At Inspired by Nature, Inc., we are always getting questions about fish management and stocking. As you may know, our answer is usually in the form of another question, “What are your goals for the pond?” As you decide what types of fish you may want to stock, here are a few pointers.
First, my most often asked question… “How many more grass carp should I add to my pond? I just can’t get them to control the stringy mat algae on the surface.” Actually, you can add about as many as you want, they still will not control the filamentous mat algae. Grass carp are selective eaters, first consuming desirable rooted vegetation prior to even considering the consumption of algae. In fact, they’ll beach themselves on the side of your pond to grab a bite of lawn long before they’ll eat the algae. Does this make grass carp useless for pond management? Absolutely not, they can provide long-term control of rooted vegetation provided that proper numbers are stocked for the type of plant material that you have. Remember, that grass carp prefer to eat grassy material, if you do not have rooted plants in your pond, they will have nothing to eat. No food equals no fish. No fish equals wasted money! Therefore, do not stock white amur for preventative purposes. It is best to stock them as soon as you see that the vegetation is getting slightly out of control (greater than 20% of the pond area). If you’re not sure what type of plant you have, send IBN a sample and we’ll be glad to assess what needs to be done.
“Where can I get these so-called super hybrid bluegill?” Many pond owners are convinced that they need to have hybrid bluegill in their ponds. They grow fast, taste great, and they get to lunker sizes (supposedly up to 3 ¾ pounds). What could be wrong with that? Nothing, if you can prevent them from reproducing in your pond. The hybrid bluegill is a cross between a bluegill and a green sunfish. This produces a viable (NOT STERILE) cross.
Hybrid bluegill will reproduce within your pond! If you’re told differently, you’re being lied to. The catch is that their offspring will usually be about 90% male and 10% female. This will limit reproduction, but will by no means stop it. This is especially true if you have also stocked pure bred bluegill at the same time given that these should be nearer a 50:50 ratio male to female. This provides an abundance of fertile females for the 90% male blue-green sunfish population to reproduce with. Okay, so the hybrid bluegill will reproduce between themselves and with the pure bluegill in the pond. Now for the kicker. Genetics will prove to you that when hybrid bluegill reproduce, their offspring will revert back to either bluegill or green sunfish. For those of you with a pond full of green sunfish, you can contest to the problems that they cause. Nipping, stunting, and competition with largemouth bass are just a few of their traits.
Catfish have their place in many ponds, but make sure that your pond is one of them. Catfish grow fast, are easily pellet trained, and can survive about any condition you throw at them. If you’re a huge fan of catfish fillets, stock them! If you’re indifferent, I’d probably not stock them. Many people are under the belief that catfish only eat rotted bottom materials and work to keep the pond bottom clean. Would you eat the black muck at the bottom of your pond? Catfish will in fact eat dead fish and other bottom insects, crustaceans and Catfish have their place in many ponds, but make sure that your pond is one of I’ve also seen them consume the occasional duck and baby goose. One thing many people don’t consider is that catfish also eat fair amounts of bluegill during the night, creating competition with your largemouth bass. If you do decide to stock and harvest catfish, remember that catfish rarely reproduce in smaller impoundments. Therefore stock what you catch to replace those harvested.
And my favorite… common carp, golfish, and koi. During a typical season I see 20-30 ponds that are completely overrun with at least one of these three species. The common carp (Cyprinus carpio) and koi (Cyprinus carpio) are actually the same fish species, with koi being highly domesticated and bred for their ornate color. Goldfish are a separate species but with similar characteristics. These fish are highly reproductive and if only a few predators are present, will fill your pond quickly. So what’s the problem with a bunch of colorful goldfish swimming around my pond? Hungry goldfish, carp, and koi will root around in the bottom and create water clarity problems, especially if you have a clay or silt bottom. Best of all, any of these three species will gladly hybridize with each other. So, if you think you’ll add one of each to prevent them from reproducing, you’ll be sadly mistaken. A little example: I performed a fish kill on a 1/3 acre pond that had approximately six 4-inch goldfish originally stocked 4 years prior. At the time of the fish kill, the was brown, muddy, and had a clarity of 5 inches. After two days of netting dead goldfish, we had accumulated over 175 pounds of goldfish from a shallow 1/3 acre pond. Yes, 175 pounds in a small, shallow pond, all from 6 original fish! Granted, there were no predators in this system, but you can see the potential for problems that these guys possess. And finally, how do undesirable fish such as goldfish, carp, and green sunfish end up in my pond? As far as I am aware, there is still no such thing as spontaneous generation. Birds rarely transport fish or fish eggs from pond to pond. So what’s left? The neighborhood kids, fishermen’s bait buckets, and “contaminated” fish stockings. The biggest culprit, however, is the most easily prevented. Many pond owners rely on ditch or creek water to fill or maintain the water levels in their pond. In doing so, many fish, insects, snails, and leeches are pumped directly into your pond. And believe it or not, many of these fish survive the ordeal with little or no harm. My suggestion, if your going to pump water into your pond, get yourself a filter sock (IBN carries these by the way). The filter socks are a small investment to protect the health of your fishery. As you can imagine, there are no black and white rules for managing fish in your pond. The above fish recommendations can, however, make achieving the goals for you pond much easier. With our move to our spacious new location, we now have the facilities to provide a full line of fish for your pond stocking needs. If you have any questions about stocking rates or which fish species to stock, call and talk with a biologist to decide what fish will work best for your pond.