I am broadly interested in reptile and amphibian conservation and behavior. More specifically, I want to study the distribution of amphibians in urban and suburban areas and other highly modified landscapes.
Amphibians can often be found breeding in artificial water sources in these highly altered landscapes, such as golf course ponds, storm water retention ponds, road side ditches, and also in artificial wetlands (personal observation; Hamer et al, 2012; McCarthy and Lathrop, 2011; Scheffers and Paszkowski, 2012; Skelly et al, 2010; Boone et al, 2008). Frequently, the buffer zones of undeveloped land around these water features are quite small. Research has shown that several amphibian species need more buffer space than is often provided around water sources, especially those found in cities and towns (Hawkes and Gregory, 2012; Harper et al, 2008). Additionally, population declines have been found to be caused by lack of connectivity between the habitat fragments that remain in urban landscapes, as fragmentation makes some suitable sites essentially unreachable to amphibians (Pillsbury and Miller, 2008). I am curious about microhabitat use by amphibians in these less than ideal habitats. Do amphibians utilize features of the urban landscape beyond the buffer zone? Are there some urban features that actually provide suitable surrogate sources of foraging territory and refugia? Understanding how amphibians can make use of urban spaces will allow me to recommend what sort of urban features are appropriate around an urban water source, and perhaps help me discover ways to improve a habitat that was not originally intended for amphibian use so that narrow buffer zones can effectively be expanded without completely redesigning an already developed area. For example, some golf courses have buried sprinkler boxes which frogs and toads can use during hot summer months as refugia (personal observation), so increasing the number of artificial, below ground spaces would theoretically create more refugia for those animals. I am also curious to see whether the installation of suitable microhabitat features in the matrix between habitat fragments could increase connectivity between those sites. In Davis, California, in the mid nineties a several mile long tunnel was installed to help toads migrate through the urban landscape. I cannot find any peer reviewed documents discussing this project, though the anecdotal consensus seems to be that it never worked and toads ended up overheating and dying in the tunnel during the summer. Nevertheless, the idea of a short underground migration pathway for amphibians to get across roads might prove to be a good idea. Perhaps a city's own culvert system could be adapted to do double duty as an amphibian road crossing tool. Development of open spaces for human use is not likely to slow in the near future. Consequently, we need to work to make highly modified environments suitable for the needs of both humans and the wildlife around them. |  References
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