Garter snakes do not respond to TTX via chemoreception

Abstract

Snakes detect and recognize prey through chemoreception using their tongue, but can they also detect toxins secreted by prey? Taste-rejection has been described in predators as a means of sampling prey for toxicity prior to ingestion but at the cost of minor intoxication and energy expenditure. Toxin detection prior to attack of prey might reduce these costs. Thamnophissirtalis (common garter snake) is among the predators that have been shown to employ taste-rejection of toxic prey but, as with all snakes, they primarily use vomeronasal chemoreception to evaluate potential prey. We investigated whether T. sirtalis use chemoreception as means of perceiving tetrodotoxin (TTX) found in their newt prey. We used the common tongue-flick behavioral assay to evaluate response to TTX and found that naive T. sirtalis did not respond differently to the toxin than a control. We conclude that T. sirtalis cannot detect TTX by chemoreception, or do not alter their behavior if they do.