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View Full Version : TFF Survey - DNR's First Impressions



BlueRanger
05-05-2009, 06:43 PM
I received an email from our Fisheries Biologist Jeff Roth today, and I'll reprint exactly what he said with the caveat that these are only his general impressions based on what he saw on the water. As I said before, the creel census will continue through the end of the ice season, so don't expect the formal report until next year. But hopefully he'll be willing to share more details of the survey results in a couple months after the data is analyzed.

Just recovering from the TFF survey. Many 15 hours days netting and shocking. We netted and [recaptured] the Manitowish River and Bonies Mound area where walleye spawn first even before the ice is out on the rest of the flowage. We then moved into Trude Lake and the rest of the flowage with the goal of having our work done before the opener. The data is extensive and I have not had a chance to go through it yet but can say that the walleye size structure in the flowage is as good or better than in the past. The size structure on Trude Lake "appears" worse than years ago, but this is just a "gut" reaction without direct data comparison. Walleye abundance appears higher but with smaller fish. The largest walleye sampled was 30 inches with the best size structure found in the "big water" area of the flowage. The majority (if not all) male walleyes ran 15 to 20 inches there. Doesn't get any better than that.

Musky were impressive with good total numbers and improved size structure. Many (%?) over 40 inches with numerous fish 45 to 49 inches. The largest fish so far at 49". We are still sampling for musky in a few areas and will be following up in a few weeks with a smallmouth bass sample.

St Croix Kid
05-05-2009, 08:46 PM
what is the feeling about mortality rates of fish that are shocked for the survey. heard some people mention this weekend that it may be higher than the DNR is willing to admit. would be interested to get some thoughts on that.

gus
05-05-2009, 09:55 PM
Blue,
Thats great info.Sounds pretty positive.Thanks for sharing this with us.

Nick Kanauz
05-06-2009, 01:57 PM
SCK-
The Michigan DNR released data taken here on the Muskegon River, where they take most if not all of their eggs for the year's stocking. They actually kill up to 20% of the fish taken to sample test for invasive infections, parasites, and reproductive aging.
According to their records, a 5 to 10% mortality is common on shocked fish, with most of the mortality in younger fish. Once shocked, the fish are actually put in a trough with an anesthetic & antibiotics to one, allow them to milk the fish for sperm & eggs, and to help them avoid any virus from human handling. They are then placed in a trough with fresh water running through it until they regain their strength, and are then released. They have no real data on the fish once they are released, saying only that they know immediately which fish have succombed.
I would imagine that this would also apply to the Wisconsin DNR since they rely on the use of boom shockers as well.
This info came straight from our Outdoor Editor here at The Press. He had just come back from a trip with the DNR, and gave me the info straight from his notes. He had some really great pictures of the program in progress as well.
Hope this helps a little.
Best fishes,
Tracker
<>< :)

St Croix Kid
05-06-2009, 02:47 PM
thanks Nick. good luck this weekend. the flowage was very ,very good to us last weekend