Getting to go back and catch the same fish nearly 25 years later makes you appreciate those resources even more and understand that fish of legends can exist.
I get asked about one topic nearly every time I give a presentation on the fisheries around the Quad-Cities area.
There are stories of the 100-year-old sturgeon and 50-year-old catfish that haunt the local locks and dams. Recently there was a published report of 100-plus-year-old buffalo species (the fish buffalo) in the Dakotas. So how do biologists come up with these estimates?
Nearly everyone growing up learns about tree rings, and that you can age a tree from those rings. The reality is the “rings” are just the slowing of growth, making that portion of the tree look darker. That can occur in trees due to winter or other hostile conditions.
In fish or freshwater mussels, a prolonged disturbance can slow "growth rings" for a variety of reasons. Most often, fish are aged by their ear bones, called otoliths, or from their scales. In the case of catfish, which do not have scales, the knuckle on the pectoral fin is sometimes taken to slice and age. Unfortunately, most bone sectioning is lethal to the fish. All of these techniques are good, but not always perfect. However, I would like to report the age of a big catfish of which I can confirm a minimum age.
Back in the late 1990s I was a graduate student at Western Illinois University, majoring in fisheries management, and was able to work with Rob Hilsabeck, a fairly new Illinois DNR district fish biologist, on Canton Lake near Peoria, which was overrun with common carp. It was decided to introduce flathead catfish to see if they could thin the carp and improve the water clarity for drinking water purposes.
Fish were purchased from a commercial fisherman on the Illinois River, with 200 or so receiving a PIT tag, or passive integrated transponder tag. In the late 1990s, this was new technology. Today, most pets have one placed between their shoulder blades as a way to identify the animal. These tags are about the size of a grain of rice, are inserted under the skin and last a long, long time.
Fast forward to 2021 and those two guys I mentioned earlier now have grey hair. Being able to go back to a lake nearly 25 years later to search for any remaining tagged fish is quite the treat. One can only hope to validate that some fish could survive that long to bring some bit of truth to these great fables.
I am happy to report that we were able to catch one of those elusive tags this week, number 4138756536, which was originally tagged and stocked on Sept 10, 1998. It was 25 inches long and weighed just under 7 pounds at the time of its release. Today, it is 44 inches long and weighs 40 pounds. A fish of that size was a minimum of five years old at 25 inches, but it could have been a few years older yet. Therefore, when tacking on the 23 years it had been roaming the lake, it is easy to confirm that there is at least a 28-year-old flathead catfish in that lake, which I have held twice in my lifetime.
We did catch bigger fish, some exceeding 50 pounds, which likely were from the original stockings, too. But we only tagged about 25% of them at that time.
All of the fish were returned to the lake so I may attempt to catch them again in … well … how about 2046. Then, hopefully, I can confirm that there are 50-year-old monster catfish in our lakes and rivers and maybe see some old fish friends in the process.
World Outdoors columnist Jeremiah Haas can be reached at nukefishguy@gmail.com
May 19, 2021 at 09:09AM
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WORLD OUTDOORS: How old is that fish? - Quad-Cities Online
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