The Orca Connection
The Southern Resident Orca Whales of Washington State's Puget Sound are a critical part of the Northwest ecosystem and economy, drawing millions of tourism dollars each year. They are also endangered, facing severe threats to their survival. One of the major problems orca's face is a lack of food, and that means salmon. Read more for additional information on how these two critical Northwest species are connected.
New study: Puget Sound's orcas concentrate at the Columbia River's mouth during Spring
From the desk of Joseph Bogaard
February 2, 2014
A recently-published study from the Journal of the Acoustical Society of America makes new findings that connect endangered Southern Resident Killer Whales (SRKWs) with threatened and endangered salmon of the Columbia and Snake Rivers. NOAA-Fisheries, the federal agency charged with protecting has previously identified the historic predation by these orcas on Columbia Basin chinook salmon and have previously described the decline of salmon in the Columbia River basin as “[p]erhaps the single greatest change in food availability for resident killer whales since the late 1800s...”
Today, there is strong evidence that the SRKWs are often suffering from severe nutritional stress (starving). The lack of available prey has been documented as a key source of mortality and low reproductive success in recent years. This new study confirms the recent presence of SRKWs at or near the mouth of the Columbia River in March/April and speculates that they are drawn there to feed on oily, energy-rich spring chinook that also gather at the river’s mouth in March before beginning their upriver migration.
Needless to say, a Columbia Basin that produces many more chinook salmon would be a very good thing for SRKWs and help address what scientist consider orca’s biggest threat: lack of a sufficient prey base to support their survival and recovery.
The study’s abstract below nicely summarizes the study’s findings, followed by a link to the full study.
Assessing the coastal occurrence of endangered killer whales using autonomous passive acoustic recorders.
By M. Bradley Hanson, Candice K. Emmons, and Eric J. Ward
Journal of the Acoustical Society of America, November 2013.
Using moored autonomous acoustic recorders to detect and record the vocalizations of social odonotocetes to determine their occurrence patterns is a non-invasive tool in the study of these species in remote locations. Acoustic recorders were deployed in seven locations on the continental shelf of the U.S. west coast from Cape Flattery, WA to Pt. Reyes, CA to detect and record endangered southern resident killer whales between January and June of 2006–2011. Detection rates of these whales were greater in 2009 and 2011 than in 2006–2008, were most common in the month of March, and occurred with the greatest frequency off the Columbia River and Westport, which was likely related to the presence of their most commonly consumed prey, Chinook salmon. The observed patterns of annual and monthly killer whale occurrence may be related to run strength and run timing, respectively, for spring Chinook returning to the Columbia River, the largest run in this region at this time of year. Acoustic recorders provided a unique, long-term, dataset that will be important to inform future consideration of Critical Habitat designation for this U.S. Endangered Species Act listed species.
You can read the full study here.
Orca advocates, businesses and scientists call on Governor Inslee to take action to rebuild endangered chinook salmon stocks.
From the desk of Howard Garrett, Director of Orca Network
Jan 13, 2014
Thousands of years ago, when the ancestors of today’s Southern Resident orcas moved into the newly thawed Salish Sea, they learned they could depend almost entirely on chinook salmon for food. Then chinook were plentiful, huge and packed with calories, not toxins.
Now chinook are smaller and far fewer, and though orcas scan every current and crevice for miles around, during times of scarcity they can’t find enough to sustain themselves, and some of them inevitably starve. By tradition, they share their fish with the youngest and oldest family members, raising mortalities among otherwise healthy adults.
By 2001 this extended orca family had dropped to just 78 members. Today there are but 80.
Watching Our Waterways: Orca-tagging project comes to an end for now
April 5th, 2013 by Chris Dunagan
A research project that involved tracking the travels of K pod for more than three months in the Pacific Ocean apparently has ended, as the transmitter seems to have run out of battery power, according to research biologist Brad Hanson.
“This has been a phenomenal deployment,” Brad told me yesterday after it appeared he had logged the final transmission from K-25. “It has been a quantum leap forward for us in terms of understanding what is going on.”
K-25 is a 22-year-old male orca who was implanted with a satellite tag on Dec. 29. The battery was expected to last for 32,000 transmissions, and it actually reached about 35,000, said Hanson of NOAA’s Northwest Fisheries Science Center. No data arrived yesterday during the normal transmission period.
The three months of satellite tracking data will be combined with fecal and prey samples from a 10-day research cruise to serve up a wealth of information about where the Southern Resident killer whales go and what they eat during the early part of the year, Brad said. Until now, this has been a major blank spot in the understanding of these whales, he noted.
The information gathered over the past three months should prove valuable in management efforts to protect and restore these orcas, which are familiar to human residents of the Puget Sound region. After the data are analyzed, federal officials should be able to say whether they have enough information to expand “critical habitat” into coastal areas for the endangered killer whales. If not, we should know what additional information may be required.
Revealing new data shows killer whales' winter affinity for the Columbia River mouth
From the desk of Howard Garrett, co-director of Orcanetwork
Seeing orcas cruising by seems to bring out the best in people, and many residents around Puget Sound and beyond are often thrilled to see members of an extended family known as the Southern resident orcas (J, K, and L pods) foraging and playing in the waters of the Puget Sound. Watching orcas is like a drug-free mood lifter. People seem to open their eyes wide, smile and share their excitement when viewing the huge, graceful whales travelling in tight family groups, rising up to look around, or leaping clear out of the water in a mighty breach. Since the mid-1970s this tight-knit orca community has been the most watched and studied population of cetaceans on the planet. Researchers and fans alike have learned to recognize each individual whale, year after year, including their family histories.
This particular clan of orcas is precariously close to extinction, however, largely due to the scarcity of chinook salmon, their primary, traditional food source. Chinook comprise about 80% of their diet, along with a side dish of chum salmon during fall months. These orcas refuse to deviate from that menu even when faced with starvation, as was shown by the drastically ramped up mortalities between 1995 and 2001 that correlated closely with region-wide declines in chinook numbers. The resulting 20 percent drop in the population to only 78 individuals in 2001 prompted the listing of this distinct population as endangered under the ESA in November, 2005. The most recent official count shows only 84 individuals.
Most of the dietary studies have been done in summer months around the San Juan Islands, where these orcas are easily found chomping on Fraser River chinook from late spring to early fall. They tend to spend winter and spring at sea, however, and until recently there was very little clear data on where they go or what they are eating in the open ocean waters.
Will The Obama Administration Act In Behalf Of Orcas And Salmon?
- a three part series by Howard Garrett
- Dec 01, 2009 - "Commercial Fisheries, Salmon, and Orcas" - by Candace Calloway Whiting in the Seattle PI's City Brights
- Nov 17, 2009 - "River of Renewal"- Salmon, Dams, Orcas, and You
- Jun 10, 2009 - Orca Awareness Month
- Mar 03, 2009 - Saving Snake River salmon will save Puget Sound killer whales