Garter snake pheromone trails

Ford, N.B. (1981) Seasonality of pheromone trailing behavior in two species of garter snake, Thamnophis (Colubridae). Southwest. Nat. 26, 385-388. 

LeMaster, M.P. and Mason, R.T. (2001) Evidence for a female sex pheromone mediating male trailing behavior in the red-sided garter snake, Thamnophis sirtalis parietalis. Chemoecology 11, 149-152. 

Male garter snakes do not pursue already mated females. These females carry a gelatinous mating plug in their cloaca for about 2 days. Copulatory fluids around her cloaca contain a copulatory pheromone that inhihits males advances. Males detect this copulatory pheromone on a female s trail hy tongue flicking from a distance (O Donnell etat. 2004). 

Red-sided garter snakes from different regions of Manitoba, Canada show signs of isolation by chemical cues. In choice tests, males from a hiber-naculum (overwintering den) in central Manitoba preferred females from their own population to females from western Manitoba. Males from western Manitoba showed no preference. When confronted with experimental trails, males made the same choices. This demonstrated that a chemical factor is involved. Furthermore, the sexual attractiveness pheromone of females, a series of ty-9-cis-unsaturated methyl ketones, varies between the populations. Specifically, the... 

Species specificity of sex pheromone trails of sympatric and allopatric garter snakes Thamnophis). Copeia 1,10-13. 

Ford, N. B. and Low, J. R. (1984). Sex pheromone source location by garter snakes a mechanism for detection of direction in nonvolatile trails. Journal of Chemical Ecology 10, 1193-1199. 

Ford, N. B., 1978, Evidence for species specificity of pheromone trails in two sympatric garter snakes, Thamnophis, Herpetol. Rev., 9 10. 

Table 5. Ability of male plains garter snakes, Thamnophis radix to determine direction of a female pheromone trail under three different physical conditions. For experiments I and II a one-tailed binomial test of the hypothesis that the males would follow the trail in the direction of the female was conducted. For experiment III the hypothesis tested was that the males would go the direction the pegs "indicated . From Ford and Low (1984). 

An optimal group in which to examine trail pheromone evolution is the garter snakes of the Thamnophis radix complex. In the United States, this complex consists of six recently evolved but distinct species radix,... 

Ford, N. B., 1979, Aspects of Pheromone Trailing in Garter Snakes (Thamnophis), Ph.D. Dissertation, Miami Univ. Ohio. 

Ford, N. B., and O Bleness, M., in press. Species and sexual specificity of the pheromone trails of the checkered garter snake, Thamnophis marcianus, J. Herp. 

Ford, N. B., and Schofield, C. W., 1984, Species specificity of sex pheromone trails in the plains garter snake, Thamnophis radix, Herpetologica 40 51. 

Costanzo, J. 1989. Conspecific scent trailing by garter snakes (Thamnophis sirtalis) during autumn further evidence for use of pheromones in den location. J. Chem. Ecol. 15 2531-2538. 

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