Beam Reach

Has someone shot J pod?

It is disconcerting to me that J pod did not re-visit the west side of San Juan Island during the first two-week research cruise of the spring Beam Reach program. I joined the ship last Thursday fully expecting our fish tagging exercise to be interrupted by the returning southern residents. There was even a tantalizing missive from the respective American and Canadian killer whale God-fathers (from Ken Balcomb with allusions to John Ford) the previous day:

“Thursday, 1 May 2008 @ 13:41 …somewhere between here and Nanaimo there are 12-15 other whales that were heading south past John Ford’s house at sunset last night. It is about an 18 hour trip typically from there, so we could see whales any moment.”

But we were off Lime Kiln on Thursday and Friday and heard nothing but lingcod depth measurements. And so I returned to Seattle and listened fervently through the weekend — Port Townsend in one ear, Lime Kiln or OrcaSound in the other. I heard a lot of ships and noted that something seems to be beating the PT hydrophone during peak current flow, but there were no familiar calls or clicks.

Thus, I’m up late re-visiting my previous analysis of the historical sighting data. The general pattern is that there aren’t many days when southern residents are sighted (or heard) in Haro Strait during March, but the sightings per month steadily increase from April through June.

We designed the spring Beam Reach curriculum around these data which suggest that there is high likelihood of getting some preliminary data from J pod during the final two weeks of April. Analysis of the archives confirms that there are typically more sightings at the end of April than during the beginning.

Of course, our diligent (and patient!) students are now back on land analyzing simulated data sets so they’ll be ready for the arrival of J pod in May. We’re now about a week into May and J pod hasn’t been definitively sighted in the Salish Sea for nearly a month. When last seen on April 8th at 2pm, they were heading southwestward from Hein Bank into the Strait of Juan de Fuca, gateway to the Northeast Pacific.

Who else will be worried if they don’t return by this Thursday? The trend in sightings per month is hinting that 2008 is shaping up to be an unusual year. While March sightings were about average, April sightings were the lowest observed in the last 7 years. (There may be biases in these values, but if anything the sighting effort was less in the past, so older values are expected to be relatively low — not high!) Will May set a record low as well?

All this has me wondering what is going on out there. Has something appalling happened, akin to the surreptitious killing of California and Stellar sea lions in the Columbia River on Sunday? Or is there a problem with the fish that the residents prefer to eat: salmon, and Chinook in particular? We know that the California runs have essentially failed this year, with the commercial Chinook fishery mostly closed along the West Coast for the first time in more than 40 years.

Surprisingly, it’s proving very difficult (even for an oceanographer like me) to get a coherent overview of what marine fish are around Puget Sound. The data I’ve found and ways Beam Reach is helping to fill the gaps are the topic of my next post…