After almost 6 long hours of scanning the seemingly empty ocean surface we finally sighted a group of about 25 short-finned pilot whales. We approached the group and began taking dorsal identification photographs while assessing their general behavior. Brenda Rhone of Cascadia Research was able to search the photo identification database on board and confirmed there were several known individuals in the group. Moreover, the group was also being quite cooperative so we decided to attempt to deploy a DTAG, and then another, and another!
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Slowly approaching a small subgroup to get in to position to attach a DTAG |
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Daniel Webster, of Cascadia Research, reaching over for the suction cup attachment (NMFS permit # 15530 to CRC). |
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Success! This is one of the three individuals we tagged. Notice the distinctive markings and trailing edge on the dorsal fin of the tagged individual. This was helpful in visually locating the animal when it was at the surface (NMFS permit # 15530 to CRC). |
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A tail lobbing pilot whale in the midst of a closely associated subgroup. We are especially excited to look at our acoustic data as we are hoping that these whales were being just as acoustically active as they were being physically active (NMFS permit # 15530 to CRC). |
After 17 straight days on the water without a successful DTAG deployment, three pilot whales were finally wearing our tags. Along with the acoustic, movement, and dive data that the tags were recording directly on the animals we also deployed another acoustic recorder, the Drifter, which is attached to a floating buoy and suspended at a constant depth. We observed the group of pilot whales swimming around our Drifter on many occasions throughout the encounter, and if they were acoustically active, we now have data from several hydrophones to compare!
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One of our tagged animals spyhopping, possibly for a better view (NMFS permit # 15530 to CRC).. |
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Dr. Mooney using the Yagi, a directional antenna, to listen to the VHF signals that the DTAG emits, which allow us to pinpoint it's location when it's at the surface. A very handy tool when the relatively small tag has been released from the animal and is floating on the the big blue ocean. |
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