“Seeing” What Killer Whales VisualizeLatest update August 4, 2019 Started on November 4, 2018
Decline of prey, specifically Chinook salmon, has been identified as a threat to the recovery of the Southern Resident Killer Whale population in Canada and the US. However, little is known about whether there are enough fish for them to prey upon. Our mission is to determine how many Chinook are present and how the fish are distributed in areas where increasing and decreasing populations of fish-eating killer whales travel and feed. We are pursuing this goal using sound to visualize life beneath the surface water. Our study will contribute to the recovery of Southern Resident Killer Whales by assessing the availability of prey in habitats used by killer whales.
We finished all the CTD stations today. With a help of small capstan, Kiah Lee (undergraduate student majoring oceanography) deployed 42 casts over three weeks as deep as 400-m depth, rain or shine. The total length of rope she worked on was 13-km. Great job, Kiah!
We finally got a large Chinook (~ 75 cm) in Johnstone Strait! Jacob Lerner, Ph.D student, will look at how much calories they provide to killer whales and whether there is any difference in fat content of Chinook salmon we caught in southern and northern resident killer whale habitats.
Today, all of our fish on the lines got eaten! She showed up for lunch and dinner and we only got 1 fish at the end… We saw her taking a deep breath for a few times before long dives. She even ate our fish in front of us, while we were recovering the fishing lines.
(Photo credit: Kiah Lee)