Meeting Abstract

64.2  Monday, Jan. 6 08:15  Life history plasticity associated with the climate change-mediated range expansion of a coastal decapod RILEY, M.E.*; GRIFFEN, B.D.; University of South Carolina; University of South Carolina rileyme3@email.sc.edu

The geographic ranges of most plants and animals are limited by climatic factors, and changes in global climate trends have caused species from a wide array of taxa to shift or expand their distributions into higher elevations and latitudes. Due to differences in the type and timing of species’ responses to climate changes, the range expansions of many animals outpace that of their habitat. One such example is the mangrove tree crab Aratus pisonii, a mangrove herbivore whose northward movement recently outpaced that of its native habitat, leading to the establishment of populations in salt marsh vegetation. Organisms such as A. pisonii that expand their range into foreign environments often alter their life history traits in an attempt to maximize their reproductive success under the challenges presented by these new habitats. In order to explore potential alterations in the life history characteristics of A. pisonii as it expands its range, we compared populations from mangroves within the species’ historical range and from salt marshes near its current northernmost distribution. We examined body size distributions, size at maturity, and reproductive effort of populations from both areas. Additionally, we investigated differences in the maternal reproductive investment of individuals from both populations by comparing egg size, brood size, and starvation resistance of recently hatched zoeae. This study details the reproductive strategy of a major mangrove consumer as it colonizes novel salt marsh habitats, and provides insight into the potential mechanisms enabling this species and countless others to successfully expand their range into novel environments.