There appears to be some disagreement with regard to the annual trout production figures. According to one source the annual trout production is estimated between 700 and 800 tons derived from 80 producing units in Epirus, each being supplied on a free distribution system with 20 000 fry from a Government hatchery or through imports. This would total 1.6 million fry, and assuming there are no losses in the hatcheries and trout farms throughout the year and the final trout market size weighs between 450 and 500 g, the above production figure is feasible. However, the majority of the hatcheries and fish farms reported occurring heavy losses.
According to Ananiadis (1973), the annual trout production in Epirus amounts to 440 tons derived from 64 fish farms. The total surface area utilized including small natural lakes, is about 54 000 m2, with an average yield of about 8 kg/m2. The gross value of trout production amounts to U.S.$ 487 000. Since no accurate data were made available it is quite possible that annual production fluctuates considerably from year to year. Trout culture activities in Epirus commenced in 1966.
Opportunities were given to visit the following fish farms:
The visit to the Sivas trout farm near Konitsa was very unusual for its problems and feed used. He is attaining excellent production within very limited resources. His earthen ponds are from one half to one metre in depth. Most of the depth is near the minimum figure. This is below average for most fish ponds visited, but he feels the expense is too great to change the structure. The exchange rate and uniformity of flow through the bigger ponds is very poor or low. However, the larger water surface area in relation to the depth affords a good natural aeration of the water. In late November he usually has a mortality of trout. Some apparently dying trout were field checked but showed no signs of disease. Since the autumn season brings falling leaves the coating of decaying leaves in the bottom of the earthen ponds was pointed out. With the already mentioned physical characteristics of the ponds this could mean a complete chemical change in the pond waters and probably is the reason for such mortalities. To eliminate such adverse factors would be very expensive and might cause further complications, such as too hot a pond water in the summer. Thus he is fully utilizing the present farm potential. The rest of the year he has no particular disease problems. His feed does not comprise fresh fish.
The Vsidis trout farm near the Louros hatchery uses the same water as the Government station. The recently built fingerling raceways do not have enough slope to drain and clean well. He was feeding fresh dromitsa (Rutilus sp.) and sardines and complained of frequent disease problems or mortalities. The bottom of the raceways were littered with chopped dromitsa and sardines mixed with an abundance of fish faeces. Clean environment and health usually go together.
The Aghios Georgios Springs, with the rented fish farm was visited during travel in the Arta District. It is a very large spring at a suitable level for cheap and adequate water utilization. Hatchery facilities were above average for private fish farms. The hatchery manager said he had no particular disease problem and did not feed fresh fish.
Three other private farms were visited in the Arta District. The two at Kerassavon are discussed under diseases. The third private trout farm had lost most of its fingerlings earlier in the year. There is an abundant supply of water which seems ideal for trout culture. The farm is at the lower end of a small village with many possible causes of contamination. The farm also feeds fresh dromitsa fish.
A private fish farm near Ioannina City water supply is supposed to have produced 180 tons of trout for market in two oval earth ponds. There are many trout in the head or spring water source which are also fed. The owner claims spring flow being below normal this year and that he has frequent outbreaks of disease. He feeds fresh dromitsa frequently1. There is no way to clean the ponds properly, no practical way to calculate the water volume for a medicated water treatment accurately and no outlet to flush the medicated water after treatment. He will probably continue to be troubled with mortalities.
The Epirus and Edessa areas definitely have numerous ideal trout producing waters. Several of these are quite large with little or no current production. Some of the smaller springs are near maximum capacity but are hampered by poor feed and diseases. The more successful fish farms are not using fresh fish for fish feed and therefore have no disease problems.
The temperatures in these spring waters generally vary from 14°C to 16°C. Such temperatures assure a rapid growth of the small trout to market size with excellent food conversion, provided a balanced disease free diet is available.
There are commercial dry feeds available which are good and do not need refrigeration. However, Hexamitus, a flagellated protozoa of the lower intestine, is common in fish fed only dry feeds. It reduces growth and causes mortality if not treated. In both feeds the fresh water fish ingredients and most salt water fish ingredients are pasteurized to avoid disease problems.
There are several good dry fish feeds prepared by private companies. One is Clark's New Age Fish Feeds at Salt Lake City, Utah, U.S.A. Another is Silver Cup Fish Feeds at Murray Elevators, Utah, U.S.A. It is possible that one or both of these companies would provide a supplement fish food which with the ingredients available in Greece would compose a balanced diet. This should be cheaper than importing a complete pellet like the Dutch feed. Whichever of all dry diets proves best this would also give a standard of performance control to excel in developing a 100 percent Greek fish feed not requiring refrigeration, or instal sufficient refrigeration for the Oregon moist pellet type.
A low temperature dryer which has also low pressure is the basic start in preparing a dry food programme. It produces a higher quality dry product.
Using a prepared diet for broodstock is the most difficult requirement. It is fed over a much longer period and has to produce viable eggs. The Oregon moist pellet has proven adequate here. Others may need supplemental feeding of fresh warm blooded animal byproducts such as liver, spleen, lungs and tripe starting several months before spawning time.
