# 50 C.F.R. § 17.80 (2026): Definitions

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_80

## Section

- **Citation:** 50 C.F.R. § 17.80 (2026)
- **Heading:** Definitions
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Title 50 CFR: Wildlife and Fisheries / Chapter I: UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR / Part 17: ENDANGERED AND THREATENED WILDLIFE AND PLANTS / Subpart H: Experimental Populations / § 17.80: § 17.80   Definitions.

## Text

(a) The term
experimental population
means an introduced and/or designated population (including any offspring arising solely therefrom) that has been so designated in accordance with the procedures of this subpart but only when, and at such times as, the population is wholly separate geographically from nonexperimental populations of the same species. Where part of an experimental population overlaps with nonexperimental populations of the same species on a particular occasion, but is wholly separate at other times, specimens of the experimental population will not be recognized as such while in the area of overlap. That is, experimental status will be recognized only outside the areas of overlap. Thus, such a population will be treated as experimental only when the times of geographic separation are reasonably predictable, e.g., fixed migration patterns, natural or manmade barriers. A population is not treated as experimental if total separation will occur solely as a result of random and unpredictable events.
(b) The term
essential experimental population
means an experimental population whose loss would be likely to appreciably reduce the likelihood of the survival of the species in the wild. All other experimental populations are to be classified as
nonessential.
[49 FR 33893, Aug. 27, 1984, as amended at 88 FR 42651, July 3, 2023]

## Nearby sections

- [50 C.F.R. § 17.80 (2026) § 17.80   Definitions.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_80.md)
- [50 C.F.R. § 17.81 (2026) § 17.81   Listing.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_81.md)
- [50 C.F.R. § 17.82 (2026) § 17.82   Prohibitions.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_82.md)
- [50 C.F.R. § 17.83 (2026) § 17.83   Interagency cooperation.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_83.md)
- [50 C.F.R. § 17.84 (2026) § 17.84   Species-specific rules—vertebrates.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_84.md)
- [50 C.F.R. § 17.85 (2026) § 17.85   Species-specific rules—invertebrates.](https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_85.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/CFR_T50_P17_S17_80. Check the current official text before relying on it. Not legal advice.