Predation rattlesnakes

In a number of species, the active predator odors originate on the dorsal skin. Neonate pygmy rattlesnakes, Sistrurus miliarius, and timber rattlesnakes, C. horridus, respond to dorsal skin chemicals of the ophiophagous king snakes and indigo snakes, Drymarchon corais, but not to those from ventral skin or skin... 

In black-tailed deer, Odocoikus hemionus columbianus, fecal odors of sympatric predators (coyote, C. latrans, and mountain lion, Fdis concolor) in vials next to food pellets inhibited feeding, while those of allopatric predators (lion, Fdis leo, snow leopard, Uncia uncia) do not, or very little (Miiller-Schwarze, 1972 Fig. 12.3). Note that mammals discriminate between the odors of sym- and allopatric predators, while fish and rattlesnakes do not (pp. 359 and 364). Free-ranging adult female wapiti, Cervus elaphus canadensis, respond to the odors of dog urine, and cougar and wolf feces (presented as water slurry) with increased heart rates. It was concluded that the main effect of predator odors may be for assessing the risk of predation (Chabot etal, 1996). 

Rundus AS, Owings DH, Joshi SS, Chinn E, Giannini N (2007) Ground squirrels use an infrared signal to deter rattlesnake predation. Proc Nat Acad Sci USA 104 14372-14376... 

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