Effects of Urbanization on Nekton Abundance and Food Web Structures in Southeastern Tidal Creeks
Jones, Sara Elizabeth
Tidal creek systems serve as sentinel habitats, areas where the effects of human impacts may be seen before adverse affects are detectable in the larger ecosystem. Patterns of abundances of nekton in southeastern tidal creeks draining four land use classes were determined. Lower abundances of Palaemonetes shrimp species were found in headwater tidal creeks with higher levels of human impact. The pinfish Lagodon rhomboides was found in higher abundances in larger creeks having increased levels of human impact in the watersheds. A simplified food web of small nekton in six South Carolina tidal creeks was studied to illuminate one possible pathway for land use to affect the abundances of nekton. Food web analysis showed that the diets of shrimp in the more highly impacted creeks shifted from being dominated by particulate organic matter in the reference creeks to more varied diets in urban creeks, thus suggesting that alterations in the food web are one possible cause for the alteration in abundances of nekton with increasing levels of human impact.
Ecology; Organismal biology; Nekton; Food webs; Estuarine ecology