90-Day Finding on Petition to List Chinook Salmon in the Klamath River Basin

On November 2, 2017, NOAA Fisheries received a petition to list the Upper Klamath-Trinity River Chinook salmon Evolutionarily Significant Unit (ESU) or, alternatively, to create a new ESU to describe Klamath spring-run Chinook salmon and list the new ESU under the Endangered Species Act (ESA).

NOAA Fisheries has reviewed this petition and determined that it presents substantial scientific or commercial information such that listing may be warranted. We are soliciting scientific and commercial information pertaining to the status of Chinook salmon in the Klamath Basin to ensure our review is comprehensive and informed by the most up-to-date information. NOAA Fisheries will conclude this status review by November 2, 2018.

What exactly does it mean that this “listing may be warranted?”

NOAA Fisheries has determined that the petitioners presented substantial scientific information to warrant additional review of the species’ status. It does not mean that we have already concluded that Upper Klamath-Trinity River Chinook salmon or, alternatively, Klamath spring-run Chinook salmon should or will be listed under the ESA. Rather, it means that we will proceed to collect and review scientific and commercial information to inform a decision as to whether listing of either ESU is warranted.

What information did NOAA Fisheries consider in deciding whether to conduct a comprehensive review?

In considering the petition to list Upper Klamath-Trinity River Chinook salmon or, alternatively, Klamath spring-run Chinook salmon, we evaluated the request based upon the information in the petition and any information readily available in our agency's files. NOAA Fisheries did not conduct additional research or solicit information from parties outside of the agency.

What is the timing of the comprehensive review?

The ESA requires that NOAA Fisheries conclude a status review within 12 months of receiving a listing petition (i.e., by November 2, 2018), and determine whether listing of the species is warranted.

What criteria will NOAA Fisheries use to evaluate whether ESA listing is warranted?

Section 4(b)(1)(A) of the ESA requires listing determinations based solely on the best scientific and commercial data available. Following a review of the status of the species and taking into account efforts being made to protect the species, NOAA Fisheries must determine whether a species is threatened or endangered as a result of one or a combination of the following factors:

• the present or threatened destruction, modification, or curtailment of its habitat or range;
• overutilization for commercial, recreational, scientific, or educational purposes;
• disease or predation;
• inadequacy of existing regulatory mechanisms; and/or
• other natural or man-made factors affecting its continued existence.

What are the next steps if NOAA Fisheries determines that ESA listing is warranted?

At the conclusion of our review, if NOAA Fisheries determines that listing is warranted, a proposed rule would be issued and
public comments would be solicited on the proposed determination. If in the 12-month finding NOAA Fisheries determines
that listing is not warranted, that determination would be published at that time.

Has NOAA Fisheries ever been petitioned to list Upper Klamath-Trinity River Chinook before?

Yes, we received and evaluated a similar petition on January 28, 2011 (76 FR 20302). After careful consideration of the best
scientific and commercial data available, ongoing conservation efforts, and the ESA section 4(a)(1) factors (described above)
we determined that the petitioned request was not warranted (77 FR 19597).

What’s the difference between a “species” and an “ESU”?

The ESA defines “species” to include any “distinct population segment of any species of vertebrate fish or wildlife which
interbreeds when mature.” A 1991 NOAA Fisheries policy established that a salmon stock is considered a distinct population,
and hence a “species” under the ESA, if it represents an evolutionary significant unit (ESU) of the biological species. The
stock must satisfy two criteria to be considered an ESU: (1) it must be substantially reproductively isolated from other
nonspecific population units; and (2) it must represent an important component in the evolutionary legacy of the species.

Why are spring-run and fall-run Chinook salmon currently considered to be part of the same ESU in the Upper Klamath-
Trinity River?

Salmon populations are arranged hierarchically, from individuals, to populations, to ESUs, and up to the entire
species. NMFS did recognize genetic differences between spring and fall Chinook in both the Trinity River and in the (Cal)
Salmon River during our 2011 status review. However, the BRT concluded that those differences did not alter our previous
conclusions that the spring and fall chinook constitute a single ESU configuration.

Literature Cited

Prince, Daniel J., Sean M. O'Rourke, Tasha Q. Thompson, Omar A. Ali, Hanna S. Lyman, Ismail K. Saglam, Thomas J.
Hotaling, Adrian P. Spidle, and Michael R. Miller. 2017. The Evolutionary Basis of Premature Migration in Pacific
Salmon Highlights the Utility of Genomics for Informing Conservation. Science Advances. 3(8): e1603198