Endangered and Threatened Species; Proposed Threatened Status for the Gulf of Maine Population of Harbor Porpoise

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 227

[Docket No. 921232-2332; I.D. 092192B]

Endangered and Threatened Species; Proposed Threatened Status for

the Gulf of Maine Population of Harbor Porpoise

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and

Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; reopening of comment period.

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SUMMARY: National Marine Fisheries Service (NMFS) is reopening the

comment period on the proposed rule to list the Gulf of Maine/Bay of

Fundy (GOM/BOF) harbor porpoise, (Phocoena phocoena), as a threatened

species under the Endangered Species Act (ESA). Due to the passage of

time since the close of the previous comment period, the availability

of new/additional information and the desire to review the best

scientific information available during the decision-making process,

the comment period is being reopened.

DATES: Comments must be received by November 23, 1998.

ADDRESSES: Comments, requests for copies of this notice or a complete

list of references should be addressed to the Chief, Marine Mammal

Division (PR2), Office of Protected Resources, National Marine

Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910.

FOR FURTHER INFORMATION CONTACT: Margot Bohan, F/PR2, NMFS, (301) 713-

2322, Laurie Allen, Northeast Region, NMFS, (978) 281-9291, or Kathy

Wang, Southeast Region, NMFS, at (727) 570-5312.

SUPPLEMENTARY INFORMATION:

Background

On January 7, 1993, NMFS published a proposed rule (with a 90-day

comment period) to list the GOM population of harbor porpoise as

threatened under the ESA (58 FR 3108). The listing was proposed in

response to an ESA petition submitted by the Sierra Club Legal Defense

Fund, on behalf of the International Wildlife Coalition and 12 other

organizations (notice of receipt of petition to list published on

December 13, 1991 (56 FR 65044). It was also based on NMFS' research

findings at the time, which demonstrated that (a) the rate of bycatch

of harbor porpoise in commercial gillnet fisheries (extending from the

Bay of Fundy, Canada, south throughout the Gulf of Maine) might reduce

this population to the point where it would become threatened

throughout all or a portion of its range and that (b) there were no

regulatory measures in place to reduce this bycatch.

Following publication of the proposed rule, NMFS received several

comments requesting that public hearings be held throughout New

England. In response to these requests, NMFS extended the comment

period on the proposed rule until August 7, 1993 (58 FR 17569, April 5,

1993).

During the extended comment period, NMFS completed analyses of

sighting data from the 1992 porpoise abundance surveys and analyses of

the 1992 observer data used to determine total estimated bycatch in the

GOM gillnet fishery. These data were presented and discussed at a

meeting of the New England Fishery Management Council (NEFMC)

Groundfish Committee, Harbor Porpoise Subgroup, on June 16, 1993. After

the Harbor Porpoise Subgroup meeting, NEFMC forwarded comments to NMFS

requesting a 6-month extension of the final decision-making period on

the proposed rule to

[[Page 56597]]

list harbor porpoise. An extension was believed to be appropriate

because, according to the NEFMC and others present at the June 16

meeting, the data presented by NMFS cast doubt on whether the GOM/BOF

porpoise population was distinct and, thus, was a species under the

ESA.

Under section 4 of the ESA, if there is a substantial disagreement

regarding the sufficiency or accuracy of the available data relevant to

the determination or revision concerned, NMFS may extend the 1-year

period of determination. On November 8, 1993 (58 FR 59230),in

accordance with this provision, the date for the final determination on

the proposal was extended for 6 months to allow for further review of

the bycatch trend, analysis of the 1993 bycatch data prior to final

determination, and further consideration of all data, including the

abundance survey data, relevant to the final determination. NMFS

reopened the comment period for an additional 30 days following

completion of these analyses (59 FR 36158, July 15, 1994) to close on

August 11, 1994.

In the meantime, the New England Harbor Porpoise Working Group

(HPWG) met on July 21, 1994, to discuss the 1992 bycatch data under

consideration with regard to the ESA listing proposal. The HPWG, formed

in 1990, was a group of fishermen, environmentalists, and scientists

whose purpose was to define the extent of the harbor porpoise problem

and to identify solutions to reduce the incidental take of harbor

porpoise in gillnets while minimizing the impacts on the fishery. The

HPWG recommended that the updated bycatch estimates should be more

fully explained so that public review and comment could provide more

meaningful input to NMFS prior to the final listing determination. NMFS

prepared a document in August 1994 that addressed HPWG concerns. Given

that the comment period on the proposed listing was scheduled to close

on August 11, 1994, and that this would not allow enough time for

public review of the NMFS document regarding HPWG concerns, the comment

period on the proposed rule was further extended until September 11,

1994 (59 FR 41270). NMFS had not yet made a final determination when,

in fiscal year 1996, Congress imposed a 1-year moratorium on listing

species under the ESA.

The Agency has not yet issued a final determination. The final

determination will need to consider new population abundance and

bycatch data, NEFMC/NMFS' ongoing fishery management efforts to reduce

harbor porpoise bycatch, and the progress expected through the Marine

Mammal Protection Act (MMPA) Section 118 Take Reduction Team process.

Since publication of the proposed rule, the following information has

become available to supplement our understanding of the species' status

and factors affecting the species.

Stock Definition and Geographic Range Data

Recent analyses involving mitochondrial DNA (Wang, 1996),

organochlorine contaminants (Westgate, 1997), heavy metals (Johnston,

1995), and life history parameters (Read and Hohn, 1995) support the

currently accepted hypothesis that there are four separate populations

in the western North Atlantic: the Gulf of Maine/Bay of Fundy, Gulf of

St. Lawrence, Newfoundland, and Greenland populations.

Abundance Data

Three abundance surveys were conducted during the summers of 1991,

1992, and 1995. The population estimates were 37,500 harbor porpoises

in 1991 (coefficient of variation (CV) = 0.29, 95% confidence interval

(CI) = 26,700-86,400) (Palka, 1995a), 67,500 harbor porpoises in 1992

(CV = .23, 95 percent CI = 32,900-104,600) (Palka, 1996), and 74,000

harbor porpoises in 1995 (CV = 0.20, 95 percent CI = 40,900-109,100)

(Palka, 1996). The inverse variance weighted-average abundance estimate

was 54,300 harbor porpoises (CV = 0.14, 95 percent CI = 41,300-71,400).

Possible reasons for inter-annual differences in abundance and

distribution include experimental error and inter-annual changes in

water temperature and availability of primary prey species (Palka,

1995b).

Population Viability Analysis

Several recent analyses have concluded, using various measures,

that the current level of mortality/bycatch of GOM/BOF harbor porpoise

is too high. Current bycatch/mortality levels exceed the calculated PBR

for the population, which is why the population has been designated as

``strategic'' under the MMPA. Additionally, a recent uncertainty

analysis (Caswell et al., In press) concluded that current rates of

bycatch/mortality are a threat to the GOM/BOF harbor porpoise

population. Neither of these analyses, however, directly calculates the

risk of extinction to the population that is relevant for consideration

of listing under the ESA. To directly examine the potential risk of

extinction of GOM/BOF harbor porpoise, a population viability analysis

(PVA) was recently prepared (Preliminary analyses, PR2 draft report). A

PVA is used to estimate future trends of a population to estimate the

probability of extinction of the population given certain assumptions.

Using 1991, 1992, and 1995 abundance data and 1992-1996 bycatch data,

stochastic population dynamics models of the GOM/BOF harbor porpoise

population were developed to evaluate the probability of persistence of

the population over the foreseeable future (the next 20 to 100 years).

Each of the models predicted a very high probability of extinction

within 100 years under the current levels of mortality/bycatch, whereas

the probability of extinction within 20 years was estimated to be low.

Reducing the current mortality/bycatch level by one-half would

decrease, but not eliminate, the probability of extinction in 100

years, but was estimated to eliminate any probability of extinction

within 20 years. Finally, reducing the current mortality/bycatch to

one-quarter of the current level was estimated to make the risk of

extinction within 100 years very low.

Supplemental Summary of ESA Factors Affecting the Species

Species may be determined to be threatened or endangered due to one

or more of five factors described in section 4(a)(1) of the ESA. These

factors are discussed here, as they apply to the GOM/BOF harbor

porpoise in light of additional/new information that has become

available since the species was originally proposed for listing. This

information is intended to supplement the information on the status of

the species contained in the proposed rule.

A. The Present or Threatened Destruction, Modification, or Curtailment

of Habitat or Range

Although the shoreline bordering the nearshore habitat of this

species along the eastern U.S. coastline is developed in many areas and

is potentially threatened with further destruction or physical

modification, there is no new/additional evidence to indicate that such

modification or destruction has contributed to a decline of this

population or that the range of this species has changed significantly

as a result of habitat loss. This factor was not a basis for the

proposed listing.

B. Overutilization for Commercial, Recreational, Scientific, or

Educational Purposes

One of the principal factors for proposing to list the GOM/BOF

population of harbor porpoise as

[[Page 56598]]

threatened under the ESA was the level of harbor porpoise bycatch in

commercial fisheries in the GOM/Bay of Fundy/Mid-Atlantic. GOM/BOF

harbor porpoise takes have been documented in the U.S. New England

multispecies sink gillnet, Mid-Atlantic coastal gillnet, and Atlantic

pelagic drift gillnet fisheries, and in the Canadian Bay of Fundy sink

gillnet fishery and herring weir fishery. The average annual mortality

estimate from 1992 to 1996 for the above U.S. fisheries is 1,667 (CV =

0.09) harbor porpoise. The average annual mortality estimate in Canada

from 1993 to 1996 is 162 harbor porpoise.

Recent data on incidental takes in U.S. fisheries are available

from observer programs monitoring the New England multispecies sink

gillnet fishery, U.S. Atlantic coastal gillnet fisheries, the Atlantic

pelagic drift gillnet fishery, the North Atlantic bottom trawl fishery,

Canada's Bay of Fundy sink gillnet fishery, and Canada's herring

fishing weirs.

New England multispecies sink gillnet fishery: Most of the harbor

porpoise takes in U.S. fisheries are from the New England multispecies

sink gillnet fishery. In 1990, NMFS started an observer program to

investigate marine mammal takes in this fishery. Between 1990 and 1996,

362 harbor porpoise mortalities related to this fishery were observed.

In 1993, there were approximately 349 full and part-time vessels in the

New England multispecies sink gillnet fishery, which covered the Gulf

of Maine and southern New England. An additional 187 vessels were

reported to occasionally fish in the Gulf of Maine with gillnets for

bait or personal use; however, these vessels were not covered by the

observer program (Walden, 1996) and their fishing effort was not used

in estimating mortality. Observer coverage in terms of trips has been

1, 6, 7, 5, 7, 5, and 4 percent for years 1990 to 1996, respectively.

Annual estimates of harbor porpoise by-catch in the New England

multispecies sink gillnet fishery reflect seasonal distribution of the

species and of fishing effort. By-catch estimates include a correction

factor for the under-recorded number of by-caught animals that occurred

during unobserved hauls on trips with observers on the boat, when

applicable. Need for such a correction became evident following a 1994

re-analysis of data from the sea sampling program indicating that, for

some years, by-catch rates from unobserved hauls were lower than for

observed hauls (Palka, 1994; CUD, 1994; and Bravington and Bisack,

1996). These revised by-catch estimates replace those published earlier

(Smith et al., 1993). These estimates remain negatively biased because

they do not include harbor porpoises that may have fallen out of the

net while still underwater. This bias cannot be quantified at this

time. Estimated annual by-catch (CV in parentheses) from this fishery

during 1990-1996 was 2,900 in 1990 (0.32), 2,000 in 1991 (0.35), 1,200

in 1992 (0.21), 1,400 in 1993 (0.18) (Bravington and Bisack 1996; CUD

1994), 2100 in 1994 (0.18), 1400 in 1995 (0.27) (Bisack, 1997a), and

1200 (0.23) in 1996. Average estimated harbor porpoise mortality and

serious injury in the New England multispecies sink gillnet fishery

during 1992-1996 was 1,460 (0.10).

Differential mortality by age or sex in animals collected before

1994 was not evident in U.S. or Canadian gillnet fisheries; no pattern/

propensity could be discerned based on available data. In addition,

substantial inter-annual variation in the age and sex composition of

the by-catch existed (Read and Hohn, 1995). However, with a larger

sample, from the harbor porpoises that were examined by necropsy or

from tissues received from sea sampling observers (n=171 between 1989

and 1997), the sex ratio is now 0.34 females per male (A. Read, pers.

comm.). Investigations are currently underway to determine spatial-

temporal patterns in the sex ratio.

Two preliminary experiments, using acoustic alarms (pingers)

attached to gillnets, that were conducted in the Gulf of Maine during

1992 and 1993 took 10 and 33 harbor porpoises, respectively. During

fall 1994, a controlled scientific experiment was conducted in the

southern Gulf of Maine where all nets with and without active pingers

were observed (Kraus et al. 1997). In this experiment, 25 harbor

porpoises were taken in 423 strings with non-active pingers (controls),

and two harbor porpoises were taken in 421 strings with active pingers.

In addition, 17 other harbor porpoises were taken in nets with pingers

that were not in the experiment. During 1995 to 1996, experimental

fisheries were conducted where all nets in a designated area used

pingers and only a sample of the nets were observed. During November

through December 1995, the experimental fishery was conducted in the

southern Gulf of Maine (Jeffreys Ledge) region where no harbor

porpoises were observed taken in 225 pingered nets. During April 1996,

three other experimental fisheries occurred. In the Jeffreys Ledge

area, in 88 observed hauls using pingered nets, nine harbor porpoises

were taken. In the Massachusetts Bay region, in 171 observed hauls

using pingered nets, two harbor porpoises were taken. And, in a region

just south of Cape Cod, in 53 observed hauls using pingered nets, no

harbor porpoises were taken. All takes from pingered nets were added

directly to the estimated total bycatch for the rest of that year in

the rest of the fishery. As a result of seeming inconsistency in spring

results compared to fall results, the GOMTRT recommended an additional

scientific experiment in the spring of 1997. Again, there were similar

mean fish catch rates and similar numbers of seals caught between all

treatments; zero harbor porpoise were caught in nets with active

pingers, demonstrating that pingers reduced the incidental catch of

harbor porpoise in sink gillnets during spring (Kraus et al., 1997).

U.S. Mid-Atlantic coastal gillnet fisheries: In July 1993, an

observer program was initiated in the U.S. Atlantic coastal gillnet

fishery by the Northeast Fisheries Science Center (NEFSC) Sea Sampling

program. Twenty trips were observed during 1993. During 1994 and 1995,

221 and 382 trips were observed, respectively. This fishery, which

extends from North Carolina to the New York/Connecticut/Rhode Island

border, is actually a combination of small vessel fisheries that target

a variety of fish species, some of which operate right off the beach.

The number of vessels in this fishery is unknown because records which

are held by both state and Federal agencies have not been centralized

and standardized. Observer coverage, expressed as percent of tons of

fish landed, was 5 percent and 4 percent for 1995 and 1996. During 1995

and 1996, respectively, 6 and 19 harbor porpoises were observed taken.

During 1995 and 1996, observed fishing effort was concentrated off NJ

and scattered between DE and NC from 1 to 50 miles (1500 meters) off

the beach. All documented by-catches during 1995 and 1996 were from

January to April. By-catch estimates were determined by using methods

similar to that used for by-catch estimates in the New England

multispecies gillnet fishery (Bravington and Bisack, 1996; Bisack,

1997a). Using the observed takes, the estimated annual mortality (CV in

parentheses) attributed to this fishery was 103 (0.57) and 311 (0.31)

for 1995 and 1996, respectively. Average annual estimated harbor

porpoise mortality and serious injury from the Mid-Atlantic coastal

gillnet fishery during 1995 and 1996 was 207 (CV=0.27).

Atlantic pelagic drift gillnet fishery: One harbor porpoise was

observed taken from the 1991-1996 Atlantic pelagic

[[Page 56599]]

drift gillnet fishery. Although the estimated total number of hauls in

this fishery increased from 714 in 1989 to 1,144 in 1990, effort was

severely reduced, thereafter, with the introduction of quotas.

Observer coverage, expressed as percent of sets observed was 8

percent in 1989, 6 percent in 1990, 20 percent in 1991, 40 percent in

1992, 42 percent in 1993, 87 percent in 1994, 99 percent in 1995, and

64 percent in 1996. (The decline in observer coverage in 1996 is

attributable to trips made by vessels that were deemed unsafe (size/

condition) for observers.) Estimates of the total by-catch, for each

year from 1989 to 1993, were obtained using the aggregated (pooled

1989-1993) catch rates, by strata (Northridge, 1996). Estimates of

total annual by-catch for 1994, 1995, and 1996 were estimated from the

sum of the observed caught and the product of the average by-catch per

haul and the number of unobserved hauls as recorded in logbooks.

Variances were estimated using bootstrap re-sampling techniques

(Bisack, 1997b). Estimated annual fishery-related mortality (CV in

parentheses) attributable to this fishery was 0.4 in 1992 (1.00), 1.5

in 1993 (0.34), 0 in 1994, and 0 in 1996. The average estimated harbor

porpoise mortality and serious injury in the Atlantic pelagic drift

gillnet fishery during 1992-1996 was 0.4 (0.34) (Waring et al., in

review).

North Atlantic bottom trawl fishery: One harbor porpoise was

observed incidentally captured in the North Atlantic bottom trawl

fishery between 1989 and 1996. The animal was clearly dead prior to

being taken by the trawl because it was severely decomposed and the tow

duration of 3.3 hours was insufficient to allow extensive

decomposition; therefore, there is no estimated by-catch for this

fishery (Waring et al., in review).

Canadian Bay of Fundy sink gillnet fishery: During the 1980s, total

harbor porpoise by-catch in the Canadian Bay of Fundy sink gillnet

fishery was thought to be low, based on casual observations and

discussions with fishermen. The estimated harbor porpoise by-catch in

1986 was 94 to 116, and, in 1989, it was 130 (Trippel et al., 1996).

The Canadian gillnet fishery occurs mostly in the western portion of

the Bay of Fundy during the summer and early autumn months when the

density of harbor porpoises is the highest. Polacheck (1989) reported

there were 19 gillnetters active in 1986; 28 active in 1987; and 21 in

1988.

More recently, an observer program implemented in the summer of

1993 provided a total by-catch estimates of 424 harbor porpoises. No

measure of variability was estimated. The observer program was expanded

in 1994, and the by-catch was estimated to be between 80 and 120 harbor

porpoises where the fishing fleet consisted of 28 vessels (Trippel et

al., 1996). During 1995, due to groundfish quotas being exceeded, the

gillnet fishery was closed during July 21 to August 31, 1995. During

the open fishing period of 1995, 89 percent of the fishing trips were

observed, all in the Swallowtail region. Approximately 30 percent of

these observed trips used pingered nets. The estimated by-catch was 87

harbor porpoises (Trippel et al., 1996). No confidence interval was

able to be computed due to lack of coverage in the Wolves fishing

grounds. During 1996, the Canadian gillnet fishery was closed from

August 20 to September 30, 1996. Preliminary estimates of by-catch from

1996 were in the range of 20 to 50 harbor porpoises. By-catch estimates

are currently not available for the 1997 observer program.

Canadian herring fishing weirs: Harbor porpoise takes have been

observed in Canadian fishing weirs, though not in U.S. fishing weirs.

However, no program has been set up to observe U.S. fishing weirs. In

the Bay of Fundy, weirs are presently operating from May to September

each year. Weirs are found along the southwestern shore of the Bay of

Fundy and scattered along the western Nova Scotia and northern Maine

coasts. There were 180 active weirs in the western Bay of Fundy and 56

active weirs in Maine in 1990 (Read, 1994). It is unknown how many

herring weirs currently exist in U.S. and Canadian waters. Smith et al.

(1983) estimated that approximately 70 harbor porpoises become trapped

annually, an average of 27 die, and the rest are released alive. At

least 43 harbor porpoises were trapped in Bay of Fundy weirs in 1990,

but the number killed is unknown. In 1993, after a cooperative program

between fishermen and Canadian biologistsbegan, over 100 harbor

porpoises were released alive, and an unknown number died (Read, 1994).

C. Disease or Predation

There continues to be no indication, from stranding data or tissue

analyses, that disease has had a measurable impact on GOM/BOF harbor

porpoise. Likewise, there is no new evidence, since the proposed

listing, to indicate that predation has contributed to the decline of

GOM/BOF porpoise. This particular factor was not a basis for the

proposed listing.

D. The Inadequacy of Existing Regulatory Mechanisms

This factor and Factor B formed the basis for the proposed listing.

Discussed here in chronological order of implementation are the

regulatory mechanisms that have gone into effect since publication of

the proposed rule. In addition, those proposed regulations that may go

into effect in the near future through the MMPA Section 118 Take

Reduction Team process are described.

Management Actions Since the Proposed Listing

In 1994, as part of Amendment 5 to the Northeast Multispecies

Fishery Management Plan (NE Multispecies FMP), the NEFMC proposed,under

authority of the Magnuson Fishery Conservation and Management Act (16

U.S.C. 1801 et seq.) a 4-year program to reduce the harbor porpoise

bycatch off New England to 2 percent of the estimated harbor porpoise

population size per year. To achieve this goal, the NEFMC recommended

phasing in time and area closures to sink gillnet gear, such that take

levels would be reduced by 20 percent each year over the 4-year period.

NMFS adopted and implemented NEFMC's first-year closure recommendations

on May 25, 1994 (59 FR 26972).

In the fall of 1994, NMFS authorized and provided support for a

cooperative experiment by New England gillnet fishermen and for

scientists to develop methods to deter harbor porpoise away from

fishing nets. Building on work in previous years, the experiment sought

to evaluate the effectiveness of acoustic deterrent devices or

``pingers'' attached to gillnets to prevent entanglement of harbor

porpoise. The experiment was conducted in the Mid-Coast Closed Area

(closed under Amendment 5 to the NE Multispecies FMP) off the New

Hampshire-Massachusetts border. The result of that experiment showed

that pingers can reduce the bycatch of porpoise substantially during

the fall in this area (Kraus et al., 1995).

Harbor porpoise bycatch rates increased in 1994 despite the new

time-area gillnet fishing closures enacted by NMFS on May 25, 1994. The

increased rate occurred before the fall area closure and occurred in

waters that are adjacent to the closure area, in an area known as

Jeffreys ledge. Based on this information, the NEFMC recommended

expanding both the time and area of the fall closure around Jeffreys

ledge. NMFS adopted a rule to do so on October 30, 1995 (60 FR 57207).

In November 1995, NMFS adopted NEFMC's recommendations to expand

[[Page 56600]]

the closures contained in Framework Adjustment 4 to the NE Multispecies

FMP for sink gillnet gear by implementing Framework Adjustment 14 (60

FR 55207). Framework 14 enlarged and redefined the Mid-Coast Closure

Area in both time and area during 1995 in an effort to achieve the

necessary reductions in harbor porpoise bycatch. The Mid-Coast closure

was closed to fishing with sink gillnets from March 25 through April

25. Framework Adjustment 14 also required closure of an area in

southern New England, south of Cape Cod, from March 1 to 30.

Amendment 7 to the NE Multispecies FMP, implemented in July 1996,

included a revised objective to address new provisions in the MMPA (61

FR 27709). With Amendment 7, NMFS adopted and implemented NEFMC's

recommendations concerning marine mammal gillnet closures as additional

groundfish conservation closures for all types of gear other than

gillnets capable of catching multispecies, as part of an overall

groundfish effort reduction program. In addition, the NEFMC recommended

the use of pingers in several experimental fisheries to evaluate their

use as bycatch reduction tools.

In February 1996, NMFS convened the Gulf of Maine Take Reduction

Team (GOMTRT) to develop a plan to reduce the incidental take of harbor

porpoise in sink gillnets (61 FR 5384). The 1994 amendments to the MMPA

require the preparation and implementation of Take Reduction Plans

(TRPs) for certain marine mammals stocks. The GOMTRT convened with the

understanding that a separate take reduction team would meet to address

the harbor porpoise bycatch problem in the Mid-Atlantic. The GOMTRT

included representatives of the Northeast multispecies sink gillnet

fishery, NMFS, state marine resource management agencies, NEFMC,

environmental organizations, and academic and scientific organizations.

The environmental organizations included the Center for Marine

Conservation and the Humane Society of the United States. The GOMTRT

met five times between February and July 1996 and submitted a consensus

draft TRP to NMFS in August of 1996.

A proposed rule to implement the GOMTRP was published on August 13,

1997 (62 FR 43302). The proposed rule would outline a schedule of time/

area closures and periods during which acoustic deterrents or

``pingers'' would be required for each of the established management

areas.

NMFS convened the Mid-Atlantic Take Reduction Team (MATRT) on

February 25, 1997, to address the interactions between strategic marine

mammal stocks and the Mid-Atlantic coastal gillnet fisheries (62 FR

8428). The MATRT met five times between January 1997 and August 1997

and delivered a draft report to NMFS on August 23, 1997. The MATRT

report consists of the take reduction measures, both regulatory and

non-regulatory, which the MATRT agreed to by consensus, and a

discussion of several non-consensus issues. Because the MATRT did not

reach consensus on the use of a pinger experiment in the Mid-Atlantic,

it was not able to deliver a consensus TRP to NMFS.

NMFS re-convened the GOMTRT in December 1997 to evaluate new

bycatch data that had become available since the GOMTRP was proposed by

NMFS (62 FR 65402). The new bycatch data suggested that the measures

proposed under the August 13 GOMTRP proposed rule would not be

sufficient to achieve potential biological removal (PBR) for harbor

porpoise. NMFS reopened the public comment period on the proposed rule

for 1-month during the deliberations of the GOMTRT. At the December

meeting, the GOMTRT developed new recommendations and agreed on a

number of additional measures for bycatch reduction that were presented

to NMFS in the form of a report on January 14, 1998 (RESOLVE, 1998).

Framework 25 to the NE Multispecies FMP (63 FR 15326, March 31,

1998), was implemented on May 1, 1998. Framework 25 implements gillnet

fishing closures throughout the GOM to conserve cod (Gadus morhua).

Framework 25 implements management measures that include 1-month

sequential closures for each of four Gulf of Maine inshore areas

starting in Massachusetts Bay and extending to Penobscot Bay and for an

offshore area comprising Cashes Ledge; a year-round closure

encompassing parts of Stellwagen Bank, Jeffreys Ledge, and Wildcat

Knoll; and a reduction in the Gulf of Maine cod landing limit.

On September 11, 1998 (63 FR 48670), NMFS proposed a Harbor

Porpoise Take Reduction Plan (HPTRP) to replace the GOMTRP proposed on

August 13, 1997. The GOMTRP is proposed to be replaced due to three

developments. First, new bycatch information became available which

indicates that significant changes to the August 13 GOMTRP are needed

to achieve the PBR level for harbor porpoise. Second, some of the cod

fishery closures under Framework 25 are expected to indirectly provide

harbor porpoise conservation. Third, the MATRT submitted its report to

NMFS which presented new information on the level of harbor porpoise

bycatch in the Mid-Atlantic region. The combination of these actions

led NMFS to integrate the initially separate plans into one

comprehensive TRP and to replace the GOMTRP proposed rule.

The proposed HPTRP would require a wide range of management

measures to reduce the bycatch and mortality of harbor porpoise. In the

Gulf of Maine, the proposed HPTRP included time and area closures and

time/area periods during which pinger use would be required in the

Northeast, Mid-coast, Massachusetts Bay, Cape Cod south and Offshore

Closure Areas. In the Mid-Atlantic area, the proposed HPTRP included

time/ area closures and modifications to gear characteristics. NMFS

expects that the proposed HPTRP will reduce bycatch to the PBR level.

NMFS intends to issue a final rule to implement the HPTRP on or

about December 1, 1998.

E. Other Natural or Manmade Factors Affecting its Continued Existence

Sixty-four harbor porpoise strandings were reported from Maine to

North Carolina between January and June 1993. Fifty of those harbor

porpoise were reported stranded in the U.S. Atlantic region from New

York to North Carolina between February and May. Many of the carcasses

recovered in this area during this time period had cuts and body damage

suggestive of net marking (Haley and Read, 1993). Five out of eight

carcasses and fifteen heads from the strandings that were examined

showed signs of human interactions (net markings on skin and missing

flippers or flukes). Decomposition of the remaining animals prevented

determination of the cause of death. Earlier reports of harbor porpoise

entangled in gillnets in the Chesapeake Bay and along the New Jersey

coast and reports of apparent mutilation of harbor porpoise carcasses

raised concern that the 1993 strandings were related to a coastal net

fishery, such as the American shad coastal gillnet fishery (Haley and

Read, 1993).

Between 1994 and 1996, 107 harbor porpoise carcasses were recovered

from beaches in Maryland, Virginia, and North Carolina. Only juvenile

harbor porpoises were present in this sample. Of the 40 harbor

porpoises for which cause of death could be established, 25 displayed

definitive evidence of entanglement in fishing gear. In four cases, it

was possible to determine that the animal was entangled in monofilament

nets (Cox et al., in press).

Stranding data may be misleading, however, because not all of the

marine

[[Page 56601]]

mammals that die or are seriously injured may wash ashore, nor will all

of those that do wash ashore necessarily show clear signs of the cause

of death. Finally, the level of technical expertise among stranding

network personnel varies widely as does the ability to recognize signs

that indicate the cause of death.

Other potentially human-induced factors that may be affecting this

harbor porpoise population include high levels of contaminants in their

tissues. Concentrations of organochlorine contaminants from 110 GOM/BOF

harbor porpoises were recently measured (Westgate, 1995).

Polychlorinated biphenyl (PCB) levels, the most prominent contaminant,

and dichloro-diphenyl trichloroethane (DDT) levels were both higher in

the Gulf of Maine/Bay of Fundy harbor porpoises than in the Gulf of St.

Lawrence and Newfoundland harbor porpoises, although they are now much

lower than that found in animals 10 years ago, as reported in Gaskin et

al. (1983). Trace metal contaminants were also measured, and it was

found that mean concentrations of copper, zinc, and mercury were

similar to values previously reported for harbor porpoises in other

regions of the world (Johnston, 1995). No obvious pathology has been

noted in more than 300 necropsies of harbor porpoises incidentally

captured in gillnets in the Bay of Fundy (A.J. Read, unpublished data).

Although it is not known whether these contaminants have other effects,

the presence of these contaminants in harbor porpoise tissues does not

appear to pose a serious threat to this population.

Critical Habitat

NMFS has not completed the analysis necessary for the designation

of critical habitat. A decision regarding critical habitat will be made

in a separate rulemaking, as warranted, in accordance with the final

listing determination.

Public Comments Solicited

Due to the availability of new/additional information, the passage

of time since the close of the previous comment period, and the desire

to review the best scientific information available during the

decision-making process, the public comment period for the proposed ESA

listing of GOM/BOF harbor porpoise as a threatened species is being

reopened. All comments will be considered in NMFS' final determination

(see DATES).

Authority: 16 U.S.C. 1531 et seq.

Dated: October 15, 1998.

Rolland A. Schmitten,

Assistant Administrator for Fisheries, National Marine Fisheries

Service.

[FR Doc. 98-28269 Filed 10-16-98; 4:35 pm]

BILLING CODE 3510-22-F