Endangered and Threatened Wildlife and Plants; Notice of 12-Month Finding on a Petition To Delist the Snake River Fall-Run Chinook Salmon Evolutionarily Significant Unit Under the Endangered Species Act (ESA), 33469-33480 [2016-12453]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 81, Number 102 (Thursday, May 26, 2016)]
[Notices]
[Pages 33469-33480]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-12453]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[Docket No. 150211136-6422-02]
RIN 0648-XD769


Endangered and Threatened Wildlife and Plants; Notice of 12-Month 
Finding on a Petition To Delist the Snake River Fall-Run Chinook Salmon 
Evolutionarily Significant Unit Under the Endangered Species Act (ESA)

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice of 12-month finding and availability of 5-year reviews.

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SUMMARY: We, NMFS, announce a 12-month finding on a petition to delist 
the Snake River fall-run Chinook salmon (Oncorhynchus tshawytscha) 
(Snake River fall-run Chinook) Evolutionarily Significant Unit (ESU) 
under the Endangered Species Act (ESA). The Snake River fall-run 
Chinook ESU was listed as threatened under the ESA in 1992. We have 
completed a comprehensive review of the status of the species in 
response to the petition. Based on the best scientific and commercial 
data available, we have determined that delisting of the Snake River 
fall-run Chinook ESU is not warranted at this time. We conclude that 
the Snake River fall-run Chinook is likely to become an endangered 
species within the foreseeable future throughout all or a significant 
portion of its range, and will remain listed as a threatened species 
under the ESA. We also announce the availability of 5-year reviews, 
prepared pursuant to ESA, for four Snake River salmonid species: The 
Snake River fall-run Chinook ESU, the Snake River sockeye salmon ESU, 
the Snake River spring/summer Chinook salmon ESU, and the Snake River 
steelhead distinct population segment (DPS). We combined our 
evaluations and findings for these four species into a joint report. 
This 5-Year Review Report determined that the four Snake

[[Page 33470]]

River salmon species, including the Snake River fall-run Chinook ESU, 
should retain their current listed status under the ESA.

DATES: This finding was made on May 26, 2016.

ADDRESSES: The documents informing the 12-month finding are available 
electronically at: https://www.westcoast.fisheries.noaa.gov/. You may 
also receive copies of these documents by submitting a request to the 
Protected Resources Division, West Coast Region, NMFS, 1201 NE Lloyd 
Boulevard, Suite 1100, Portland, OR 97232, Attention: Snake River fall-
run Chinook 12-month Finding.

FOR FURTHER INFORMATION CONTACT: Dr. Scott Rumsey, NMFS West Coast 
Region at (503) 872-2791; or Maggie Miller, NMFS Office of Protected 
Resources at (301) 427-8403.

SUPPLEMENTARY INFORMATION: 

Background

    The Snake River fall-run Chinook ESU was listed as threatened under 
the ESA in 1992 (57 FR 14658; April 22, 1992). We have twice affirmed 
that the Snake River fall-run Chinook ESU should remain classified as a 
``threatened'' species under the ESA following reviews of the species' 
status in 2005 (70 FR 37160; June 28, 2005) and again in 2011 (76 FR 
50448; August 15, 2011). On January 16, 2015, we received a petition 
from the Chinook Futures Coalition to delist the Snake River fall-run 
Chinook ESU under the ESA. Separately, on February 6, 2015, we 
published a notice of initiation of 5-year reviews, as required by ESA 
section 4(c)(2)(A), for 32 West Coast marine and anadromous ESA-listed 
species, including the Snake River fall-run Chinook ESU, and requested 
information from the public to inform our reviews (80 FR 6695; February 
6, 2015). On April 22, 2015, we published a positive 90-day finding (80 
FR 22468) that the Snake River fall-run Chinook ESU delisting petition 
presented substantial scientific or commercial information indicating 
that the petitioned action may be warranted. As required by ESA section 
4(b)(3)(A), our April 22, 2015 finding announced the initiation of a 
status review to determine whether the petitioned action was warranted 
and invited the public to submit scientific and commercial information 
to inform our review. We explained that any information submitted to 
inform the 5-year review for Snake River fall-run Chinook ESU would 
also be considered in making our 12-month finding for that species.

Listing Species Under the Endangered Species Act

    Section 3 of the ESA 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 one ``which is 
likely to become an endangered species within the foreseeable future 
throughout all or a significant portion of its range.'' To be 
considered for listing under the ESA, a group of organisms must 
constitute a ``species,'' which is defined in section 3 of the ESA to 
include ``any subspecies of fish or wildlife or plants, and any 
distinct population segment of any species of vertebrate fish or 
wildlife which interbreeds when mature.'' For identifying species of 
Pacific steelhead, we apply the joint NMFS-U.S. Fish and Wildlife 
Service (USFWS) Policy Regarding the Recognition of Distinct Vertebrate 
Population Segments under the Endangered Species Act (DPS Policy) (61 
FR 4722; February 7, 1996). Under the DPS Policy, we consider two 
elements in evaluating whether a vertebrate population segment 
qualifies as a DPS, and consequently a `species,' under the ESA: (1) 
Discreteness of the population segment in relation to the remainder of 
the species/taxon, and, if discrete; (2) the significance of the 
population segment to the species/taxon. For Pacific salmon, we apply 
our Policy on Applying the Definition of Species under the Endangered 
Species Act to Pacific Salmon (ESU Policy) in identifying species (56 
FR 58612; November 20, 1991). Per the ESU Policy, to qualify as a DPS, 
a Pacific salmon population or group of populations must be 
substantially reproductively isolated and represent an important 
component in the evolutionary legacy of the biological species. A 
population meeting these criteria is considered to be an 
``evolutionarily significant unit'' (ESU), and hence a ``species,'' 
under the ESA (56 FR 58612).
    Section 4(b)(1)(A) of the ESA requires NMFS to make listing 
determinations based solely on the best scientific and commercial data 
available after conducting a review of the status of the species and 
after taking into account efforts being made to protect the species. 
Section 4(a)(1) of the ESA and NMFS' implementing regulations (50 CFR 
part 424) also states that we must determine whether a species is 
endangered or threatened because of any one or a combination of the 
following five factors: (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) inadequacy of 
existing regulatory mechanisms; or (E) other natural or man-made 
factors affecting its continued existence. A species may be removed 
from the list if the Secretary of Commerce determines, based on the 
best scientific and commercial data available and after conducting a 
review of the species' status, that the species is no longer threatened 
or endangered because of one or a combination of the section 4(a)(1) 
factors. Pursuant to our regulations at 50 CFR 424.11(d), a species may 
be delisted only if such data substantiate that it is neither 
endangered nor threatened for one or more of the following reasons:
    (1) Extinction. Unless all individuals of the listed species had 
been previously identified and located, and were later found to be 
extirpated from their previous range, a sufficient period of time must 
be allowed before delisting to indicate clearly that the species is 
extinct.
    (2) Recovery. The principal goal of the ESA is to return listed 
species to a point at which protection under the ESA is no longer 
required. A species may be delisted on the basis of recovery only if 
the best scientific and commercial data available indicate that it is 
no longer endangered or threatened.
    (3) Original data for classification in error. Subsequent 
investigations may show that the best scientific or commercial data 
available when the species was listed, or the interpretation of such 
data, were in error.

ESA Section 4 Status Reviews

    Section 4(c)(2)(A) of the ESA requires that we conduct a review of 
the status of each listed species under our jurisdiction at least once 
every 5 years (5-year reviews). In conducting 5-year reviews, we 
consider the best scientific and commercial data available to determine 
whether any species should be: (1) Delisted; (2) changed in status from 
endangered to threatened; or (3) changed in status from threatened to 
endangered. On February 6, 2015, we published a notice of initiation of 
5-year reviews for West Coast ESA-listed species, including the Snake 
River fall- run Chinook ESU (80 FR 6695; February 6, 2015), and 
solicited information to inform the 5-year reviews during a 90-day 
public comment period.
    Section 4(b)(3) of the ESA requires that, when NMFS makes a 
positive 90-day finding on a petition to list or delist a species, we 
must promptly commence a review of the status of the species concerned. 
As part of our April 22,

[[Page 33471]]

2015, positive 90-day finding on the subject delisting petition, we 
announced the initiation of a status review of the Snake River fall-run 
Chinook ESU and solicited information to inform that review during a 
60-day public comment period (80 FR 22468). We explained in our April 
22, 2015 notice that we would consider all information received in 
response to either the 5-year review or positive 90-day finding 
requests for information in making our 12-month finding for Snake River 
fall-run Chinook ESU. In response to these requests for information, we 
received information from Federal and state agencies, Native American 
Tribes, conservation organizations, fishing and industry groups, and 
individuals. This information, as well as other information routinely 
collected by our agency, informed our status review of the Snake River 
fall-run Chinook ESU, as well as the 5-year reviews of the other Snake 
River species.
    To realize efficiencies and to ensure that our reviews were based 
on the best scientific and commercial information available, we 
integrated our section 4(b)(3)(B) status review and our section 
4(c)(2)(A) 5-year review of the Snake River fall-run Chinook ESU. We 
also consolidated our 5-year reviews of the four listed Snake River 
salmonid species into a joint report. We used a multi-step process to 
complete these reviews. First, scientists from our Northwest Fisheries 
Science Center collected and analyzed information about the viability 
of the Pacific Northwest salmon ESUs and steelhead DPSs undergoing 5-
year reviews, including the Snake River salmon ESUs and steelhead DPS. 
As part of Northwest Fisheries Science Center's review, the scientists 
also evaluated life-history, genetic, and other information that might 
inform a reconsideration of the delineation of the salmon ESUs and 
steelhead DPSs. At the end of this process, the Northwest Fisheries 
Science Center prepared a report detailing the results of their 
analyses (NWFSC 2015).
    Next, biologists from NMFS' West Coast Region with expertise in 
hatchery management conducted a review of all West Coast salmonid 
hatchery programs associated with the ESA-listed salmon and steelhead. 
Their evaluation was guided by NMFS' Policy on the Consideration of 
Hatchery-Origin Fish in Endangered Species Act Listing Determinations 
for Pacific Salmon and Steelhead (Hatchery Listing Policy) (70 FR 
37204; June 28, 2005). Under the Hatchery Listing Policy, we consider 
hatchery stocks to be part of an ESU/DPS if they exhibit a level of 
genetic divergence relative to the local natural population(s) that is 
no more than what occurs within the ESU (70 FR 37204; 37215). A 
memorandum (Jones 2015) summarizes their evaluation of the relatedness 
of hatchery stocks relative to the local natural populations to 
determine if the stocks warrant inclusion as part of the respective ESA 
listings (see the ``Delineation of Species'' section, below).
    Finally, we formed geographically-based teams of salmon management 
biologists from our West Coast Region to evaluate information related 
to the five ESA section 4(a)(1) factors. These teams produced ``5-Year 
Review Reports'' that incorporate the findings of the Northwest 
Fisheries Science Center's report, summarize new information concerning 
the delineation of the subject ESUs and DPSs and inclusion of closely 
related hatchery programs, and detail the evaluation of the ESA section 
4(a)(1) factors. An evaluation team conducted the review for the four 
ESA-listed salmon and steelhead species in the Snake River Basin and 
consolidated its evaluation and findings for these four species in a 
joint Snake River 5-Year Review Report (NMFS 2016).
    Separately, on November 2, 2015, we announced the availability of 
the proposed recovery plan for Snake River fall-run Chinook salmon 
(Proposed Recovery Plan) for public review and comment (80 FR 67386). 
On December 17, 2015, we announced a 30-day extension of the public 
comment period on the Proposed Recovery Plan (80 FR 78719). The 
Proposed Recovery Plan (NMFS 2015) includes an appendix (Appendix A) 
detailing a viability assessment for the Snake River fall-run Chinook 
ESU. Because the ESA section 4(b)(3)(B) status review for the Snake 
River fall-run Chinook ESU and the ESA section 4(c)(2)(A) 5-year 
reviews for all of the Snake River ESA-listed salmon and steelhead 
species were underway at the time the Proposed Recovery Plan was 
released, the viability assessment in Appendix A incorporated the 
available materials and analyses from the ongoing reviews. The results 
of the viability assessment detailed in Appendix A are incorporated in 
the Northwest Fisheries Science Center's report (NWFSC 2015). This 12-
month finding relies upon the information presented in the Proposed 
Recovery Plan's viability assessment (NMFS 2015, Appendix A), the 
Northwest Fisheries Science Center's report (NWFSC 2015), the review of 
West Coast salmonid hatchery programs (Jones 2015), the Snake River 5-
year Review Report (NMFS 2016), as well as pertinent information 
submitted as part of the public comment periods that was not otherwise 
incorporated in the aforementioned documents. These documents are 
available at our West Coast Region's Web site (see ADDRESSES, above).

Petition Finding

    Section 4(b)(3)(B) of the ESA requires us to make a finding within 
12-months of the date of receipt of any petition that was found to 
present substantial information indicating that the petitioned action 
may be warranted. The 12-month finding must provide a determination of 
whether the petitioned action is: (a) Not warranted; (b) warranted; or 
(c) warranted but precluded. In this case, we are responsible for 
determining whether the Snake River fall-run Chinook ESU warrants 
delisting from the ESA.
    The subject delisting petition asserts three points in support of 
the petitioned action: First, that NMFS may not base delisting criteria 
by considering only the status of natural (non-hatchery) fish; second, 
that the ESU has met NMFS' delisting criteria; and, third, that the ESU 
currently meets the statutory standards for delisting. We discuss these 
points in the pertinent sections below.

Determination of Species

    As currently listed, the Snake River fall-run Chinook salmon ESU 
consists of the one extant Lower Mainstem Snake River population, which 
includes all naturally spawned fall-run Chinook salmon originating from 
the mainstem Snake River below Hells Canyon Dam and from the Tucannon 
River, Grande Ronde River, Imnaha River, Salmon River, and Clearwater 
River subbasins. The ESU also includes four artificial propagation 
programs: The Lyons Ferry Hatchery Program, Fall Chinook Acclimation 
Ponds Program, Nez Perce Tribal Hatchery Program, and Oxbow Hatchery 
Program (70 FR 37200; June 28, 2005).
    Historically, the Snake River fall-run Chinook ESU also spawned 
above the Hells Canyon Dam Complex in the upper mainstem Snake River 
and tributaries (NWFSC 2015; NMFS 2015, Appendix A therein; NMFS 2016). 
This historical population is now extirpated. The area upstream of 
Hells Canyon historically supported the majority of all Snake River 
fall-run Chinook production until the area became inaccessible due to 
dam construction. The construction of Swan Falls Dam in 1901 blocked 
access to 157 miles including the historically productive fall-run 
Chinook habitat in the middle Snake River downstream of Shoshone Falls, 
a natural barrier to further upstream migration. The construction of 
dams associated with the Hells Canyon

[[Page 33472]]

Dam Complex in the late 1950s and 1960s barred the fish from the 
remaining spawning areas in the middle mainstem reach. The loss of this 
upstream habitat and inundation of downstream spawning areas by 
reservoirs associated with the Hells Canyon Complex and the lower Snake 
River dams reduced spawning habitat for the single extant population--
the Lower Mainstem Snake River population--to approximately 20 percent 
of the area historically available (NMFS 2016).
    As described above, the ESA's definition of `species' includes 
distinct population segments, which, for West Coast salmon includes 
ESUs. The petitioners did not request that we reconsider the 
composition of the listed Snake River fall-run Chinook ESU. 
Nonetheless, in our review, we solicited and evaluated all available 
information not previously considered that might inform a 
reconsideration of the reproductive isolation and evolutionary 
significance of the Snake River fall-run Chinook ESU. Information that 
can be useful in determining the degree of reproductive isolation 
includes incidences of straying, rates of recolonization, degree of 
genetic differentiation, and the existence of barriers to migration. 
Insight into evolutionary significance can be provided by data on 
genetic and life-history characteristics, habitat and ecological 
differences, and the effects of stock transfers or supplementation 
efforts on historical patterns of diversity. There was no such 
information that was not previously considered and that might warrant 
reconsideration of the geographical extent and composition of the Snake 
River fall-run Chinook ESU (NWFSC 2015).
    As part of our review, we also evaluated all hatchery programs 
geographically associated with the Snake River fall-run Chinook ESU to 
determine whether: Any of the four currently listed hatchery programs 
had been terminated; any new hatchery programs had been founded that 
would warrant inclusion in the ESU; the current level of divergence of 
any listed hatchery stocks relative to the local natural population had 
increased such that the stock(s) might warrant exclusion from the ESU; 
and, the level of divergence of any existing non-listed hatchery 
programs relative to the local natural population had decreased such 
that the stock(s) might warrant inclusion in the ESU. Our review of the 
hatchery programs associated with the Snake River fall-run Chinook ESU 
did not suggest that any changes in the ESU membership of hatchery 
programs are warranted (Jones 2015).
    Based on the foregoing information, we conclude that no changes in 
the definition of the Snake River fall-run Chinook ESU are warranted at 
this time. The Snake River fall-run Chinook ESU should remain defined 
as naturally spawned fall-run Chinook salmon originating from the 
mainstem Snake River below Hells Canyon Dam and from the Tucannon 
River, Grande Ronde River, Imnaha River, Salmon River, and Clearwater 
River subbasins. Also, fall-run Chinook salmon from four artificial 
propagation programs are included in the Snake River fall-run Chinook 
ESU: The Lyons Ferry Hatchery Program; Fall Chinook Acclimation Ponds 
Program; Nez Perce Tribal Hatchery Program; and the Tacoma Power 
(formerly ``Oxbow'') Hatchery Program.

Assessment of Extinction Risk

    We assess the extinction risk of Pacific salmon ESUs using the 
Viable Salmonid Population (VSP) concept developed by McElhany et al. 
(2000). The VSP concept evaluates four criteria--abundance, 
productivity, spatial structure, and diversity--to assess species 
viability. The risk of extinction of an ESU depends upon the abundance, 
productivity, geographic distribution, and diversity of the naturally 
spawned populations comprising it. Abundance and productivity need to 
be sufficient to provide for population-level persistence in the face 
of year-to-year variations in environmental conditions. Spatial 
structure of populations should provide for resilience to the potential 
impact of catastrophic events. Diversity should provide for patterns of 
phenotypic, genotypic, and life-history diversity that sustains natural 
production across a range of conditions, allowing for adaptation to 
changing environmental conditions.

Consideration of Hatchery-Origin Fish

    The petitioners assert that NMFS must consider the contribution of 
hatcheries in any delisting decision where hatchery fish are part of 
the ESU. The petitioners further state that it would be a violation of 
the ESA for NMFS to consider whether the Snake River fall-run Chinook 
ESU meets delisting criteria based only on whether natural, non-
hatchery spawners have met certain thresholds. We agree that hatchery 
fish must be included in our assessment of the Snake River fall-run 
Chinook ESU's status, in context of their contribution to conserving 
natural self-sustaining populations, as provided in our Hatchery 
Listing Policy.
    Pursuant to the Hatchery Listing Policy, we base our status 
determinations for Pacific salmon and steelhead on the status of the 
entire ESU, including any hatchery fish included in the ESU. As noted 
above, we consider a hatchery stock to be part of an ESU if the stock's 
level of genetic divergence relative to the local natural population(s) 
is no more than what occurs within the ESU (70 FR 37204; June 28, 
2005). Consistent with section 2(b) of the ESA (16 U.S.C. 1531(b)), we 
apply the Hatchery Listing Policy in support of the conservation of 
naturally-spawning salmon and the ecosystems upon which they depend (70 
FR 37204, 37215). Accordingly, we include hatchery fish in assessing 
the status of an ESU in the context of their contributions to 
conserving natural self-sustaining populations, which we evaluate by 
assessing the status of the natural fish that comprise the populations.
    The Hatchery Listing Policy recognizes that the presence of 
hatchery fish within an ESU can positively affect the overall status of 
the ESU, and thereby affect a listing determination, by contributing to 
the increased abundance and productivity of the natural populations in 
the ESU, improving spatial distribution, serving as a source population 
for repopulating unoccupied habitat, or conserving genetic resources of 
depressed natural populations in the ESU. Conversely, a hatchery 
program managed without adequate consideration of its adverse effects 
can affect the status of an ESU by reducing the reproductive fitness 
and productivity of the ESU, or reducing the adaptive genetic diversity 
of the ESU.
    There are four hatchery programs included in the Snake River fall-
run Chinook ESU: The Lyons Ferry Hatchery Program, Fall Chinook 
Acclimation Ponds Program, Nez Perce Tribal Hatchery Program, and Oxbow 
Hatchery Program. These hatchery programs release fish into the 
mainstem Snake River and Clearwater River which represent the majority 
of the remaining habitat available to this ESU. Our previous listing 
determination for the Snake River fall-run Chinook ESU concluded that 
these hatchery programs collectively do not substantially reduce the 
extinction risk of the ESU (70 FR 37160; June 28, 2005). These hatchery 
programs have contributed to the substantial increases in total ESU 
abundance and spawning escapement. However, the large fraction of 
naturally spawning hatchery fish complicates assessments of the ESU's 
productivity. The broad distribution of naturally spawning hatchery 
fish has increased

[[Page 33473]]

the ESU's spatial distribution, although the distribution of natural-
origin production in the extant population is unknown due to the 
prevalence of naturally spawning hatchery fish. The Lyons Ferry 
Hatchery program has preserved genetic diversity in the past during 
years of critically low abundance. However, the ESU-wide use of a 
single hatchery broodstock may pose long-term genetic risks, impede the 
expression of life-history diversity, and limit adaptation to different 
habitat areas.
    As explained above, we evaluate the status of Pacific Northwest 
salmon ESUs based on four biological criteria (abundance, productivity, 
spatial structure, and diversity) with respect to naturally-spawning 
fish, which reflects how hatchery fish are contributing to the 
viability of the ESU as a whole. We do not interpret the ESA as 
requiring that we assess extinction risk based on the abundance, 
productivity, spatial-structure, or diversity of hatchery fish. 
Furthermore, failing to account for the biological distinctions between 
hatchery and naturally spawned salmon would be inconsistent with our 
obligation to base ESA listing decisions on the best scientific and 
commercial data available. Our Hatchery Listing Policy has been upheld 
by the Federal courts as a reasonable interpretation of the ESA (Trout 
Unlimited v. Lohn, 599 F.3d 946 (9th Cir. 2009)). The court stated that 
``the ESA is primarily focused on natural populations,'' and that ``the 
[plaintiff's] demand for `equal treatment' of hatchery and naturally 
spawned fish during the [status] review process simply finds no 
grounding in the statutory text of the ESA'' (Id. at 957, 960). The 
petitioners' argument that we must treat hatchery and natural fish 
equally in evaluating the status of the ESU is inconsistent with our 
policy and with the court's decision.

Viability Criteria and Recovery Planning

    For the purposes of recovery planning and development of recovery 
criteria, in 2001 we convened the Interior Columbia Technical Recovery 
Team (Technical Recovery Team) composed of multi-disciplinary 
scientists from universities as well as Federal, state, and tribal 
agencies. The Technical Recovery Team was tasked with providing 
scientific support to recovery planners by developing biologically 
based viability criteria, analyzing alternative recovery strategies, 
and providing scientific review of draft plans. The Technical Recovery 
Team identified independent populations for each Snake River ESA-listed 
species. These independent populations were grouped into ``major 
population groups'' based on genetic similarities, shared habitat 
characteristics, population dispersal distances, and common life-
history traits. The Technical Recovery Team determined that the Snake 
River fall-run Chinook ESU was historically composed of a single major 
population group only. As noted above, the Snake River fall-run Chinook 
ESU has been determined to consist of the extant Lower Snake Mainstem 
population, and an extirpated population that historically occurred in 
the upper mainstem Snake River and tributaries above the present-day 
Hells Canyon Dam Complex (ICTRT 2003; NWFSC 2015; NMFS 2016).
    In 2007, the Technical Recovery Team also developed biological 
viability criteria, based on the VSP concept. The viability criteria 
reference the following levels of extinction risk: ``very low'' risk 
corresponds to less than a 1 percent risk of extinction over a 100-year 
period; ``low'' risk corresponds to a 1 to 5 percent risk of extinction 
over a 100-year period; ``moderate'' risk corresponds to a 6 to 25 
percent risk of extinction over a 100-year period; and ``high'' risk 
corresponds to a greater than 25 percent risk of extinction over a 100-
year period (ICTRT 2007). The Technical Recovery Team's report 
``Viability Criteria for Application to Interior Columbia Basin 
Salmonid ESUs'' describes the methodology and considerations for 
determining composite risk scores for abundance/productivity, and for 
spatial structure/diversity (ICTRT 2007). For an ESU to be determined 
viable, it needs to achieve at least an overall status of low risk 
through a combination of its abundance/productivity and spatial 
structure/diversity risks. An ESU is at least viable overall if its 
abundance/productivity risk is low to very low, and its spatial 
structure/diversity risk is moderate to very low.
    The Technical Recovery Team recognized that ESUs that contain only 
one major population group, such as the Snake River fall-run Chinook 
ESU, are inherently at greater risk of extinction due to more limited 
spatial structure and diversity, and potentially due to more limited 
abundance and productivity. To mitigate this inherently higher risk, 
the Technical Recovery Team applied more stringent viability criteria 
for ESUs with a single major population group. In addition to achieving 
an overall status of at least low risk (i.e., a 5 percent or less risk 
of extinction over 100 years), an ESU with a single major population 
group also needs to satisfy two additional conditions: Two-thirds or 
more of the historical populations within the ESU should meet the 
criteria for low risk; and at least two populations should meet the 
criteria for very low risk (i.e., highly viable). Applying the 
Technical Recovery Team's viability criteria, both a re-established 
population above the Hells Canyon Dam complex and the extant Lower 
Mainstem Snake River population would need to achieve highly viable 
status for the Snake River fall-run Chinook ESU to be considered for 
delisting. Highly viable status for these populations corresponds to 
very low risk in abundance/productivity and very low to low risk in 
spatial structure/diversity (the reader is referred to ICTRT (2007) for 
a detailed description of the Technical Recovery Team's viability 
criteria). The Technical Recovery Team recognized the difficulty of re-
establishing a fall-run Chinook population above the Hells Canyon Dam 
Complex, and suggested that initial recovery efforts emphasize 
improving the status of the extant population, while creating the 
potential for re-establishing an additional population (ICTRT 2007). 
The Technical Recovery Team also recognized that, in general, 
``different scenarios of ESU recovery may reflect alternative 
combinations of viable populations and specific policy choices 
regarding acceptable levels of risk'' (ICTRT 2007).
    During recovery planning for Snake River fall-run Chinook, we 
determined that the spatial complexity and size of the extant 
population provide opportunities for alternative viability scenarios as 
policy choices for delisting. Each scenario would require specific 
viability criteria and potential metrics for measuring viability 
characteristics designed to meet the basic set of viability objectives 
adopted by the Technical Recovery Team. Those alternative recovery 
scenarios are presented in the Proposed Recovery Plan (NMFS 2015) along 
with their corresponding alternative metrics for measuring viability. 
The scenarios provide a range of potential population characteristics 
that, if achieved, would indicate that the ESU has met the ESU-level 
recovery objectives. The scenarios are summarized briefly below:
    Scenario A--two populations, one highly viable and the other 
viable. This scenario would achieve ESU recovery by improving the 
status of the Lower Mainstem Snake River population to highly viable, 
and by reestablishing the extirpated Middle Snake River population 
above the Hells Canyon Dam Complex to viable status. While the 
Technical Recovery Team viability criteria would require both 
populations to meet highly viable status, this

[[Page 33474]]

scenario would only require ``viable'' status (low risk for abundance/
productivity, and moderate to very low risk for spatial structure/
diversity) for the reestablished Middle Snake River population. This 
scenario recognizes that a reestablished population above the Hells 
Canyon Dam Complex would provide the ESU protection against 
catastrophic losses, and that a highly viable Lower Mainstem Snake 
River population would provide a robust expression of life-history 
diversity.
    Scenario B--single population measured in the aggregate. Proposed 
scenario B illustrates a single-population pathway to ESU recovery, 
where VSP objectives would be evaluated in the aggregate (population-
wide), based on all natural-origin adult spawners. This single-
population recovery scenario recognizes the potential spatial 
complexity within the Lower Mainstem Snake River population, and the 
potential for the corresponding expression of life-history diversity in 
the population if it achieved highly viable status. This scenario would 
require that highly viable status for the extant population to be 
attained with a higher degree of statistical certainty than in proposed 
Scenario A.
    Potential additional scenarios--natural production emphasis areas. 
The Proposed Recovery Plan identifies the potential to develop 
additional single-population recovery scenarios that would be a 
variation on scenario B. Under these potential additional scenarios, 
``natural production emphasis areas'' for some major spawning areas 
would have a low percentage of hatchery-origin spawners and produce a 
significant level of natural-origin adult spawners. The remaining major 
spawning areas could have higher acceptable levels of hatchery-origin 
spawners than under Scenario B. The single population would still need 
to achieve a status of ``highly viable'' with a high degree of 
certainty.
    In lieu of a final Snake River fall-run Chinook recovery plan with 
final delisting scenarios against which to compare current ESU status, 
in this status review we must base our determination of whether 
delisting is warranted on the best scientific and commercial 
information available. The Technical Recovery Team viability criteria, 
and the proposed recovery scenarios articulated in the Proposed 
Recovery Plan, provide useful guides for evaluating the conditions that 
must be met for the petitioned delisting of Snake River fall-run 
Chinook to be warranted. All of the available viability criteria and 
recovery scenarios suggest that the extant Lower Mainstem Snake River 
population must be at least ``highly viable.'' While reestablishing the 
extirpated Middle Snake River population above the Hells Canyon Dam 
Complex may not be necessary to achieve recovery, the Lower Mainstem 
Snake River population must exhibit sufficient demographic and spatial 
complexity to reduce the risk of catastrophic loss, and must also 
exhibit sufficient diversity to ensure resilience against future 
environmental variability and change. If the extant Lower Mainstem 
Snake River population is highly viable, then it is possible that the 
Snake River fall-run Chinook ESU may warrant delisting. If the extant 
Lower Mainstem Snake River population is less than highly viable, it is 
unlikely that the ESU warrants delisting at this time.
    The petitioners argue that the Snake River fall-run Chinook ESU has 
met the viability criteria established by the Technical Recovery Team 
and should therefore be delisted. They assert that the long-term risk 
of ESU extinction is less than 1 percent within a 100-year period, and 
that the ESU has met NMFS' viability criteria. In particular, they 
argue that: The ESU has met abundance and productivity criteria; a 
second population of the ESU has been re-established in the Clearwater 
River, satisfying the spatial structure criterion; and NMFS' diversity 
criterion is ``antithetical to the ESA as currently applied to Pacific 
salmon.'' We address these contentions below.

Evaluation of Demographic Risks

    For a more detailed description of the analyses, updated status, 
trends and viability of the Snake River fall-run Chinook ESU, the 
reader is referred to the Northwest Fisheries Science Center report 
(NWFSC 2015) and the Updated Viability Assessment included in the 
Proposed Recovery Plan (NMFS 2015, Appendix A).

Abundance and Productivity

    The geometric-mean abundance for the most recent 10 years of annual 
spawner escapement estimates (2005-2014) is 6,418 natural-origin fish, 
with a standard error of 0.19. Natural-origin spawner abundance has 
increased relative to the levels reported in the last status review 
(Ford et al. 2011), driven largely by relatively high escapements in 
the most recent 3 years.
    In recent years, naturally spawning fall-run Chinook salmon in the 
lower Snake River have been comprised of both natural-origin returns 
originating from naturally spawning parents, as well as naturally 
spawning hatchery-origin fish. These hatchery-origin fall-run Chinook 
salmon escaping upstream of Lower Granite Dam to spawn naturally are 
considered to be part of the listed ESU, representing returns from a 
supplementation program that releases juvenile fish in reaches above 
Lower Granite Dam, as well as from releases at Lyons Ferry Hatchery 
that have dispersed upstream.
    Prior to the early 1980s, returns of Snake River fall-run Chinook 
salmon were likely predominately of natural-origin (NWFSC 2015). 
Natural return levels declined substantially following the completion 
of the Hells Canyon Dam Complex (1959-1967), and the construction of 
the lower Snake River dams (1962-1975). Based on extrapolations from 
sampling at Ice Harbor Dam (1977-1990), the Lyons Ferry Hatchery (1987-
present), and at Lower Granite Dam (1990-present), hatchery strays made 
up an increasing proportion of returns to the Lower Mainstem Snake 
River population through the 1980s. Strays from out-planting hatchery-
origin fall-run Chinook salmon from the Priest Rapids hatchery (an out-
of-ESU stock derived from the middle Columbia River fall-run Chinook 
stocks) and from the Lyons Ferry Hatchery program (considered part of 
the Snake River fall-run Chinook ESU) were the dominant contributors to 
these returns through the 1980s. Estimated natural-origin returns of 
Snake River fall-run Chinook salmon reached a low of less than 100 fish 
in 1990. Since the 1990s the proportion of natural-origin spawners in 
the Snake River fall-run Chinook ESU has continued to decline. From 
2010-2014, on average, 31 percent of spawners were of natural origin, 
compared to 37 percent (2005-2009), 38 percent (2000-2004), 58 percent 
(1995-1999), and 62 percent (1990-1994) in preceding years.
    The Northwest Fisheries Science Center report (NWFSC 2015) 
estimated the recruit per spawner productivity for the extant 
population (1990-2009 brood years) to be 1.53, with a standard error of 
0.18. The productivity analysis indicates that there have been years 
when abundance was high but productivity (recruits per spawner) fell 
below the replacement level, suggesting the potential influence of 
density-dependence, poor ocean conditions, or poor migration 
conditions. The report acknowledges that there is increasing 
statistical uncertainty surrounding the productivity estimate and it 
may not accurately reflect the true productivity of the current 
population. The true productivity of the extant population is masked by 
the recent high levels of naturally spawning hatchery fish. Survival 
improvements resulting from

[[Page 33475]]

improved flow conditions for spawning and rearing and increased passage 
survival through the hydropower system may have increased productivity 
in recent years. Conversely, recent productivity levels may have 
decreased as a result of negative impacts of chronically high hatchery 
proportions across all major spawning areas.
    The recent geometric-mean abundance of 6,418 natural spawners is 
higher than the Proposed Recovery Plan abundance criterion of 3,000 to 
4,200 natural spawners (for Scenario B--single population measured in 
the aggregate). The recent geometric-mean abundance is also higher than 
the Technical Recovery Team viability criteria of 3,000 natural 
spawners, though the Technical Recovery Team criteria contemplated two 
viable populations. Recent productivity has been relatively high 
(approximately 1.53), but it is lower than the Proposed Recovery Plan 
criterion of 1.7, which includes a buffer to reflect the uncertainty 
associated with recent productivity estimates. The recent productivity 
estimate is at or near the Technical Recovery Team productivity 
criterion of 1.5; however, the Technical Recovery Team criteria 
contemplated two highly viable populations. The current risk rating 
from the Northwest Fisheries Science Center report (NWFSC 2015) for 
abundance/productivity is low risk (i.e., between 1 and 5 percent 
probability of extinction over 100 years), and reflects uncertainty 
about whether recent increases in abundance (driven largely by 
relatively high escapements in the most recent 3 years) can be 
sustained over the long term. The Technical Recovery Team viability 
criteria, and all of the potential delisting scenarios in the Proposed 
Recovery Plan, would require that the extant population meet minimum 
requirements for ``highly viable'' status, which includes very low risk 
for abundance and productivity (ICTRT 2007; NMFS 2015; NMFS 2016). 
Recent abundance and productivity estimates (low risk) do not meet the 
Technical Recovery Team and proposed delisting scenarios criteria of 
very low risk (i.e., less than 1 percent probability of extinction over 
100 years) (NWFSC 2015; NMFS 2015, Appendix A). To achieve the 
necessary very low risk rating for abundance/productivity under a 
single-population recovery scenario, the extant population would need 
to demonstrate a 20-year geometric-mean productivity of 1.7 or greater 
(NMFS 2015). The extant population would need to exhibit increased 
productivity and/or a decrease in the year-to-year variability, while 
natural-origin abundance of the extant population would need to remain 
high (i.e., a recent 10-year geometric-mean abundance greater than 
4,200 natural-origin spawners). An increase in productivity could occur 
with a further reduction in mortalities across all life stages. Such an 
increase could be generated by actions such as a reduction in harvest 
impacts (particularly when natural-origin spawner return levels are 
low) and/or further improvements in juvenile survival during downstream 
migration (NWFSC 2015). Under a single-population recovery scenario 
with natural production emphasis areas, a very low risk rating for 
abundance/productivity could be achieved under current abundance levels 
if one or more major spawning aggregations exhibited relatively low 
levels of hatchery contributions to spawning (NMFS 2015). At present, 
there is no indication that any spawning areas are demonstrating lower 
proportions of hatchery-origin fish (NWFSC 2015).
    The petitioners assert that the recent abundance and productivity 
data demonstrate that the Snake River fall-run Chinook ESU has met the 
Technical Recovery Team viability criteria. As noted above, we agree 
that recent geometric-mean abundance and productivity estimates for 
Snake River fall-run Chinook meet or exceed the Technical Recovery Team 
abundance/productivity criteria; however, the Technical Recovery Team 
viability criteria contemplate a recovery scenario involving two highly 
viable populations (i.e., reestablishment of a viable Middle Snake 
River population above the Hells Canyon Dam Complex). The recent 
abundance and productivity estimates for the extant Lower Mainstem 
Snake River fall-run Chinook population fall short of the ``very low'' 
risk level that would be required under any of the proposed single-
population recovery scenarios.

Spatial Structure and Diversity

    The extant Lower Mainstem Snake River fall-run Chinook population 
consists of a spatially complex set of five historical major spawning 
areas (ICTRT 2007), each of which consists of a set of relatively 
discrete spawning patches of varying size (NMFS 2015). Although annual 
redd surveys show that Snake River fall-run Chinook spawning occurs in 
all five of the historical major spawning areas, the inability to 
obtain carcass samples representative of the mainstem major spawning 
areas makes assessment of natural-origin spawner distributions 
difficult. Reconstruction of natural-origin spawners based on hatchery 
expansions and data from homing/dispersal studies on acclimated 
hatchery releases indicate that four out of the five major spawning 
areas are contributing to naturally produced returns (NMFS 2015).
    The Northwest Fisheries Science Center report (NWFSC 2015) rated 
the spatial structure/diversity risk for the extant Snake River fall-
run Chinook population as moderate risk. The moderate risk rating 
reflects observed changes in major life-history patterns, shifts in 
phenotypic traits, and high levels of genetic homogeneity in samples 
from natural-origin returns. In particular, the moderate risk rating 
reflects the relatively high proportion of within-population hatchery 
spawners in all major spawning areas and the lingering effects of 
previous high levels of out-of-ESU strays. The potential for selective 
pressure imposed by current hydropower operations and cumulative 
harvest impacts also contribute to the moderate risk rating.
    For the extant Lower Mainstem Snake River population to achieve 
highly viable status with a high degree of certainty, the spatial 
structure/diversity rating needs to be at least low risk (NMFS 2015; 
ICTRT 2007). Achieving low risk for spatial structure/diversity for the 
Snake River fall-run Chinook ESU would either require re-establishing 
the extirpated population above Hells Canyon Dam, or that one or more 
major spawning areas in the Lower Mainstem Snake River population 
produce a significant level of natural-origin spawners with low 
influence from hatchery-origin spawners relative to the other major 
spawning areas. At present, given the widespread distribution of 
hatchery releases and hatchery-origin returns across all major spawning 
areas, and the lack of direct sampling of reach-specific spawner 
composition, there is no indication of a strong differential 
distribution of hatchery returns among major spawning areas.
    The petitioners assert that natural production from the Clearwater 
River should be regarded as a new population, and as such the 
petitioners contend that the Technical Recovery Team's (ICTRT 2007) 
spatial-structure viability criterion of two populations has been 
satisfied. We do not agree with the petitioners that the Clearwater 
River represents a separate fall-run Chinook spawning population. The 
Technical Recovery Team defined an independent population as being 
isolated to such an extent that exchanges of individuals among the 
populations do not substantially affect the population

[[Page 33476]]

dynamics or extinction risk of the independent populations over a 100-
year time frame (McElhany et al. 2000; ICTRT 2003). This basic 
definition from McElhany et al. (2000) was also adopted by technical 
recovery teams in other west coast salmon recovery domains. The 
Technical Recovery Team evaluated genetic information, distances 
between spawning areas related to dispersal (straying), as well as 
life-history and morphological characteristics as indicators of 
reproductive isolation among populations. The Clearwater River was 
identified by the Technical Recovery Team as one of the five major 
spawning areas within the Lower Mainstem Snake River population. The 
inclusion of fall-run Chinook in the Clearwater River as part of the 
Lower Mainstem Snake River population is supported by the close 
distance between spawning areas, the ecological similarity among the 
spawning areas, the aggressive supplementation efforts in the 
Clearwater River using a common broodstock collected at Lower Granite 
Dam, and the strong contribution of naturally spawning hatchery fish 
from this common hatchery broodstock in all spawning areas (ICTRT 
2003). The inclusion of natural production from the Clearwater River 
was considered as part of the spatial structure/diversity risk rating 
for the extant population. We also recognize that a high proportion of 
naturally produced fish originating from the Clearwater River are 
exhibiting yearling migration strategies due to the differing thermal 
regime in that major spawning area. The resulting contribution to 
overall phenotypic life-history diversity reduces the diversity risk to 
the ESU and was also considered in the spatial structure/diversity risk 
rating. However, this phenotypic life-history diversity, by itself, is 
not sufficient to warrant identifying fall-run Chinook in the 
Clearwater River as an independent population. There is no evidence of 
sufficient isolation between the fall-run Chinook in the Clearwater 
River and the other extant spawning areas in terms of discrete 
demographic patterns, differential straying/dispersal among the 
spawning areas, or genetic distinctiveness.
    The petitioners disagree with our approach to evaluating diversity 
risk, and assert that the increases in the total number of spawners 
denote low risk to diversity. We disagree with the petitioners' 
interpretation of diversity. A low risk to diversity requires 
demonstration of patterns of phenotypic, genetic and life-history 
traits that provide for resilience across a range of environmental 
conditions ensuring long-term evolutionary potential (NMFS 2015; ICTRT 
2007; McElhany et al. 2000). High levels of total spawner abundance 
alone do not indicate that essential diversity traits are being 
conserved.

Summary of Demographic Risks

    The Lower Mainstem Snake River fall-run Chinook salmon population 
is the only extant population remaining from an ESU that historically 
also included a population upstream of the current location of the 
Hells Canyon Dam Complex. The abundance of this remaining population 
has increased substantially in recent years, and the recent increases 
in natural-origin abundance are encouraging. Overall, the status of the 
Snake River fall-run Chinook ESU has improved compared to the time of 
listing and compared to prior status reviews. However, uncertainty 
remains regarding whether these abundance levels will be maintained, 
and improvements are needed in the species' productivity and diversity 
to achieve risk levels consistent with delisting (NWFSC 2015; NMFS 
2015; NMFS 2016).
    The overall current risk rating for the extant Lower Mainstem Snake 
River fall-run Chinook population is ``viable.'' This viable risk 
rating for the Lower Mainstem Snake River population is based on a low 
risk rating for abundance/productivity (i.e., 1 to 5 percent or less 
risk of extinction within 100 years), and a moderate risk rating for 
spatial structure/diversity (i.e., 6 to 25 percent of extinction within 
100 years) (NWFSC 2015; NMFS 2015, NMFS 2016). The Technical Recovery 
Team viability criteria, and all of the potential delisting scenarios 
in the Proposed Recovery Plan, would require that the extant population 
meet minimum requirements for ``highly viable'' status through a 
combination of very low risk for abundance and productivity, and low or 
very low risk for spatial structure and diversity (ICTRT 2007; NMFS 
2015; NMFS 2016). As such, the current biological viability of the 
Snake River fall-run Chinook ESU falls short of the demographic risk 
levels necessary to support delisting.

Summary of Factors Affecting the Species

    As described above, section 4(a)(1) of the ESA and NMFS 
implementing regulations (50 CFR part 424) state that we must determine 
whether a species is endangered or threatened because of any one or a 
combination of the following five factors: (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) inadequacy of 
existing regulatory mechanisms; or (E) other natural or man-made 
factors affecting its continued existence. We evaluated whether and the 
extent to which each of the foregoing factors contribute to the overall 
extinction risk of the Snake River fall-run Chinook ESU, and the 
findings are described in the 5-year Review Report (NMFS 2016). The 
section below summarizes our findings regarding the threats to the 
Snake River fall-run Chinook ESU. The petitioners' assertion that the 
ESU currently meets the statutory standards for delisting is addressed 
in the corresponding sections below.

(A) The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    Both hydropower and land-use activities have had significant 
impacts on habitat in the mainstem Snake River above Lower Granite Dam. 
Twelve dams have blocked and inundated habitat, impaired fish passage, 
altered flow and thermal regimes, and disrupted geomorphological 
processes in the mainstem Snake River. These impacts have resulted in 
the loss of historical habitat, altered migration timing, elevated 
dissolved gas levels, juvenile fish stranding and entrapment, and 
increased susceptibility to predation. In addition, land-use 
activities, including agriculture, grazing, resource extraction, and 
development, have adversely affected water quality and diminished 
habitat quality throughout the mainstem Snake River (NMFS 2016; NMFS 
2015).
    All spawning by Snake River fall-run Chinook is currently 
restricted to the area downstream of the Hells Canyon Dam Complex, 
where historically only limited spawning occurred (NMFS 2016; NMFS 
2015). A large portion of the historical upriver habitat was lost 
following construction of Swan Falls Dam on the Snake River in 1901, 
but construction of the Hells Canyon Complex of dams in the late 1950s 
and 1960s blocked access to remaining upriver spawning areas, and 
resulted in the extirpation of one of two populations that historically 
constituted this ESU. The blocked habitat areas above the Hells Canyon 
Dam Complex historically were the most productive for Snake River fall-
run Chinook.
    Although successful reintroduction of fall-run Chinook salmon above 
the Hells Canyon Dam Complex would contribute to the recovery of the 
ESU, the mainstem habitat above the complex is currently too degraded 
to support

[[Page 33477]]

anadromous fish. Agriculture, grazing, mining, timber harvest, and 
development activities have led to excessive nutrients, sedimentation, 
toxic pollutants, low dissolved oxygen, altered flows, and severely 
degraded water quality in the upper mainstem Snake River (NMFS 2016; 
NMFS 2015).
    Below the Hells Canyon Dam Complex, one extant population in the 
ESU consists of a spatially complex set of five historical major 
spawning areas: Two reaches of the mainstem Snake River, and the lower 
mainstem reaches of the Grande Ronde River, the Clearwater River, and 
the Tucannon River. Habitat concerns in the fall-run Chinook spawning 
areas of the Clearwater River include elevated temperature, sediment, 
and nutrients, flow management, and toxic pollutants. The lower 
Clearwater River is highly influenced by operations at Dworshak Dam. 
Since 1992, cold water releases at Dworshak Dam have been managed to 
improve migration conditions (temperature and flow) in the lower Snake 
River (NMFS 2016; NMFS 2015). In the Lower Grande Ronde River mainstem, 
limiting factors include the lack of habitat quality and diversity, 
excess fine sediment, degraded riparian conditions, low summer flows, 
and poor water quality. The Tucannon River is limited primarily by 
sediment load and habitat quantity, with sediment impacts on fall-run 
Chinook egg incubation and fry colonization considered moderate to high 
in most reaches, primarily due to agricultural land uses (NMFS 2016; 
NMFS 2015).
    Flow management of the Columbia River hydropower system affects 
fish density in the estuary and ocean, fish size and condition, the 
timing of ocean entry, and the growth and survival of fish during later 
fish life stages. In the estuary, flow management, diking and filling 
have reduced the availability of in-channel and off-channel habitat for 
extended rearing of subyearling juvenile Chinook, including components 
of the Snake River fall-run Chinook ESU. The impact of the loss of 
estuary habitat complexity likely differs between the fall-run Chinook 
subyearling and yearling life history-types. The yearlings often 
migrate through the estuary within about a week, while sub-yearlings 
can linger for up to several months in shallow nearshore estuary 
habitat areas (NMFS 2016; NMFS 2015).
    The petitioners assert that there is no continued destruction, 
modification, or curtailment of the habitat or range of the Snake River 
fall-run Chinook ESU that justifies maintaining the species' ESA 
listing as threatened. The petitioners argue that the habitat changes 
are ultimately reflected in population status and trends, and that the 
recent high levels of abundance demonstrate that the effects of any 
historical habitat loss or degradation no longer constrain the 
population. However, as noted above, the historical loss of habitat due 
to the establishment of mainstem hydropower dams continues to represent 
a threat to the spatial structure and diversity of the ESU. Ongoing 
habitat concerns, described above, due to land-use practices and flow 
management result in degraded water and habitat quality in the area 
above the Hells Canyon Dam Complex, the spawning area in the lower 
Clearwater River, and in the other spawning areas of the Lower Mainstem 
Snake River population (NMFS 2016; NMFS 2015). Additionally, flow 
management and the loss of Columbia River estuarine habitat have 
reduced the availability of rearing habitat for migrating juvenile 
Snake River fall-run Chinook (NMFS 2016; NMFS 2015). As such, we 
disagree with the petitioners' assertion that historical habitat loss 
and degradation no longer constrain the population, and furthermore, we 
find that the continued degradation of habitat poses a threat to the 
Snake River fall-run Chinook ESU.
    If the recovery of the Snake River fall-run Chinook ESU is to 
include reestablishment of a spawning population above the Hells Canyon 
Dam Complex, the mainstem habitat above the complex is currently too 
degraded to support anadromous fish. With respect to the extant Lower 
Mainstem Snake River population, there is considerable uncertainty as 
to whether current habitat conditions are sufficient for the population 
to improve to, and be sustained at, a highly viable level. The 
Northwest Fisheries Science Center's productivity analysis (NWFSC 2015) 
suggests the potential influence of density dependence, poor ocean 
conditions, or poor migration conditions. The lack of major spawning 
aggregations with low levels of hatchery influence makes it difficult 
to evaluate the sufficiency of lower mainstem habitat conditions. It is 
unclear if current habitat conditions can sustain the recent high 
levels of adult returns and provide resiliency during periods of poor 
marine or freshwater survival.
    Habitat conditions have improved since the last status review (Ford 
et al. 2011); however, habitat concerns remain throughout the Snake 
River Basin, particularly in regards to mainstem and tributary stream 
flows, floodplain management, and elevated water temperatures. We 
conclude that historical habitat loss, and continued degradation and 
modification of habitat below the Hells Canyon Dam Complex, continue to 
pose a risk to, and limit the recovery of, the Snake River fall-run 
Chinook ESU. However, the Snake River 5-year Review Report (NMFS 2016) 
and the Proposed Recovery Plan (NMFS 2015) outline several 
opportunities for habitat improvements to provide meaningful 
improvements in ESU viability.

(B) Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Snake River fall-run Chinook are incidentally caught by both ocean 
and in-river fisheries, and harvest in these fisheries has the 
potential to produce selective pressure on migration timing, maturation 
timing, and size-at-age. No direct estimates are available of the 
degree of selective pressure caused by ocean harvest impacts on 
natural-origin Snake River fall-run Chinook. However, ocean 
exploitation rates based on coded wire tag (CWT) results for sub-
yearling releases of Lyons Ferry Hatchery fish are used as surrogates 
in fisheries management modeling (NMFS 2015, Appendix A). Average 
annual ocean exploitation rates vary by age, increasing from relatively 
low levels on age-2 fish to approximately 25 percent on age-4 and age-5 
fish (NMFS 2015, Appendix A). Based on the current timing and 
distribution of the fisheries with CWT recoveries, ocean harvest of 
Snake River fall-run Chinook salmon is assumed to impact both maturing 
and immature fish (NMFS 2015, Appendix A). As a result, the cumulative 
impact of ocean harvest is higher on components of the run maturing at 
older ages. Snake River fall-run Chinook salmon are also harvested by 
in-river fisheries, largely in mainstem Columbia River fisheries on 
aggregate fall-run Chinook salmon runs, including the highly productive 
Hanford Reach stock. Exploitation rates of in-river fisheries also 
increase with age-at-return.
    Fishery impacts from ocean and in-river fisheries on Snake River 
fall-run Chinook viability are controlled through harvest agreements 
(e.g., the Pacific Salmon Treaty, May 2008 U.S. v. OR Management 
Agreement). These agreements, on average, have reduced impacts of 
fisheries on Snake River fall-run Chinook. Year-specific acceptable 
harvest rates are determined by an abundance-based framework that 
constrains the aggregate of ocean and in-river fisheries in years of 
low abundance, and allows for increased harvest opportunity in years of 
high abundance. Information available since the 2011 status review 
indicates that combined ocean and in-river harvest

[[Page 33478]]

rates have remained at approximately 33 percent annually for Snake 
River fall-run Chinook (NMFS 2016).
    Snake River fall-run Chinook are also taken through scientific 
research activities. Robust and multifaceted research and monitoring 
efforts are underway in the Snake River Basin to inform analyses of 
habitat status and trends, fish population status and trends, 
population response to various habitat conditions and restoration 
treatment types, and the effectiveness of various types of actions in 
addressing specific limiting factors for all of the listed Snake River 
salmonid species. Given the mounting demand for take under various 
research and monitoring initiatives, it is likely that these activities 
are having an increasing negative impact on the Snake River species, 
including Snake River fall-run Chinook. However, these research and 
monitoring efforts are closely scrutinized through ESA section 
10(a)(1)(A) and 4(d) research-permit approvals to ensure that such 
activities do not operate to the disadvantage of the species. The total 
mortality authorized for all scientific research permits on natural-
origin adult Snake River fall-run Chinook is approximately 0.01 percent 
of the recent 10-year geometric-mean abundance.
    The petitioners argue that there is no evidence to conclude that 
overutilization is, or has been, a threat to the ESU. We conclude that 
the risk to the persistence of the ESU due to overutilization remains 
essentially unchanged since the last status review (Ford et al. 2011), 
and does not pose a threat to, nor limit the recovery potential of, the 
Snake River fall-run Chinook ESU. Accordingly, we do not address 
petitioners' arguments regarding this factor.

(C) Disease or Predation

    Predation, competition, other ecological interactions, and disease 
affect the viability of Snake River fall-run Chinook salmon by reducing 
abundance, productivity, and diversity. Predation rates by both fish 
and birds on subyearling Snake River fall-run Chinook are a concern 
during the smolt outmigration. Northern pikeminnow, smallmouth bass and 
avian predators selectively target subyearling outmigrants relative to 
larger yearling migrants. Consequently, mortality due to this predation 
influences species diversity, as well as abundance and productivity. 
Predation by sea lions and other marine mammals has less of an effect 
on species viability because most adult Snake River fall-run Chinook 
are not migrating through the lower Columbia River in the spring when 
the marine mammals are most abundant.
    Currently, it is not clear whether or how density-dependent habitat 
effects, and competition with hatchery-origin fish for limited habitat, 
are influencing natural-origin production. It is also unclear whether 
competition between adult Snake River fall-run Chinook salmon and non-
native species, such as shad, in the mainstem migration corridor and 
estuary is affecting species viability. Additional research is needed 
to understand the potential significance of this risk.
    Disease rates over the past 5 years are believed to be consistent 
with the previous review period. Climate change impacts such as 
increasing temperature may increase susceptibility to diseases. The 
disease rates have continued to fluctuate within the range observed in 
past review periods and are not expected to affect the extinction risk 
of the Snake River fall-run Chinook ESU.
    We conclude that the current levels of disease, predation, 
competition and other ecological interactions are not a threat to the 
persistence or recovery potential of the Snake River fall-run Chinook 
ESU (NMFS 2016). Because we conclude that this factor is not currently 
limiting species recovery, we do not address the petitioners' arguments 
regarding this factor.

(D) Inadequacy of Existing Regulatory Mechanisms

    Various Federal, state, county and tribal regulatory mechanisms are 
in place to reduce habitat loss and degradation caused by human land-
use and development, as well as reduce risks due to the hydropower 
system, harvest and hatchery impacts, and predation. New information 
available since the last status review (Ford et al. 2011) indicates 
that the adequacy of some regulatory mechanisms has improved. 
Noteworthy improvements in specific regulatory mechanisms are 
summarized in the Snake River 5-year review report (NMFS 2016).
    There are a number of remaining concerns regarding existing 
regulatory mechanisms, including:
     Lack of documentation or analysis of the effectiveness of 
land-use regulatory mechanisms and land-use management programs.
     Revised land-use regulations to allow development on rural 
lands (Adoption of Measure 37, with modification by Measure 49, in 
Oregon).
     Water rights allocation and administration issues in 
Oregon and Idaho.
     Continued implementation of management actions in some 
areas, which negatively impacts riparian areas.
     Lack of implementation and documented impacts or 
improvements of completed Total Maximum Daily Load standards (TMDLs) in 
Oregon.
     Increased mining and mineral extraction activities. In 
Idaho, mining still takes place under the 1872 Mining Law, giving 
agencies limited discretion in how they regulate it. Issues related to 
mining threats in the Snake River Basin have expanded since the last 
status review.
     Effects of commonly applied chemical insecticides, 
herbicides, and fungicides which are authorized for use per the 
Environmental Protection Agency label criteria. All West Coast 
salmonids are identified in a series of NMFS section 7 consultations as 
jeopardized by at least one of the analyzed chemicals; most are 
identified as being jeopardized by many of the chemicals. In 2014, a 
jeopardy biological opinion was issued for Idaho and, in 2012, for 
Oregon, regarding the respective state's water quality standards for 
toxic pollutants (NMFS 2016). This will result in promulgation of new 
standards for mercury, selenium, arsenic, copper and cyanide in Idaho; 
and for cadmium, copper, ammonia, and aluminum in Oregon.
     Development within floodplains, which continues to be a 
regional concern. This frequently results in stream bank alteration, 
stream bank armoring, and stream channel alteration projects to protect 
private property that do not allow streams to function properly and 
result in degraded habitat. It is important to note that, where it has 
been analyzed, floodplain development that occurs consistently with the 
National Flood Insurance Program's minimum criteria has been found to 
jeopardize 18 species of West Coast salmonids.
     The need for future Forest Service Plan reviews to 
continue to address how forest practices can support recovery of salmon 
and steelhead.
    The risk to the species' persistence because of the inadequacy of 
existing regulatory mechanisms has decreased slightly, based on the 
improvements noted in the Snake River 5-year review report (NMFS 2016). 
The petitioners assert that the increases in abundance for Snake River 
fall-run Chinook demonstrate that inadequacy of regulatory mechanisms 
cannot be a threat to Snake River fall-run Chinook. We do not agree 
with the petitioners' argument that we should evaluate this statutory 
factor based solely on the abundance of the ESU. As noted above,

[[Page 33479]]

we identified historical habitat loss and continued habitat degradation 
and modification below the Hells Canyon Dam Complex as ongoing threats 
to the Snake River fall-fun Chinook ESU. These ongoing threats could be 
ameliorated by strengthening existing regulatory mechanisms (NMFS 
2016). As such, we conclude that the inadequacy of existing regulatory 
mechanisms continues to pose a threat to the persistence and limit the 
recovery potential of the Snake River fall-run Chinook ESU.

(E) Other Natural or Man-Made Factors Affecting Its Continued Existence

    The petitioners note that our final rule listing the Snake River 
fall-run Chinook ESU identified drought as a factor that may have 
contributed to reduced productivity, and argue that drought is no 
longer a factor affecting the species due to flow regulation by the 
Federal Columbia River Power System. Our current status review (NMFS 
2016) for the species does not identify drought as a factor affecting 
the species' continued existence. However, we have identified other 
factors in this category that present a risk to the species' future 
persistence.

Climate Change

    The potential impacts of climate change on the extinction risk and 
recovery potential of the Snake River fall-run Chinook ESU are 
described in more detail in the Proposed Recovery Plan (NMFS 2015). 
Climate experts predict physical changes to rivers and streams in the 
Columbia Basin that include: Warmer atmospheric temperatures resulting 
in more precipitation falling as rain rather than snow; diminished snow 
pack resulting in altered stream flow volume and timing; increased 
winter flooding; lower late summer flows; and a continued rise in 
stream temperatures. These changes in air temperatures, river 
temperatures, and river flows are expected to cause changes in salmon 
and steelhead distribution, behavior, growth, and survival, in general. 
However, the magnitude and timing of these changes, and specific 
effects on Snake River fall-run Chinook salmon remain unclear.
    Climate change and increased water temperatures in the mainstem 
lower Snake River could cause delays in adult migration and spawn 
timing, increased adult mortality, and reduced spawning success. Delays 
in adult migration and spawn timing in turn could cause delays in fry 
emergence and dispersal and delayed smolt outmigration, although it is 
also possible that increased overwintering temperature could reduce the 
impacts on emergence timing. If delays in emergence timing are long 
(e.g., weeks) then the timing of smolt outmigration may be altered. 
This could result in a marine transition potentially poorly timed with 
favorable ocean conditions, and possibly increase exposure to 
predators. Warmer temperatures will increase metabolism, which may 
increase or decrease juvenile growth rates and survival, depending upon 
availability of food. Increases in water temperatures in Snake and 
Columbia River reservoirs could also increase predation on juveniles by 
warm-water fish species, and increase food competition with other 
species such as shad. Reduced flows in late spring and summer may lead 
to delayed outmigration of juveniles and higher mortality.
    The effects of climate change on Snake River fall-run Chinook in 
the estuary and plume may include a reduction in the quantity and 
quality of rearing habitat, and an altered distribution of salmonid 
prey and predators. The effects of climate change in marine 
environments include increased ocean temperature, increased 
stratification of the water column, changes in the intensity and timing 
of coastal upwelling, and ocean acidification. Modeling studies that 
explore the marine ecological impacts of climate change have concluded 
that salmon abundances in the Pacific Northwest and Alaska are likely 
to be reduced. Uncertainty regarding the long-term impacts of climate 
change and the ability of Snake River fall-run Chinook to successfully 
adapt to an evolving ecosystem represent risks to the species' 
persistence and recovery potential.

Hatchery Fish

    Snake River fall-run Chinook salmon hatchery production has 
increased and so have hatchery-origin returns. Considerable uncertainty 
remains about the effect of the Snake River fall-run Chinook hatchery 
programs on the Lower Mainstem Snake River population. Much of this 
uncertainty reflects the fact that the remaining population is very 
difficult to study because of its geographic extent, habitat, and 
logistical issues. This uncertainty, however, is more important in the 
case of Snake River fall-run Chinook than in many other ESA-listed 
salmonid populations because the current population is the only extant 
population in the ESU, and it must reach a highly viable level under 
any scenario for the ESU to be considered recovered (ICTRT 2007; NMFS 
2015). As noted above in the Evaluation of Demographic Risks, the true 
productivity of the extant population is masked by the recent high 
levels of naturally spawning hatchery fish, and this high proportion of 
within-population hatchery spawners in all major spawning areas 
contributes to the moderate risk rating in spatial structure and 
diversity.
    We conclude that, based on the high level of uncertainty associated 
with projecting the impacts of climate change and resolving the 
influence of hatchery production, other natural or man-made factors 
represent a threat to the persistence and recovery potential of the 
Snake River fall-run Chinook.

Efforts Being Made To Protect the Species

    Section 4(b)(1)(A) of the ESA requires the Secretary to make 
listing determinations solely on the basis of the best scientific and 
commercial data available after taking into account efforts being made 
to protect a species. Therefore, in making listing determinations, we 
first assess ESU extinction risk and identify factors that have led to 
its decline. Then we assess existing efforts being made to protect the 
species to determine if those measures ameliorate the threats or 
section 4(a)(1) factors affecting the ESU.

Summary of Protective Efforts

    Previous listing determinations have described ongoing protective 
efforts that are likely to promote the conservation of ESA-listed 
salmonids, including the Snake River fall-run Chinook. In the Snake 
River Basin 5-year Review Report (NMFS 2016), we note the many habitat, 
hydropower, hatchery, and harvest improvements that occurred in the 
past 5 years. We are currently working with our Federal, state, and 
tribal co-managers to develop monitoring programs, databases, and 
analytical tools to assist us in tracking, monitoring, and assessing 
the effectiveness of these improvements.
    The abundance of natural-origin Snake River fall-run Chinook in the 
one extant population has increased substantially since listing. We 
attribute this increase to a combination of actions that improved 
survivals through the hydropower system, reduced harvest, and increased 
production through hatchery supplementation. Key protective actions 
related to Snake River fall-run Chinook mainstem and tributary habitat 
include (NMFS 2015; NMFS 2016):
     Continued implementation of Idaho Power Company's fall 
Chinook salmon spawning program to enhance and maintain suitable 
spawning and incubation conditions.

[[Page 33480]]

     Continued implementation of the FCRPS Biological Opinion, 
including hydropower system operations such as cool-water releases from 
Dworshak Dam to maintain adequate migration and rearing conditions in 
the lower Snake River, summer flow augmentation and summer spill at 
multiple projects to maintain migration and passage conditions, and 
operations at Lower Granite Dam to address adult passage blockages 
caused by warm surface waters entering the fish ladders.
     Continued implementation of Lower Snake River Programmatic 
Sediment Management Plan measures to reduce impacts of reservoir and 
river channel dredging and disposal on Snake River fall-run Chinook.
     Continued implementation of recovery plan actions in 
tributary and lower mainstem habitats to maintain and improve spawning 
and rearing potential for Snake River fall-run Chinook (Although these 
actions are generally focused on Snake River spring/summer Chinook 
salmon and steelhead and, therefore, located above fall-run Chinook 
spawning and rearing habitats, the actions have cumulative beneficial 
effects on downstream habitats).
     Large-scale restoration projects in the Tucannon River, 
which have been highly effective in reestablishing channel functions 
related to temperature, floodplain connectivity, channel morphology, 
and habitat complexity. These key protective efforts were largely 
possible thanks to the persistence and support from the Snake River 
Salmon Recovery Board, Washington Department of Fish and Wildlife, and 
local restoration partners.
    Programs such as these are critical if we are to address the 
threats and limiting factors facing the ESU to improve its viability. 
However, at this time, we conclude that these and other protective 
efforts are insufficient to ameliorate the threats facing the Snake 
River fall-run Chinook ESU to the extent where delisting would be 
warranted.

Final Determination

    The petitioners' arguments that the Snake River fall-run Chinook 
ESU should be delisted are based in large measure upon the prevalence 
of hatchery-produced fish and their view that we impermissibly 
emphasize the naturally spawned component of the ESU in our viability 
assessments. We disagree and conclude that, consistent with the 
Hatchery Listing Policy and the Ninth Circuit Court of Appeals ruling 
in Trout Unlimited v. Lohn, hatchery fish should be evaluated in the 
context of their contributions to the conservation of the naturally 
spawned population(s).
    As noted above (see Viability Criteria and Recovery Planning), the 
Technical Recovery Team viability criteria (ICTRT 2007) and the 
proposed recovery scenarios articulated in the Proposed Recovery Plan 
(NMFS 2015) provide useful guides for evaluating the conditions that 
must be met for the delisting of Snake River fall-run Chinook to be 
warranted. All the viability criteria and proposed recovery scenarios 
conclude that the extant Lower Mainstem Snake River population must be 
at least highly viable. The Northwest Fisheries Science Center report 
(NWFSC 2015) concluded that the Lower Mainstem Snake River population 
is currently viable, but is less than highly viable. In other words, 
the current risk level of the Snake River fall-run Chinook ESU does not 
meet the status described in the Technical Recovery Team report and the 
Proposed Recovery Plan as necessary for the recovery of the ESU.
    Additionally, based on our evaluation of the five section 4(a)(1) 
factors, above, we conclude that historical habitat loss, continued 
degradation and modification of habitat, and the inadequacy of 
regulatory mechanisms continue to pose threats to, and limit the 
recovery potential of, the Snake River fall-run Chinook ESU. Disease, 
predation, and overutilization do not pose threats to the ESU at this 
time. We also find that the high levels of uncertainty associated with 
projecting the effects of other natural or man-made factors affecting 
the continued existence of the ESU represent a threat to the 
persistence and recovery potential of the Snake River fall-run Chinook 
ESU. This latter uncertainty, particularly that conferred by the 
prevalence and broad distribution of hatchery-origin fish across all 
major spawning areas, needs to be addressed if we are to be able to 
assess the viability of the extant Lower Mainstem Snake River 
population with sufficient certainty. After reviewing efforts being 
made to protect salmonids and their habitat in the Snake River Basin, 
we conclude that these efforts are insufficient to ameliorate the 
threats facing the Snake River fall-run Chinook ESU to the point where 
the species would warrant delisting.
    Based on our review of the species' viability, the five section 
4(a)(1) factors, and efforts being made to protect the species, we 
conclude that the Snake River fall-run Chinook ESU is likely to become 
an endangered species throughout all or a significant portion of its 
range in the foreseeable future. We conclude that the petitioned action 
to delist the Snake River fall-run Chinook ESU is not warranted at this 
time, and as such it shall retain its status as a threatened species 
under the ESA.

References

    A complete list of all references cited herein is available upon 
request (see FOR FURTHER INFORMATION CONTACT).

Authority

    The Authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: May 19, 2016.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. 2016-12453 Filed 5-25-16; 8:45 am]
 BILLING CODE 3510-22-P