Ecology

The gopher tortoise (Gopherus polyphemus) is endemic to the Southeast United States, where its populations are declining primarily due to habitat loss. Gopher tortoises prefer habitats with open sunny spots for nesting and basking. Fire is a normal element in gopher tortoise habitat, and when natural fires are suppressed, habitats may become too overgrown. To maintain the open spaces, some land managers use reduction mowing of vegetation. I studied gopher tortoises in the Abacoa Greenway reserve, established to protect the tortoises in a residential area of Jupiter, Florida, and I examined how reduction mowing influences tortoise activity. I evaluated the distribution of burrows throughout the study site by flagging the burrows both before and after extensive reduction mowing took place in the greenway. Statistical comparison between new burrows found within the interior as compared to the periphery both before and after the mowing reveal a significant relationship between both variables. These results suggest that the tortoises utilize newly mowed areas as preferred substrate for new burrows.

Habitat fragmentation causes the isolation of groups of individuals within species by producing a new landscape that is uninhabitable for many species, including birds. I surveyed the John D. MacArthur campus of FAU in the Fall of 2005 and Spring of 2006 to assess the use of the campus by birds. Throughout the campus trees are lined in rows along the sidewalks and around buildings, in contrast to the pine flatwoods environment that existed prior to development. The birds observed were found performing various activities on the campus, including foraging, perching, and building nests. Individuals were concentrated around or near buildings with the most diverse vegetation. Through assessing these campus uses I suggest that there are ways we can help increase bird diversity in promoting their use of urban environments. Such solutions can help decrease the number of individuals and species lost to the destructive force of habitat fragmentation.

The construction of Abacoa included an attempt to conserve the wildlife in a Greenway, a set of habitats separated from the residential and commercial areas. All of the wetlandswith in Abacoa represent artificially constructed ponds, canals, and streams first created from 1998-2004. The present study focuses on the anuran (i.e., frog and toad) populations and looks at the number of different species that have naturally colonized six differnet sites around Abacoa. Each of these sites varies in qualities that may affect the probability of breeding in that section. The quality of water is known to be less ideal as the water flows away from the headwaters and mixes with water from other sources. This study aims to determine which anuran species are found at each of these sites after nearly a decade of colonization, and how both anuran diversity and abundance correlates with water and habitat quality.

Coral reefs harbor ~1-9 million species, including 30% of all marine fish species. Reef health worldwide is declining due to many factors: e.g. pollution, sedimentation, dynamite fishing, and global warming. Working with the Planetary Coral Reef Foundation and the crew aboard the R/V Heraclitus, I examined coral health and fish diversity in the Solomon Islands, Melanesia. In 2006, I surveyed coral and fish on Sagharughombe reef, Solomon Islands using SCUBA and compared the results with surveys done in 2000 and 2002. Coral surveys indicated a significant decline in health over the six-year period. Fish surveys found no clear trend in species abundances and species richness, but a significant decline in species diversity over the years. The decline in coral health we observed may have contributed to diminished fish diversity. To protect marine biodiversity, coral reefs must be better protected and declines in coral health must be halted.

Florida's pine flatwoods are pyrogenic ecosystems that require frequent fires to regenerate the herbaceous layer and suppress crowding vegetation. Human development has hindered these natural fires and consequently affected the herpetofauna (amphibian and reptile) species. Anthropogenic encroachment, in addition to fire suppression, has also provided ideal habitats for invasive species within native environments. Exotic species are often found in developed areas around buildings and roads, and it is likely this pattern continues into the park. This eight-month coverboard survey focuses on the effects various fires may have on herpetofauna in the area and explores the level of intrusion exotic species exhibit within the communities. Minimal differences among herpetofauna composition between transects were found. However, a convincing percentage of exotic species were found only within the first ten meters of the transects while all native species were at least 25 meters into a transect.

Greenways are corridors of relatively intact natural vegetation through otherwise disturbed habitat that typically connect larger protected natural areas. The establishment of greenway systems throughout the United States is a testament to the increasing recognition of the necessity to incorporate wild areas within urban and other disturbed landscapes for the sake of biological sustainability and the emotional welfare of human residents. In my thesis, I examine a local greenway in Jupiter, Florida, the Abacoa Greenway, which is both product and component of the greenway movement, a recent and revolutionary phenomenon in urban planning. I evaluate the greenway's ecology, the specific functions it serves, and its significance within the broader realm of environmental ethics. The primary protected habitats are a mixture of scrubby pine flatwoods and shallow wetland basins. The flatwoods provide important habitats for numerous native species, including the gopher tortoise (Gopherus polyphemus) and the many commensal species that live in the tortoises' burrows. The shallow wetland basins also serve a number of purposes, including a surface water management system. As a whole, the greenway is an important resource for human recreation and environmental education, including scholarly research by students and faculty at Florida Atlantic University. It serves as important link between people and nature in an urban setting where they might otherwise be completely estranged.