Pompano is the one of the most highly desired brakishwater fishes. It has an excellent flavour and its monetary value is high. Several species of fishes in various part of the world have the common name Pompano. We restrict this name to the species of genus Trachinotus of the family Carangidae.
CLASSIFICATION
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Perciformes
Family: Carangidae
Genus: Trachinotus
Species: mookalee
BIOLOGY OF POMPANO
Pompano, (Trachinotus), any of several marine fishes of the family Carangidae (order Perciformes). Pompanos, some of which are highly prized as food, are deep-bodied, toothless fishes with small scales, a narrow tail base, and a forked tail. They are usually silvery and are found along shores in warm waters throughout the world. The Florida, or common, pompano (T. carolinus), considered the tastiest, is a valued commercial food fish of the American Atlantic and Gulf coasts and grows to a length of about 45 cm (18 inches) and weight of 1 kg (2 pounds).
In nature; young Pompano feed relatively on benthic and pelagic invertebrates such as amphipods, bivalve mollusk, crab larvae,copepod and isopods; at times they feed heavily on young of other fishes particularly clupieds. The adult appear to have similar food preferences. In captivity; the young grow well on a diet of mixed ground shrimp, fish and frozen brine shrimp. Fishmeal may be an adequate diet, Larger fish thrive on ground or chopped fish; they can also be feed ground scrap fish from trawl catches, chicken feed and tankage from slaughter house.
GROWTH RATE
Young Pompano in nature probably grow about 1/4 to 1/2 inches per month
Fish in captivity has been raised from a length of about one inch to over 10 inches and a weight if about one pound within an year
TOLERENCE
The juveniles and adult Pompanos tolerate a wide range of environmental conditions including low levels of dissolved oxygen and salinities ranging from 0 -50 ppt
FECUNDITY
It’s fecundity has been estimated to range from 133000 – 800000 per season
CULTURE AND SEED PRODUCTION OF POMPANO
BROODSTOCK PROCUREMENT
Pompano can be collected throughout the year from the Estuarine waters. Broodstock can be collected by using Trammel nets, Gill nets, Hooks & Line. Gill nets are most efficient way to collect large numbers of adult Pompanos. Pompanos collected offshore can be held for a short time in the live wells on boats with the use of liquid Oxygen. Then they are transported to shore and transferred to tank or ponds to be used for spawning. Juveniles can be collected from wild and reared in captivity until they reach sexual maturity. Viable broodstock also can be obtained from hatchery reared Pompano.
SPAWNING BEHAVIOUR:
There is limited information in the spawning behaviour of captive Pompano. Captured Pompano have been induced to spawn year round using hormone injections coupled with photoperiod and temperature manipulation [photothermal manipulation] . Fishmeal may be an adequate diet of them. Spawning was induced with hormone injections [Human Chorionic Gonadotropin-HCG ] based on body weight coupled with photothermal manipulation to produce eggs in both wild- caught and hatchery reared Pompano. For this fish were collected in a smaller tank and anazthetized using tricainemethanesulfonate[MS-222]. A cannula tube was used to check the state of gonadal maturation.
Both males and females given a single intramuscular injection about halfway between the lateral line and first dorsal fin spine. Females with vitellogenic and/or post vitellogenic stage oocytes were injected with a single dose of HCG at 1000 IU/kg body weight. Male received a single dose of HCG at 500 IU/Kg body weight. Spawning occurs 40 to 48 hours after the injection, followed by small, less viable spawn up to 96 hours post injection. In general the female pompano will produce 100000 fertilizable eggs per pound of total body weight.From seven documented induced spawning for wild caught and hatchery – reared Pompano a total of 5.3 million eggs were collected.
POMPANO FARMING
In view of the limited knowledge of biological requirements and tolerences of Pompano the following recommendations should be tentative. After the fry are netted on the beach, they should be moved carefully and rapidly to a carrying tank and transferred as quickly as possible to their first growing pond or aquarium. Use of compressed oxygen or air may be needed to transport the fry long distances. Only one species of Trachinotus should be stocked; by popular preference, it should be common Pompano – Trachinotus mookalee . Larvae and fry of other fishes and invertebrates that could compete with the Pompano for food and space should be excluded from the pond if possible.
The young Pompano should be fed several times each day. We have been told that the very young may require a daily ration of about 1/10 of their body weight. A finely ground food of adult brine shrimp, fish filets and whole shrimp has proved satisfactory for young Pompano in the first two months or so after capture. Ground shrimp heads and ground or cut whole scrap fish are good when the Pompanos are 3 to 4 inches long and larger. Fish meal suffices for fish of all sizes, but small pellets of fish meal are more economical for larger fish. Newly caught fry should be placed in an aquarium or small pond for a few days or weeks for observation of food requirements. More efficient food of offered and culling of sickly or diseased fish and of other fish species can be accomplished. Young Pompano should not be retained too long in aquaria or small ponds because it has been demonstrated that growth of fish often slows when they are crowded. Pompano probably grow better at a nearly constant temperature. Extremes of temperature especially below about 50F are usually injurious or fatal.
Among the problem that need to be investigated are the following;
1.Optimum salinity and temperature for holding the Pompano.
2. Diseases of Pompano which could affect production.
3. Amounts and kinds of food which should be fed to Pompano of various sizes.
4. Optimum sizes of ponds and stocking rates.
5. Important biological factors such as growth rates and life span.
In the United States, the market for pompano prefers them to be whole and fresh iced.
Only wild caught pompano exceeding 2 pounds in size are used for fillet market.
Due to the nature of the market demands the pompano farm must know what customers they are supplying on what days in order to keep fresh, low shelf life, product flowing to the markets. As of this time there is no value added processing of either wild or farmed pompano . Elements that determine pond productivity are water quality, water salinity, oxygen, temperature, food supply, avian predation, and jumping out of pond. But the production losses due to the above mentioned parameters do not cause losses in excess of 10%. Therefore, the pond is originally stocked with 10% more fry or 5,500 per pond.
LARVAL CULTURE
Fertilized eggs are buoyant, transparent about 1mm in diameter and have a single oil droplet. Newly hatched larvae measure approximately 2mm standard length [SL] have little or no pigmentation, lack of functional mouth and have a large yolk sac with a single oil globule. At 7days post hatch [DPH] and a temperature of 28 degree Celsius, the temperature is reduced, the yolk is fully absorbed, the eyes are fully pigmented and the mouth is fully formed. Transformation from larval stage to juveniles begins approximately 24 DPH at which time scales develop and pigmentation appears over the lateral surfaces of the body. Fertilized eggs resulted from hormone induced natural spawns of wild caught or F1 Pompano on the day of spawning, the fertilized egg were stocked in three separate rearing tanks at densities of 50 to 75 eggs/ L and incubated at 26 degree Celsius. Hatching began 24 hours post fertilization and hatch rates were estimated at 75.5 percent. Mean larval length at hatch was 2.3mm SL.
Rotifers, Artemia etc are the different forms of diet that feeds the Pompano larvae at different stages of development with different quantities.The concentration of feed in the larval rearing tank should be check twice daily. And additional feeds are added to the tank volumetrically to maintain the desired number of individuals.
DISEASES
The broodstock and juveniles collected from the wild can carry parasites and should quarantined and treated for several weeks before they are introduced into any culture systems. Amylodinium is a particular problems for both juveniles and adults in recirculating systems. This parasite has a high reproductive rates and many life stages and tend to be quiet resilient to treatment. Amylodinioum is typically found on the gills and can cause high mortality rates if left untreated. Individuals infected this parasite often show coughing or flashing behaviour.
Pompanos have relatively high demands in local and regional seafood markets and it is highly priced by recreational fishers also. The juveniles and adult Pompanos tolerate a wide range of environmental conditions including low levels of dissolved oxygen and salinities ranging from 0 -50 ppt.
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