Thread: Problem Species: the Common Carp and Sunfish

So, basically, I'm from Minnesota. Our lakes tend to be eutrophic, with some glacial lakes being mesotrophic or oligotrophic. I love fishing, and along with that, I absolutely love carp fishing. They put up an amazing fight, are very easy to catch, and the bait (canned corn) is dirt cheap.

As far as I understand, carp are harmful to our waters. They dig up plants, lower the visibility of the water, and heavily out-compete native species. As far as I know, MN DNR attempts to lower or even extirpate carp populations in MN lakes have only been successful, leading to many great benefits. As far as I'd heard, the carp digging up the native plants helps Eurasion Watermilfoil, an invasive plant, take over.

So what I have to ask is whether or not I should throw carp back. I rarely eat them, though I have before, and I rarely throw them back. At the moment, whenever I catch one, I take it home, cut it up, and bury it in the garden as fertilizer.

I don't want to throw the carp back if they're really bad for the lake, and it's nice to get really good fertilizer for the garden. And, we do grow food in the garden, so it's not wasting the fertile soil.

Does anyone find this unacceptable? Catching carp and then using them just as fertilizer? Are carp really that bad for a lake?


Similarly, I also have thought of doing this with small sunfish in lakes that have been overtaken by pint-sized sunfish. Is that even legal in MN law? If so, would reducing the population of the stunted sunfish in the lake be good for the sunfish population? Does anyone find this unacceptable?

Please and thank you for answers, information, and opinions.

There's a whole industry in Australia making a bit of money by getting carp out of the Murray system.

Liquid Fertilisers - Liquid Fish Fertilisers | Charlie Carp Fertiliser

I use it on my garden with glee.

Originally Posted by adelady

There's a whole industry in Australia making a bit of money by getting carp out of the Murray system.

Liquid Fertilisers - Liquid Fish Fertilisers | Charlie Carp Fertiliser

I use it on my garden with glee.

I do know of businesses making money out of it, and major props to a majorly beneficial Aussie company.

What I'm wondering about is whether or not people think it's acceptable (most people who don't know ecology get extremely upset over it,) whether carp are actually that bad in the waters where I live (most notably, I catch my carp out of Lake Harriet, and extremely deep like that's borderline eutrophic, if not already there. The lake has a horrible milfoil infestation, and few bottom feeders other than bullheads,) and whether or not it's acceptable or beneficial to do it with very small sunfish in overpopulated lakes (sunfish whose growth was stunted because of overabundance,) while adhering to the catch limit. I'm also wondering whether or not it's legal. Lol

most people who don't know ecology get extremely upset over it

Yeah. Siiiigh. Skeptic has a few stories about people in NZ getting upset about eradication programs for various feral/invasive critters.

I think this is one area where information, lots of it, repeatedly, about the fact that some creatures are unsuited to the environment they've managed to infest. Along with information, lots of it, repeatedly, about the benefits of removing them. Cleaner, clearer water, promotion of native fish and plants, reduction of associated pests - and again and again.

Calling them 'rats of the river' or 'lake litterers' or some other vivid analogy might get the idea across.

Originally Posted by adelady

most people who don't know ecology get extremely upset over it

Yeah. Siiiigh. Skeptic has a few stories about people in NZ getting upset about eradication programs for various feral/invasive critters.

I think this is one area where information, lots of it, repeatedly, about the fact that some creatures are unsuited to the environment they've managed to infest. Along with information, lots of it, repeatedly, about the benefits of removing them. Cleaner, clearer water, promotion of native fish and plants, reduction of associated pests - and again and again.

Calling them 'rats of the river' or 'lake litterers' or some other vivid analogy might get the idea across.

People often times think you're condescending when you do that. It might be better to compare them to, say, large locust infestations.