Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations Can fed bass return to normal foraging ?

In years past the bass in my pond (1/2 acre) have always kept the BG and LMB fry trimmed down. Last winter I noticed an otter in the pond (who mysteriously disappeared the next day). I have no idea how long he had been in there. I have noticed the normal 15-20 twelve inch bass I had have been reduced to one and two little guys of about 6" except for a group of 6 bass (2-4 lbs) I have been feeding in the same spot for 2 years now.

So the problem is I have numerous large schools of small BG and LMB (1.5"- 3") swimming around that no one is eating ! The large bass I feed just swim in and out of one of these schools of fish and seem not interested one bit in consuming any of them.

So I am assuming my smaller bass used to keep the forage trimmed down and they disappeared due to the otter. Unless something starts consuming these fish I am going to have an unwanted population explosion. If I stop feeding the larger bass I have been feeding - will they start eating these schools of small fish ?

General thinking is that when pond fish are on a feed program, they still eat other natural food items.

Depending on availability of natural food/forage, a larger fish won't go after something very small unless there's no larger natural food/forage available. There some innate tendency for a predator fish to try and optimize it's energy expenditure to get the most bang for the buck, food wise.

I'm not sure we know this exactly (nothing in ponds is exact), but if you stop feeding for a while, we think that the predator fish will end up consuming more natural food/forage.

I wish I was closer Pons star, this is where a few Saugeye would fit and do the work for you.

Unfortunately our fish and wildlife (ODFW) would never allow that. They are very adverse to any kind of introduction of non native species. I can't even get a permit for channel cats. To get the Grass Carp I have they had to be chipped, certified sterile by the Feds, and could only come from a hatchery in Arkansas.

oh great, please don't say that too loudly or pretty soon all the fish haulers will have to put microchips in all the fish before they get stocked in our ponds...

I have frequently wondered the same thing. Would lean towards Sunil's comment on abstaining from feed. It may help to train them with crippled BG caught in traps until they are off and running.

I have 30 LMB I moved indoors about july first last summer. These fish have survived and grown very well on nothing but pellets. A few weeks ago I was sorting out some minnows and found a few GSF about 1.5"-2", for grins I chucked them into that tank and 11 GSF disappeared in about 3 secs if that long.
You would have to breed that instinctive behavior completely out-if even possible- for them not to eat natural foods. I don't know of any research on that-never had a reason to look for it, but these fish have had nothing but pellets for 13 months yet instinctively attacked and ate those 11 GSF.
Just my experience.
EDIT: These were 3" fish when tanked, about a pound now.

Snipe,

That is an encouraging anecdote. I would just say that the pond situation is different in some respects. First the prey is accustomed to predation in the pond and are better able to evade predators. In a vat or aquaria, a predator can easily pin prey and in your case I imagine they readied themselves for a feeding as you approached and were moving towards the GSF even as they were falling to get to them first as they hit the water. For me, the question isn't whether fed fish will feed on natural foods. I think that is a given. What I have always wondered is whether the length of time LMB fed exclusively on feed leads to impairment as predators relative to LMB exclusively raised on forage. This question has come up before and I recall Eric mentioning that tests have resulted in both null results and also with results that suggest impairment. IIRC, he suggested it was worthwhile for aged fish to try to purchase fish that were exposed to prey in addition to the feeding. It would be great however if feeding made no difference or if its effects, if any, wore off within a short time span.

PondStar,

Just to reemphasize curtailment of feeding. There is a limit to how much a fish will feed. Just like us, they get satiated and aren't inclined to eat more when this happens. Curtailment of feeding could help you in two major ways. It would force the LMB get their needed rations from the crop of BG YOY and it may take the gas pedal off of the BG spawning.

So I have stopped feeding as of 3 days ago - kind of feeling guilty since these large bass are almost like family (did I really say that ?) - guess I will just have to wait and see what happens.

I started feeding them because they were seriously underweight for their length. Very hard in a 1/2 acre pond to keep adequate forage level up in a State that does not allow the use or sale of any type of minnows. I supplement with crawfish and mosquito fish (they are tiny) - but have no other options.

I seined my creek several times last summer when the water level got very low. I was amazed at the size range of the Gambusia. I believe they are Gambusia affinis (western Mosquitofish), the same as yours.

It appears that they can get much bigger and fatter in the riffles of the creek when the water level is too low for the LMB and GSF to reach them.

Could you create a little forage pond at a higher elevation than your main pond? If so, you could legally grow out your Gambusia, and flush them into the main pond when you have several hundred thousand in the top size class.

That won't feed your big bass, but it could help your little bass move up the weight chart!

I do have two small ponds where I raise the Gambusia. Usually put a couple thousand in the main pond every year over a 3 month period in the summer - but they all get eaten pretty quickly by the smaller bass (before the otter got them) and the "mini bass" that show up for a meal. Amazing to see little bass trying to eat the Gambusia that are almost as big as they are.

For some reason this year, neither pond has produced the number of Gambusia as they have in the past - but with the large number of bass/bluegill fry in the pond this year, I have not worried much about it.

I missed that your main pond had BG. THAT will certainly keep your bass fat and happy!