Skinny bluegill and bass

[Wade Jones]

Hey everyone hope you all are great fishing season and enjoying the summer, unfortunately at my pond the fish are not doing all that great this summer. My pond has always produced 4 to 5 pound bass as well as a good population of 9-10 inch fat bluegills but, this summer is a different story. The biggest bass that i have been catching are 15-16 inchers and are pretty dang skinny, and the bluegill seem to be skinnier in the shoulders as well. We have always been on top of taking out fish regularly so i am not sure if overpopulation is the problem. Any ideas or suggestions would be great! Thanks

[Walt Foreman]

Are there any other species in the pond?  Do you feed?  How many fish of each species do you keep per year?  Is there weedgrowth in the pond?  

[Wade Jones]

yes, there are black crappie and a small amount of channel cats, there are also carp which we have been trying to eliminate for years but have been unsuccessful. We have not been keeping exact count on the number of fish that have been coming out but we usually keep 15 fish(mostly bluegill) every 1-2 weeks. Any bluegill, bass, and channel that looks skinny and unhealthy we throw onto the bank, because some are even to skinny to filet! We do not feed because it is simply just not in the budget. And this year we have lot of thick weed grow in the shallows, more than in recent years. By the way, this is a 6 acre pond with 25 feet of water. Also, im thinking that with the drought we are having in Illinois and the extreme heat, that high water temps and the low pond level might be effecting the fish. What do you think?

Thanks, Wade

 

[Walt Foreman]

Are they common carp or grass carp?  Grass carp will eventually die out if they're not re-stocked, but common carp are prolific spawners and can decimate a food chain.  If you have common carp in the pond, they can be a big problem.  You could try stocking some flathead catfish in the 5-10 lb. range, if you can source them (I could get you some if you were in this area), and if a lot of the carp are under 14" the flatheads might eventually thin them out - this approach has been used successfully by a couple state DNRs in the past - but if there are a lot of large carp, you'll have a hard time getting ahead of them.  What kind of carp are they and how numerous are they?

Is your goal for the pond big bass or big bluegill?  It's nearly impossible to have both in the same pond, as the ideal conditions for one are the worst for the other and vice versa.  If you're after big bluegill, you may be keeping too many per year out of that size pond, especially if you're keeping the larger ones.  It takes a few years in your neck of the woods for a bluegill to reach 8", so if you regularly take out the larger ones, over time you can remove all of them (the big ones) and the remaining fish never have a chance to get big before being caught out.  And, a study done in 2001 by Illinois fisheries biologists found that removing large male bluegill from a population can permanently damage the genetics of the entire population.  The right amount of harvest is good, and can make a big difference in how big your bluegill (or any species) ultimately get; but if you overdo it, you can kill the genetics of the population.  

It sounds like you may have simply harvested too many of the bigger bluegill.  Keep the intermediate ones - 7" and under - and release any bluegill over 7".  If bluegill are your main focus, releasing all bass that you catch will help greatly, as the small bass will become more numerous and will keep the smaller bluegill thinned out so that the fish that survive have more food and get much larger.

The extra weedgrowth makes it more difficult for the bass to prey on small bluegill, which not only can give the bass less food, but can also result in more small bluegill, which compete with the larger bluegill for food.  Weedgrowth should be kept to a minimum if the goal is big bluegill.  

Lower water means less carrying capacity for the pond - less total food in the food chain, resulting in more competition and slowed growth.  

[Wade Jones]

They are common carp and they have been in the pond since the pond was made which was over 40 years ago. When the carp were going crazy spawning this spring all we saw were 6 or so large carp thrashing around in the shallows and this was the only commotion we could see around the pond. This leads me to believe that there may not be too many carp in the pond. Large numbers of carp are known to create turbid waters, and almost always the water is fairly clear to very clear. How about tiger musky for the carp?

My pond has always been known to produce large bluegill (9-10 inchers). We always let go the larger ones and we are careful about not taking those big bulls. We keep only the bluegill under 8 inches. Because we ultimately want a big bluegill pond. It isnt like the 8 to 9 inchers are gone, but instead they are just very skinny, this makes me think that we simply have to many mouths and not enough food. And one more thing, we have been noticing these little leeches in the mouths of our bluegill and bass, could this be a problem? Or could these fish be diseased?

 

[Walt Foreman]

The creatures in the fishes' mouths could be some kind of parasite, which would not have a positive effect on the fish.  I would suggest contacting a state fisheries biologist to come out and look at whatever critters are in their mouths.  Hopefully he can identify what you have, and give recommendations as to remedies.  

If big bluegill are your focus, don't keep any bass, at all.  

Common carp are bad, bad.  If you have a few you likely have a bunch.  You might think about having someone electroshock the pond just to see how many carp are in there because if there are significant numbers of them they'll take a lot of food away from your bluegill.  Tiger muskie would definitely eat them, if the carp are small enough, but you probably won't be able to source muskie larger than 14" or so, and a 14" muskie is about as big around as a very thin cigar - it would be at least a couple years before the muskie would get big enough to eat any carp more than six or eight inches long.  Whereas flathead, or blue, catfish, if you got them five pounds or larger, would be able right away to eat a one-pound carp.  

Whatever parasite is in the fish's mouth could easily be part of the problem.  Do you have a lot of snails in the pond?  If you do, stocking the largest redear you can find (so they have less chance of getting eaten) will cut down on the snails.  Snails are a host for some species of parasite.

[Mike Cross]

If water quality has remained the same, then feed is an issue. Fatheads and feed could help a lot. As you probably already know if you feed the bluegill the bass will be just fine unless all the bluegill are very large.

 You said both LMB and BG were skinny,so feed/forage has to be the issue if water quality and temps are about the same as the previous years IMHO.

  Shell crackers may help take care of the parasites. I have heard Tilapia help too, by eating some of the poop and stuff like that, but should be a question for you county extention agent or local college freshwater biologist if you are that lucky.