just don't move much
Montana Fish, Wildlife and Parks
Why hasn't my adopted fish moved yet? That's a common question from students keeping track of radio-tagged fish in Missouri River Adopt-A-Fish.
And, frankly, when I hear it I'm always nervous at first. We killed it! I worry. The surgery putting in the transmitter was too much for the poor fish.
But more often than not, these fish are just not active yet. They're just sitting tight in some spot in the river they really like.
This is similar to us in the winter, when we are content to stay at home where we are comfortable. That can be especially true of these fish, since these critters are cold blooded, meaning their body temperature is the same as their surroundings.
We have had fish remain in the same spot for several months. Then, as water temperatures started to warm up, so did they, and they began to move around. These fish could be in search of food, heading to an area near a warm tributary like the Milk River or the Yellowstone River, or they might have a long journey ahead of them and want to get an early start to find an area suitable for spawning.
On occasion, these stationary "fish" could actually be a shed transmitter or perhaps a fish that didn't make it through the winter. None of us went to medical school, yet we are performing surgeries. Amazingly enough, our tag retention rate is about 90-95 percent.
I mention tag retention instead of survival because there are a few ways a fish could lose their tag without dying. First, possibly our surgeons didn't do a very good job at closing the incision and the tag might have fallen out. Secondly, some fish species also have the ability for the intestine to encapsulate the transmitter and release it with its waste - that's called trans-intestinal expulsion. Finally, sturgeon release their eggs into their body cavity when they are ripe and the tag may be passed during spawning. This could be a potential problem with female pallid sturgeon.
With that being said, I think we have been pretty successful in minor surgeries. So if we happen to be boating by and you have a fish hook stuck in you somewhere, flag us down and you can be assured we'll be able to take care of you ... well, 90-95 percent of you, anyway.
Last week, temperatures were down and weekly movement winners weren't quite as impressive as last week's 85-mile swimmers. The mover of the week was, once again, shovelnose No. 3 - Walt, Norman, or Nosy Nic - which moved 57 miles down the Missouri and one mile up the Yellowstone. Honorable mention goes to pallid No. 3 - Bubba or Hawkings - which swam 44½ miles up the Missouri River.