Synergistic effects of musking and autohemorrhaging on the duration of death feigning in dice snakes (Natrix tessellata)

Predation exerts a significant selection pressure on prey, shaping a
multitude of traits that serve as antipredator defences. In turn, natural
selection could favour combinations of antipredator defences with
synergistic effects that enhance prey survival. An especially interesting
antipredator defence is death feigning (DF), present in a wide variety of
taxa and usually characterized by the prey lying motionless often along
with defecation, musking, and auto-haemorrhaging. All these aspects of DF
should work in conjunction with one another, intensifying the overall
effect of the display and in turn facilitating quicker escape. To confirm
this hypothesis, we tested 263 dice snakes (Natrix tessellata) directly in
the field. We noted the occurrence of smearing faeces and musk and
autohaemorrhaging and we measured the duration of DF, expecting to see a
negative association between the occurrence of these behaviours and the
duration of DF. Our results affirm our hypothesis: dice snakes that
smeared themselves in musk and faeces before DF and had auto-haemorrhaging
during DF spent significantly less time in DF. Our results highlight the
functional integration of antipredator behaviors across different phases
of predator-prey interactions, emphasizing the need for future research to
prioritize studying the sequential display of behaviors.