POND AND LAKE CONDITIONS THAT
AFFECT FISH GROWTH
Fish production is affected by the fertility of the soil in the watershed, water clarity and color, aquatic plant densities and other fish species present in the pond.
Soil fertility: Agriculture crops grow better in northern Missouri than in south central Missouri. This is due to the higher soil fertility in the northern part of the state. For this reason, ponds in northern Missouri are more likely to support larger crops of fish than ponds further south.
Stocking rates are usually based on the pond/lake's ability to provide a natural food chain, which is directly related to the fertility of the soil in the drainage area. The natural food chain in a pond/lake is an important key to a successful fishery. Life in a pond is a complex, interlocked chain of plants and animals. The food supply for fish depends upon the presence of sun and available plant nutrients (organic matter and dissolved minerals). Nutrients stimulate growth of tiny aquatic green plants called phytoplankton. Phytoplankton serves as a food source for microscopic animal life called zooplankton, zooplankton then multiply and becomes food for small fish, aquatic insects and their larvae; they, in turn, are eaten by small fingerling fish, crawfish and other larger aquatic animals. Small fish, crayfish and insects are eaten by larger fish. Then we eat the larger fish! Thus, the food chain is completed with
continuous links extending from basic nutrients found in the soil to adult fish and on to us.
Care of the Watershed: The land that drains into a pond/lake is its watershed. The ideal watershed ratio is 10 to 15 acres of land for every 1 acre of pond. A pond/lake owner should strive to keep the watershed in grasses and trees. If this is not possible, maintain at least a 100 foot wide buffer strip of grass in the drainage area and around the pond/lake. Grass catches sediment before it enters the water and absorbs excess nutrients, such as nitrogen and phosphorus, that may wash off fields, pastures or lawns. Although fish need nutrients to grow, too many may cause aquatic plant and algae problems.
Water clarity and color: Water clarity (clearness) in a pond/lake is very important because sight-feeding fish must be able to see what they intend to eat. Water clarity of 2 to 4 feet is ideal. Extremely clear ponds/lakes lack the fertility needed for good fish growth.
Pond/lake water with a slight greenish tint usually produces more fish. The green color is caused by the presence of suspended phytoplankton concentrations called blooms.
Suspended soil sediments washed into ponds/lakes after heavy rains will change the color of the water, leaving it muddy looking Color should return to normal within a few days as settling occurs. Unfortunately some pond/lakes never clear. As a rule of thumb, if the pond/lake is muddy enough that a light colored object, lowered at least 2 to 3 feet under the water, can not be seen, and this condition is present most of year, the chances of growing large sight-feeding fish is greatly reduced.
Heavy sediment loads make if difficult for sight-feeding fish to locate food and can stress fish by irritating their gills. Chronically muddy pond/lakes restrict light penetration, which limits photosynthesis (production of oxygen), thereby reducing overall pond productivity. In pond/lakes where clarity is about 18 inches, the answer may be to leave the pond/lake untreated and stock with channel catfish which do not depend on sight to obtain their food. Because natural food production will be minimal in such an environment, it would be advisable to feed the catfish a commercial fish food.
To have a good, well balanced fish population in a pond/lake the muddy water problem will have to be taken care of. The first step in reducing suspended soil particles in the water is to locate the source of the problem; soil erosion from bare soil or wave action in shallow water may be the cause. A 50 - 100 foot wide grass strip around the pond/lake could be the solution. Livestock watering in the pond/lake and keeping soil particles suspended could also cause a problem and fencing off the pond may be the answer. Muddiness due to soil type and water chemistry is the most difficult to correct.
Usually the fine suspended clay particles found in muddy water have a negative charge which keeps them in suspension. Organic matter usually has a positive charge which attracts and binds the suspended particles together and helps them settle to the bottom.
A simple test is to collect a sample of water from the pond/lake and place it in a clean glass one gallon jar. Add two tablespoons of vinegar to the sample. If it clears up overnight, chances are that treatments with organic matter will probably work.
One such treatment is to place two small square bales of good, dry, green alfalfa or clover hay, per surface acre of water, in the water along the edge in early Spring or summer. Anchor the bales in place in shallow water. The treatment
will not be effective if all the hay is placed or blown into one corner of the pond/lake. Reapply the bales at 14 day intervals until the water clears, but no more than four applications should be made each year.
Cottonseed meal, applied at 75 to 100 pounds per surface acre of water, has also been used with success. More than one application of cottonseed meal may be necessary at 14 day intervals until the water clears, but not no more than three applications is recommended each year.
In some cases, the addition of agriculture lime, up to 2 tons per surface acre, have reduced pond/lake acidity enough to settle the soil particles. Take a sample of the pond/lakes bottom mud, dry it and have it analyzed to determine the alkalinity content. Most businesses that sell and spread lime for agriculture purposes have the ability to test the sample.
The Missouri Department of Conservation has an aquaguide, which is available for the asking, titled
"Clearing Muddy Ponds With Gypsum".
Management of aquatic plants: Rooted aquatic plants are an important component of a pond/lake's life cycle. They help keep the water oxygenated, provide food, cover and nesting sites. They reduce shoreline erosion and provide homes and food for a variety of aquatic insects. These insects and their larvae are important food sources for fish and other aquatic animals. Fish growth for a variety of species is enhanced when aquatic vegetation is managed at moderate levels.
Ideally, aquatic plants should cover 15 to 20% of a pond/lake's bottom and surface. Conversely, too many aquatic plants are not good either. Besides making fishing difficult, excessive vegetation may provide too much cover for baitfish, which reduces the availability of food for predator fish and could result in an over population of one or more species of fish.
A pond owner has three options for controlling aquatic vegetation; mechanical, chemical and biological. Mechanical is time consuming and chemical treatments are usually expensive but both work well for spot treating in a specific area. Introducing grass carp as a biological control can generally reduce vegetation throughout the pond/lake. Sometimes the best solution for managing aquatic vegetation is a combination of two or all three controls. If grass carp are used as the primary control of vegetation, keep stocking rates conservative to avoid total eradication of aquatic plants.
Fish species present: Most stocking strategies require predator fish to keep reproduction in balance, especially if the stocking objective is to grow large fish. Largemouth bass is usually the recommended predator fish for stocking in Missouri pond/lakes. Its reputation as a sport fish is without rival and largemouth bass have the ability to adapt to a wide range of water parameters.
We at Country Fish Farm, LLC understand everyone has different goals and purposes for stocking fish. We will provide you with sound management advice and guide you so
your stocking objectives will be met. However, sometimes, its is difficult to blend several stocking objectives into one pond. For example, it would be difficult to establish a stocking strategy for growing several species of trophy size predator fish in a 1 acre pond because most will compete for the same food.
Carrying capacity: Every water impoundment has a limit of how many pounds of fish it can produce naturally. This is referred to as the carrying capacity. The carrying capacity can be altered and depends on the level of management one is willing to apply to meet specific stocking objectives. The manipulation of fish, the habitat or both is called
management. The lowest level of management is the production of fish based upon a pond/lake's
natural carrying capacity. Production can be increased by supplementing the food chain, such as feeding a commercial fish feed and/or providing increased oxygen through aeration for higher demands and so on.
Supplemental feeding: Supplemental feeding to increase growth rates of fish is highly recommend,
especially in the Ozark portions of southern Missouri, where pond fertility is low. Supplemental feeding not only increases growth rates of fish but also improves the condition of fish and enhances their reproduction. A feeding program that is properly managed benefits all fish in a pond/lake, either directly or indirectly by reducing the consumption of the natural food chain.
Good record keeping means better fishing. There are approximately 300 - 400 thousand privately owned pond/lakes in Missouri. With this in mind, and recognizing that governmental budgets are continuously being cut for various reasons, one could expect a long waiting list to have a pond/lake shocked to determine the status of its fish population. Research has also indicated that shocking several spots in a water impoundment to determine the condition of a fish population is not as precise as once believed.
The alternative is maintaining a good record of fish being caught. If you supply good information about your fish population to us or to a Missouri Department of Conservation fisheries biologist, he/she will be able to prescribe recommendations to improve your fish population and provide specific size and harvest limits for your pond./lake. You can keep track of the species and sizes of fish caught by using the
"Good Record Keeping Means Better Fishing" aquaguide, which is available upon request from most Missouri Department of Conservation Offices.
Catch the big one in your own pond/lake: Growing large or trophy fish requires some degree of management, prior
planning and a little time and work; but it is a challenge that leads to better fishing. Who knows, maybe your pond/lake will produce the next state record bass, bluegill, crappie or what-ever!
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