ORGANOCHLORINE CONTAMINANT CONCENTRATIONS IN EGGS AND THEIR RELATIONSHIP TO BODY-SIZE, AND CLUTCH CHARACTERISTICS OF THE FEMALE COMMON SNAPPING TURTLE (CHELYDRA-SERPENTINA SERPENTINA) IN LAKE-ONTARIO, CANADA

Statistical analyses were used to determine relationships between body size, clutch size and mass, and relative clutch mass and levels of or ganochlorine pesticides and seven polychlorinated biphenyl congeners i n the eggs of adult female common snapping turtles (Chelydra serpentin a serpentina). No significant correlations were found between body siz e (body mass, carapace length, carapace width, plastron length) and li pid normalized concentrations of p,p'-DDE, mirex, dieldrin, and polych lorinated biphenyl (PCB) congeners (IUPAC): #52, #105, #118, #138, #15 3, #180, #194, and the sum concentration of those congeners. Small sam ple size and clumping of data around the mode of the body size values prevented inferences of nonlinear relationships. It was concluded that body size and clutch characteristics are not strong or reliable predi ctors of the level of contaminants in snapping turtle eggs and that ad justment for those parameters would not reduce variation in contaminan t levels among clutches. Other variables such as individual food prefe rences and/or foraging activities are more likely to cause variation i n chemical concentrations among clutches of eggs within a population. In order to reduce inter-clutch variation in contaminant levels to 38. 6-55.9% in snapping turtles, sample sizes of at least 15 clutches per site are recommended.