THE EFFECTS OF SALINITY AND TEMPERATURE ON APPETITE IN THE DIAMONDBACK TERRAPIN MALACLEMYS-TERRAPIN (LATREILLE)

The appetite of saltmarsh diamondback terrapins (Malaclemys terrapin) is extremely large (mean satiation ration on a diet of mussel flesh at 25-degrees-C = 7.2% body weight), some 8-10 times that of closely related freshwater emydid turtles. When held in sea water without access to fresh water the appetite of diamondbacks is gradually depressed, reaching (after 18 days in sea water) 22-54% of the average satiation ration recorded when fresh water is available. Between 20 and 35-degrees-C appetite in Malaclemys is stable (Q10 = 1.1). Between 15 and 20-degrees-C Q10 = 20.7, indicating a shift to a hypometabolic state below 20-degrees-C.