Pond Boss Forums MANAGING AN EXISTING POND Corrective stocking Grass Carp - observations and questions

Not long ago our State (Oregon) approved the use of grass carp in private ponds. They have to be sterile and so certified by the Feds and micro chipped in case one gets out of your pond- so they know where it came from. There are also restrictions on hole sizes for screening outlets pipes. The only hatchery that meets the standards set is in Arkansas, so the cost of shipping makes this an expensive proposition.

There were little guidelines as to how many fish you should stock in a 1/2 acre pond that is 12' deep at the deepest point and probably averages 6-7' for the whole pond. I started with 5 fish 12" long - but the osprey got 3 of those the first year. I ordered 5 more and the osprey got 2 of those 5 - so now I have a total of 5 and in just a couple of years they have grown tremendously - guessing around 30" long and 15 lbs. each.

So now the problem - after years of raking 100's of pounds of weeds out of the pond every year and using Aquathol Super K - I cannot find a weed anywhere! I have even seen them pulling at the cattails and the other day I saw a piece of cattail sticking up vertically and swimming around the pond like a periscope on a submarine- I presume there was a grass carp on the other end.

So now to the question part of this post - 1) when the grass carp have nothing more to eat, will they starve to death ?? should they get supplemental feeding ?? and 2) what does the total elimination of all weeds due to the fish (bass,bluegill) as far as the weeds link to the food chain and for a hiding place for juvenile fish ?? I am concerned about both of these items, but because this is such a new thing in our State, there really isn't anyone with the knowledge to help answer these questions.

So - your thoughts ??

1) They won't starve, they're adaptable in their diet but their growth rate will stall. Grass carp will gladly take fish feed, both high and low end. I wouldn't waste my money on them...

2) A lack of vegetation can lead to a high percentage of YOY fish bring eaten before they can get size to them. This could be good or bad depending on one's goals.

You can attempt to catch them. Peas, corn, dough balls will all work, especially if they're hungry. Or you can try bow fishing for them.

I would get rid of them. When they get that big they poop too much.

Pond star if you get rid of your grass carp you will be back to raking hundreds of pounds of vegetation or using chemicals. Chemicals are expensive and who knows what they can cause. The pooping helps vegetation grow but your grass carp are so efficient that they are eating the veggies as they sprout. I fed my fish very cheap dog pellets and the grass carp ate the pellets right along with the other fish. I had a pond like yours with 18 grass carp in my one acre pond here in east central Indiana. Some will tell you that grass carp don't eat as much as they get older but I think you see they control the vegetation with the same numbers you put in just as I experienced.