Tuesday, July 21, 2015

July 12th: Js, Ks, and Ls, in Haro (OBI #24)

On July 12th we again got to meet up with whales right outside of Mitchell Bay, this time getting on scene right after some newly arrived whales met up with the group of Js and Ks we had seen the day before. The first whales we saw were members of the K12s and K13s.


A large group of J- and K-Pod whales then met up and got tight to the shoreline along San Juan Island. We heard there might be more whales to the south, a suspicion fueled by the fact that the whales all started porpoising in that direction. We were quite a ways offshore, but it was still impressive to see so many of them moving so quickly.

An offshore look of what was an impressive pass at Lime Kiln - between 20 and 30 whales porpoising by close to shore

Offshore a little south of Lime Kiln we met up with some of "the rest" of the whales. The first ones we saw were L47 Marina and L115 Mystic, confirming that at least part of L-Pod had come in too.

Hello L47 Marina - haven't seen you in a while!
Down by False Bay we came across even more whales, and by now all the different groups seemed to be meeting up. At first some of them seemed to be foraging, including members of the J16s and L4s. We just sat watching them for more than half an hour, and at one point L27 Ophelia surprised us by surfacing right off our bow!

L27 Ophelia, estimated to be about 50 years old

We like the opportunity to sit for an extended period with our engines off, because it gives us the chance to make longer hydrophone recordings of the whales. As these whales foraged and then headed offshore, it gave us a chance to make one of our longest boat-based recordings of the season at over 20 minutes.

There are several reasons we're keen to collect data from the whales both from the boat and from shore. Each gives us a different perspective: at shore, we're in one spot, and get to watch the whole group of whales go by, getting an idea of the entire group from a point location. On the boat, by contrast, we can stay with one group of whales for a longer period of time, watching as they chance what they do as they traverse their habitat. The recordings are also very different. At Lime Kiln, we get long recordings that capture all the vocals of the whole group as they go by, but it can be difficult to parse out which whales you're recording from or to record from one group for very long, as they tend to just swim right on by. On the boat, we can deploy the hydrophone for shorter periods of time - often less than 5 minutes - but can have a much better idea of who we're recording from. Our longer boat recording from July 12 captured the vocals of many groups of whales, but the end of the recording is one example where the only whales near us were the K22s. Some of our research questions are about the vocalizations at the matriline (instead of pod) level, and recordings like this are invaluable for those types of studies.


K33 Tika surfacing while we were recording his vocalizations

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