Pond Boss Forums STOCKING A NEW POND Raising Forage and Bait Yankee Newb with a Question on Crayfish

I've had my pond for about ten years. It's lined and has a water source coming in from a small spring. Size is approx. 30' x 60' and triangular. Depth is 7.5' at it's deepest with mostly steep sides. There is no water outlet. The overflow goes out in the field and disappears down the gopher holes without making more than 300 feet. I aerate with an air pump and 8" stone at night so as to keep water temperatures at its lowest. Last fall I planted 150 4" rainbow trout and put them on an automatic game feeder that spews forth about a pound of Aquamax 500 twice a day. Last year I was inundated with curly leaf pond weed such that it was almost a mat. I went ahead and drained the pond and pressure-washed it down to the liner - no more mud, no more plants - and smoked all 63 of the remaining 3 to 3.5 pound fish.

Last September I planted another 150 4" rainbow. They're now running in the 14" to 15" range,. I'm fishing them about every other day to get the numbers down. I plan to carry a bunch over this year instead of pulling them all. I just hope they'll make it through July and August without succumbing to excessive heat. I may have to put the air on 24-hours per day to carry them through the hot months.

I have access to lots of crawdads in a couple of the small local lakes. I don't yet know their size, but the fishing regs say I can only keep those over 3.5" from nose to tail. According to Washington State Dept. of Fish and Wildlife there is one native species and at least two invasive species. If I catch them in the wild I have to immediately kill the invaders.

I would like to plant my little pond with some crawdads. Obviously I want them to be compatible with the trout. A couple of questions:

1). Do I have to have any structure in the pond?

2). Should I wait until I have more bottom sediment (like next year) before I put the critters in there?

3). What happens when they molt and I have 3 or 4 pound trout in there? Last year the big ones were 3.5 to 3.75 pounds by the end of July.

4). Is this a foolish idea and should I just catch the local mudbugs and have them for dinner?

Thanks for your response.

What is your reasoning for wanting crayfish in your pond?

Seems to me the risks involved far outweigh any benefits...

Oh yeah, and welcome to Pond Boss! Sounds like you have a neat set up. I am not sure running the air stone 24 hours a day during the heat of summer will help, if anything it may be detrimental. Night time running is probably best.

I expect the trout will eat the crawdads.

But then, I don't know that much about trout.

I like the idea of a second crop that may help to keep some of the uneaten fish food reduced. I had tried blue cats in the past, but they didn't grow worth a damn. I think the floating food never made it to the botoom and they couln't compete with the trout. Truthfully, I hope the environment would be sufficient to harvest for a few good meals in the fall and spring. Gumbo is a good thing. And it's easier than going down to the river or the lakes to fill that pot.

To what risks do you refer? Risks to the crawdads or to the trout by eating any eggs from their spawning (though I haven't had the trout in there long enough to see them carrying eggs, but I think I might later this year). My other guess is that the crawdads are an attractant to heron and 'coons. The good part is that I have pretty steep sides all around - no place for even the heron to really get a good place from which to fish (besides, "Herbie" prefers the resident gopher population for fine dining). The local osprey is bad enough. I think he (or she) got about 40 of The Kids last year (I haven't seen him yet this spring, but he may be sneakier than I give him credit for).

I haven't looked into factors that affect DO to any extent. I just know that warm water and decaying fish food and plant detritus is a bad thing and that air is a good thing. Last year I ran the air 24 hours a day and was always worried I would see a bunch of floaters every time I went to the pond. I assumed the fact that they quit biting when it got warm was the result of low DO. The change to night time air this year is an attempt to keep temps as low as possible by reducing water circulation during the heat of the day. I will be looking for a table or chart relating water temp to DO as I cannot measure DO directly (no instrumentation). I also will have questions as to the size and number of fish I can sustain in relation to DO levels, temperature, and to roughly 5,000 cubic feet of pond volume.

Thanks for the welcome. I just found this site yesterday and am impressed with the scope and expertise. I have also taken advantage of internet forums dedicated to my Triumph motorcycle, old Benz CLK, Dodge pickup, and '57 MG. All three have been truly valuable in maintaining those cars over the last few years. I look forward to participating in this arena.

FWIW. I currently have RBT in my pond. The feed sinks, both AM 500 & 600. Not a lot, but some does. My water is clear enough to see this. I also have a few CC. The feeder goes off, and the trout are savages, however some of the feed drifts towards shore, so does the feeding trout following it. Following right behind them on the pond's bottom is the CC cleaning up the sunken pellets. They get along beautifully. I have never seen one of my trout take a pellet sinking. I see them passing those up all the time. This isn't the case for everybody.

If the blue catfish didn't make it because of no extra pellets, why do you think there will be pellets for the crayfish?

There could be a couple of factors at work:

1). The Trout are Overstocked. 150 2-pounders are pretty damned aggressive when it comes to feeding such that there is a significant population of smaller (8" to 10") fish in with the more aggressive 14" to 15" piggys. I don't see any floating feed between feeding the twice-a-day feedings even though the wind blows here in the Columbia Gorge all summer long.

2). The Trout are Underfed. I have maxed out the operation time on the feeder since the end of February (about 16 seconds of spewage). That spews a little less than a pound. At this point there is no excess I can see - floating or otherwise. On the other hand, my water is likely not as crystal as yours.

3). Too Many Cats. Last time I started with 100 4" fingerlings. They just didn't seem to grow. My guess is that there were just too many and I should cut the number down to about fifteen.

4). Cold Water. I was also told that the six or seven months of colder weather made the cats less active and they cut way down on feeding activity - hence minimal growth.

I may try and plant a few more blue cats later this year. Even though they may be able to feed on sunken food I also have native shrimp in the pond. I caught a trout the other day and, as I was taking out the hook, one about half-an-inch long crawled out of his mouth. I also saw them in the mud when I cleaned the pond out last year. I left some of that mud to have a little breeding stock this year.

As far as the crawdads are concerned, I really don't even know if they're carnivores, herbivores, or omnivores. I'm still trying to get more information on what they'd need and what benefit (other than proper gumbo) it might have to the pond - like if they eat algae.

Thanks for the responses, guys

Crayfish do eat plants, living and some forms or fresh dead plants including algae - scavengers. They will also eat invertebrates and meat of various forms. They do eat dying and dead fish and uneaten fish food. Most of them are pretty omnivorous, some more herbivorous, and some eat more meat than other species. I think the crays will need quite a bit of cover as refuge from trout and catfish. If trout don't eat the crays the catfish will relish them and probably eat all of them unless you have proper cover. If trout are eating shrimp I suspect they will also eat crayfish. Best cover for crays to my knowledge is lots of rock cobble for crays to hide among the crevices and under the rock pieces.

Too many trout does require extra food if one wants growth. It basically amounts to how many mouths need fed.

Aeration 24/7 will tend to make the bottom water as warm as the surface water possibly bad for trout even if you have lots of DO, heat will kill them and so will lack of DO.

gorgerider, even if you don't have a way to measure DO, get a thermometer and measure water temp.

Here's my experience with trout in a pond.

One year I ran the bottom diffuser during the night, just when temps were below 70°F. The trout went belly up relatively quickly because the bottom diffuser did it's job, mixing the upper warm and lower cool water so it was all the same temp. The upper water warmed up more than the lower water cooled, and all the trout were gone by late May.

Last year I didn't run the botttom diffuser. March temps were in the 80's and May-June were in the 90's. My last trout died July 4th from a Great Blue Heron. Both years I pumped well water into the pond at 25 gpm. I think by NOT running the diffuser the trout lasted longer because they had a cold water refuge to go to. (although it might not have had enough O2 to over summer the trout)

This year I am going to try a diffuser/aeration system that I'm designing that will only aerate the lower, colder water. We'll see if it works or not.

If it works you need to sell the plans Scott!

If it works I think I can sell a put-it-together yourself kit.