Effects of density on spacing patterns and habitat associations in the Neotropical Glassfrog Espadarana Prosoblepon
Results/Conclusions Pre-decline density across all transects was 0.034 ± 0.02 males/m and that declined to 0.019 ± 0.02 males/m post-decline. Nearest neighbor distance did not change with density, and averaged 0.692 ± 0.74 m across all transects and years. Post-decline the number of hotspots decreased from 30 to 20, but 18 of 20 (90%) post-decline hotspots were located in the same locations as pre-decline clusters, although comprised of all new individuals. To document whether male frogs were associated with habitat features differently in high and low density years, we quantified habitat characteristics on 48 10-m stream reaches before and after the invasion of Bd. Principle components analysis showed that males were strongly associated with the amount of leafy vegetation along the stream in both years. Post-decline stream substrate and hydrology increased our ability to predict male frog abundance. Because dispersion patterns are not affected by changes in population density, we conclude that male E. prosoblepon are selecting large scale habitat features that have not greatly changed in the 12 year study period. This is the first report of lek-like behavior or resource defense for the prolonged breeder E. prosoblepon. This study also reveals that adult frog spacing and locality stays consistent after Bd invaded.