On January 5, 2017, the National Marine Fisheries Service (NMFS) published notice of the availability of the final Recovery Plan for the Cook Inlet Beluga Whale (Delphinapterus leucas). The Endangered Species Act (ESA) requires the preparation and implementation of recovery plans for all listed species, unless the Secretary of Commerce determines that doing so does not promote the recovery of the species. NMFS listed the Cook Inlet distinct population segment (DPS) of beluga whale (CI beluga) as endangered under the ESA in 2008 and designated critical habitat in 2011.
Photo: NOAA Fisheries
Approximately 340 CI beluga remained in 2014, down from a high of nearly 1300 in 1979. The Cook Inlet is a semi-enclosed tidal estuary in southcentral Alaska; CI beluga are the most reproductively and demographically isolated of all the Alaskan beluga whales. As such, CI beluga are highly susceptible to stochastic events.
The Recovery Plan acknowledges that the reasons for the CI beluga’s decline are not well understood. In order to focus efforts and resources on actions that are more likely to benefit CI beluga recovery, the Recovery Plan identifies ten potential threat types and rates their overall relative concern to CI beluga. The Plan focuses recovery efforts on threats identified as of medium or high relative concern including catastrophic events (e.g., natural disasters; spills; mass strandings), cumulative effects of multiple stressors, noise, disease agents (e.g., pathogens, parasites, and harmful algal blooms), habitat loss or degradation, reduction in prey, and unauthorized take. Threats of low relative concern that will be reassessed from time to time include pollution, predation, and subsistence hunting.
The Recovery Plan specifies a minimum population size of 520 individuals to downlist CI beluga from endangered to threatened and 840 individuals to delist. Recommended recovery actions include research, monitoring, education/outreach efforts, and threat management, such as evaluating the effect of prey abundance on the DPS’s fitness.
