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
- Cite this article as:
- Bishop, C.A., Brown, G.P., Brooks, R.J. et al. Arch. Environ. Contam. Toxicol. (1994) 27: 82. doi:10.1007/BF00203891
Statistical analyses were used to determine relationships between body size, clutch size and mass, and relative clutch mass and levels of organochlorine pesticides and seven polychlorinated biphenyl congeners in the eggs of adult female common snapping turtles (Chelydra serpentina serpentina). No significant correlations were found between body size (body mass, carapace length, carapace width, plastron length) and lipid normalized concentrations of p,p′-DDE, mirex, dieldrin, and polychlorinated biphenyl (PCB) congeners (IUPAC): #52, #105, #118, #138, #153, #180, #194, and the sum concentration of those congeners. Small sample 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 predictors of the level of contaminants in snapping turtle eggs and that adjustment for those parameters would not reduce variation in contaminant levels among clutches. Other variables such as individual food preferences and/or foraging activities are more likely to cause variation in chemical concentrations among clutches of eggs within a population. In order to reduce interclutch variation in contaminant levels to 38.6–55.9% in snapping turtles, sample sizes of at least 15 clutches per site are recommended.