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Posts: 507
| Steve,
Here's a summary of the netting on Nancy Lake this year. The netting was initiated as a result of discussion within the statewide muskellunge management standing team. During the discussion, we determined that we were willing to go forward with an evaluation comparing performance of Leech L and Chip R fish in Wisconsin waters that contained no native, self-sustaining population. Part of the discussion concerned source of fish for the evaluation. Given that Nancy L was the only lake in the state with LL muskie, we conducted a netting survey with the objective of assessing feasibility of using Nancy L as a source of eggs for hatchery production.
Six nets were set on 4/12. Three additional nets were set on 4/13. We moved a couple of nets around during the sampling. We put nets anywhere that Terry Margenau or Larry Damman had reported capturing fish in the past. As Tim reported, we conducted 78 net lifts and captured 6 fish. All fish were netted in the large basin in the NE part of the lake (off the point along S shore, and off a rocky shore in SE part of the basin.
4/15 male 46.1" RV clip
4/19 male 45.5" LV clip
female 47.5" RV clip
4/20 female 48.6" no clip
4/21 female 49.7" RV clip
4/22 female 43.2" no clip
The last nets were pulled on 4/23. Water temperatures in the deep basin near the landing were 55 degrees.
We determined that the population density was not sufficient to justify attempting to take eggs for hatchery production. With a small population, we would run into risks of inbreeding depression. In addition, finding a fish or two each day would probably lead to holding in fish overnight for spawining (to get one of each gender), further stressing the fish. We also determined that with these low numbers, completing a population estimate by netting next year would not be the best use of staff time. For the purposes of obtaining eggs for an evaluation, we determined that going to MDNR would be the best option.
The clips suggest that some of the fish were stocked. During 1984 and 1990, stocked fish were given RV clips; during 1987 fish were given LV clips. The two fish without clips are probably the result of natural reproduction.
I hope this information answers your questions. If not, I'd be glad to discuss it further.
P Martin J. Jennings
Northern Lakes Ecologist
Fisheries and Aquatic Sciences Research
Bureau of Integrated Science Services
Wisconsin Department of Natural Resources
(() phone: (715) 635-4160
(() fax: (715) 635-4105
(+) e-mail: [email protected]
Original work on Nancy Lkae, read the entire report and apply it to what's posted here:
http://www.dnr.state.wi.us/org/es/science/publications/PUBL_SS_575_... |
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Posts: 507
| I also spoke and communicated via email with Mr. Simonson about this issue. The WIDNR feels the Nancy Lake Leech Lake strain fish did reproduce, but in such low numbers as not sustain a successful fishery, and certainly not create a brood stock lake. The numbers stocked should certainly have been sufficient to get the job done had the fish adapted as well as hoped.
Here is a short communication regarding this issue:
'Steve - We did survey Nancy Lake this spring. Marty Jennings, Spooner, conducted the survey. He would be your best contact ([email protected]). Here is a brief summary from our May meeting (taken from our web page: http://dnr.wi.gov/org/water/fhp/fish/musky/muskymanteam.html)
Update on Nancy Lake findings - Marty Jennings provided an update on his survey efforts in Nancy Lake this spring. They captured 6 Leech Lake muskellunge from about 43 to 49 inches in 78 net lifts (0.08 fish/lift). It was concluded that the population is not of sufficient size to serve as a brood stock if the intent is to establish naturally reproducing populations. Efforts will be made to obtain eggs or fry from Minnesota DNR.
Hope this helps. Not much evidence of natural reproduction. Marty has the records on how many of the fish were marked. We have some other surveys from Nancy (Margenau and Larry Damman) that may shed light on the NR component, but as I recall, there wasn't much. ' |
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Posts: 507
| Mr. Diana, University of Michiagn (General Session Symposium presentation: Human influences on natural spawning), on the subject of coexistence between Northern Pike and Muskellunge in Inland Lakes in Wisconsin and genetic strains, Panel Discussion, Genetics section of the discussion, apparently in respone to another panel emebers comments about Northenr Pike competition in Wisconsin Stocked lakes:
Mr. Heiting asking for perspective on 'Superior strains of Muskellunge': "Mr. Diana, do you have any perspective on this please?"
Mr. Diana: " Well, just to bring this to a different point and that has to do with the coexistence of pike and muskellunge. I don’t think there is any evidence we have to say that a strain that is comfortable in location where both pike and muskellunge exist, will have any better capability surviving in the long-run in a new situation with pike. I think that we need better research on that coexistence and what causes one or the other to become dominant, but at this point we really don’t know, and I don’t think you can say that the Leech Lake strain will be any better in an inland lake in dealing with pike as a competitor than would the Wisconsin strain. "
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