World Status, Exploitation and Trade - WIDECAST

.INTRODaCTIONAlthough re-colonisation of former nesting beaches, or reinforcement ofdepleted populations, would in principle be expected given significantpowers of dispersal, these phenomena would not in practice be expected totake place over a time span of only a few decades. Late maturity, combinedwith a large element of chance, means that restoration of former nestingcolonies could, in most cases, barely be perceptible in the brief periodduring which marine turtle populations have been receiving scientificattentionTURTLE EXPLOITATIONTurtle products:edibleThe eggs of all species of sea turtle are widely used for food. WhilstHawksbill flesh is consumed in some areas, generally it is not greatlyfavoured; it has been responsible for a number of instances of foodpoisoning, and some fatalities. Green Turtle meat is widely utilised, andcartilage has been sought by luxury markets for the preparation of "turtlesoup" since at least the seventeenth century in Western Europe, andsubsequently in North America also. The term "calipee" is used generallyfor the cartilage lining the plastron (ventral portion of the shell), oftenlight greenish in colour, and "calipash" for the darker cartilaginousportions associated with the carapace (dorsal shell) and vertebral column(Parsons, 1962); sometimes all such cartilage is collectively referred to ascalipee. Nearly half the wet weight of a Green Turtle constitutes edibleprotein, according to figures cited by Hirth (1971). Hirth (1968) statedthat 40-50 % of the body weight of C. mydas formed edible meat. There is awidespread belief in the medicinal properties of turtle oil, and it isparticularly attributed with the ability to cure various bronchialcomplaints.Turtle products:non-edible"Tortoiseshell", referred to as "bekko" in the Japanese trade (now by farthe world's largest consumer of shell), has long been in demand for itsdecorative qualities. It is much thicker than the shell of other species ofturtle and can be carved in single thicknesses or laminated together to formlarger structures. The large plates of the dorsal carapace (usually 13 perturtle) have the greatest value, while those of the plastron are seldomused. The marginal scutes, often referred to as "hooves" or "claws" mayoccasionally be carved into jewellery. The shell of wild C. mydas . which isvery thin, has very little value and has only been extensively used formarquetry. Oil rendered from turtle fat, seemingly from C. mydas more oftenthan E. imbricata , has long been in use as fuel, lubricant and waterproofingagent, and in cosmetics. The demand for turtle skin, which can be tannedinto an attractive leather, has newly-arisen in the last few decades.Certain relevant data concerning individual productivity of turtlecommodities are summarised in Tables 3 and 4.According to Witzell (1983), the amount of shell that can be derived from anadult Hawksbill varies with age and size from 1 to 6 kg, with 3.3 kg beingthe mean of values cited in 12 literature sources. This value presumablyrefers to all of the shell plates, rather than only the dorsal scutes whichare normally marketed. Parsons (1972) stated that a good-sized Hawksbillmay produce 3-4 lb (1.4-1.8 kg) of tortoiseshell. Hornell's (1927)Seychelles data, cited below, are from a region with Hawksbills of22