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Meeting Abstract

SICB+    Rare climate events and competition constrain establishment success in Anolis lizards Nicholson, DJ*; Knell, RJ; McCrea, R; McMillan, WO; Neel, LK; Chung, AK; Curlis, JD; Garner, TWJ; Cox, CL; Logan, ML; Smithsonian Tropical Research Institute and Queen Mary University London; Queen Mary University London; University of Kent; Smithsonian Tropical Research Institute; Arizona State University ; Princeton University; University of Michigan; Zoological Society of London; Florida International University; University of Nevada, Reno danielnicholson49@gmail.com

The establishment of populations in novel environments is a crucial biological process with important implications for conservation biology and the study of adaptive radiations. A deep understanding of how ecological and environmental circumstances facilitate or constrain population establishment is vital, but there are currently some important gaps in our understanding of this process. Crucial questions include: 1) To what extent does community context (e.g., the presence of competitors) change the probability of establishment? 2) Does the timing of initial arrival relative to stochastic events, such as climatic perturbations, impact the probability of successful establishment? 3) In what ecological contexts do males outperform females (and vice versa) during the process of establishment? We introduced slender anole lizards (Anolis apletophallus) to eight islands in the Panama Canal to investigate the factors that facilitate or limit successful establishment. These islands were warmer than the mainland (ancestral) environment and varied in the presence or absence of a native competitor species. We established half of these populations in 2017 and half in 2018, with a severe drought happening in early 2019. We tracked each population for multiple generations and found that the probability of extinction depended on both the intensity of interspecific competition and the timing of establishment relative to the drought. Further, establishment success differed based on sex, with males suffering, and females benefitting, from the presence of a native competitor. Our results reveal that community context and the timing of initial arrival relative to rare climate events may combine to determine establishment success and that these factors can generate opposite effects on males and females.