Thursday, July 31, 2014

July 29 and 30 Js and Ks, More Data

On Tuesday the 29th the whales happened to cooperate almost perfectly with my half-day work schedule. I got out to Lime Kiln early afternoon in the middle of a passby as parts of all three pods headed north. While I did miss J2 Granny, I was there for what ended up being the closest groups - again there were whales right off the rocks!

Another perspective of shore-based whale watchers at Lime Kiln

It was still early enough that the lighting was nice to see those saddle patches that each whale can be identified by. If I were putting together an ID guide, these might be a couple of worthy shots to include:

J37 Hy'Shqa

J41 Eclipse - my favorite whale! She's grown so much I wasn't even positive this was her at first
J37 Hy'shqa and calf J49 T'ilem I'nges have been very photogenic whales this summer - at least I've had lots of opportunities to photograph them! If you're wondering about the names, all the descendents of J14 Samish are given names in traditional naming ceremonies by the Samish Indian Nation. Hy'shqa is J14's daugher, and her name means "blessing" or "thank you". T'ilem I'nges is J14's first grandchild, and appropriately, his name means "singing grandchild".

J37 Hy'shqa and J49 T'ilem I'nges
Right after the J14s were the K14s, including adult male K26 Lobo:


Following the K14s were three of the K12s, and they got up to just past the lighthouse before stopping and milling for a while. They eventually headed back south, to join up with many more whales there were still south of Lime Kiln, and a few Ls went south later to join them.

On the 30th, all the whales that had remained off the south end - partial members of all three pods - headed west back out to the open ocean. Remaining in inland waters then were the traditional J-Pod "Group A" with L87 and the K14s. So interesting to have just one K-Pod matriline hanging out with J2 Granny's group. All the whales were making their way down Boundary Pass in the early afternoon, but then yet another split happened. The Js and L87 went right back up Swanson Channel, while the K14s turned south down Haro Strait towards San Juan Island. (By the way, if you're not familiar with the area and want to follow along when I'm referencing all these different places, back in 2008 I posted a map on my blog with all the common areas marked - check it out here.)

I was again at Lime Kiln waiting for them to approach, and I was blown away by the number of people at the park also patiently waiting for these four whales to arrive! Bucking a strong flood tide, the whales made very slow progress, but dozens of people stayed out in the harsh sunshine and chilly wind waiting and waiting and waiting. They were finally rewarded, as K14 Lea and her three offspring arrived, and slllllooooooowwwwly made their way south. I think it took them about two hours to really pass by Lime Kiln.

K26 Lobo ~ "The Lone Wolf" as titled by a friend of mine

So since J-Pod arrived on May 31st we've had all these different groupings of whales coming and going, with different numbers and different whales here all the time. I'm convinced their presence or absence ultimately has to do with fish, but I know they are socially and culturally complex animals, so their travel routes are probably not simple to explain. Still, I was curious just how well the number of whales present this year has been relating to Chinook salmon numbers, particularly the Albion test catch fishery that has been receiving so much attention from local whale watchers this season. That meant tonight it was time to put my data mining hat back on and see what I could come up with.

First of all, I did the best I could at reconstructing how many whales were here each day of the last two months. I knew I had to do this now - I do take some notes on what's going on and what I see, but the days really do start to blend together. So keep in mind the number of whales present each day is my best estimate. In my first graph, I compared this number (total number of whales in inland waters) to the catch per unit effort (CPUE) for that day on the Albion test catch fishery. Some people believe it's more accurate to compare delayed test catch numbers - for instance 1-4 days later, as it takes the salmon some time to travel from a place like Lime Kiln to the Albion test catch site - but because we don't really know how long this takes a fish, I decided to do a direct same-day comparison of whale numbers to test catch numbers. Here are the results:

X-axis shows the number of whales present in inland waters (ranging from 0 to 69, the most whales we've had "in" at once this year); Y-axis shows the Albion test fishery catch per unit effort value, which corrects how many fish they caught that day by how much effort they put into trying to catch fish. I added a blue trend line. The R-squared value, which is a statistical measure of how well data fit a regression line, is .23 - not excellent, but there's definitely some trend there. Makes sense - this graph basically says when there's more whales around, there's usually more fish around.

What the above graph doesn't capture, however, is how things have played out on a daily basis over these last two months. I wanted to see how the two values compared on a daily basis from May 31 to July 31, so this graph shows each value as it's own color on a bar graph.

The X-axis takes us from May 31st to July 31st of this year. Number of whales present in inland waters (or my best estimation of this number) is indicated by the blue lines and reference the left Y-axis. Albion Chinook test catch CPUE numbers are shown in the orange bars and values can be read off the right Y-axis. Again you see a faint trend of what you would expect - higher CPUE numbers generally translate into more whales present.


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