Weather

The green iguana (Iguana iguana) is an herbivorous lizard native to South America and is invasive in south Florida. The severe weather in January 2010 negatively impacted many species and significantly reduced the green iguana population, specifically adult females and juveniles of both sexes. Fifteen adult iguanas from two locations in Palm Beach County were tagged and had blood drawn for blood chemistry and HPLC steroid hormone analysis. Individuals were tracked for home range/territory analysis and behavioral observations. Blood chemistry values of cold-stunned individuals showed abnormal values similar to those reported in cold-stunned sea turtles. Territoriality and breeding behaviors, including nesting and head-bob displays, decreased or ceased during the following months. Steroid hormone concentrations were detected by HPLC and were not consistent with results from RIA studies in the literature.

Demographic changes, through immigration/emigration (or death) can affect the social and community structure of a population. This study reports on the effects of demographic changes following 2 intense hurricanes on two sympatric delphinid species: Atlantic bottlenose dolphins, Tursiops truncatus, and Atlantic spotted dolphins Stenella frontalis. Thirty percent of the bottlenose population was lost after the hurricanes, with an influx of roughly the same number of immigrants. The stable community split into two cohesive units. Preferences in association in relation to reproductive status and sex remained. Immigrants assimilated well into the population, especially males. There is a conflict of interest between resident males and females in accepting immigrants and often females find more resistance than males. Long-term analysis of spotted dolphins revealed a community structure defined by long-term site fidelity, natal philopatry of both sexes and three social clusters.