Southern Resident Killer Whales (Orcinus orca) 5-Year Review : Summary and Evaluation
The Southern Resident killer whale Distinct Population Segment (DPS) was listed as endangered under the Endangered Species Act (ESA) in 2005. In the listing, the National Marine Fisheries Service (NMFS) identified three main threats to their survival: 1) scarcity of prey, 2) high levels of contaminants from pollution, and 3) disturbance from vessels and sound. As of 1 July 2016 after the summer census, there were only 83 individuals left in the population (CWR 2016). Their small population size and social structure also puts them at risk for a catastrophic event, such as an oil spill, that could impact the entire population. Updates regarding research and management actions for the primary threats (prey, pollution and vessels) are included below and in discussions of whether the recovery criteria related to each of the threats have been met. This review fulfills our requirement under section 4(c)(2) of the ESA to conduct, at least once every five years, a review of listed species to ensure that the listing of these species remains accurate.