The Effects of Temperature on Feeding in Snakes

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The Effects of Temperature on Feeding in Snakes

• Andrew J. Clark
• October 13, 2004
• Eco/Evo 208

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Primary References

• Ayers, D. Y. and Shine, R. 1997. Thermal
  influences on foraging ability body size,
  posture and cooling rate of an ambush predator,
  the python Morelia spilota. Functional Ecology.
  11 342-347.
• Greenwald, O. E. 1974. Thermal dependence of
  striking and prey capture by gopher snakes.
  Copeia. 1974 141-148.

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Ayers and Shine, 1997The Subject

• Diamond Pythons, Morelia spilota
• New South Wales
• a relatively cool environment
• Pythonidae

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Ayers and Shine, 1997 Hypothesis

• SA/vol ratio is decreased by large size tight
  coiling
• Retards cooling rate
• Increases time needed for detecting and capturing
  prey

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Ayers and Shine, 1997Measurements

• Cooling Rates
• 3 body sizes
• hatchlings, juveniles, adults
• 2 postures
• outstretched coiled

• Tongue-Flick Cycle Rates
• 3 body sizes
• hatchlings, juveniles, adults
• 3 temperature settings
• 10ºC, 20ºC, 30ºC

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Ayers and Shine, 1997Results

• Cooling Rates
• equilibration times thermal temperature
  constants were significantly different among size
  groups
• Thermal T Constant (t) Q x R

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Ayers Shine, 1997Results

• Equilibration Times

• Thermal Temperature Constants

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Ayers and Shine, 1997Results

• Tongue-Flick Cycle Rates
• increased rapidly at higher temperatures

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Greenwald, 1974The Subject

• Sonora Gopher Snake, Pituophis catenifer affinis
• SW USA and Mexico
• Colubridae

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Greenwald, 1974

• Measured strike speed and success of strike
• At different body temperatures
• 18ºC, 22ºC, 27ºC, 33ºC

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Greenwald, 1974Results

• Mean velocity
• Maximum velocity
• Prey capture success

Increased with increasing body temperatures in
the range tested
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Greenwald, 1974Results Mean Velocity
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Greenwald, 1974Results Maximum Velocity
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Greenwald, 1974Results Prey Capture Success
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