 Commercial fish farming is a fast-growing industry in the United States generating millions of dollars at the farm level. To earn top dollar and become a successful producer in this competitive business, you must know how to properly harvest, handle and transport your delicate aquatic crops. Keeping fish healthy throughout the harvesting, handling and transportation stages of your fish farming operation is essential. The process begins by thoroughly planning your harvest. First, arrange for good labor, equipment and supplies. Even the time of the year when you harvest is important. Cool weather is ideal because winter and spring rains can refill ponds and lower pumping costs. Fish stress problems that are often prevalent in hot weather can also be eliminated. Unless you have all-weather access roads and main levees with gravel or asphalt tops, don't harvest during and immediately following heavy rains. Large equipment and heavy vehicles can damage unprotected roads and levees. With the wide variety of nets and sands used in harvesting, you'll need some knowledge of how each functions. Cast nets are inexpensive and useful for sampling fish and with practice and patience, anyone can learn to throw them. These nets have one major drawback. Fish with spines tangle easily in the mesh. Mesh size and texture are two important considerations in the selection and use of various nets. Your choice of a mesh size is determined by the size of the fish you plan to harvest. Avoid purchasing a net with a mesh too small because fish with gills become easily entangled. Familiarize yourself with nets having various textures. Net texture is determined by the type of material and how the mesh is woven or formed with knots. Nylon nets require a coating to prevent catfish from getting caught by their spines. Polyethylene nets work fine without a coating. Although a net containing knots is suitable for catfish, most scaled fish require a soft, non-coated net without knots. Carp or buffalo fish are the exceptions and can be harvested with knotted nets. Sains are the most common type of net used in harvesting. They work well in ponds having a regular shape, a depth of 5 to 8 feet, and bottoms that are flat with no obstructions. A good rule to follow in purchasing a sane is to select one with a length that is one and one-half times the widest distance of the pond. In turn, the corresponding depth of your sane would be one and one-half times the deepest water found in the pond. The bottom line of the sane can be heavily leaded or have a many ends sysil mudline. It can also have a 2-inch diameter mudline made of knotless nylon netting or rollers. Avoid using a sane with a small mesh in large ponds. It's harder to pull because of resistance caused by mud not being able to easily sift through the net's small holes. Fish in large ponds are harvested with a hydraulic sane reel on a trailer. The reel is used to transport, store and beach the net. Some systems feature hydraulic controls that pivot the reel to various angles. As you make plans to gather your fish, you'll need to decide on the type of harvest that best fits your operation. One option is a partial harvesting that takes some of the fish from the pond. The second method is a selective harvesting process used to top off a pond and remove only the larger fish that are suitable for marketing. Many catfish producers prefer to use this method to harvest only the larger market-sized fish from a pond containing different size fish. The last harvesting technique is known as clean cropping, which removes virtually all of the fish. The only reliable way to harvest all fish from a pond is to drain it completely after most of the fish have been sined. As the harvest approaches, don't forget to take your fish off of feed. One or two days ahead for a summer harvest and three or four days in advance for a winter harvest are sufficient. The type of equipment and number of workers you'll need to gather your fish depends on the size of your ponds. A saining crew for a large pond consists of five to seven workers. Two to four people are needed inside the pond to keep the weighted line on the bottom. Two are used to drive the tractors. The remaining worker operates a boat used in dumping mud from the bottom line. An experienced crew can sane a pond and have fish ready for removal in one to two hours, depending on the size of the pond. Once the lead lines reach shore, the net is closed off at both ends. The fish are then concentrated with the help of a special net called a sock. If the fish are going to be gathered right away, make sure the depth of the water is at least two and one half to three feet deep. Begin the harvesting operation by attaching the funnel end of a sane to a metal loading frame that secures a device called a live car. The metal loading frame sets up a narrow chute that funnels fish into the live car as the sane is reeled in. The live car crowds the fish so they are easily transferred from the pond to a hauling truck. If it's necessary to land your catch in shallow water, particularly a large number of fish, try this harvesting variation. Stake out the sane, but don't attach the live car once the fish are crowded. Manually pull a short cutting sane to roughly grade and concentrate the fish for loading. If fish require overnight holding, leave them in the large area of the staked harvesting sane. Instead of saning an entire pond, there is another way to harvest your catch. This method uses feed to lure fish into the net. To work well, this procedure relies on a sane that is at least 200 feet long to work well. The success of this harvest technique depends on a firm bottom in a pond that is free of debris and less than five feet deep. To begin this type of harvest, place a sane in the water parallel to the bank or across a corner. A pull rope staked on the bank easily retrieves the net. Next, place feed outside the open end of the sane. Then use a trail of floating feed to lure fish to the net. Once the fish are inside, pull the coiled ends to shore. Take care to follow your normal feeding routine when harvesting fish in this manner. The only variation is to use less feed than usual. Mating with feed is more effective during warm water months when fish feed actively. Remember, once you employ this harvesting technique, it takes seven to fourteen days before fish lose their shyness. Only then can this method of crapping be used again. Small ponds less than several acres in size require less equipment than large ones. Fish are gathered by manually pulling a sane or using small tractors, trucks or four-wheelers. The most important thing to remember in small pond harvesting is to pull the sane slowly and carefully as it's dragged to shore. This precaution will keep the lead line on the bottom and your fish in the net. Harvesting is extremely difficult in watershed ponds that are more than ten feet deep. The job becomes easier if the water is drained to a depth of six or eight feet. Time of the year and temperature are two important factors to consider in making plans to gather your catch. They determine if fish must be removed from the pond shortly after becoming concentrated or whether they can be held for a longer period of time. During cool weather it's possible to contain your catch anywhere from two hours to overnight if temperatures fall below 60 degrees Fahrenheit. Fish are kept from jumping out of the net by a double float line on the live car. Be sure to move the fish from shallow to deep water and use harvesting stakes to secure the underside of the sane to the pond bottom. Keep the float line about one foot above the water surface. Before leaving the net unattended, make sure the sock is firmly anchored. Otherwise, currents from a well or aerator can roll up the live car and cause the fish to die. If fish are going to be held overnight, remember there's a possibility of someone stealing your catch. Holding fish during the summer is risky because heat stress can strike if temperatures reach above 80 degrees. If this happens, load your fish for transport shortly after concentrating them at the end of the pond. In fact, it's a good idea to have fresh well or spring water available for such high heat conditions. Then if pond water becomes too warm when you concentrate your fish, cool water can be pumped in to alleviate this problem. Well or spring water is also ideal to use inside your transport tank for hauling fish. Large fish concentrations in warm weather climates are commonly transferred from the pond in loading baskets attached to a hydraulic boom. Fish weights are determined with inline spring loaded or electronic scales. Remember to use a coated net for harvesting catfish and avoid overloading the basket if fish are to be restocked in a pond or hauled on a long trip. Overloading can severely injure fish. Another fish loading method relies on a dip net to put fish into buckets or tubs filled with clean water. This method works well for small delicate fish where special handling is required. Water quality deteriorates quickly when fish are concentrated in buckets, especially in warm weather. If this procedure is used, fish must be moved in a hurry. A fish pump is an alternative piece of harvesting equipment used to quickly move fish safely from the water. They range from pumps mounted on transport trucks to portable units. Although pumps are primarily employed in the trout industry, they're being evaluated for possible use with warm water fish. When using a pump, it's necessary to crowd the fish inside the net. Next, place the pump intake where it can easily move fish and water to a dewatering tower or box. As the fish are loaded into the transport tank, the water is returned to the pond. With this type of pump, the weight of the fish is determined by water displacement. This method is quick and not overly stressful on fish. Many transport tanks have a water displacement tube on the outside of the tank or a viewing plate in the tank wall to assist in calculating fish weights. For baitfish producers, saining is a faster harvest method than using lift nets. The best method for gathering fish this size is to crowd them into the bag of the sain, then transfer minnows into a floating holding box that has nylon walls. If you raise fry, short common sense minnowsanes work well for harvesting fish in tight schools. For best results, try pulling the sain manually or use it like a dip net from a boat. One decision you'll need to make in advance of the harvest is how to grade your catch. Fish sorting is done either in the pond or in a special holding facility. You can first rough grade your fish inside the pond by using a sain or a live car with a mesh size that captures only fish of a desired size. During winter harvests, use one mesh size larger than normal and allow grading to take place overnight. For in pond sorting, place the middle of the live car across the top of a boat to form two compartments. If large fish of one species are mixed in a pond with several other species, they're best removed by using a greater sain inside the harvesting net. Greater sains are similar to cutting sains. In fact, some harvesting sains have grading panels at the ends. This net alteration allows the end panels to be used like a cutting sain for grading fish. Large grading boxes that float are used in ponds to sort minnows and other species. They're ideal for holding ungraded fish that would normally require additional handling. Use a dip net to load fish in the boxes. Remember to select a coated net for catfish and one made of soft nylon without knots for minnows and other delicate fish. After the fish are rough graded in the pond, they can be moved to another location for further sorting. One system uses vertical panels containing bars with different size spaces between each to sort fish. The fish are either crammed together in this sorting system with a crouter panel or a grater panel is slid to one end of the tank. Blocking screens inside of the tanks keep different grades of fish separated. Some large panels have wheels for easy movement. After the fish are harvested and graded, they're ready for transport. The time fish are en route can vary from less than half an hour to more than 24 hours. To ready your fish for hauling, remember these four important rules. First, load only healthy fish. Next, keep fish at the right temperature. Third, don't overload. And finally, use reliable, well-maintained equipment. Fish loading rates is an expression you'll sometimes hear in the fish farming business. This term refers to the pounds of fish per gallon of water before any fish are added. Specific information on recommended loading rates for the different species of fish and their various sizes is available from the Southern Regional Aquaculture Center. Besides adult fish and fingerlings, even the eggs and fry of some species are often transported. Catfish eggs are generally shipped in plastic bags filled with pure oxygen and water for periods ranging up to 24 hours. The best method for shipping fry is in square bottomed bags. To transport fry, carefully acclimate them to the water they're being shipped in if the temperature varies more than 5 degrees Fahrenheit from the water they're in. Prepare the fry for transport by filling 1 fourth of the bag with water. Then add the fry. Next, remove the air. Refill the bag with oxygen and seal tightly. Place the bags in a cardboard or styrofoam box for protection and insulation. Fry are best moved from indoor facilities to an outdoor pond in small transport tanks. First, gently transfer the fry into a bucket. Pour them into the transport tank containing a mixture of hatchery water and pond water. Avoid direct handling of the fry by unloading them at the pond site with a flexible hose attached to the drain of the transport tank. Transport tanks vary widely in design, construction, material and size. For this reason you'll need to determine what best fits your needs before investing in a system or transporting your fish. Most tanks are made of aluminum or fiberglass. If you live in the southern United States and plan to haul fish long distances in the summer heat be sure to use only well insulated tanks. Hauling tank capacities range from 50 to 2,500 gallons. Sloped tank bottoms allow fish and water to drain easily. A sliding gate inside the tank controls the discharge of water. Internal tank petitions called baffles are important because they prevent severe water sloshing. Tanks can be made portable by securing them with J-bolts to a flatbed or by attaching them directly to the truck frame. Gooseneck trailers with electric brakes are also ideal for carrying transport tanks. Regardless of the transportation method you select for your tank remember to comply with safety regulations and follow recommended gross weight limits for vehicles and tongue weight regulations for trailers. Some states require special markings on fish transport trucks so before conducting interstate business check with the proper regulatory authorities for current laws and regulations to follow in hauling and marketing live fish. When you move fish use only high quality transport water although cool water from a well or spring is ideal it may require some oxygenation before fish are loaded. Always check for adequate water quality in the tanks before adding your fish. Avoid using pond water for short trips if possible even if it contains adequate oxygen and never use water from a pond containing a heavy bloom of algae. Ammonia buildup in transport tanks is best controlled by withholding feed before transport using clean water and lowering water temperature. An adequate dissolved oxygen concentration during transport is essential. Unless a continuous supply is present oxygen is quickly depleted when large numbers of fish are transported at one time. To haul large fish concentrations an oxygen level above six parts per million must be maintained. Most haulers depend on bottled oxygen or liquid oxygen. A regulator is used to maintain and adjust oxygen supply rates to each compartment through peration lines. Oxygen is dispersed by various types of diffusers and appears as fine bubbles rising from tank bottoms. Some fish farmers use 12 volt mechanical agitators alone or in combination with bottled oxygen. For agitators to function properly the transport tank must be filled and kept level at all times. It's also important for agitators to operate at the design paddle depth for efficiency and to extend motor life. Small fish can be kept from passing through the agitators mesh basket by covering it with one eighth inch hardware cloth. Although a combination of agitators and bottled oxygen works well for short trips and as an emergency backup system pure oxygen is extremely beneficial for long trips. Highly dependable liquid oxygen is often used to avoid excessive agitation when transporting small fish. A variety of chemicals can be added to the tank to reduce stress brought on in the handling and transportation of fish. Mix the chemicals into the tank before loading the fish. If fish food are being transported choose only those chemicals approved by the Food and Drug Administration. For information on specific chemicals and treatment rates contact an aquaculture specialist with the Cooperative Extension Service in your state. If fish are transported from one pond to another use a pump to mix some pond water with tank water before unloading your harvest. If tank and pond water temperatures differ more than 10 degrees Fahrenheit acclimate fish with this water mixture at the rate of about two minutes per degree of difference. Avoid using a dip net to unload fish if possible. Instead use a chute to stock the fish directly into the pond. If you raise a species of fish that's fragile remember they're best handled during the early morning hours when water temperatures are cooler and sunlight is less intense. Ideal temperatures for harvesting such delicate fish as golden shiners striped bass and striped bass hybrids are under 65 degrees Fahrenheit. Higher temperatures require special precautions for handling these fish species. Fragile fish benefit from a mild sedation before handling. Keep oxygen levels in transport tanks high right after loading. Proper oxygen levels are critical at this time because fish consume higher rates. The best way to handle delicate fish before a long transport is to cure or harden them in a holding vat. This takes at least 24 hours and allows fish to empty their stomachs and adjust to cooler temperatures. In fact this method is preferred over loading directly from a pond during the summer. Block ice is an idea for lowering water temperature. Remember that excessive use of ice made with chlorinated water can harm fish especially if they're in a small amount of tank water. To warm the water place your transport unit in sunlight with tank doors open and add well water in the winter. No matter what species you're handling keep in mind that stress accumulates as fish are gathered from a pond, taken to their destination and restocked in another body of water. Fish losses caused by stress may occur in a few days or several weeks after the fish are unloaded. You can minimize stress and injury to your fish during harvest, transport and unloading by using the proper equipment and recommended practices. Never use graders with abrasive surfaces and avoid unnecessary chemical treatments that may weaken fish prior to hauling and dry or disinfect the transport unit and any nets between each load of fish. Always take the necessary time to properly plan not only for transporting your fish but for harvesting and sorting as well. And as you make plans keep these points in mind. For the harvest use adequate labor and good equipment. Know what's in your pond. Do the job right the first time and minimize stress in handling fish. During grading sort for economic reasons. Grade as many fish inside the pond as possible. Use the proper equipment and handle fish carefully. To transport your harvest load only healthy fish. Hold the tank water temperatures at the proper level. Don't overload fish. Keep your equipment well maintained and have essential spare parts available. Remember that it takes a high quality fish to live for many months after being handled in comparison to one that will be processed shortly after harvest. Success in the harvesting grading and transportation of your fish greatly depends on how well you stick to accepted practices. Always evaluate new ideas carefully and test them on a small scale. This will help you avoid the risk of a major loss or a bad business reputation. Good luck in your fish operation.