While the net weir has been up for awhile now I have yet to mention it in my blog, partially because it’s purpose is kind of hard to explain and partially because it has yet to give us any conclusive data. Because I don’t really feel like taking the time to explain it I’ll give a short explanation with some pictures that will hopefully at least make it look interesting. Ben Van Allen, the net weir expert, and his assistant Carol, both from Juneau, flew in a month or so ago to assist us with net weir construction and positioning. In his fifties, Ben is one of the hardest workers I’ve met, getting up an hour before the rest of us, working without breaks or food and going to bed late into the night, never stopping until the job’s done. Subsequently, Laura and I ended up assuming the position of “sustenance providers” while the others worked (there’s only room for three in a boat anyways).
Net Weir 101: The net weir is positioned behind the picket weir and it’s purpose is to validate our fish escapement numbers, e.g. make sure the weir is fish-tight and that extra fish aren’t getting through holes and thus not being counted. The net weir has a motion-activated camera that fish are funneled past and the hope is that the same amount of fish that we count going through the picket weir will coincide with the number of fish picked-up by the camera. This a whole bunch of percentage stuff and adipose fin cutting, but I won’t get into that. However, since setup we have had multiple problems with this project, ranging from a bear knocking our camera equipment into the water to malfunctioning playback equipment, and worst of all, only five salmon showing up on the video in a month – hmmmm… Where are they all going…? So we moved the net and started over a few weeks ago, we’ll see how it goes.
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