The Community Association Institute West Florida Chapter recently published the following article in their Community magazine that Aquatic Systems Sarasota Biologist Sarah Bowen penned for HOA and Community Board members about fish stocking for lakes.
Don’t forget one of the most important line items on your budget for next year: fish stocking for your pond! If you have wondered how fish get into ponds, you may not have realized that it can be the responsibility of the HOA or CDD to maintain healthy fisheries. Now is a good time of year to start budgeting for fish stocking, as some of the species are stocked in the winter months to avoid stress to the fish. Aquatic maintenance companies can stock a variety of fish for different purposes.
Benefits include improved fishing populations, a balanced fishery with diversity, increased recreational activity, reductions in exotic fish, reduction in unsightly vegetation, and some smaller fish can even reduce certain insect larvae. Traditionally there are three categories of fish that can be stocked: Triploid Grass Carp, Bream, and Sportfish.
Triploid Grass Carp are not native to Florida, which is why they have the funny ‘Triploid’ prefix to their name. This species is highly controlled by the Florida Fish and Wildlife Conservation Commission (FWC). Therefore, all fish stocked are Triploid. This designates that they have been sterilized and cannot reproduce in nature. Carp are stocked specifically to eat plant growth in the ponds. Some of these include Hydrilla, Musk- grass, Southern Naiad, Slender Spike rush, Duckweed, Azolla, and Slender Pondweed. These plant species can create very dense mats that provide platforms for algae to grow on. The target vegetation can also be unsightly when it reaches the surface of the water or covers the entirety of the pond. Some submersed vegetation has also been known to cause dangerous environment for watersports, can block navigation routes, restrict drainage, and decrease biodiversity. It is important to stock at the proper rate that takes into ac- count acreage and target as to not overstock. Some of the vegetation targeted is native and provides good habitat for native fish populations, so the goal is to reduce vegetation, not eradicate it completely.
While there is actually a fish called a Bream, Bream also refers to all smaller fish that may be used for stocking. Stocking smaller fish increases the population of feeder fish for larger sportfishing breeds. Bream include all smaller fish that include redear and bluegill. One reason you might stock bream is to increase the population of feeder fish to prepare for stocking sport fish later. Bass need plenty to eat to grow big, so it is important to make sure their food supply is sizable before stocking. The more common purpose for stocking bream would be to decrease certain insect larvae. One of the main targets are called midge fly larvae. Midge flies lay their eggs in the bottom on ponds, and if left unchecked, can cause nuisance sized swarms. Appropriate stocking rates will con- sider the acreage of a pond.
Catching fish is one of the top recreational activities for both native Floridians and tourists, which is why stocking of sportfish is on our list. Common sportfish in ponds include Large- mouth Bass, Bluegill Sunfish, Re- dear Sunfish, and Channel Catfish. As you might recall, both Bluegill and Redear were also found on the bream list as feeder fish, but as they grow large, are another favorite for fisherman. Other benefits for sportfish other than recreational purposes are a more balanced fishery and reduction in exotic fish species due to natural native competition for food and habitat. Common exotic fish in Florida ponds include Tilapia, Mayan Chichlid, Osca, and Bullseye Snakehead.
Exotic or invasive species, as they are also known, are non-native animals or plants that have made their way to areas outside of their normal range, to the detriment of the native species. Fish fry and mollusk larvae may travel thousands of miles aboard container ships in bilge water, released purposely or accidentally from fisheries or even from people who keep some of these creatures as pets. Tilapia, Bullseye Snakehead and Osca compete with native fish species for food and upset the ecological balance of our environment.
Now that we know what kind of fish you can stock, how do you know what kind of fish you already have? Aquatic companies can perform a fishery study to answer those questions. Start with a visual survey to assess habitat along shorelines such as vegetation, stumps, rock pilings, etc.
Next, a vegetation survey will use several samples to identify the dominate vegetation species. If pond mapping is included, you can determine vegetation biomass readings to know where the growth is the thickest. Minimal water testing is usually performed as part of the fisheries study to check for dissolved oxygen, nutrient, and turbidity levels.
To do a physical assessment of the fish present in your pond, an electro-fishing boat is used to sample data on the types and quantities of fish. This is a practice used by fisheries’ biologists all over and uses electricity pulsed through water to temporarily stun fish for a quick survey of number and species. The maximum range is about a 6-8 ft radius around the boat, so multiple sampling points on the pond are taken to get a representative sample of the fish population. After all data is collected, fisheries management recommendations can include fish stocking, fish removal, habitat enhancement, plantings, installation of feeders, or follow-up surveys.