-term genetic viability.

Available information indicates that the Brazilian merganser is still subject to low levels of hunting, specimen collection, and other human disturbances (see Factors E and D). For species with large and/or well-interconnected subpopulations, low levels of the above influences would normally be of little consequence. However, considering the extremely small size and likely isolation of the species' extant subpopulations, and the likelihood of continued fragmentation of its occupied habitats, the removal or dispersal of any individuals from a local area, or even a slight decline in the individual or population fitness of these birds, represent significant risks to the continued existence of the Brazilian merganser.

Various past and ongoing human activities and their secondary influences continue to impact all of the remaining suitable habitats that may still harbor the Brazilian merganser (see Factors A and D). We expect that any additional loss or degradation of habitats that are used by the Brazilian merganser will have disproportionately greater impacts on the species due to the population's fragmented state. This is because with each contraction of an existing subpopulation, the likelihood of interchange with other subpopulations within patches decreases, while the likelihood of its complete reproductive isolation increases.

The combined effects of habitat fragmentation (Factor A) and genetic and demographic stochasticity on a species population are referred to as patch dynamics. Patch dynamics can have profound effects on fragmented subpopulations and can potentially reduce a species' respective effective population by orders of magnitude (Gilpin and Soulé 1986, p. 31). For example, an increase in habitat fragmentation can separate subpopulations to the point where individuals can no longer disperse and breed among habitat patches, causing a shift in the demographic characteristics of a population and a reduction in genetic fitness (Gilpin and Soulé 1986, p. 31). Without efforts to maintain buffer areas and reconnect some of the remaining tracts of suitable habitat near the species' currently occupied sites, it is doubtful that the individual tracts are currently large enough to support viable populations, and the eventual loss of any small, isolated populations appears to be inevitable (Goerck 1997, p. 117; Harris and Pimm 2004, pp. 1609-1610; IUCN 1999, pp. 23-24; Machado and Da Fonseca 2000, pp. 914, 921-922; Saatchi
et al.
2001, p. 873; Scott and Brooke 1985, p. 118). Furthermore, as a species' status continues to decline, often as a result of deterministic forces such as habitat loss or overutilization, it will become increasingly vulnerable to a broad array of other forces. If this trend continues, its ultimate extinction due to one or more stochastic events becomes more likely.

We expect that the Brazilian merganser's increased vulnerability to demographic stochasticity and inbreeding will be operative even in the absence of any human-induced threats or stochastic environmental events, which only act to further exacerbate the species' vulnerability to local extirpations and eventual extinction. Demographic and genetic stochastic forces typically operate synergistically. Initial effects of one threat factor can later exacerbate the effects of other threat factors, as well as itself (Gilpin and Soulé 1986, pp. 25-26). For example, any further fragmentation of populations will, by definition, result in the further removal or dispersal of individuals, which will exacerbate the other threats. Conversely, lack of a sufficient number of individuals in a local area or a decline in their individual or collective fitness may cause a decline in the population size, despite the presence of suitable habitat patches.

Small, isolated populations of wildlife species, such as the Brazilian merganser, are also susceptible to natural levels of environmental variability and related “catastrophic” events (
e.g.,
severe storms, prolonged

drought, extreme cold spells, wildfire), which we will refer to as environmental stochasticity (Dunham
et al.
1999, p. 9; Mangel and Tier 1994, p. 612; Young 1994, pp. 410-412). A single stochastic environmental event can severely reduce existing wildlife populations and, if the affected population is already small or severely fragmented, it is likely that demographic stochasticity or inbreeding will become operative, which would place the population in jeopardy (Gilpin and Soulé 1986, p. 27; Lande 1995, pp. 787-789).

In addition to these stochastic threats, the Brazilian merganser is sensitive to human disturbance activities. Each breeding pair of the Brazilian merganser requires relatively long segments of river (up to
ca.
12 km (7.5 mi)) (Braz
et al.
2003, p. 70; Bruno
et al.
2006, p. 30; Silvera 1998, pp. 57-58). Breeding success and recruitment of young in a local area is believed to be negatively affected by human disturbance. Sources of human disturbance include various ongoing activities associated with a vastly expanded human population within the species' occupied range, including tourism (
e.g.,
birding, river rafting, trekking, off-road vehicle use) and scientific research programs (Braz
et al.
2003, p. 70; Bruno
et al.
2006, p. 30; Silvera 1998, pp. 57-58).

Summary of Factor E

The small and declining numbers that make up the Brazilian merganser's population makes it susceptible to natural environmental variability or chance events. In addition to its declining numbers, the high level of population fragmentation makes the species susceptible to genetic and demographic stochasticity. Therefore, we find that demographic, genetic, and environmental stochastic events are a threat to the continued existence of the Brazilian merganser throughout its range.

Status Determination for the Brazilian merganser

We have carefully assessed the best available scientific and commercial information regarding the past, present, and potential future threats faced by the Brazilian merganser. Activities associated with a vastly expanded human population within the species' occupied range, including tourism (
e.g.,
birding, river rafting, trekking, off-road vehicle use), scientific research programs, livestock grazing, and infrastructure development, all represent multiple sources of additional disturbance to the Brazilian merganser. The species is currently at risk throughout all of its range due to ongoing threats of habitat destruction and modification (Factor A), and its lack of near- and long-term genetic viability due to threats associated with demographic, genetic, and environmental stochasticity (Factor E). Furthermore, we have determined that the existing regulatory mechanisms (Factor D) are not adequate to ameliorate the current threats to the species.

Section 3 of the Act defines an “endangered species” as “any species which is in danger of extinction throughout all or a significant portion of its range” and a “threatened species” as “any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” Based on the threats to the Brazilian merganser throughout its entire range, as described above, we determine that the Brazilian merganser is in danger of extinction throughout all of its range. Therefore, on the basis of the best available scientific and commercial information, we are proposing to list the Brazilian merganser as an endangered species throughout all of its range.

III. Cherry-throated Tanager (Nemosia rourei)

Species Description

The cherry-throated tanager has distinctive black plumage on its head with a white crown, black coloring on the back and wings, white feathers on its undersides, and red coloring on its throat and upper chest (BLI 2007g, p. 1).

Taxonomy

The cherry-throated tanager is a member of the Thraupidae family. It was first described by Cabanis in 1870 (BLI 2007g, p. 1).

Habitat and Life History

The cherry-throated tanager is endemic to the Atlantic Forest biome and inhabits the upper canopies of trees within humid, montane, primary forests (Bauer
et al.
2000, pp. 97-104; BLI 2007g, pp. 1-2; Venturini
et al.
2005, pp. 60-64). The cherry-throated tanager is a primary forest-obligate species that typically forages within the interior crowns of tall, epiphyte-laden trees and occasionally within lower levels (ca. 2 m (6.6 ft)) at the forest edge. The species' diet includes caterpillars, butterflies, ants, and various other arthropods (Bauer
et al.
2000, BLI 2007g, p. 1; p. 104; Venturini
et al.
2005, p. 65). Cherry-throated tanagers can be found in mixed-species flocks and appear to require relatively large territories (ca. 3.99 km
2
(1.544 mi
2
)) (Venturini
et al.
2005, p. 66). Within its current distribution, the species makes sporadic use of coffee (
Coffea
spp.), pine (
Pinus
spp.), and eucalyptus (
Eucalyptus
spp.) plantations, presumably as travel corridors between remaining patches of primary forest (Venturini
et al.
2005, p. 66).

Little is known about the breeding behavior of the cherry-throated tanager. However, a single field observation indicates that perhaps both sexes help build nests (Venturini
et al.
2002, pp. 43-44). An observed nest was constructed of moss, and possibly thin twigs, and the material was placed in natural depressions of branches near the trunk within the mid-canopy (Venturini
et al.
2002, pp. 43-44).

Range and Distribution

The cherry-throated tanager is found in primary forest habitats in Espírito Santo and, possibly, Minas Gerais and Rio de Janeiro, Brazil (BLI 2007g, p. 1). Since 1998, the cherry-throated tanager has been documented at two sites of remnant primary forest in south-central Espírito Santo. One site is located in Fazenda Pindobas IV in the municipality of Conceição; the other is found in Caetés, in the Vargem Alta municipality in southern Espírito Santo (30 km (18.6 mi) southeast of Pindobas) (Venturini
et al.
2005, p. 61).

Population Estimates

The cherry-throated tanager was presumed to be extinct because the species was only known from a single specimen collected in the 1800s and a reliable sighting of eight individuals from 1941 (Collar
et al.
1992, p. 896; Ridgely and Tudor 1989, p. 34; Scott and Brooke 1985, p. 126). However, the species was rediscovered in 1998 (Bauer
et al.
2000, p. 97; Venturini
et al.
2005, p. 60). IUCN estimates the population to range from 50 to 249 individuals, and it is believed to be declining (BLI 2007g, p. 1). However, Venturini
et al.
(2005, p. 66) speculate that the IUCN population estimate is too high, considering that the maximum number of individuals recently recorded was 14, including 6 birds in Pindobas and 8 birds in Caetés.

Conservation Status

IUCN considers the cherry-throated tanager to be “Critically Endangered” because its extant population is extremely small (estimated to be between 50 and 249 individuals), highly fragmented, and presumed to be declining (BLI 2007g, p. 1).

Summary of Factors Affecting the Cherry-Throated Tanager

A. The Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range

Based on a number of recent estimates, 92 to 95 percent of the area historically covered by tropical forests within the Atlantic Forest biome has been converted or severely degraded as a result of human activities (Butler 2007, p. 2; Conservation International 2007a, p. 1; Höfling 2007, p. 1; Morellato and Haddad 2000, p. 786; Myers
et al.
2000, pp. 853-854; The Nature Conservancy 2007, p. 1; Saatchi
et al.
2001, p. 868; World Wildlife Fund 2007, pp. 2-41). In addition to the overall loss and degradation of native habitat within this biome, the remaining tracts of habitat are severely fragmented. The current rate of habitat decline within the Atlantic Forest is unknown.

The region has the two largest cites in Brazil, São Paulo and Rio de Janeiro, and is home to approximately 70 percent of Brazil's 169 million people (CEPF 2002; IBGE 2007). The major human activities that have resulted in the loss, degradation, and fragmentation of native habitats within the Atlantic Forest biome include extensive establishment of agricultural fields (
e.g.,
soy beans, sugarcane, and corn), plantations (
e.g.,
eucalyptus, pine, coffee, cocoa, rubber, and bananas), livestock pastures, centers of human habitation, and industrial developments (
e.g.,
charcoal production, steel plants, and hydropower reservoirs). Forestry practices (
e.g.,
commercial logging), subsistence activities (
e.g.,
fuelwood collection), and changes in fire frequencies also contribute to the degradation of native habitat (BLI 2003a, p. 4; Júnior
et al.
1995, p. 147; The Nature Conservancy 2007, p. 2; Nunes and Kraas 2000, p. 44; Peixoto and Silva 2007, p. 5; Saatchi
et al.
2001, pp. 868-869; Scott and Brooke 1985, p. 118; World Wildlife Fund 2007, pp. 3-51).

Most of the tropical forest habitats believed to have been used historically by the cherry-throated tanager have been converted or are severely degraded due to the above human activities (Bauer
et al.
2000, pp. 98-105; BLI 2007, p. 2; Ridgely and Tudor 1989, p. 34; Venturini
et al.
2005, p. 68). Degraded and fragmented forests experience a decrease in gene flow, which may cause inbreeding and decreased fitness of forest species (Tabanez and Viana 2000, pp. 929-932). In addition, increased liana density has been observed in degraded and fragmented Atlantic forests of Brazil. Liana infestation of these forest fragments cause tree falls and encourage gap-opportunistic species to take over (Tabanez and Viana 2000, pp. 929-932), thus altering the old forest structure and the cherry-throated tanager's habitat.

Secondary impacts that are associated with forest fragmentation and degradation include the potential introduction of disease vectors or exotic predators within the species' historic range (see Factor C). As a result of these secondary impacts, there is often a time lag between the initial conversion or degradation of suitable habitats and the extinction of endemic bird populations (Brooks
et al.
1999a, p. 1; Brooks
et al.
1999b, p. 1140). Therefore, even without further habitat loss or degradation, the cherry-throated tanager remains at risk from past impacts to its primary forest habitats.

Summary of Factor A

The above human activities and their secondary impacts continue to threaten the last known tracts of habitat within the Atlantic Forest biome that may still harbor the cherry-throated tanager (BLI 2003a, p. 4; BLI 2007g, p. 5; Conservation International 2007a, p. 1; Höfling 2007, p. 1; The Nature Conservancy 2007, p. 1; Venturini
et al.
2005, p. 68; World Wildlife Fund 2007, pp. 3-51). Because the species' extant population is extremely small, highly fragmented, and believed to be declining (BLI 2007g, p. 1), any further loss or degradation of its remaining suitable habitat will adversely impact the cherry-throated tanager. Therefore, we find that past and ongoing destruction and modification of the cherry-throated tanager's habitat are threats to the continued existence of the species throughout its range.

B. Overutilization for Commercial, Recreational, Scientific, or Educational Purposes

The extant population of the cherry-throated tanager is considered to be extremely small, highly fragmented, and declining (BLI 2007g, p. 1; Venturini
et al.
2005, p. 66). Because of the cherry-throated tanager's rarity, it has been recommended that no further specimen collection of the species occur (Collar
et al.
1992, p. 896). However we do not have specific information as to the level of specimen collection, scientific research, or birding that occurs. Although the removal or dispersal of any individuals or even a slight decline in the species' fitness due to any intentional or inadvertent disturbances would represent significant risks to the cherry-throated tanager's overall viability (see Factor E), we are not aware of any information currently available that indicates overutilization of the cherry-throated tanager for commercial, recreational, scientific, or educational purposes is occurring. As a result, we are not considering overutilization to be a contributing factor to the continued existence of the cherry-throated tanager.

C. Disease or Predation

Large, stable populations of wildlife species have adapted to natural levels of disease and predation within their historic ranges. However, the extant population of the cherry-throated tanager is considered to be extremely small, highly fragmented, and declining, making it particularly vulnerable to slight levels of disease and predation.

Extensive human activity in previously undisturbed or isolated areas can lead to the introduction and spread of exotic diseases, some of which (
e.g.,
West Nile virus) can negatively impact endemic bird populations (Naugle
et al.
2004, p. 704; Neotropical News 2003, p. 1). It can also result in altered predator populations and the introduction of exotic predator species, some of which (
e.g.,
feral cats (
Felis catus
) and rats (
Ratus
sp.)) can be especially harmful to populations of endemic bird species (American Bird Conservancy 2007, p. 1; Courchamp
et al.
1999, p. 219; Duncan and Blackburn 2007, pp. 149-150; Salo
et al.
2007, pp. 1241-1242; Small 2005, p. 257). Any additive mortality to the cherry-throated tanager population or a decrease in its fitness due to an increase in the incidence of disease or predation would represent significant risks to the species' overall viability (see Factor E). However, while these potential influences remain a concern for future management of the species, we are not aware of any information currently available that indicates the occurrence of disease in the cherry-throated tanager, or that documents any predation incurred by the species. As a result, we are not considering disease or predation to be a contributing factor to the continued existence of the cherry-throated tanager.

D. The Inadequacy of Existing Regulatory Mechanisms

The cherry-throated tanager is formally recognized as “endangered” in Brazil (Order No. 1.522) and is directly protected by various laws promulgated by the Brazilian government (BLI 2007, p. 2; Collar
et al.
1992, p. 896; ECOLEX 2007, pp. 1-2). For example, there are measures that prohibit, or regulate through Federal agency oversight, the following activities with regard to endangered species: export and international trade (
e.g.,
Decree No.

76.623, Order No. 419-P), hunting (
e.g.,
Act No. 5.197), collection and research (Order No. 332), captive propagation (Order No. 5), and general harm (
e.g.,
Decree No. 3.179).

In addition, there are a wide range of regulatory mechanisms in Brazil that indirectly protect the cherry-throated tanager through measures that protect its remaining suitable habitat (ECOLEX 2007, pp. 2-5). For example, there are measures that: (1) Prohibit exploitation of the remaining primary forests within the Atlantic Forest biome (
e.g.,
Decree No. 750, Resolution No. 10); (2) govern various practices associated with the management of primary and secondary forests, such as logging, charcoal production, reforestation, recreation, and water resources (
e.g.,
Resolution No. 9, Act No. 4.771, Decree No. 1.282, Decree No. 3.420, Order No. 74-N, Act No. 7.803); (3) establish provisions for controlling forest fires (
e.g.,
Decree No. 97.635, Order No. 231-P, Order No. 292-P, Decree No. 2.661); and (4) regulate industrial developments, such as hydroelectric plants and biodiesel production (
e.g.,
Normative Instruction No. 65, Law No. 11.116). Finally, there are various measures (
e.g.,
Law No. 11.516, Act No. 7.735, Decree No. 78, Order No. 1, Act No. 6.938) that direct Federal and state agencies to promote the protection of lands and natural resources under their jurisdictions (ECOLEX 2007, pp. 5-6).

There are also various regulatory mechanisms in Brazil that govern the formal establishment and management of protected areas to promote conservation of the country's natural resources (ECOLEX 2007, pp. 6-7). These mechanisms generally aim to protect endangered wildlife and plant species, genetic resources, overall biodiversity, and native ecosystems on Federal, state, and privately owned lands (
e.g.
, Law No. 9.985, Law No. 11.132, Resolution No. 4, Decree No. 1.922). Brazil's formally established protection areas are categorized based on their overall management objectives (
e.g.
, National Parks versus Biological Reserves) and, based on those categories, allow varying uses and provide varying levels of protection for specific resources (Costa 2007, pp. 5-19).

Few sites have recent confirmed observations of the cherry-throated tanager. There have been possible sightings of the cherry-throated tanager in the Augusto Ruschi Biological Reserve (also known as Nova Lombardia Biological Reserve), which comprises approximately 5,000 hectares (ha) (12,355 acres (ac)) in Espiritu Santo; however, there is doubt that the species occupies the reserve due to a lack of records by ornithologists, since the 1970s, of birds that frequent the area (BLI 2007, p. 2; Bauer
et al.
2000, p. 106; Scott 1997, p. 62). One of the key sites still occupied by the species is the Pindobas IV Farm. It has been recommended that the farm be formally designated as a protected area to help ensure the species' future protection, and the owners of this farm have expressed interest in this recommendation (Bauer
et al.
2000, p. 106; BLI 2007g, p. 2). Under Brazilian law, the remaining native forest on the owner's land could be designated as a Private Natural Heritage Reserve.

For various reasons (
e.g.
, lack of funding, personnel, or local management commitment), some of Brazil's protected areas exist without the current capacity to achieve their stated natural resource objectives (ADEJA 2007, pp. 1-2; Bruner
et al.
2001, p. 125; Costa 2007, p. 7; IUCN 1999, pp. 23-24; Neotropical News 1996, pp. 9-10; Neotropical News 1999, p. 9). Enforcement has been a challenge to implement. Therefore, even with the further designation of protected areas, it is unlikely that all of the identified resource concerns for the cherry-throated tanager (
e.g.
, residential and agricultural encroachment, resource extraction, unregulated tourism, and grazing) would be sufficiently addressed at these sites.

In the past, the Brazilian government, through various regulations, policies, incentives, and subsidies, has actively encouraged settlement of previously undeveloped lands in southeastern Brazil (Brannstrom 2000, p. 326; Butler 2007, p. 3; Conservation International 2007c, p. 1; Pivello 2007, p. 2; Ratter
et al.
1997, pp. 227-228; Saatchi
et al.
2001, p. 874). More recently, the Brazilian government has given greater recognition to the environmental consequences of such rapid expansion, and has taken steps to better manage some of the natural resources potentially impacted (Butler 2007, p. 7; Costa 2007, p. 7; Neotropical News 1997a, p. 10; Neotropical News 1997b, p. 11; Neotropical News 1998b, p. 9; Neotropical News 2003, p. 13; Nunes and Kraas 2000, p. 45; Venturini
et al.
2005, p. 68). Despite these efforts, pressures to develop areas containing cherry-throated tanager habitat continue (ADEJA 2007, pp. 1-2; BLI 2007d, p. 2; Tobias and Williams 1996, p. 65).

Summary of Factor D

Brazil is faced with competing priorities of encouraging development for economic growth and resource protection. Although there are various government-sponsored measures that remain in place in Brazil that continue to facilitate development projects, there are also a wide variety of regulatory mechanisms in Brazil that require protection of the cherry-throated tanager and its habitat throughout the species' potentially occupied range. Due to competing priorities, threats to the species' remaining habitat are ongoing (see Factor A). Therefore, when combined with Factors A and E, we find that the existing regulatory mechanisms are inadequate to ameliorate the current threats to the cherry-throated tanager throughout its range.

E. Other Natural or Manmade Factors Affecting the Continued Existence of the Species

Under this factor we explore whether three risks, represented by demographic, genetic, and environmental stochastic events, are substantive to threaten the continued existence of the cherry-throated tanager. In basic terms, demographic stochasticity is defined by chance changes in the population growth rate for the species (Gilpin and Soulé 1986, p. 27). Population growth rates are influenced by individual birth and death rates (Gilpin and Soulé 1986, p. 27), immigration and emigration rates, as well as changes in population sex ratios. Natural variation in survival and reproductive success of individuals and chance disequilibrium of sex ratios may act in concert to contribute to demographic stochasticity (Gilpin and Soulé 1986, p. 27). Genetic stochasticity is caused by changes in gene frequencies due to genetic drift, and diminished genetic diversity, and/or effects due to inbreeding (
i.e.
, inbreeding depression) (Lande 1995, p. 786). Inbreeding can have individual or population-level consequences either by increasing the phenotypic expression (the outward appearance or observable structure, function or behavior of a living organism) of recessive, deleterious alleles or by reducing the overall fitness of individuals in the population (Charlesworth and Charlesworth 1987, p. 231; Shaffer 1981, p. 131). Environmental stochasticity is defined as the susceptibility of small, isolated populations of wildlife species to natural levels of environmental variability and related “catastrophic” events (
e.g.
, severe storms, prolonged drought, extreme cold spells, wildfire) (Dunham
et al.
1999, p. 9; Mangel and Tier 1994, p. 612; Young 1994, pp. 410-412). Each risk will be analyzed specifically for the cherry-throated tanager.

Small, isolated populations of wildlife species are susceptible to demographic

and genetic problems (Shaffer 1981, pp. 130-134). These threat factors, which may act in concert, include: Natural variation in survival and reproductive success of individuals, chance disequilibrium of sex ratios, changes in gene frequencies due to genetic drift, diminished genetic diversity and associated effects due to inbreeding (
i.e.
, inbreeding depression), dispersal of just a few individuals, a few clutch failures, a skewed sex ratio in recruited offspring over just one or a few years, and chance mortality of just a few reproductive-age individuals.

The cherry-throated tanager is believed to have been rare historically with a naturally patchy, low density distribution, as indicated by the paucity of confirmed sightings of this colorful bird in areas that have been heavily visited by experienced birders (Bauer
et al.
2000, p. 98; Collar
et al.
1994, p. 190; Venturini
et al.
2005, pp. 63-64; BLI 2007g, p. 1). However, the species must have maintained a minimum level of genetic interchange among its local subpopulations in order for them to have persisted (Middleton and Nisbet 1997, p. 107; Vilà
et al.
2002, p. 91; Wang 2004, p. 332).

In the absence of more species-specific life history data, a general approximation of a minimum viable population size is referred to as the 50/500 rule (Franklin 1980, p. 147), as described under Factor E of the Brazilian merganser. Currently, the cherry-throated tanager is only known from two occupied sites where an approximate total of 14 birds have been observed since 1998 (Venturini
et al.
2005, p. 66). Given this information, current population estimates are 50 to 249 individuals, or below (BLI 2007g, p. 1; Venturini
et al.
2005, p. 66). The lower limit of the population is at or below the minimum number of individuals required to avoid imminent risks from inbreeding (N
e
= 50). The current maximum estimate of 249 individuals for the entire population is only half of the upper threshold (N
e
= 500) required to maintain genetic diversity over time and to maintain an enhanced capacity to adapt to changing conditions. As such, we currently consider the species to be at risk due to its lack of near- and long-term genetic viability.

Various past and ongoing human activities and their secondary influences continue to impact all of the remaining suitable habitats that may still harbor the cherry-throated tanager (see Factors A and D). We expect that any additional loss or degradation of habitats that are used by the cherry-throated tanager will have disproportionately greater impacts on the species due to the population's fragmented state. This is because with each contraction of an existing subpopulation, the likelihood of interchange with other subpopulations within patches decreases, while the likelihood of its complete reproductive isolation increases.

The combined effects of habitat fragmentation (Factor A) and genetic and demographic stochasticity on a species population are referred to as patch dynamics. Patch dynamics can have profound effects on fragmented subpopulations and can potentially reduce a species' respective effective population by orders of magnitude (Gilpin and Soulé 1986, p. 31). For example, an increase in habitat fragmentation can separate subpopulations to the point where individuals can no longer disperse and breed among habitat patches, causing a shift in the demographic characteristics of a population and a reduction in genetic fitness (Gilpin and Soulé 1986, p. 31). Without efforts to maintain buffer areas and reconnect some of the remaining tracts of suitable habitat near the species' currently occupied sites, it is doubtful that the individual tracts are currently large enough to support viable populations of many birds endemic to the Atlantic Forest, and the eventual loss of any small, isolated populations appears to be inevitable (Goerck 1997, p. 117; Harris and Pimm 2004, pp. 1609-1610; IUCN 1999, pp. 23-24; Machado and Da Fonseca 2000, pp. 914, 921-922; Saatchi
et al.
2001, p. 873; Scott and Brooke 1985, p. 118). Furthermore, as a species' status continues to decline, often as a result of deterministic forces such as habitat loss or overutilization, it will become increasingly vulnerable to a broad array of other forces. If this trend continues, its ultimate extinction due to one or more stochastic events becomes more likely.

We expect that the cherry-throated tanager's increased vulnerability to demographic stochasticity and inbreeding will be operative even in the absence of any human-induced threats or stochastic environmental events, which only act to further exacerbate the species' vulnerability to local extirpations and eventual extinction. Demographic and genetic stochastic forces typically operate synergistically. Initial effects of one threat factor can later exacerbate the effects of other threat factors, as well as itself (Gilpin and Soulé 1986, pp. 25-26). For example, any further fragmentation of populations will, by definition, result in the further removal or dispersal of individuals, which will exacerbate the other threats. Conversely, lack of a sufficient number of individuals in a local area or a decline in their individual or collective fitness may cause a decline in the population size, despite the presence of suitable habitat patches.

Small, isolated populations of wildlife species, such as the cherry-throated tanager, are also susceptible to natural levels of environmental variability and related “catastrophic” events (
e.g.
, severe storms, prolonged drought, extreme cold spells, wildfire), which we will refer to as environmental stochasticity (Dunham
et al.
1999, p. 9; Mangel and Tier 1994, p. 612; Young 1994, pp. 410-412). A single stochastic environmental event can severely reduce existing wildlife populations and, if the affected population is already small or severely fragmented, it is likely that demographic stochasticity or inbreeding will become operative, which would place the population in jeopardy (Gilpin and Soulé 1986, p. 27; Lande 1995, pp. 787-789).

Summary of Factor E

The small and declining numbers that make up the cherry-throated tanager's population makes it susceptible to natural environmental variability or chance events. In addition to its declining numbers, the high level of population fragmentation makes the species susceptible to genetic and demographic stochasticity. Therefore, we find that demographic, genetic, and environmental stochastic events are a threat to the continued existence of the cherry-throated tanager throughout its range.

Status Determination for the Cherry-throated Tanager

We have carefully assessed the best available scientific and commercial information regarding the past, present, and potential future threats faced by the cherry-throated tanager. The species is currently at risk throughout all of its range due to ongoing threats of habitat destruction and modification (Factor A), and its lack of near- and long-term genetic viability due to threats associated with demographic, genetic, and environmental stochasticity (Factor E). Furthermore, we have determined that the existing regulatory mechanisms (Factor D) are not adequate to ameliorate the current threats to the cherry-throated tanager.

Section 3 of the Act defines an “endangered species” as “any species which is in danger of extinction throughout all or a significant portion of its range” and a “threatened species” as “any species which is likely to become

an endangered species within the foreseeable future throughout all or a significant portion of its range.” Based on the threats to the cherry-throated tanager throughout its entire range, as described above, we determine that the cherry-throated tanager is in danger of extinction throughout all of its range. Therefore, on the basis of the best available scientific and commercial information, we are proposing to list the cherry-throated tanager as an endangered species throughout all of its range.

IV. Fringe-backed Fire-eye (Pyriglena atra)

Species Description

The fringe-backed fire-eye has distinctive red eyes and measures approximately 17.5 cm (7 in). Males are black with a small patch on their backs of black feathers lined with white edges. Females are more of a reddish-brown color, with a black tail, brown underparts and a whitish throat (BLI 2007e, p. 1).

Taxonomy

The fringe-backed fire-eye belongs in the “antbird” family Thamnophilidae, and was first described by Swainson in 1825 (BLI 2007e, p. 1). Sick (1991, p. 416) describes this species to be similar to the white-backed fire-eye (
Pyriglena leuconota
). The fringe-backed fire-eye was previously referred to as Swainson's fire-eye, and is also called “Alapi noir” in French, “Fleckenmantel-Feuerauge” in German, and “Ojodefuego de Bahía” in Spanish (del Hoyo 2003, p. 637).

Habitat and Life History

The fringe-backed fire-eye is endemic to the Atlantic Forest biome and typically inhabits dense understories at the edges of lowland primary tropical forests (BLI 2007e, p. 2; Collar
et al.
1992, p. 677; del Hoyo
et al.
2003, p. 637). The species has also been found to occupy degraded forests and dense understories of secondary-growth forest stands. It can also occupy early-successional forest stands, but avoids any areas with open understories (
e.g.
, sunny openings, interior forest) (del Hoyo
et al.
2003, p. 637).

The fringe-backed fire-eye forages in dense, tangled vegetation with numerous horizontal perches within approximately 3 m (10 ft) of the ground, although it occasionally feeds higher up (ca. 10 m (33 ft)) (Collar
et al.
1992, p. 677; del Hoyo
et al.
2003, p. 637). The species typically occurs as individual birds, in closely associated pairs, or in small family groups. The bird often relies on army ant (
Eciton
sp.) swarms to flush their prey, which may include cockroaches (superfamily Blattoidea), grasshoppers (family Acrididae), winged ants (class Chilopoda), caterpillars (order Lepidoptera), and geckos (family Gekkonidae) (del Hoyo
et al.
2003, pp. 637-638; Sick 1993, pp. 403-404).

Limited specific information is known about the species' breeding behavior (del Hoyo
et al.
2003, p. 638). However, females of this genus typically lay two eggs in spherical nests that are approximately 10 cm (4 in) in diameter, have a side entrance, and are attached to vegetation within roughly 1 m (3.3 ft) of ground (Sick 1993, pp. 405-406). In addition, both sexes in this genus typically help to build nests, brood clutches, and attend their young (Sick 1993, pp. 405-406).

Range and Distribution

The fringe-backed fire-eye occurs along a narrow belt of coastal forest habitats from southern Sergipe to northeastern Bahia, Brazil (BLI 2007e, p. 1; Collar
et al.
1992, p. 677; del Hoyo
et al.
2003, p. 637; Sick 1993, p. 416). The species' entire population was previously believed to be restricted to a few sites of remnant primary forest, totaling roughly 9 km
2
(3.5 mi
2
) in northeastern Bahia. In 2002, approximately 18 individuals were observed in a forested site in Sergipe (del Hoyo
et al.
2003, p. 638). This discovery extended the species' known range to the north by approximately 175 km (109 mi) (del Hoyo
et al.
2003, p. 638). However, the fringe-backed fire-eye has not been located at several sites from where it was previously known in Bahia (del Hoyo
et al.
2003, p. 638).

Population Estimates

The fringe-backed fire-eye's extant population is estimated to be between 1,000 and 2,499 individuals. The available information indicates that the species' population is fragmented among 6 to 10 occupied areas, with the largest subpopulation between 50 and 249 individuals (BLI 2007e, p. 3). Its population, along with the extent and quality of its habitat, continues to decline (BLI 2007e, p. 1).

Conservation Status

IUCN considers the fringe-backed fire-eye to be “Endangered” because it has “a very small fragmented range, within which the extent and quality of its habitat are continuing to decline and where it is only known from a few localities” (BLI 2007e, p. 1). In addition, the species is protected under Brazilian law (Collar
et al
. 1992, p. 678).

Summary of Factors Affecting the Fringe-backed Fire-eye

A. The Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range

The fringe-backed fire-eye occurs in one of the most densely populated regions of Brazil, and most of the tropical forest habitats believed to have been used historically by the species have been converted or are severely degraded due to the wide range of human activities (BLI 2003a, p. 4; BLI 2007e, p. 2; Collar and Andrew 1988, p. 102; Collar
et al
. 1992, p. 678; Collar
et al
. 1994, p. 135; Conservation International 2007a, p. 1; del Hoyo
et al
. 2003, p. 638; Höfling 2007, p. 1; The Nature Conservancy 2007, p. 1; Sick 1993, p. 407; World Wildlife Fund 2007, pp. 3-51). Based on a number of recent estimates, 92 to 95 percent of the area (over 1,250,000 km
2
(482,628 mi
2
)) historically covered by tropical forests within the Atlantic Forest biome has been converted or severely degraded as a result of various human activities (Butler 2007, p. 2; Conservation International 2007a, p. 1; Höfling 2007, p. 1; IUCN 1999; Morellato and Haddad 2000, p. 786; Myers
et al
. 2000, pp. 853-854; The Nature Conservancy 2007, p. 1; Saatchi
et al
. 2001, p. 868; World Wildlife Fund 2007, pp. 2-41). The current rate of habitat decline within the Atlantic Forest biome is unknown.

In addition to the overall loss and degradation of native habitat within this biome, the remaining tracts of habitat are severely fragmented. The region has the two largest cites in Brazil, São Paulo and Rio de Janeiro, and is home to approximately 70 percent of Brazil's 169 million people (CEPF 2002; IBGE 2007). The major human activities that have resulted in the loss, degradation, and fragmentation of native habitats within the Atlantic Forest biome include extensive establishment of agricultural fields (
e.g.
, soy beans, sugarcane, and corn), plantations (
e.g.
, eucalyptus, pine, coffee, cocoa, rubber, and bananas), livestock pastures, centers of human habitation, and industrial developments (
e.g.
, charcoal production, steel plants, and hydropower reservoirs). Forestry practices (
e.g.
, commercial logging), subsistence activities (
e.g.
, fuelwood collection), and changes in fire frequencies also contribute to the degradation of the native habitat (BLI 2003a, p. 4; Júnior
et al
. 1995, p. 147; The Nature Conservancy 2007, p. 2; Nunes and Kraas 2000, p. 44; Peixoto and Silva 2007, p. 5; Saatchi
et al
. 2001, pp. 868-869; Scott and Brooke 1985,

p. 118; World Wildlife Fund 2007, pp. 3-51).

The fringe-backed fire-eye is not strictly tied to primary forest habitats and can make use of early-successional, secondary-growth forests with dense understory vegetation (BLI 2007e, p. 2; Collar
et al
. 1992, p. 677; del Hoyo
et al
. 2003, p. 637). However, this does not necessarily lessen the risk to the species from the effects of deforestation and habitat degradation. Atlantic Forest birds, such as the fringe-backed fire-eye, which are tolerant of secondary-growth forests, are also rare or have severely restricted ranges (
i.e.
, less than 21,000 km
2
(8,100 mi
2
)). Thus habitat degradation can adversely impact such species as equally as it impacts primary forest-obligate species (Harris and Pimm 2004, pp. 1612-1613). The entire range of the fringe-backed fire-eye encompasses approximately 4,990 km
2
(1,924 mi
2
), with only 20 percent of this area considered occupied (BLI 2007e, pp. 1-4).

The susceptibility to extirpation of limited-range species that are tolerant of secondary-growth forests or other disturbed sites can occur for a variety of reasons, such as when a species' remaining population is already too small or its distribution too fragmented such that it may not be demographically or genetically viable (Harris and Pimm 2004, pp. 1612-1613). In addition, while the fringe-backed fire-eye may be tolerant of secondary-growth forests or other disturbed sites, these areas may not represent optimal conditions for the species, which would include dense understories and abundant prey species. For example, management of plantations often involves intensive control of the site's understory vegetation and long-term use of pesticides, which eventually result in severely diminished understory cover and potential prey species (Rolim and Chiarello 2004, pp. 2687-2691; Saatchi
et al
. 2001, pp. 868-869; Scott and Brooke 1985, p. 118). Such management practices eventually result in the loss of native understory plant species, creating relatively open understories, which the fringe-bac

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3AE9-18691. Public record. Not legal advice.