Catfish Culture, Management and Harvesting

Marketing

A marketing plan should be the first step taken when one is considering catfish production. No profits are made until your crop of fish is sold. Catfish are sold in all forms of their life stages. Egg masses are sold by the pound, and the price changes annually depending on the supply or success of local hatcheries in spawning fish.

Catfish fry are sold by the piece, and fingerling fish longer than 1-inch are usually sold singly by the inch up to about six or eight inches; longer fish may be sold by the pound. Food fish are normally three-fourths to two pounds in weight and are sold by the pound. Some specialty markets exist for brood fish, especially if they are an improved or selected strain. Albino catfish are a novelty sometimes sought by fee-fishing operations or the aquarium trade.

Retail Markets

Retail marketing is practiced mostly by smaller, commercial farms. The small farms usually cannot take advantage of discounts for bulk purchases of feed and seed stock. Production costs per pound of fish produced are usually higher than those of larger farms because of the economy of scale. Ponds are often smaller and more costly to build per acre. Profits may be low if fish are sold to a processor wholesale market. Retail prices are usually influenced by local competition, if any, and advertising is usually required to be successful. Fish are sold undressed or live through fee-fishing ponds, out of holding tanks or when harvested. Fish can be sold off trucks in areas where there is demand.

Other retail markets include local stores and restaurants. They usually want processed fish delivered on a regular basis. This means regular harvesting and the ability to hand-process fish.

Retail markets also exist for the sale of catfish fingerlings or stocker fish. These fish are marketed primarily to people who have recreational or farm ponds. A higher price is usually obtained compared to wholesale sales to commercial farms. Advertising is required, and live fish need to be transported and delivered to the customer?s pond. This can be a good business; a quality product and good service are required. It is preferable to be in an area where farm ponds are numerous.

Economics

Taking the plunge into catfish farming should be done only after careful economic planning. This may not be as complicated as you think. A good way to start is to list the income and expenses you expect. First, consider the income your fish farming operation will produce. Generally this means estimating the amount of fish you will produce and the price you will receive for them.

Next, make a list of the expendable items you will need to buy each year to produce your fish. This will include feed, fingerlings, labor, fuel, electricity, equipment, repair, interest on borrowed money, etc. These are your variable costs.

Finally, make a list of costs for everything associated with machinery. These are your fixed costs. Examples include pond construction, wells, pumps, trucks, feed bins, tractors, aerators and buildings. Do not overlook the cost of buildings, tractors or other equipment that is already purchased. They should be charged off some each year of the expected life since they will eventually need to be replaced. Equipment used for other jobs on the farm also needs to be partially charged so each enterprise can stand on its own.

One major reason to estimate income and expenses is to be able to project your return or profit. Another use of the same numbers is to project a break-even cost for what you produce. To get these critical numbers you will need to organize your information into a form known as an enterprise budget. Your numbers are already divided into three lists: income, variable costs and fixed costs.

Do not get discouraged if the estimated return is tiny or even negative. The first budget is just a starting point. Consider ways to reduce your costs. Doing your own pond construction work with used equipment could reduce pond construction costs by half.

Another way to reduce costs would be to use your own funds instead of borrowing.

Pond Site Selection

Subsoils. A suitable pond site should have a soil type and composition that holds water economically. The soil should contain preferably at least 20% to 30% clay by weight to minimize seepage. Areas with pockets of gravel, rock fissures or sand should be avoided.

Topography. The topography is the lay of the land. It can be flat or hilly. The topography determines the amount of dirt that has to be moved and also the size of the pond. The topography around ponds should permit drainage by gravity flow during any season. Make sure that ponds do not block drainage from a neighbor’s land or interfere or cause any damage off your property. Good drainage is important because eventually ponds will require complete draining for repairs, maintenance and to reestablish fish inventories.

Water Supply. Catfish are raised under various management levels using different sources of water. The intensive production of catfish requires a dependable year-round supply of water. Water pumped from surface waters in rivers or streams is less desirable for intensive production, but must often be used in many situations. Activities upstream or in the watershed can contaminate the water and silt loads often are heavy. Undesirable wild fish are more apt to enter ponds, and disease transmission is more likely.

General Location. Take precautions if the site is in a flood plain or low-lying area. Severe flooding can damage levees and ruin a fish crop. Wild fish may enter ponds through open drainpipes, and pond draining may be impossible during times of flooding.

Stocking

Fingerlings six inches or longer are stocked into growout ponds with the goal of producing a market-sized fish. The number of fish stocked at this final stage in the production cycle varies widely. Factors that determine a suitable stocking rate include amount of time that the producer can spend with the fish, experience of the producer, desired fish size at harvest, maximum daily feeding limit, availability of water and aeration equipment, and length of culture period.

The size of fish desired at harvest should be acceptable to customers and economical to produce. A good money-making fish for the producer is a fish weighing between 0.5 – 0.79 kilo that converts feed efficiently, gains weight well and does not take too long to produce.

Feeding

Feeding is the most important task in the intensive pond production of catfish. In a normal situation, catfish can be seen only when they are coming up to feed, and their feeding behavior can be an important clue to general health and the pond condition. Potential problems with the fish or pond water quality can be recognized early by noticing abnormal feeding behavior.

Feeders

Catfish may be fed by hand from the bank or boat, or by using some type of mechanical feeder. Hand feeding more than 10 acres of intensively cultured catfish ponds is too time consuming and laborious, thus some type of mechanical feeder should be used on larger farms.

Feeding Rates

Several factors affect the amount of feed a catfish will eat, such as:

  • water temperature
  • water quality
  • size of the feed
  • palatability or taste of the feed
  • frequency of feeding
  • the way fish are fed
  • location of feeding sites
  • type of pellet used (floating or sinking)
  • health of the fish
  • size of the fish

Feeding Practices

Manner and time of feeding, as well as the amount and type of feed, can have a profound effect on the growth and size variation and the quality of the catfish produced. A large variation in the size of catfish produced usually is the result of underfeeding (feeding the fish less than they should have) or feeding in a small area of the pond. In underfeeding, the larger, more aggressive catfish eat a larger share of the feed and become bigger at the expense of the smaller catfish.

This also happens when feed is offered in only a small area of the pond since the larger, more aggressive catfish quickly learn where the feed will be put in the pond and are there waiting for it. Thus, to produce catfish uniform in size, and to maximize profits, it is equally important that catfish are fed the proper amount of feed daily and the food is distributed as evenly over the pond as possible.

Feeding twice daily, if possible, will usually improve feed consumption and feed conversion. This means that one-half of the daily allowance is fed in the early morning, and the other half later in the day. If the catfish are fed only once a day, morning is the preferred time since feeding in the late afternoon increases the amount of fat deposited, and this can affect the quality of the processed fish.

Feed should not be offered until the oxygen level of the pond water is at least 4 parts per million (ppm) or higher because feed consumption goes down dramatically at lower oxygen concentrations. Oxygen requirements for catfish increase greatly during feeding, so it is best not to feed in the early evening when oxygen concentrations in the water are decreasing.

Record Keeping

You must be able to closely estimate the number of fish and the weight of fish in every pond at any given time if you want to be successful at raising fish. If the weight of fish in a pond is underestimated, not enough food will be fed, resulting in poor growth, poor feed conversions, and increased time required to get the fish to harvestable size. If the weight of fish in a pond is overestimated, the result will be overfeeding, poor feed conversions, and very likely, severe water quality problems.

Water Quality

Maintaining good water quality in production ponds is absolutely essential. Failure to do so will result, at best, in poor growth and high feed conversions or, at worst, a total loss of all fish in the pond. Remember that the fish in the pond are living in their own wastes. Thus, the weight of fish that can be produced in a pond is limited by the ability of that pond to provide adequate oxygen, (not only to keep the fish alive but to enable them to metabolize their food and grow) and to break down nitrogenous wastes.

Harvesting

Different methods can be used successfully to harvest fish. The method used depends on the production system, type of pond and harvest strategy. Fish can be harvest by fishing, trapping or seining.

The only way to harvest all fish from a pond is by draining. When complete harvesting is desired, fish are removed by seining and the few remaining fish are harvested by dipnetting. Harvesting the last remaining fish (scraping out) from a pond is time consuming, especially if many pot holes or low areas exist in the pond basin. Draining ponds and refilling means lost feeding days and a fuel bill if pumping is required.

On commercial farms, seining is the most efficient method to harvest a predictable large volume of fish with one effort. For hill or watershed ponds with deeper water, and irregular bottoms and banks, partial harvesting can be done by trap-seining using various techniques. Trapping fish with a seine is best accomplished when fish are feeding well and ponds are several acres and larger. Fish can become wary of this method and difficult to catch unless it is used infrequently (only once every week or longer).

In small ponds, large lift nets with centrally located feeding rings have been somewhat successful when used infrequently. Many producers use a seine to harvest only the market-sized fish from levee ponds that have graded bottoms. This method is often referred to as topping and became popular in the 1970?s. A seine with a selected mesh size is used along with other grading devices to capture fish of a desired minimum size; smaller fish remain in the pond.

Transporting

Catfish, like other livestock, are sensitive to changes that occur when they are handled. Transportation stresses fish due to crowding, changing temperature conditions, and general over excitement from handling. Fish may become spined or water quality conditions can quickly deteriorate. Fish have to be in good condition and healthy before they are transported. Sick or weak fish will probably die, or a disease problem will worsen. Fish not handled properly may develop a disease or die one to seven days after they are transported.

The following steps should be taken to prepare fish for hauling. Do not feed fish for at least two to three days in the summer and four to five days in the winter before they are transported. Fish with full stomachs handle poorly, and any regurgitated food or expelled fecal matter fouls the hauling water.

Fish should be hauled at cool water temperatures to lower their metabolic rate, calm them and lower their oxygen consumption. In summer, fish should be hauled in water 16º to 18ºC.

Transport fish in good quality well or spring water if possible, rather than pond water, unless the water is cool and clear, or if only a short trip is required from pond to pond. Pond water with an algae bloom should be avoided unless absolutely necessary and the trip is short.

Handle fish during the coolest time of the day, and avoid time out of water, especially when it is hot or windy. Do not overload dip nets and loading baskets, and try to move fish in a cushion of water.

Download complete manual here

source: Compiled and Written by Robert M. Durborow, Ph.D., Associate Professor, State Extension Specialist for Aquaculture, Aquaculture Program, Kentucky State University, Frankfort, Kentucky www.ksuaquaculture.org

Leave a Reply

Your email address will not be published. Required fields are marked *