Fish entrails. Beer cans. Cigarette butts.
Propane tanks. A trailer hitch.
Plastic bags full of human excrement.
These are just some of the discarded items conservation officers have found this year on frozen Minnesota lakes.
The Minnesota Department of Natural Resources says trash left behind by anglers is an old problem that seems to be growing, along with the popularity and ease of ice fishing.
"Frankly, it's been going on since we started using ice houses in Minnesota," said Lt. Mike Martin, district supervisor for the DNR's enforcement division in St. Cloud. "It's not a new phenomenon."
However, with the advent of wheeled houses and portable fish shacks that anglers can pull onto the ice with a sled, ice fishing has become more accessible in recent decades, Martin said. And more anglers means more litter.
"It's pretty amazing some of the stuff that we find on the lakes," Martin said.
That includes animal carcasses, part of a trailer hitch and the tailgate of a pickup truck, Martin said, along with the usual soda and Gatorade bottles. Sometimes the bottles are full of human urine, he said.
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Martin isn't sure why some people think it's OK to leave litter on the ice, but he has some theories.
One is a lack of accountability. When people are in a remote area without others around, they may feel free to act however they wish, he said.
"Unfortunately, I think many people are not real conscientious of what they're doing to the environment, and they're looking out for themselves," Martin said. "It's easier to leave it on the ice than it is to pick it up and take it home."
All that garbage left behind does have an impact on the environment. If it's not removed before the ice melts, it ends up in the lake or river, where it can pollute the water and harm aquatic life.
The irony is the most litter is left in the best fishing spots, Martin said.
"If it sinks directly to the bottom, that can affect the spawning areas," he said. "That can affect the aquatic growth in those spots, and impact fishing in the future."
Often, the task of picking up trash on the ice falls to well-meaning citizens or conservation officers. But Martin said it's really not his officers' job, any more than it's a state trooper's job to pick up trash along the highways.
There's another reason not to leave garbage on the ice: It's against Minnesota law. Littering, whether on public highways or public waters, is a petty misdemeanor and could earn you a $100 fine.