Avoiding the serpent's tooth: predator–prey interactions between free-ranging sidewinder rattlesnakes and desert kangaroo rats

Managing predators: The influence of kangaroo rat antipredator displays on sidewinder rattlesnake hunting behavior

“…Previous studies have reported that foot drumming functions to inform snakes that the displaying kangaroo rat has detected them (Randall & Matocq, ). The detection‐advertisement function of foot drumming was also supported in our analysis of snake strikes (Whitford et al, ), as we found that any signaling behaviors greatly reduced the probability of a strike, as would be predicted for an ambush predator that relies on surprise to capture prey (Zuberbühler, Noe, & Seyfarth, ). It is also possible that foot drumming may act to warn conspecifics or nearby kin to the presence of a snake, thereby further reducing the ability of snakes to capture kangaroo rats in the vicinity; that said, the high degree of territoriality in desert kangaroo rats and large spatial separation between burrows seems to indicate that the display is directed toward the snakes and not conspecifics (Randall & Matocq, ).…”

“…The average amount of time a snake stayed within an ambush coil was 442 ± 197 min. From our recordings of snakes in ambush, we observed a total of 32 strikes from 15 snakes directed toward kangaroo rats; however, snakes never struck toward kangaroo rats that had performed any predator‐deterrent signals; all snake strikes occurred prior to any kangaroo rat signaling (strike behavior analyzed in Whitford et al, ). As snakes typically recoiled into their original ambush site after a strike and kangaroo rats would return and display toward the snakes, ambush coils involving strike attempts were retained in our analysis.…”

“…For example, Barbour and Clark () found that California ground squirrels only incorporated some type of physical harassment in 5% of interactions with free‐ranging rattlesnakes, while desert kangaroo rats sand kicked in 32/36 (89%) interactions. This propensity for desert kangaroo rats to kick sand may be driven both by the abundance of sand in the desert kangaroo rats’ preferred habitat and the powerful hindlimbs kangaroo rats use to both avoid snake strikes with propulsive jumps (Whitford et al, ) and kick snakes away in mid‐air to prevent envenomation (Whitford et al, ). Kangaroo rats can kick sand with their hindlimbs from 20–30 cm away, outside of the effective strike range of sidewinders (Clark et al, ).…”

“…We defined the start of an interaction as when the kangaroo rat exhibited any predator‐deterrent behaviors or when the snake struck at or reoriented toward a nearby kangaroo rat, indicating the snake was aware of the kangaroo rat's presence. The predator‐deterrent behaviors included sand kicks (using the hindlegs to kicks sand at the snake), jump backs (a close approach to the snake followed by rapid vertical leap away from the snake), foot drums (drumming of one hind foot), and foot rolls (rapid drumming of both hind feet)—video examples of the predator‐deterrent behaviors can be found in Whitford et al (). Kangaroo rats would often interact with a snake and then leave without returning for some time—for this reason, we defined an interaction as ending when 5 min had passed without any observable predator/prey behaviors or, if a snake abandoned during an interaction, the time of the abandonment behavior.…”

“…Individual elements within a display can encode information in numerous ways, including redundancy (same signal performed multiple times), degeneracy (multiple signals encoding identical information), or pluripotency (one signal encoding different information depending on context); signal elements can also interact to alter the intensity of the receiver's response or to provide emergent information (Hebets et al, ; Partan & Marler, ; Rowe & Guilford, ). Additionally, predators can respond to prey signaling in a variety of ways, including reduced overall probability of initiating an attack (Whitford, Freymiller, & Clark, ), targeting individuals of low physical quality (FitzGibbon & Fanshawe, ), or by abandoning pursuit and moving to a new hunting location (Barbour & Clark, ).…”