Mother Cottonmouths (Agkistrodon piscivorus) Alter Their Antipredator Behavior in the Presence of Neonates

Neonate-directed care is rare in non-avian reptiles, but female pitvipers attend their young for a period of time after birth. One of the primary functions of parental care is the protection of offspring from predators, and parents of diverse taxa are able to modulate their antipredator behavior in the presence of offspring. To test the hypothesis that the antipredator behavior of post-parturient pitvipers is altered during neonate attendance, we conducted behavioral trials on female cottonmouths (Agkistrodon piscivorus) in which we measured female response to a simulated predator encounter. Cottonmouths were divided into three treatment groups: (1) post-parturient, attending neonates; (2) post-parturient, not attending neonates; and (3) non-reproductive. All females were subjected to a second trial approximately 3 wk later, when females in Group 1 were no longer attending neonates. When mothers were attending offspring, they were more hesitant to engage the predator and exhibited more warning than aggressive behaviors once they did, relative to nonattending and non-reproductive females. When these same mothers were no longer attending offspring, they significantly increased their antipredator behavior by engaging the predator quickly and displaying more aggressive than warning behaviors. This change in behavior was not observed in post-parturient females who did not have neonates present during either trial, nor was it observed in non-reproductive females, indicating that the presence of neonates directly affected the antipredator behavior of attending females. We discuss hypotheses concerning the possible adaptive value of reduced antipredator behavior in female pitvipers attending neonates.