| dc.description.abstract | Small man-made ponds are the numerically dominant water body in the Great Plains, and they have been hypothesized to be sources of organic carbon (i.e. energy) to surrounding terrestrial food chains. Aquatic insects that live as immature forms in ponds emerge from the ponds as adults and transfer organic carbon from ponds to terrestrial ecosystems (i.e. carbon flux). Terrestrial predators such as birds and bats consume these insects. Pond permanence and the presence of fish are the primary factors controlling insect community structure and carbon flux. Permanent ponds contain fish, whose predation suppresses large aquatic insects and thereby reduces emergence and carbon flux. Temporary ponds that dry and refill periodically do not contain fish and have larger insect species and higher levels of emergence and carbon flux. The objective of my study was to assess how the flux of carbon from a permanent pond compares to a temporary pond after refilling and to evaluate the taxa-specific carbon flux in permanent and temporary ponds. I examined insect emergence in five permanent ponds with fish and in five temporary ponds that had dried and been refilled at the Eagle Mountain Fish Hatchery in Fort Worth, TX. I monitored the emergence of insects using floating insect emergence traps over a 10-week period. I captured over 48,000 insects, which were preserved in alcohol, counted and measured for body size. Insects were dried and weighed to determine biomass and carbon flux. Carbon flux from temporary ponds started within a week of pond refilling in the form of small midges, and increased throughout the 10-week period as increasingly larger taxa such as mayflies, damselflies, and dragonflies began to emerge. I found that it took two weeks after refilling for temporary ponds to have higher carbon flux than permanent ponds. | |
