Data from: The effects of temperature on the defensive strikes of rattlesnakes

Movements of ectotherms are constrained by their body temperature owing to
the effects of temperature on muscle physiology. As physical performance
often affects the outcome of predator–prey interactions, environmental
temperature can influence the ability of ectotherms to capture prey and/or
defend themselves against predators. However, previous research on the
kinematics of ectotherms suggests that some species may use elastic
storage mechanisms when attacking or defending, thereby mitigating the
effects of sub-optimal temperature. Rattlesnakes (Crotalus spp.) are a
speciose group of ectothermic viperid snakes that rely on crypsis,
rattling and striking to deter predators. We examined the influence of
body temperature on the behavior and kinematics of two rattlesnake species
(Crotalus oreganus helleri and Crotalus scutulatus) when defensively
striking towards a threatening stimulus. We recorded defensive strikes at
body temperatures ranging from 15–35°C.We found that strike speed and
speed of mouth gaping during the strike were positively correlated with
temperature. We also found a marginal effect of temperature on the
probability of striking, latency to strike and strike outcome. Overall,
warmer snakes are more likely to strike, strike faster, open their mouth
faster and reach maximum gape earlier than colder snakes. However, the
effects of temperature were less than would be expected for purely
muscle-driven movements. Our results suggest that, although rattlesnakes
are at a greater risk of predation at colder body temperatures, their
decrease in strike performance may be mitigated to some extent by
employing mechanisms in addition to skeletal muscle contraction (e.g.
elastic energy storage) to power strikes.