. The Canadian field-naturalist. Natural history. 2001 Notes 183. Figure 1. Chelydra serpentina from Pontiac County, Quebec, with mutilated anterior fore- limbs. The absence of previous reports of limb mutilation in Snapping Turtles is not surprising, as the species has a number of physical and behavioural character- istics which serve to dissuade potential predators. Wild adult male Chelydra can reach a maximum carapace length of 494 mm and weigh as much as 34 kg (Conant and Collins 1991: 41). When harassed, they can also exude a foul smelling musk from glands located on the shell bridge (Car
. The Canadian field-naturalist. Natural history. 2001 Notes 183. Figure 1. Chelydra serpentina from Pontiac County, Quebec, with mutilated anterior fore- limbs. The absence of previous reports of limb mutilation in Snapping Turtles is not surprising, as the species has a number of physical and behavioural character- istics which serve to dissuade potential predators. Wild adult male Chelydra can reach a maximum carapace length of 494 mm and weigh as much as 34 kg (Conant and Collins 1991: 41). When harassed, they can also exude a foul smelling musk from glands located on the shell bridge (Carr 1952: 65). Moreover, a Snapping Turtle will tilt and lower the portion of its shell under attack, while turning to face its aggressor (Dodd and Brodie 1975). Lastly, the Snapping Turtle has a distinctly belligerent nature which it backs up by lightning quick strikes at speeds exceeding 78 ms (Lauder and Prendergast 1992). Therefore, it is not surprising that encounters between Raccoons and nesting female Snapping Turtles do not lead to predation attempts on the tur- tles (Congdon et al. 1987). Known causes of limb loss in turtles include attacks by mammalian predators (, Harding 1985) and agricultural mowers (Ernst 1976; Tuttle 1996). It is, however, improbable that an adult Raccoon could gnaw off both anterior limbs of a fully alert adult Snapping Turtle. Consequently, it is much more like- ly that the attack occurred when the turtle was small and relatively defenseless (, Robinson 1989; Walley 1993), or while it was in a state of torpor dur- ing hibernation (, Brooks et al. 1991). Due to the remote location of the Pontiac site, it is unlikely that an agricultural mower was the cause of the amputa- tions. However, limb loss due to agricultural mowers or predation cannot be ruled out for the BCNWA turtle. Brooks (personal communication) reports that the observed frequency of limb loss in Chelydra ser- pentina at his Algonquin Park, Hamilton Harbour, and Lake Erie
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