The DNR and Great Lakes Indian Fish and Wildlife Commission completed their joint annual fall electrofishing survey of the Chippewa Flowage on September 14 and 15. Sections of shoreline on both the east and west sides were surveyed with the focus being on juvenile walleye and muskellunge. The DNR crew took the west side in 2016. Unfortunately, finalized numbers for these types of surveys are typically not available until December when the two agencies meet to exchange data from the fall. However, I feel comfortable making the following statements about what we saw on our sections of the Flowage:
We have a walleye year class in 2016! And it’s a pretty good one too. We captured hundreds of ‘young of year’ (YOY) walleye that are the product of the spawning from this past spring. These small walleye were in excellent condition and were between 6 and 7.5 inches in length. Based on what we saw we expect this to come out at the strongest year class produced in the last decade. 2014 was another good year for walleye recruitment and we stocked 73,000 in 2015. With those three strong classes all being well represented in the fishery there is reason to be very optimistic about the future of walleye on the Flowage.
Musky did well in 2016 too. Musky are rare by design and detecting their recruitment through these surveys can be challenging. We found natural born muskellunge fingerlings (8-10 inches) in several parts of the Flowage in 2016. In total, the number of YOY muskellunge captured by the DNR crew during these surveys is the most seen since 1999. That’s a great sign for the future of the musky fishery.
Other fish also did pretty well. It was not just walleye and musky that enjoyed good spawning success this year. YOY northern pike were particularly abundant this year. That finding dashed hopes that pike were having a difficult time reproducing following drawdowns. Little pike are still abundant and still pose a risk for young muskellunge and walleye. We encourage anglers to harvest small pike as often as possible. Largemouth bass also reproduced very well in 2016. Unlike YOY pike (which are now 9-11 inches), YOY largemouth are still very vulnerable to predation and other sources of mortality through winter. As such, it remains to be seen if this year class of largemouth will still be abundant in 2017. Expect a report on that in the future.
Bigger stocked muskies do better. We recaptured yet another muskellunge that was stocked in 2013 with a PIT tag in its belly. Every time we capture one of these tagged fish we learn a lot. What we have learned from the 2013 musky class is that size at the time of stocking matters. Of the 7 we have recaptured from that class, 6 were over 12 inches at the time of stocking. Stocked fingerings under 12 inches, which made up a majority of what was stocked, are surviving at a much lower rate. Predation and winter mortality would be the two big factors likely driving that relationship. Getting muskellunge fingerlings over 12 inches before they were stocked has the potential to greatly improve survival.
This survey followed the third consecutive 8 foot winter drawdown. Over those years we have learned a lot about the effects that those drawdowns have on fish. When things go right, they can be a powerful tool to enhance the walleye (and maybe the musky) population. The key seems to be how things go in the spring. In the two years when we refilled quickly (2014 and 2016) we had good spawning conditions and produced a year class. When we did not fill quickly (2015) we had minimal walleye recruitment. So, while what happens early in the winter may set the stage, spring is a critical period for these drawdowns to be successful. With regards to drawdown depth, we’ve had a lot of success with 8 feet, which is more than enough to expose and recharge the walleye spawning areas. Other reservoirs like the Turtle Flambeau Flowage have walleye spawning success with drawdowns of 4-6 feet, reinforcing the concept that deeper may not always be better. We will continue to learn from these drawdowns over the coming years. By going back to a ‘normal’ drawdown timing in 2016 we will have an opportunity’ to see how the plant and fish communities respond. Fish kills will once again be a risk this winter, like every winter, and the major determinant will be how long winter stretches on.
Anglers throughout the summer reported catching a lot of ‘short’ walleye (<15 inches). While that creates some excitement about the future, it also can be a source of frustration when few legal sized fish are getting caught. This fall we will be analyzing growth rates of walleye on the Chippewa Flowage to make sure that fish are still getting to legal size in a reasonable amount of time. If we find that growth is still adequate, we'll have to be a little patient and give these young fish time to get up to size. If we find that growth has slowed, a new regulation will be considered that would allow harvest of smaller fish. Panfish
Panfish in the Flowage will become a topic of conversation in the near future. Bluegill abundance has dropped in response to the drawdowns and the increased number of small walleye. That’s actually a good thing, as it has allowed the average size of bluegill to increase by almost an inch and a half. Crappie are still a popular fixture of the fishery and have maintained an average size that could be described as ‘just good enough’, providing lots of eaters but few large fish. Yellow perch are making a comeback that seems to coincide with when the walleye started improving. Taking some of those big perch home to eat will be a powerful temptation for flowage anglers, though we would recommend resisting that urge if possible. Perch are an important forage fish for all the other species we value in the lake and the largest ones are almost always females. Overall, panfish are doing relatively well but we could see improvements in size with a more restrictive bag limit (as we had in the past). No decision has been made on that at this point, and any deliberations will involve lots of public feedback and LCFRA involvement.
By the time you read this there will have been musky fingerlings stocked into the Chippewa Flowage from the Governor Thompson Hatchery in Spooner. These fish were raised from eggs collected in the spring of 2016 on the Chip. The DNR partnered with the Hayward Lakes Chapter of Muskies Inc. who purchased additional feed for this batch of fish to allow them to be held in the hatchery longer and grown to a bigger size. As noted above, that extra inch or two makes’ a huge difference in their survival once they get into the lake. These fish are all being PIT tagged so they can be tracked in the future. The final number of stocked muskellunge is not available as of this writing.