Missing Receiver – Paddlefish/Sturgeon Project

Hey Everyone,

This is a long shot, but we are trying to locate one of the receivers we use to track our tagged Paddlefish and Lake Sturgeon in the Mississippi River. We use a different system during the summer, but to prevent ice damage we sink cages attached to buckets of concrete that we can snag from the bottom later (see picture). There is a radio tag in the white tube, and what is missing in the picture is a black cylinder about 3-4″ in diameter and ~14 inches long with a cone on one end that is hoseclamped to the center piece of rebar in the cage. This records acoustic “pings” that each of our tagged fish emits every 3 minutes. By tracking movements of these fish we are better able to assess habitat use and focus further study on spawning behavior/locations in the river system.

The receiver we are missing was located just downstream of the LaCupolis Resort on the Wisconsin side of the navigation channel. If you or anyone you know has snagged something like this with an anchor or hauled it to shore somewhere please contact me so we can recover the data contained in the receiver. Even a rough idea of a new location will allow us to use the radio tag to track the cage.

The receiver was deployed in late November before ice up, and we would like to get it out of the system before it becomes a snagging obstacle for trollers.

Thanks,

Nick Schlesser
Large Lake Specialist (Lake Pepin/Pool 4)
1801 S Oak St
Lake City, MN 55041
651-345-3365 ext 235
[email protected]

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I hope you find it. I’m very interested in learning more about the bottom dwellers. Good luck!

Missed this post. Thanks for bringing it up Gregg!

did anyone ever locate the missing receiver?

Curious as well…

Well that sucks. Did you lose a whole season of information?

Not yet.

Where we initially placed it was near the edge of the deep hole at the foot of the lake so that it could still detect Paddlefish and Lake Sturgeon that might be using that hole to overwinter. What we think happened is that either natural erosion of the edge of that hole, erosion of the edge caused by propwash from a tow, or getting dragged over the edge by an anchor may have caused the receiver and its anchor to tumble down into the deep hole.

We have attempted to snag the 50′ cable using grappling hooks dragged on the bottom and think we may have spotted it once using side scan sonar, but so far have had no luck.

Unfortunately, the radio tag we attached to the cage to help relocate it in the event this happened is very difficult to hear in the high conductivity water of the river. In testing in fact when trying to find the cage. We determined that the radio tag could only transmit through 15-20 feet of water.

I appreciate the interest folks have, and if anyone stumbles into one of our cages near the foot of the lake we would certainly appreciate a heads up.

Thanks again,

Nick

I agree Tuma that it is unfortunate. We download our receivers numerous times each year to try and minimize data loss due to receiver loss, damage, or malfunction. All of those pitfalls are possible outcomes when deploying scientific equipment, particularly on a large river system.

Our other 4 receivers we deployed over that winter recorded hundreds of thousands of data points however giving us some new perspective on the behavior of Paddlefish and Lake Sturgeon during the winter months in Pool 4.

We redeployed receivers in all those locations again this past winter, and I actually am hoping to go out today and recover some data before those receivers experience high water this spring with its associated hazards.

Thanks again,

Nick

Maybe we could get a summary of what this tracking system is telling us at some point?

No problem Brian. The long and short of it is they move a lot, and all over the lake and upper Pool 4. Movement in the lower Pool is rarer though both species use the Chippewa, and some individuals of both species have made multiple trips to the Croix.

I will try to piece together some sort of summary in my spare time that I can post, but the amount of information is fairly overwhelming to convey verbally or in print. We are working in our office to develop an electronic system to facilitate easier visualization of movement over time, but that is taking time.

Thanks for the interest,

Nick

Is there anything we can do to help other than keeping an eye out for the receiver?