Jacob Thompson with his impressive 152.2-pound, 80-inch, F4 female speared on the Upriver Lakes.

Feb. 15, 2025 Harvest Update

Happy Friday to all who took to the ice. We are seven days into the season and with the impending winter storm coming in tomorrow, we saw an increase in the amount harvest today. In total, there were 65 lake sturgeon harvested with 12 juvenile females, 18 adult females and 35 males across the Winnebago System.

Lake Winnebago saw a good amount of harvest compared to the last few days. There were 41 fish harvested with 9 juvenile females, 15 adult females and 17 males. Another three fish over 100 pounds were speared, bringing the total to 27 for the season. 

Steady harvest on the Upriver Lakes brought today's total to 24 lake sturgeon (18 males, 3 adult females and 3 juvenile females). We are now at 75% of the male harvest caps on the Upriver lakes (33 juvenile females, 38 adult females and 178 males total for the Upriver Lakes season).

The largest fish of the day also came from the Upriver lakes. Jacob Thompson speared a 152.2-pound, 80-inch, F4 female.     

View the full details in today's harvest report.

Here on this Valentine’s Day, many of us are thinking about our partners or thinking about what we are looking for in a partner. And while many people look at the sturgeon and don’t see something cute or attractive, all attributes of the sturgeon play a specific purpose in their survival. The whiskers on the bottom of their head are called barbels. These are sensory organs to help them find food. Once they locate a source of food, they use their long tube-like mouth to suction or vacuum up the prey items. These attributes, while might be strange to the human eye, are all necessary to help this species survive and thrive in the Winnebago system. 

For those spearers taking to the ice tomorrow, please remember that Battle on Bago will still be occurring. Further, with the cold weather and snow coming in tonight, please be careful and follow all ice safety best practices over the rest of the weekend.

Please note, due to water clarity, the Pipe registration station will still be closed tomorrow. For those registering fish in that area, the Quinney registration station is the next closest station. Please make sure to adjust accordingly. Thank you, and congrats to all our spearers.

Estimating ages of sturgeon is similar to aging trees – you simply count the rings. The only difference is that for lake sturgeon, you could be counting 80 to 100 rings on something the size of a quarter. / Photo Credits: iStock/t_kimura (left) and Wisconsin DNR (right)

Aging To Perfection Another spin around the sun, and we are all another year older. Why do we as humans put so much value on age? For many, it is a way to understand how we interact with this world, gaining more knowledge and experience each year. To others, such as healthcare workers, it may help measure health and health risks. Just like doctors examining people, the age and growth of a fish species can be another metric for insight into the fish population's condition. Tracking age trends also allows us to ensure fish populations are growing appropriately. However, aging fish isn't as easy as talking to a patient. Fish have calcified structures on their pectoral fins (fin rays) and ear bones (otoliths). These structures continue to grow in rings throughout their lifespan: each year, a new layer or ring forms. Sound familiar? Trees have a very similar process, putting down new growth, or rings, with each passing year. Each ring represents one year of the tree's life, giving us a quick and easy way to age a tree. Fisheries managers use these same principles to age fish. Biologists can take a slice of the fin ray or otolith and count the rings to find a fish's age. This method works well for the average fish species, which only lives about 10 or 20 years for species that tend to have longer life spans. However, because lake sturgeon live so long, counting these rings can be a challenge. Image counting the rings on a 100-year-old tree, but the tree is the width of a quarter - that's what it's like for sturgeon. At some point, those rings are too close together to try to distinguish, making the standard aging techniques rather ineffective. Due to this difficulty, sturgeon researchers are looking for better aging techniques for this incredible prehistoric species. The Wisconsin DNR is partnering with various organizations to study and better understand how to age these long-lived fish. As new techniques are created, there needs to be a way to test the method against known age values. The good news is that Sturgeon for Tomorrow and the Wisconsin DNR have been partnering on a project that allows us to do just that in the Winnebago System. About 500 lake sturgeon are PIT-tagged and stocked in the Upper Fox River each year. As sturgeon seasons pass and sturgeon grow, a few stocked fish inevitably end up being harvested. These harvested fish are then scanned for PIT tags at registration stations. If a fish has a PIT tag indicating it was a stocked fish, we can collect the fin rays and otoliths to compare those aging methods to the date they were stocked. Utilizing this data, we can verify the accuracy of any age estimates. There have been different ways researchers and biologists have tried to estimate age accurately. Currently, most biologists use age estimates based on years of data with length and/or weight. Others are working on a correction factor that can be applied to ages estimated from fin rays to get a more accurate age. Some intrepid researchers are studying whether chemical signatures in the calcified structures will unlock the key to aging sturgeon. But until then, the Winnebago System will continue to play a large role in sturgeon aging research. One day, we hope to have a clearer understanding of the exact age of individual fish without tagging them as babies. Until then, the best way to estimate the age of your harvested lake sturgeon from the Winnebago System is by using the length/age graph.

No Ice Is 100% Safe

If using UTVs on the ice, here are a few basic safety tips to remember:

• Remember UTVs are heavy. They are the heaviest recreational vehicle out on the ice, often being close to 3,000 pounds. This is similar to a car or truck.
• Have a plan in case you do go through the ice.
• Roll your window down when traveling on the ice and make sure you can easily open your door – drive slow and turn the radio down so that you can use eyes and ears to watch and hear for potential issues coming up.
• Make sure you have life jackets or some other type of floatation for every occupant of the UTV.
• Recovery for the UTV or other vehicle is the responsibility of the owner/operator. After 30 days, the owner can be fined each day after 30 days.
• Recovery rates for the machine can also be very expensive.
• This may not be the year to explore new locations – stick to known areas that typically have better ice conditions.
• Never consume alcohol or drugs before or during your ride.
• Carry a cell phone, and let people know where you are going and when you’ll return home.
• Watch for pressure ridges or ice buckling. These can be dangerous due to thin ice and open water.

Remember – the DNR does not monitor ice conditions. Local fishing clubs, outfitters and bait shops are the best sources for local current ice conditions.  

Check out the DNR’s Ice Safety webpage for more information on staying safe on the ice, including tips for creating ice claws and what to do if you fall through ice.

Additional information on the Winnebago System sturgeon spearing season can be found on the DNR website.