36 JUNE 2013 • WORLD AQUACULTURE • WWW.WAS.ORG Freshwater crayfish has been traditionally consumed in Europe for centuries. Freshwater crayfish recipes have been recorded by Caelius Apicius in his work De re culinaria (3rd century AD) (Lagerqivst and Nathorst-Boos 1980). In Scandinavia, there are written reports from the 16th century about the culinary importance of freshwater crayfish to the Swedish royal family (Abrahamsson 1969), while in Central Europe the Emperor Maximilian I (of the Hapsburg Empire) and the Archbishops of Salzburg were giving written orders on crayfish catching (Ackefors and Lindqvist 1994). Between 1853 and 1879, more than 5 million freshwater crayfish were consumed annually in the wider Paris area (Smolian 1926 from Ackefors and Lindqvist 1994). Consequently the meticulous work on crayfish biology (Huxley 1880) and histology (Haeckel 1857) in the nineteenth century is not surprising. The industrial revolution in the middle of the 19th and the beginning of the 20th century led to the acidification of natural water reservoirs with negative effect on survival of then existing populations of wild noble crayfish (Astacus astacus Linnaeus 1758). Subsequently the remaining “healthy” populations were overfished, while crayfish plague (Aphanomyces astaci) further decimated remaining stocks of the species (Arrignon 1990, Westman et al. 1990). During the 1960s and 1970s, Europe imported the North American signal crayfish (Pacifastacus leniusculus Dana), which is resistant to the plague pathogen as far as symptoms are concerned. However the signal crayfish is a plague carrier and therefore its management in natural reservoirs should be carefully considered (Ackefors et al. 1989). In Greece during the early 1980s, crayfish plague started to spread in noble crayfish populations of the Kalamas River (Northwestern Greece, Epirus County) and decimated most of the existing healthy populations in the adjacent Louros River and the nearby lake of the city of Ioannina (Theocharis 1986). Some “Greek” noble crayfish populations have now managed The Potential of Freshwater Crayfish Culture in Greece Panagiotis A. Pantazis to recover from the continuous environmental disturbances driven by human activities (domestic wastewater, pesticides, insecticides, industrial pollution). In addition to the noble crayfish, other freshwater crayfish species exist in Greece, such as Austropotamobius torrentium, Astacus leptodactylus and Pacifastacus leniusculus. All species are found in 20 of the 53 prefectures in Greece and form isolated populations in relatively pristine water bodies (Koutrakis et al. 2007). Annual landings of freshwater crayfish in Greek markets are not exactly known, but formerly accounted for 4-5 t/yr. However, because of recent restrictions imposed by the Hellenic Ministry of Agriculture, landings have dropped to 0.5-1 t/yr. Europe experiences a deficit of 2000-2500 t/yr in crayfish production, leading to imports from Russia, China, the USA and Turkey. As a result, the potential for freshwater crayfish aquaculture in Greece is promising. The Laboratory of Ichthyology, Aquatic Fauna & Fish Diseases, Faculty of Veterinary Sciences of the University of Thessaly is situated by the Karditsa city in the Thessaly County. Lake Plastira, located to the west of the city of Karditsa (39° 14’ 39.19” N, 21° 44’ 20.49” E – Fig.1) covers an area of 25 km2, has a maximum depth of 60 m and a capacity of 400 million m3 (Stefanidis 2001). Lake Plastira receives water from the Tavropos River and a number of smaller adjacent streams and torrents (Karitsiotis, Megalo Potami) and the aquifer of its catchment basin is connected to a number of streams and reservoirs of Karditsa Prefecture. Locals in Karditsa Prefecture report that many of those water reservoirs formerly supported noble crayfish populations and that some of those populations continue to exist. However this has not been confirmed based on personal observations and communication with local fishermen and local authorities. The Laboratory of Ichthyology, Aquatic Fauna and FIGURE 1. Location of the Plastira Lake situated to the west of the city of Karditsa, Central Greece.
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