Beam Reach

Radio: Orcas visit Puget Sound

Your host Martha Baskin

Martha Baskin of Green Acre Radio (on KBCS) put together a story about “Orcafest 2010,” an event welcoming the southern resident killer whales back to Puget Sound this winter, organized by The Whale Trail and Killer Whale Tales.  The piece features music and explanations from Duwamish tribal members, and quotes about the orcas from Donna Sandstrom, Darcie Larson, Scott Veirs, and Brad Hanson.

Social fluidity….increasing betweenness levels

During our great and enlightening journal club discussions, in which each student leads the discussion on one of the seminal articles for their own project, we learned some new categories used to estimate the extent of the social role that a given individual can exert over a group. One of this categories is known as “betweenness” and it measures how often a given individual is found in between clusters. An individual with a high level of “betweenness” is then expected to be an “information broker” in cetacean societies. Another related category is known as “degree.” The degree of an individual is the measurement of its influence on its peers.

The betweenness and degree levels of our SRKWs has never been fully studied. However, during our research we were lucky enough to catch some of these interactions. Our photographic record revealed some of these events, in which matrilines across pods mixed with each other or individual whales joined different matrilines. 

Some of the biggest “wonderers” observed during our 5 weeks at sea were J27 (male), J1 (male), K21 (male), L 77 (female), L72 (female). 

Here are some of those images:

Dall’s porpoises flirting with danger……

Dall’s porpoises flirting with danger……

Flat, mirror like waters were suddenly broken by the splash of Dall’s porpoises swimming around a large male killer whale. These creatures seem to have the adrenaline-addiction gene. Riding the bow wave of an orca is not exactly the best idea for a cetacean one seventh of their size. Although our resident whales are fish eaters, there have been accounts of instances in which southern residents have killed Dall’s porpoises while at play. Whether a challenge or a game, the Dall’s seemed the most interested in the interaction as the killer whale seemed to zig-zag her path trying to shake them off.

Whatever the reasons behind this dangerous game, to us humans it was like seeing a mini-orca and a full sized one side to side, sizing each other up, comparing dorsals, comparing speed…or perhaps simply having a profound inter-species recognition. Dall’s have never been preyed upon by southern resident killer whales, so it is conceivable that the few deaths reported from “play-like” interactions were just unfortunate consequences from the orca’s inability to measure its own strength against their much smaller “play-mate”. The short, playfull and peaceful  interaction we were able to witness was certainly awe inspiring.

(images in uploading process, server errors)