Meeting Abstract
When faced with predation risk, many species evade the threat through escape behavior, which may include moving to new habitats. Avoiding predation, though beneficial, comes with costs, so prey must be able to recognize and distinguish between threat levels to respond appropriately. Mangrove rivulus fish (Kryptolebias marmoratus) have the ability to emerse—exit the water, into air—and locomote on land to find different environments. We hypothesized that rivulus would emerse to avoid predation by mangrove water snakes (Nerodia clarkia compressicauda). We further hypothesized that the geographical origin of the fish would influence the latency to emerse after exposure to predator cues. To test these hypotheses, fish from three different regions of Florida were collected and exposed to chemical cues from water snakes that had been fed rivulus or fasted; deionized water was the control. Latency to emerse following cue presentation was compared across populations and geographical regions to determine whether fish exposed to more informative cues of predation threat (snake fed rivulus) would show shorter latencies to emerse than fish exposed to cues indicating only predator presence (fasted snake) or control. Preliminary analyses indicate strong population-level differences in the tendency and latency to emerse and moderate regional differences in emersion behavior. Contrary to our prediction, we found little evidence that predator exposure regimes influenced emersion behavior. Future analysis will use Noldus Ethovision XT software to more precisely analyze behavioral data, including distance and speed traveled, latency and duration of emersions, and number of emersions that occurred during the trial period. These data suggest that selection pressures other than predation might drive local adaptation of emersion behavior in rivulus.
