NOAA synopsis of 2006 SRKW symposium

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The following synopsis of the 2006 SRKW symposium was published on April 08, 2006, at
the web site of the NOAA Fisheries Service (Northwest Fisheries Science Center, author unknown):

“The Center kicked off the 75th anniversary of the Montlake laboratory with an international orca symposium on April 3-5. “Southern resident killer whales are the most studied cetaceans on earth,” said Dr. Linda Jones, yet several data gaps still exist. Dr. Jones was honored by NOAA Fisheries and the Washington Department of Fish and Wildlife for her outstanding leadership at the helm of the Center’s marine mammal program, now led by Dr. Michael Ford. During her over 30-year tenure, Jones oversaw more than $5 million in federally-sponsored research projects, including some of the genetic studies that ultimately led to the orca’s recent listing as an endangered species. Over 200 people attended the orca symposium to discuss state-of-the art research and data gaps regarding the risk factors affecting orca decline (contaminants, noise, vessel traffic, and decline of prey species such as Chinook salmon).”

Brad Hanson on orca diet

Monster Jam, Brad Hanson, 07/04/05

Diet of southern resident killer whales

Inferences from prey samples and sensors deployed on killer whales
Time-depth-recorder deployments in southern residents

  • Baird and Hansen+? (2005) J Canadian Zoology
  • 40 deployments from 1993-2002
  • ~10.5 minutes median record duration
  • L87 Haro Strait example record: 2 dives to 100m with velocity spikes near deepest point; 2 dives to 20m with velocity spikes (~4m/s peak)
  • overall bimodal distribution with most dives to 25m or 100-150m…
  • compare with fisheries data: Quinn says sockeye usually at 16m, Chinook ~70m; Horne says larger echosounder targets are common at 100m (trawl there gave dogfish and juvenile salmon)

2002 crittercam on J25 (1.5 hr data total) example from S Lopez

  • Blows bubbles before surfacing
  • Blow hole puckers during vocalization

Foraging behavior (samples/behavior metric) is more often defined by low energy behavior (slow convergence) than high

Molecular Genetic analysis
(scales and tissue ~77 samples; about 150 if you include fecal, mucous, regurgitations)

Most samples collected N/S of false bay, SJI

Primary seasonal prey species:

  • Chinook (primarily in June-Aug)
  • Little data from Sept/oct
  • Chum in Oct/Nov/Dec
  • NO sockeye or pinks
  • ==> are seals and orcas partitioning resources?

From which river systems did the ingested chinook come? (L. Weitkamp, unpublished)
base on (genetic sampling) via coded wire tag program?

  • May: southern puget sound fish! (only one Fraser)
  • June-Sept:
  1. Predominance of Fraser
  2. upper fraser first in  mid Jun-aug; then South Thompson;  then mixed in Sept
  3. One central valley ca
  4. Some N sound, but minimal S sound

Fecal data from sep and oct and nov include evidence of dover sole and lingcod

Planned collections in 2007: June and Sept
Desire for May and Oct collections