NOAA Fisheries 10-year study highlights threats to Southern Resident killer whales

June 25, 2014

The killer whales' distinctive appearance consists of black dorsal (back) and white ventral (belly) portions, with a white patch above and behind the eye and a gray patch behind the dorsal fin. (Credit: NOAA).

The killer whales' distinctive appearance consists of black dorsal (back) and white ventral (belly) portions, with a white patch above and behind the eye and a gray patch behind the dorsal fin. (Credit: NOAA)

A NOAA report released today, which focuses on 10 years of research and conservation efforts on the endangered Southern Resident killer whales, confirms that the three major threats to the recovery of the animals are pollution, vessel noise, and food availability.  

Since 2003, NOAA scientists have collected data ranging from fecal and biopsy samples to satellite location data and behavioral observations in order to provide a comprehensive look into the health of this population and inform recovery efforts.

With only 80 of the animals left, recovery of the Southern Resident killer whale population, which spends summers in Puget Sound, is going to require years of study and work, according to NOAA Fisheries marine biologist Lynne Barre.

Killer whales pods contain several matrilineal sub-groups (mothers with offspring) that travel together as a single family unit. (Credit: NOAA).

Killer whales pods contain several matrilineal sub-groups (mothers with offspring) that travel together as a single family unit. (Credit: NOAA)

“This new report provides insights into the threats facing Southern Resident killer whales, as well as new information as to why these whales are not recovering as quickly as hoped,” Barre said. “NOAA Fisheries and our partners can use the findings and information contained in this report, as well as future research, and apply it directly to our overall efforts to help these animals recover as we work to maintain healthy oceans for current and future generations.”

According to the report, NOAA is tackling the main threats to the whales on a number of fronts, by implementing restrictions on how close vessels can approach the whales in order to reduce impacts; collaborating and partnering with organizations responsible for the removal of contaminants in Puget Sound; better understanding effects of food availability; and adopting killer whale-specific plans in the case of oil spills.

Today’s report also summarizes what NOAA Fisheries and its partners have learned, conservation actions taken, and future actions that need to be taken:

In 2003, Congressional concern over the 20 percent population decline in the late 1990s led to a federally funded research and conservation program. Since that time, NOAA Fisheries has been working with the killer whale conservation community to more fully understand the threats these whales face, and to initiate actions to help the species recover.

It is believed the Southern Resident killer whale population once numbered at least 140 animals. In the 1960s and 1970s, nearly 50 animals were removed from the population and placed into theme parks. The practice of capturing live orcas for display was halted in 1976, but only about 71 Southern Residents remained.

The population of these whales rebounded in the 1980s, peaking at 98 animals in 1995. But the population began to decline again in the early 2000s, and was listed as endangered under the Endangered Species Act in 2005. In 2013, the population numbered 82 animals.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on FacebookTwitter, Instagram and our other social media channels.