This manual describes what good quality fry is and what should be done to ensure good quality.

Transcription

1 FRY/SEED QUALITY AND STOCKING INTRODUCTION Fry is the young fish that is stocked in ponds to grow; harvested and sold. When the fish is just hatched it is called "fry" when it has grown to a size similar to; human finger, it is called "fingerling" This manual describes what good quality fry is and what should be done to ensure good quality. In commercial aquaculture, the farmer aims at producing fish for profit in the shortest time possible. The farmers' earnings and profit are reduced under the following circumstances: If the size of the fish harvested is small and is rejected at the market or only sold at low price. If the harvest is of mixed sizes and only the large fish is selected out for sale and the rest is rejected. If the harvest consists of a mixture of fish types and only one is popular in the market. Only a proportion of the harvest is sold at good price. If the fish grows so slowly in a particular region, it takes a long time to reach market size. The farmer spends more money in feeding the fish to attain market size. The type and quality of fry stocked is often the main cause of the above cases in which case the earnings and profits of the farmer are reduced. It is therefore advisable that the farmers stocks good quality fry. FRY QUALITY 1. What is good quality fry? The good fry is that fry that will produce the most profitable harvest at the shortest possible time. The following are the qualities of good fry: Fish will grow fast and reach market size quickly Fish gains the largest weight for every weight of feed given Fry that is composed of only the fish type popular in the market, not mixed. All the fish, and not only some, will grow at about the same pace to be harvested and sold together. 2. How does one tell poor quality fry from good quality fry? The characteristics of poor quality fry include the following: Fry of mixed fish types is not good fry: This often happens when farmers do not get fry from a designated fry producer. Examples: farmer-to-farmer fry supply or from the wild streams, river & lakes. The farmer is sorting out what to sell. Carp may sell at a lower price because Ugandan fish farmers are not familiar with it. The farmer gets less money. Instead of selling 25kg the farmer only sells 10kg. Fry of one fish type at a time is good.

2 Fry of mixed quality and fish type Fry of mixed age or size groups is not good quality: Size normally indicates age. Therefore, the bigger fry are older than the smaller ones. Fry of mixed sizes are usually found when fry is collected from ponds not intended specifically for fry production (farmer-to-farmer fry supply), or when it is collected from the wild (streams, river & lakes). Fry of mixed sizes or ages result in mixed size harvests as shown in figure 3.2. In most cases the older fish start reproducing in the pond and congest the pond much earlier when majority of the fish are still small. The stunted fish are sold at a reduced price and the farmer loses money. A harvest from fry of mixed sizes and age groups

3 Fry of uniform size/age is good. Size indicates age. Therefore uniform size is also uniform age. In the Catfish ("male") fry, when some individuals are larger than others, the larger fry feed on the smaller ones. When fry of varying sizes is stocked, the overall harvest is low, consisting of few numbers although their sizes may be big. A harvest from uniform fry groups Stunted fry is not good: Stunted fish is fish that is too old for its size. It is usually a result of inadequate feeding of fry or feeding with poor quality feed. The fry remains small while the age is advancing. The easiest way to recognize stunted fry is large heads with bulging eyes contrasted with its small body size. Any lame (diseased) fry is not good for stocking: There are several types of fish diseases. A diseased fish does not grow well and may die. Fry showing any signs of disease should not be accepted for stocking. Lameness usually affect the skeleton and the fish does not grow well. Fry showing any sign of disease is not good for stocking. Fry may be lame (with deformities) as a result of: serious injuries acquired due to bad handling feeds that lack certain nutrients (especially minerals & vitamins) a heritable factor (gene) diseases A fish with a diseased mouth Fry that is badly injured: Injury results when fry is badly or roughly handled. The bruised fry may get an infection and die. Or it may take sometime for the wounds to cure. During that period, it does not feed and it grows slowly. It is small at harvest. Fry collected from the wild (stream, river or lakes) is not good. Fry of poor genetic quality: Fry may be of poor quality because of factors inherited from generation to generation (genes). External signs of genetic quality may not be obvious to ordinary people. They may not tell in advance

4 that it is poor fry. They only find that the fish does not grow well. How to identify poor genetic quality of fry is not in the scope of this manual. The only way to avoid these uncertainties is to get the fry from a certified fish breeder. Appendix i is the list of currently recognized fry producers. 3. The results of stocking poor quality fry as compared to good quality fry 3.1. The results of stocking fry of mixed sizes or fish types When such fry is stocked in a pond, the harvest will be of mixed fish types, some of which may not be popular in the market and will be sold at low price. Usually fry size indicates the age of the fry. Stocking mixed size means some fish are older than others. When fry of different sizes are stocked together, the few older fish mature earlier and start reproducing while the rest are still growing. Because of the increased numbers, all the fish stop growing (get stunted). The harvest consists of very few fish large enough for the market and the rest are too small and are rejected by the market. A harvest of mixed fish types (Mirror carp, "kibaati" and "lukka") and mixed fish sizes resulting from fry of mixed fish types and sizes In figure above the farmer is sorting out the few larger fish to sell at a good price. The rest are sold at very low price. The market may offer higher price for "Kibaati" and reject Carp. The farmer may get only 30% of what he should have got The result of stocking fry of the same fish species and of uniform size If the farmers stocks only the fish type that the market desires (say, "kibaati") at uniform size, all the fish will grow at the same pace. All of them attain market size at the same time (see figure below). The uniform fry produces uniform size harvest and all the fish is sold at good price. There is no need for sorting what to sell. A Fish of the same age & size 3.3. The results of stocking stunted fish The farmer spends money on feeding; hoping that the fish will grow bigger. The fish does not grow bigger. Instead it matures and reproduces at small size. The result is that the pond gets filled up with many small fish that is difficult to sell at good price. The farmer loses profit.

5 3.4. The results of stocking lame fish A harvest of lame carp among normal ones. Only the normal ones can be sold. Note the lame fish grew slowly Lame carp 3.5. The result of stocking diseased fish A diseased fish may not feed comfortably. It does not grow well and if not treated it may die.nobody would like to buy such fish to eat. 4. Recommendations on quality of fry Farmers should purchase fry from well-established fry producers. These are the fry producers certified by the Fisheries Department. See the list of the certified seed producer in Appendix. Complaints about bad fry can be registered with the Commissioner for Fisheries, Department of Fisheries Resources, Entebbe, Box number 4, Entebbe, Telephone Farmers should avoid collecting fry from the wild for stocking their ponds. Its quality is not known. Both the fry producers and the farmers collecting the fry to stock are responsible for avoiding injuries on the fry during fishing and handling during transportation 5. Preparation of ponds for stocking The ponds to be stocked must be prepared adequately before stocking. Pre-stocking preparations includes the following:- 6. Preparation of new pond for stocking a. final finishing (for new ponds), removal of mud and repairs (old ponds) b. Liming the pond. c. Fixing pipes and screens. d. Fertilizing the pond. e. Filling the pond with water. f. Allowing time for the pond to turn green a. Fixing inlet and outlet pipes The pipe to let water into the pond (inlet pipes) is fixed at the shallowest point of the pond. And the drainage pipe is fixed at the deepest end of the pond. The inlet pipes must be screened to keep away wild fish from entering the pond. A netting material with very fine mesh is used.the pond is fertilized first before filling with water. a. Fertilizing the pond

6 Pond fertilization is done to allow growth of natural foods for the fry to be stocked. If fry is stocked before building up the quantity of natural foods, the fry may starve or grow slowly and become stunted. Several materials can be used for fertilizing ponds, including agricultural (also called inorganic) fertilizers and manure (called organic fertilizers). Agricultural or inorganic fertilizers: These include: NPK, TSP, SSP, Urea, All these are in powder or granular form, they are available in shops selling Agricultural chemical. Details are given in Section 4 Organic fertilizers (manure) The sources of manure include chicken dropping and urine Cow dung and urine Pig dung and urine Compost Sunflower cake The details on how to apply fertilizers is given in Section Four. When the pond has developed these organisms (algae) turned green, it is ready for stocking If fry is stocked before sufficient food has grown in the pond, the fry will not grow well. 7. Preparation of pond that previously had fish For the pond in which fish have already been grown, there is no need to go through the whole long process required for the new pond. The important points are: To completely drain the pond, remove all the fish (fry or eggs) that may have remained from the previous harvest, To kill off all the germs and other animals that may be at the pond bottom (eg tad poles, frog eggs, insects, etc) To allow the pond to completely dry up so that the mud breaks up) After drying the pond, it may require some repair work before it is ready fro re=stocking, 7.1. Removing the bottom mud, Mud accumulated in the pond comes from two sources: Banks that keep collapsing and falling into the pond, and The remains of manure and other feeds that were given to fish and the feces that fish produce. It is important to remove the mud because it reduces the productivity of the pond. It may also be prone to disease. the mud becomes lighter and easier to remove After drying it. It is simply scraped from the bond bottom using hoes or shovels (see figure below). Farmers removing mud from the bottom of pond

7 The lighter surface mud, rich in manure, should be carried away and used to fertilize gardens. The more firm mud should be used to build back the pond dyke that has collapsed or is in danger of collapse Pond repair A used pond may require some repair as a result of: The banks collapsing to the bottom and accumulating as mud Some fish that dig up the pond banks and dykes, causing leakages Roots of trees growing bigger and causing cracks through pond dykes Pond repairs therefore, include: Building back the 1 collapsed pond banks and re-shaping the pond using the firm soils from the bottom. Sealing off any leakages After all these repairs the pond is prepared for stocking. The process follows the steps outlined as for new ponds: Liming, fertilizing, fixing inlets and outlets and filling the pond with water. In case of used ponds, however, the lime also helps to kill off germs and eggs or fry from previous harvests. The pond is filled with water through the inlet pipes. The screens prevent entiry of wild fish. The pond is left to stay with full for at least two weeks before stocking. During this period sufficient quantities of natural food organisms develop (see figure below). A fertilized pond is green. The green indicates the tiny green plants suitable particularly for Nile tilapia "Kibaati". In addition to the green plants, the pond water also becomes rich with small animals that are good food for fry. These are the most suitable food items for fry. Farmers would have to be shown by a technical person how to tell that these organisms are present. The pond is now ready for stocking. But just before stocking, the pond should be fished through with a net twice or three times. This is done to remove any wild fish, frogs or any other animal that may have entered the pond while it was filled with water so that it is free for stocking. COLLECTION, GOOD HANDLING, PACKAGING, TRANSPORTATION AND STOCKING OF FRY There are a number of steps to be followed during stocking of a fishpond. These steps take time (up to a month) and a schedule needs to be drawn to save time.

8 The following sequence of activities should be followed. a) Identifying the fry producer with the fry required. The farmer finds out which nearest fry producer has the right type, size and quantity of fry. If there are many fry producers, which one offers the best price, remember to consider the cost of transportation.it is advisable to keep a list of telephone numbers of as many fry producers as possible. This will always available at the office of the Commissioner for Fisheries or the Head of Aquaculture Units, Department of Fisheries Resources Entebbe. ( See appendix i) The farmer should ring and find out the most suitable fry producer. Should there be many fry producers with the right type and size of fry, the farmer should chose the nearest one to cut down on the cost of transportation. b) Making an appointment with fry producer The farmer should make a clear appointment with the fry producer, detailing the number of fry required, type of fish, size of fry and agree the date for collection.the following steps are followed collecting fry for stocking. The farmer should find out from the nearest fry producers who will be having fry by the time the pond is ready. Find this out at least three weeks in advance. The farmer tells the fry producer exactly when he/she will need the fry. iii. The farmer continues to prepare the pond The farmer should finally confirm the availability and agree with the fry producer the date for collection at least five days in advance. The confirmation is necessary because the fry producer could have had another buyer and sold off the fry. The five days are necessary to look for an alternative fry supplier in case the original fry supplier sold off his fry. Fry is collected promptly as agreed. Changing the program to collect the fry at last minute should be avoided at all cost. The fry producer will have removed the fry from the pond intended for that farmers and a lot of the fry may die if not taken as arranged. c) Preparing containers (packaging materials) and means of transport The farmer prepares the containers (packaging materials) for the fry and appropriate transport. The type of container for carrying the fry and the kind of transport to be used depends on: The number of fry to be carried The distance to be traveled The table (table 1) below shows the types of containers and means of transport commonly used in transporting fry. Table 1 Types of container used and number of fry that can be transported. Fry number Distance Suitable container Means of transport Up to 2,000 Less than 1 km Open buckets Jerry cans Polythene bags with air Foot, bicycle, motor cycle (see figure 3.10)

9 Up to 2,000 3km - 20km Jerry cans, polythene bags with air Bicycle, motor cycle, taxi, bus (see figure 3.11) 2,000 to 10,000 Beyond 50km Jerry cans, polythene bags with oxygen Motor cycle, taxi, bus (see figure 3.11) More than 50,000 More than 50km PVC tanks with constant oxygen Truck Note: The Catfish fry does not need pumping fresh air into the container. They come to the water surface and breathe in dry air. A few fry, a short distance; An open bucket is suitable for fry up to 2,000 to be taken to nearby ponds, less than 1 km ( see figure 1) A few fry, a long distance: For a distance up to 1 km and beyond (see figure 2 and 2 ) 1) Farmer carrying fry in bucket to a nearby pond, farmer carrying fish in jerry cans on a "boda boda" to some distant village 2) Farmer carrying fish in jerry can on the head or shoulders on foot for a pond in the next village 2 ) Farmer packing jerry cans and plastic bags of fry into the back of Pick-up. It is wrong to load jerry cans or plastic bags on top of a bus, exposed to direct sunshine. If the only available transport is a bus, put the jerry cans of fry inside the bus in the corridor

10 Packing fry in polythene bags 1. The polythene bags are made from a polythene tube of 500 gauge. 2. The tubes vary in width but commonly they are about 1 1/2 feet wide when laid flat. They are sold in some hardware shops, displayed as rolls but the farmer can buy in metres. In Kampala they are found in Owino market the section selling polythene sheets and bags. 3. The tube is cut into 3 feet long pieces. One end is twisted and tied very tight using small strips cut from an old bicycle tubes to make a bag. 4. The bag is held vertically upright with the open end up. It is filled with water up to half its length. The same water in the nursing pond or tank is used to avoid causing shock to the fry. 5. If different source of water is used, this water should be mixed slowly with the water containing the fry to bring it to the same warmth before fry is transferred into the bag. 6. Sudden transfer of fry into water different in warmth from the water containing the fry will shock the fry and cause sudden death. 7. The treated tap water used at home for drinking should not be used for packing fry. The chemicals used kill fry. 8. The right number of fry as given in the table above is transferred into the bag. The fry must be counted to get accurate number. 9. The mouth of the poly bags is closed, trapping sufficient amount of airs. The mouth is then twisted tightly until the air pressure makes the bag firm and it can stand without collapsing. 10. For fry that is to be transported a long distance, oxygen can be pumped from an oxygen cylinder into the bags instead of just air. The clear transparent bags are better because they allow the fry inside to be seen. Packing fry in poly bags Place the bag in a horizontal rather than vertical position during transportation. In this way a wider surface area is available for air exchange with the water for the fry (see figure below).

11 Keep the bags in horizontal position The number of fry per volume of water used in the package is given in the table below. Volume of water in package (litres) Number of fry in package The bag or bags can then be placed in larger boxes made from cardboards. The inside of the cardboard should be inspected to ensure it has no sharp pins. The pins will prick the bags and the water flows out 12. In case of many bags, avoid piling many bags on top of each other. The bags at the bottom may burst because of the pressure exerted by the bags on top. 13. It is convenient to pack separately the fry for stocking in different ponds. Bag is opened for a particular pond instead of opening many bags and counting the fry. This saves the time during stocking and avoids making the fry exhausted. Packaging fry in jerry cans 1. The jerry can for carrying fry must be very clean. If new, they must not have contained oil or any chemical. 2. Oils can clog the gills of fry and make breathing difficult and can kill the fry. 3. Jerry cans that have contained oils, paraffin, diesel, or any other substance should be washed with soap repeatedly until all traces of smell are finished before use for carrying fry. Better still do not jerry cans. 4. A rectangular opening (about 3x5 inches) is cut at three sides, leaving it held by the fourth side as a flap. The hole is used to ease packing the fry into the jerry can and it also eases air exchange. 5. The jerry can is filled with good water up to 2/3 its height, leaving the other 1/3 containing air.

12 Illustration of jerry cans for carrying fry 6. The same water as that in which the fry had been conditioned should be used. If another source of water is used, the new water must be first mixed with some of the water in which the fry had been nursed to equalize their temperatures and avoid shocking the fry. 7. The selected fry is then counted and put into the jerry can through the cut hole. When packed this way, one jerry can contain up to 200 tilapia and Carp fry. Fry can be transported using jerry cans for a distance of not greater than 200km. Beyond this distance the number of fry should be reduced slightly' 8. The same jerry can take 300 Clarias ("Mmale") fry. The "mmale fry is able to breathe dry air directly from the space while Tilapia and Carp fry only extracts air dissolved in the water. Using larger containers 1. Larger containers, such as plastic tanks, are used to transport a large number of fry, as shown in table The most commonly used are the Crest tanks volumes 300 to 500 litres (see figure 1.18). It is difficult to handle fry in tanks much larger than this size range. 3. Metallic tanks should be discouraged because they may heat up on a hot day. 4. The tanks with larger mouths are better than those with smaller mouths. They make it easier to put the fry in and taking the fry out, it also eases the exchange of water during transportation. Illustration of crest tanks for carrying fry 5. The water should be the same water that had been used to nurse the fry. Or the new water should first be mixed with the old water before fry is introduced. 6. The tank must be filled up to 2/3 their height, the top 1/3 being left to allow air exchange. The prepared fry is counted and packed into the tanks. 7. The maximum number of fry that can be safely carried by the different tanks sizes is given in table 3.3. In each case the number of fry of the Catfish is higher than that of Tilapia and Carp.

13 The number of fry of different fish species that can be carried in tanks of different size (liters) Tank size (litres) Maximum number of Tilapia fry Maximum number of Carp fry Maximum number of Catfish fry ,000 1,000 1, ,000 2,000 3, ,000 3,000 6, ,000 5,000 10, For shorter distances that take up to two hours, the air in the space above the water is adequate for the fry. 9. For distances that take longer than two hours, and oxygen cylinder should be fixed to provide a continuously supply oxygen throughout the journey. 10. For Clarias ("mamle") fry, the oxygen cylinder is not required. The fry breathes dry air directly from the space above the water. Care for fry on transit 1. Fry is a living and delicate thing. It should not be handled like goods. If not handled well it may die before reaching the pond for stocking. 2. The trip for collecting fry should not be combined with other activities that may cause delays, if it is not avoidable, then the other activities must be completed the fry is loaded last. 3. Young fish cannot tolerate starvation for long, it dies easily. Therefore, ensure that there is sufficient food in the pond before collecting the fry to stock:- 4. The source of fry may be far and transportation costs high and yet ample time must be given to the fry producer to prepare the fry for collection. Therefore, it is important to make an appointment with the fry producer before collection to avoid disappointment or delay. d) Fry Transportation and pond stocking Preparation of fry for collection is the responsibility of the fry producer. But the farmer needs to know the process because he/she will lose the fry if not prepared well. 1. The fry to be transported the following day should be harvested from the pond a day before. During harvesting fry gets tired and needs to rest for at least a day before it is transported. 2. The fry to be transported should not be fed for that day. It should be allowed to empty its gut and remain with empty gut throughout the journey. 3. When the gut has food, the fry will be emptying its gut into the containers and the excreta will pollute the water and kill the fry. If the farmer waited to complete pond preparation, and to fill with water and then start looking for fry a lot of time can be wasted The following schedule of these activities can help save time Tables below showing the schedule for stocking fish pond can be of great help. The following two tables summarize the arrangements for collecting and stocking the fry.

14 Table of activities for stocking your pond with fry Activity number Activity 1 Find out from a fry producer when fry can be available then allow 3 weeks to prepare for stocking 2 Drain pond and allow to dry (if had been with fish) 3 Repair pond bottom, banks and dyke and water channels 4 Lime then enter a little water to the depth of 2 inches at inlet end 5 Fix screens on outlet and inlets 6 Add manure 7 Fill pond with water to maximum level 8 Allow pond to become green (at least 5 days) 9 Confirm date for collecting fry, leaving at least 5 days for preparation 10 Collect fry and stock A schedule of activities for stocking a fish pond It takes normally a minimum of 2 1/2 weeks from completing pond construction or harvesting to stocking with new fry. Note: Do not stock fry in the pond to starve to death. When fish is stocked in a pond that has not yet developed enough natural food, the fish may starve and die. The pond to be stocked must be prepared to develop sufficient quantity of natural food for the fry before stocking. A summary of steps followed in fry collection, transportation and stocking Preparation of the pond to be stocked Making an appointment with the fry producer (agreeing date for collection, type and number of fish, items required) Prepare packaging materials

15 Packaging fry Care during transit Introducing (stocking) the fry into the new pond Inspect stocked pond for any dead fry for at least three days after stocking If many fry die, arrange for restocking e) Preparation of fry for collection The farmer should collect the fry promptly according to the appointment. Failure to collect the fry on the date agreed may result in some fry dying. For this reason, fry producers may demand advance payment, a percentage cost of the fry.the fry producer harvests the fry and prepares it for collection Fry should be collected on appointment with the fry producer, specifying date, time, fish type and quantity of fry, to allow adequate time for preparation. The main activities from collecting fry to stocking fry in the pond and the time required are outlined in this sector. Fry must be harvested from the nursery pond and allowed to rest for one full day before transporting. During rest the fry should not be fed at all. Therefore, do not keep fry resting for more than 3 days otherwise it starves. The reasons for this are: The rest period allows the fry producers to sort out the fry that was injured or exhausted to die out. The survivors are those that are strong and healthy enough for sale The rest period also allows the fry to empty their gut before transportation because fry is not fed. Packaging fry for transportation The type of containers required for carrying fry and the type of transport depend mainly on:- The distance to be traveled The quantity of fry to be carried (see figure below) The fry must be counted ' Fry is packaged and transported in appropriate containers depending on the distance to be traveled and the quantity of fry. Caution: There is common tendency to combine the trip to collect seed with other business, especially for distant farmers to cut costs. Should this be the arrangement, then every other business must be done first and the fry the fry is picked finally for onward travel. The living fry must not be delayed on the way.

16 When fry are transported with full gut, they release their excreta into the container during the journey. The excreta, mainly ammonia, is poisonous and may cause mass death of the fry along the way. Care for fry during transportation As much as possible avoid transporting fry during very hot hours of day. Very late evening or night are the most ideal times. Do not expose fry in direct sunlight The rains help to keep the fry cool Avoid stopping on the way. But if you must stop, keep it very short and park the fry und«shade. Stop at intervals during travel to inspect the fry in the containers. Fry may get exhausted, some may die and dissolved oxygen may be depleted. The simplest sign that the fry is in need of fresh air is when most of the fry come to the top of the water in the container and start gulping for air (see figure 3.20). A picture of fish gulping for air At this point the water in the containers need to be changed (completely or partial replacement). Find the nearest stream with water that you have no reason to suspect that it is polluted or dirty. Stop at the stream and open the containers. Carefully reduce the water in the containers (by siphoning or pouring out, depending on the type of container). Take care not to pour out the fry. As water is pouring out, add the stream water very slowly to avoid shocking the fry. The temperatures of the water carrying fry and the stream water may be very different. When the replacement is sudden, the sudden change in temperature may kill the fry. Any dead fry must be removed immediately from the container to avoid rotting and polluting the water. Note: The steps outlined above shows the need to have certain basic containers during fry transportation. These include: Buckets with handles for collecting water, Extra polythene bags, in case one develops a leakage. Introducing the fry into the pond If not done properly the fry may arrive at the pond having traveled a long distance and then die at the pond edge. What usually kills fry at stocking is the sudden introduction into the new pond whose water temperature may be very different from the water that the fry came in. The fry must be introduced very slowly to allow it to get used to the new conditions. This is done as follows:

17 Get the fry for each pond into a container. Fry to be stocked must be counted. Get some water from the pond to be stocked and slowly add into the container with the fry and mix the waters slowly until about 50% of the water with the fry has been replaced (see figure below). Place the container with the fry in the water at the edge of the pond. Tilt the container slowly into the pond water until the two waters are in contact. Slowly pour the container water with the fry into the pond. Watch that the fry swims into the new water voluntarily. The stocking process will last as long as 20min for a small pond. Releasing fry into the pond Some fry may become too exhausted during transportation and may not recover fully. To ensure the exact number of fry that was successfully stocked, the farmer should inspect the pond for any fry that may die. The number of fry that died at stocking is recorded each day for up to three days. The inspection recording of the dead fry should be done very early before birds come and pick out the dead fry. The total number of fry that died at stocking is added up and subtracted from the total fry that was collected. If the number of fry that died does not exceed 20%, the growing of the remaining stock continues. If the number exceeds 20%, a trip is made to collect and replace the dead number. The fry should be collected from the same farmer and same stock to avoid mixing fry of different age groups. For the moment a stocking rate of 2 fish per m 2 of pond area is recommended for all the three commonly farmed fish types (Nile tilapia, Carp and Catfish). For the more intensive production systems, where the farmer is able to feed intensively, higher stocking rates are calculated for the farmer on a case-by-case basis. Seek expert advice from Kajjansi or a qualified service provider. Note: Because of the elaborate steps taken during transporting and stocking fish fry, it is strongly recommended that, if more than one pond is to be stocked, fry for each pond should be packed separately to minimize effects of handling. Stocking becomes a lot easier. Recommendations Avoid collecting fry from the wild (lakes, rivers/streams or swamps). Fry should be purchased from well-known and certified fry producers. These fry producers keeps production records make it easier to follow up sources of poor fry. Table below gives the disadvantages and loss of benefits that may arise from collecting fry from the wild.

18 Advantages & disadvantages of using fish hatcheries compared to wild sources. Source of seed Fish Hatcheries Wild sources Advantages 1. Lower risk of obtaining fish of the wrong species. 2. Seed supply not influenced by seasons. 3. Quality assurance (size, age, species, health). 4. In case of problems one can follow up source. 1. Sources may be closer to farmers, hence often more accessible 2. May be cheaper Disadvantages 5. Greater guarantee of obtaining farmers required number for stocking of required quality 1. Sources often far for the majority of farmers which increases transport costs for farmers. 2. Seed costs may be higher 1. Supply influenced by seasons 2. Difficult to obtain larger numbers of the same quality at the time a farmer requires them. 3. In order to collect required numbers, fish often collected and stored over a period of time by fishermen which is more stressful for fish. This results into heavy losses (high death rates) at stocking. 4. Cannot guarantee age of fish 5. it is illegal to fish undersized fish from the wild. Appendix I The list and contact addresses of certified fry producers as at 2004 Name of Establishment Species available Location/address Contact number Aquaculture Research and Development centre Sunfish Farm Ltd Nile tilapia Mirro Carp African catfish Ningu Nile tilapia Mirror carp African catfish Kajjansi TC P.O. Box 530 Kampala Kajjansi TC P.O. Box Kampala Aquafarm Nile tilapia Wakiso District Bukinga Fry centre Nile tilapia Kabale Abi fry centre Nile tilapia Arua Note: This list may keep changing with time as informed by Fisheries Department Entebbe

19 The Executive Director NAADS Secretariat P.O. Box Kampala Tel: , Fax: