Member
Posts: 2680
Location: Essexville, MI./Saginaw Bay. | O.K. Guys.
A few months ago on another board I posted some correspondence between me and one of our DNR biologist assigned particularily to the Saginaw Bay, concerning what he called a 31 times better trawl results for Young of the Year (YOY) walleye in 2003, than they have ever seen. Since that time I have recieved some e-mails from outdoor writers asking why some other Biologist have been calling the results 4.8 time more (YOY) in the trawl nets last fall versus the 31X number. Both the e-mail I'm posting below along with a link to the new fact sheet that the DNR just came out with today should explain the whole thing. The results are still exciting if things stay status quo.
Dan:
There's been no change in our numbers as a result of our meeting. We did decide, however, that the statistic of 31x increase in walleye young-of-the-year (YOY) over the average of past years is too prone to misunderstanding without a lot of extra explanation. For example, there were many years where there were little or no YOY produced. We decided that a better way to express the strength of the 2003 Saginaw Bay walleye year-class is in terms of how it compares to our past record year class which was 1998. More people might be familiar with what that is like, as it is more recent and is currently a big part of our fishery. The 2003 year class is 4.8x as much as it was in 1998 when measured at the YOY stage. This is the same data as the 31x number but just expressed in a way that we think will help ensure that everyone's expectations don't get blown out of proportion. The more important point to remember is that we won't make our final judgements on what the year class strength is until we can measure it at the yearling size next September. By that time, any over-winter mortality will have occurred and we'll see what we are actually left with for the remainder of that year class.
The Fisheries Division of the DNR is preparing a fact sheet on the subject and we'll likely post it on the Department's web site later in March. That fact sheet will probably detail these sort of numbers. I suggest you hold off from posting any information until we have that fact sheet in place. I'll let you know when that is. If it comes up in conversation, I suggest you use the 4.8x description (comparison to our past record year of 1998) and remember to remind people that the final year class strength won't be set until after this winter. In other words things could still change.
On a related note, the 2003 yellow perch year class (which was also a new record) was 3.4x the previous record set back in 1982. That same uncertainties apply to that measurement and they may be even more prone to some over-winter losses than the walleye are.
The new DNR fact sheet link address is: http://www.michigandnr.com/PUBLICATIONS/PDFS/fishing/SB_Perch_walle...
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Saginaw Bays final fact sheet on last years walleye production.