Archive for May 1st, 2010

Dall’s porpoises and hydrophone calibration

Prevost Harbor to Mitchell Bay

Since J Pod is back in town, our main goal today was to find the whales. We started drifting down the west side of San Juan Island hoping we’d find them in Haro Strait. Around 10 am, several Dall’s porpoises surfaced off of Gato Verde’s stern. Recently, Dall’s sightings have been few and far between, so it was very exciting to see them! Once we had passed Lime Kiln Point State Park without any whale sightings, we decided to calibrate our hydrophones (the array, the “blue box,” and the flat-frequency hydrophone). We rigged them up side by side and lowered them 5 meters below the surface. We made several successful recordings. Later in the afternoon, we decided to try to search for the south hydrophone array with the Splashcam. Unfortunately we had technical difficulties and had to abort our mission, but Jason solved the problem and we will likely try to deploy the Splashcam again soon. After a morning and afternoon of no whales, we made the executive decision to start working our way back up the west side to find someplace to anchor for the night. The Southern residents seem to be swimming clockwise around the San Juan Islands, and we are hoping they’ll loop back around to Haro Strait tomorrow.

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