We've been working hard out here pulling double-duty on bull trout and burbot. The bull trout fishing slowed quite a bit which was a bummer (haven't reached the sample size goal), but the burbot trapping seems to be picking up.
Burbot are quite sensitive to barotrauma, which occurs when fish are brought up from depth too quickly. When a fish is down in the water column somewhere, there is pressure pushing on the fish. At 33 feet it would be 2X the pressure we feel on the surface. If a fish does not resist that pressure somehow, it would be crushed. So, they do resist by creating internal pressure which equals the surrounding pressure. However, when brought up quickly from depth the outside pressure decreases while the internal pressure remains the same and thus causes the air bladder to puff out, or in some cases cause stomachs to distend and other organs to be pushed out. Most of the burbot have experience some degree of barotrauma (no organs have been pushed out, but lots of distended bellies and large air bladders). To combat this, the PhD student doing the burbot work (Phil Harrison from the University of Waterloo) does frequent decompression stops, and will sometimes "recompress" burbot after performing surgery on them. So far, things have been quite successful.
After recompressing, Mr. Burbot is released.
More muskie stuff to come soon. Next up on the agenda is to give a presentation to the Capital Muskies Club in Ottawa (http://www.capitalmuskies.ca) on May 26th.
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