Orcasphere

Gregg Schorr for Brad, dive behavior Is dive depth related to prey preference? Do dive rates vary between pods, day/night, years? Is frequency of max dive depth constant over time? Prey field mapping in Sept, 2004 (after sockeye, during fall Chinook run): big targets are near middle of water column (>100m); prey assemblages different in [...]

Pete for Steve Rafferty, epidemiological and pathologic findings Only 10/81 confirmed SR deaths and 4/142 of NR were beach cast and available for post-mortem examination.  Infectious pneumonia is most common reported cause of mortality (60% of those necropsied).  We now have a standardized protocol for doing necropsies (available at http://seadocsociety.org)  Since 2002, Steve and Joe [...]

Sandra O’Neill, Contaminants in salmon We’ve heard that S and N residents are both eating mostly Chinook.  Why are the southern residents more contaminated than the northern residents? Contaminants in fish are determined by: where they live what they eat how long they are exposed how fat they are Chinook and Coho have elevated [PBDE] [...]

8:35 John Ford, resident KW foraging ecology What may have caused the simultaneous declines in the N and S residents during the late 1990s?  Nutritional stress? We compared expected and observed births and deaths, where expectations were based on period of unlimited growth (’73-’90).  There were two phases of increased mortality in adult/juvenile fe/males: late [...]

14:55 Val Veirs giving Marla’s talk on “Vocal Compensation in SRKWs” Background noise levels had mean of 110.1 DB +/- 4.1; range 98-123dB Call source level: mean of 55.3dB +/-7.4 dB Lombard effect in SRKWs is present; ~1dB increase in S1 call source level for every 1dB increase in ambient noise level ambient noise increases [...]

First there was Mike Bigg.  Early census effort started in 1976 and was motivated by concern about the captures for aquariums which took out about 50 animals.  1976-1984 habitat use was very similar to current critical habitat!  Most encounters May-October, with J pod present year-round. Ken and Mike worried about how to ID babies.  They [...]

10:00 Lynne Barre, NWFSC Critical habitat can be modified.  A future step is designating habitat outside of the inland waters of WA. Recovery plan implementation was started in 2003, well before the endangered listing in 2005. Proposed regulations are under review… no date given for when rule-making will occur. Consultations regarding potential impacts result in [...]

Just got an exciting email from Dr. Marla Holt, bioacoustician on the NOAA cruise that aims to understand how the southern residents utilize the outer coast of Washington. They departed last Monday and are scheduled to return April 9th, making for a significantly longer cruise than in past years. Since big ocean-going research boats like [...]

Persistent organic pollutants as chemical tracers for Puget Sound marine biota, Gina Ylitalo Chemical tracers can be used to determine geographic ranges.  Persistent organic pollutants (POPs) like PCBs and PDBEs in Salish Sea herring (3 yr old males collected ’99 and ’04) showed elevated levels in Puget Sound relative to Georgia Strait, though difference was [...]

Eric Beamer, Juvenile Chinook salmon use of small non-natal estuaries  in the Whidbey Basin, eastern Admiralty Inlet, and the San Juan Islands Most of our juveniles are coming from the Skagit, accumulating early in the year (feb-may, some years as early as december, often associated with floods).  Pocket estuaries are safer places (most fish are [...]