If you ask 100 people their opinion on any given subject you will get 100 answers, and most of them will be different. If you told all of those 100 people the five most important rock solid facts about the subject, they would give you 100 opinions and most would be different. If you asked 100 people their opinion about the quality of the fishing on Tomahawk Lake, you would get 100 answers, and 90 of the 100 would hold the opinion that the fishing in Tomahawk Lake is poor and getting worse every minute. If you asked 100 people what good fishing in Tomahawk Lake looks like, many would say it looks like fishing in the 50’s, or the 60’s, or the 70’s. I fished Tomahawk Lake in most of those years, and I can tell you that peoples recollections of fishing in the 50’s, 60’s and 70’s is a lot like my hearing… very selective! Before I became the Executive Director of the Tomahawk Lake Association in June, people would ask me “how’s fishing?” or “Are you catching any?”. Now people say to me “Fishing stinks. What are you going to do about it?” ouch!
Telling folks that my immediate answer is to pray over my worms just doesn’t cut it, so I thought I should probably find out what I could about where Tomahawk Lake’s fishing is going. One of my neighbors really helped me out by giving me a “preliminary report” of an ongoing study of fish populations in Tomahawk Lake, which came out in June of this year. The report only covers the first part of the12 month, three part study, but if the second and third part expose the same number of nerves from anglers that the first part did, it will be a really warm spring around here next year.
In early August, I called the two DNR Fisheries Biologists which are running the study, and on two separate occasions I sat down for a one on one meeting with these two scientists. They went out of their way to answer all of my questions, and to give me a better understanding of the dynamics in play under the surface of our lake. Even if I struggled to get my arms around all of the information that they gave me, I had no problem understanding that the two of them are totally committed to the long term health of the Tomahawk Lake Fishery.
The first part of the study deals with populations of adult fish only. Adult fish are defined as fish that are old enough to reproduce. The report paints a kind of a good news / bad news picture.
Based upon netting samples taken this past spring, the numbers of Small Mouth and Large Mouth Bass are growing nicely. The size distribution of these fish indicate a greater population of small to medium sized fish than large fish which to me seems to make sense. So I would say: “Small Mouth and Largemouth Bass – Good News”
Based on the netting samples taken this past spring, the numbers of Walleye and Musky however are not growing, and may be decreasing! Size distribution indicates that we have fewer small to medium sized adults, and more fish that would look dandy on a wall. While it’s great to catch a really big fish, I think that all would say it’s probably better to see lots of small to medium sized fish following those lunkers around the lake. At first Blush: “Walleyes and Musky – Bad News”
Things really start to get confusing when you start to look at “fish per acre” and “pounds per acre”. These two measures have often been used to compare populations over time.
An example might be “Lake X had an increase of 3 bass per acre between 2003 and 2006” One might think that this is a healthy trend. But what if the number of pounds per acre of bass went down over same period of time? That could mean that the larger bass in the lake are dieing off and are being replaced by small fish. Is it better to have fewer large fish and more small fish, or the other way around. Some anglers want eating size Walleyes while others want the chance at a really huge Walleye. Some want both.
Typically we come to some sort of an evaluation on the health of the fishery by looking at the dynamics of fish populations over time. The more history we have, the better our perspective will be. In Tomahawk Lake the DNR has been running periodic population studies since the early 1990’s, and there seems to be no getting around the numbers for this year. The adult fish per acre study for both Walleyes and Musky are down for the year, and are below the expected levels for a lake with natural reproduction. But, and it’s a huge “But”, there are many variables which make it hard to come to a definitive conclusion about what it all means.
Every year that the sample is taken is a “snap shot” in time. That “snap shot” doesn’t take into consideration what the weather has been like, when the ice went out, what the water temperature was, had the fish started spawning, had the fish already completed spawning
had the weeds come up, Blah Blah Blah. Every year that the population studies are taken have different answers to these questions and many more. The truth is that we are never comparing apples to apples, year to year. The only thing that can be said is that “this is what we saw this year”. Over an extended period of time, and with greater numbers of population samples taken, the accuracy of the trend lines will get better.
Remember too that the preliminary report only talks about adult fish. This fall the DNR will be taking a population sample of “Young of the Year” fish, which are those fish that are too young to reproduce. In February of 2010, the DNR will complete the Year long “Anglers Creel Census” which is the third part of the study. All three of these parts will contribute to the 2009 Comprehensive Fishery Survey for Tomahawk Lake. Based upon the survey results, in it’s entirety, the DNR will make adjustments to it’s fishery management plan for our lake.
Most people don’t know it, but The DNR has been stocking Tomahawk Lake with Walleyes and Musky’s every two or three years. In general the number of fish stocked per year has been going down. From my conversations with the biologists, I would expect that the 2010 stocking would be of larger sized fingerlings than in recent years. As the winter months play out, The Tomahawk Lake Association will be monitoring the future management plans that the DNR will be developing, and we hope to have significant input into the final plan. The DNR mandated Comprehensive Lake Management Plan (CLMP) that we developed over the past two years speaks to the goals that our lake community has indicated that they were most concerned about. We will be working with the DNR to ensure that your interests are represented.
As time goes on, and the various parts of the survey become available, I will report to you what the survey is revealing. The DNR team that is in place is committed to reversing the trend of small numbers of small to medium sized Walleyes and Musky’s, and I know that will be the greatest priority in their management plan (“Trust but verify” Ronald Reagan)
Now isn’t this all clear as mud? In this edition of the Executive Directors Blog I’ve only touched upon a few of the issues involved in this crazy matrix of variables that determine fish species populations. How about preditors and prey fish? What about water levels? Here’s a big one… “How does catch and release effect fish populations?
I’m here to tell you, the more that I know, the more confused I get!
Ned
2 Comments
What was up with the weather this summer? Fish were so scattered I didn’t even try luring the ‘eye into the boat after a couple unsuccessful evenings. Zero walleye over the opener. Zero later in June and early July…gave up.
Found a few crappie in June and some nice northerns.
This year I found a few more nice sized perch than I remember but I may have focused on them more as the smallies seemed to be smaller this year. Haven’t landed a musky yet this year but not too much energy spent on ‘em.
My question. What is happening to the walleye? Are they all getting speared? Have they quit reproducing in Tomahawk Lake?
I’ll post Ned’s reply. Interesting.
Hi Arnie,
Here’s what I know at this point. I’ll be better informed after the “Young of Year” survey comes out in late fall. Walleyes are still reproducing naturally in the lake, but the stocking program, which has been done every other year has contained fewer and smaller fry. The DNR will be stocking again next year, and is considering larger Walleye fry, and I hope to be able to tell you that there will be more of them stocked as well. One thing that I did not know was that the major preditor for Walleye minnows are Cisco. These are the very same fish which walleye eat as their main forage fish when they get big enough. Our Cisco population is healthy, and a high percentage of what the biologists call Walleye larve are preyed upon by Cisco. This is the reason that The DNR is considering using larger Walleyes to stock with. If the Walleye minnows are too large for the Cisco to eat, more Walleyes will survive to adulthood. The question will be of coarse, how many will they give us? Again, we will know a lot more about the state of our Walleye population after the release of the data from the YOY survey this fall.
Ned