Meeting Abstract
Palaemon macrodactylus, an invasive species of grass shrimp, were collected off the coast of of New Jersey waters to determine effects of light conditions on predation of two different species of grass shrimp, Palaemon macrodactylus and Palaemon pugio. Size also played a factor in my experiment. In this experiment, the Fundulus heteroclitus was the predator of the grass shrimps. This experiment was tested to determine if the invasive species of grass shrimp were better at defending themselves against predators than the native species in the absence and presence of light. This study was important because it will show us if the invasive species can compete better than native species, and if they can then eventually they will overtake the population and kick out the native species of shrimp. This can lead to a decrease of the native population or even possible extinction. Kaplan-Meier survival curves and Cox proportional hazards regression was used to study the effects of species and lighting condition on risk of death due to predation. A significant (p = 0.015) crossover interaction between species and lighting on risk of predation was observed, where the hazard ratio comparing risk in full darkness to full light for Palaemonetes pugio was 4.5 times that value for Palaemon macrodactylus.
