It seems like every other day there's a news story on Humboldt squid, jumbo squid, or (my favorite!) giant squid. (D. gigas is still not a giant squid.) I haven't been covering all of these articles here because, well . . . I didn't want to be a diva by association.
But this article is the most thorough I've seen yet, including all the interviews and topics that have been covered piecemeal in earlier articles, so it seemed like a good time to jump in and clarify a few items.
Item One: It's not strictly true to say that Humboldt squid "generally keep to deep water," but I understand where the confusion comes in. Vertical migration is a rather bizarre concept. Here in our mostly two-dimensional terrestrial world, we're much more familiar with the idea of horizontal migration. So, the squid do live in deep water, but they also live in very shallow water, and they go back and forth between the two. A comparable vertical migration on land would be hiking to Yosemite's Upper Cathedral Lake and back. Every day.
Kent Baltz, a National Oceanic and Atmospheric Administration oceanographer in Santa Cruz, Calif., suspects that the lower salinity of the water in the Strait could be hard on the squid. “Squid are highly sensitive to water conditions, very sensitive to pH” — a measure of the acidity or basicity of a solution — he said, pointing out that water in the Strait is generally more diluted by freshwater and has more sediment than that in open ocean.Sigh. His name is Ken, not Kent. Again, I do see that the concepts here are not the easiest to communicate, but this reads to me like a conflation of salinity and pH. Which are very much not the same thing. Salinity is a measure of how much salt is dissolved in the water. (The salinity of truly fresh water is zero; the average salinity of the ocean is 35.) Yes, pH is in fact a measure of "acidity or basicity," or, put differently, a measure of hydrogen ions dissolved in the water. (Orange juice has an acidic pH of about 4; bleach is basic at about 12.) I don't know anything about the pH of the Strait.
I suspect that Ken was simply using pH as an example of another water condition (in addition to salinity) to which squid are known to be sensitive, not suggesting that it is a factor in this squid beaching.
Item Three: "Usually, squid die in the winter. California researchers expect die-offs of squid in February or March." That is interesting! I, a California researcher, did not know that! Squid beachings in SoCal have generally occurred in the summer, so that would seem to be a counterexample . . . I do not wish to be over-snarky, though, because there's always a chance I've missed some genuine scientific information.
Also, I'm not a diva.