Small temporary ponds are important and diverse ecosystems. Their ephemeral nature precludes the presence of fish predators, and supports species adapted to pond drying. For instance, many amphibians and macroinvertebrates rely exclusively upon temporary ponds for breeding and larval development. Unfortunately, small ponds have historically been destroyed or severely altered by nearby development. I have initiated several projects to assess how humans influence these pond ecosystems.
Created Mitigation Ponds
Temporary ponds are often created in order to mitigate ponds that were destroyed in development projects. I worked with Mary Beth Kolozsvary to compare the physical, chemical, and biotic characteristics of natural, forested ponds to a set of created ponds. We found that created ponds did not functionally match our set of reference ponds. Specifically, most created ponds held water for too short or too long of time to mimic the hydrology of natural temporary ponds. Created ponds were also smaller, sunnier, and had more Phragmites and Typha, which are two aggressive plant species that can take over wetlands. In terms of the animal community, macroinvertebrate assemblages starkly differed and created ponds had fewer key temporary pond amphibians, such as the spotted salamander and wood frog. Overall, we found that the ability for created ponds to match the ecological functions of natural ponds was suspect. Check out our publication in Wetlands!
As a collaborative effort in the Skelly Lab, I led a project to study how suburban land use affected pond food webs. We found that septic tanks leak wastewater nitrogen into ponds, which is then picked up in the food web. A dominant pond consumer, the wood frog, also switched its diet from mostly leaf litter-pathways in the least developed sites to predominantly algal-pathways in the most suburban sites. This work is in press at Canadian Journal of Fisheries and Aquatic Sciences.