Discerning the Trophic Niche of the Non-Indigenous Polychaete, Hermundura americana, in the Chesapeake Bay Using Stable Isotopes
College
College of Sciences
Department
Department of Biological Sciences
Graduate Level
Master’s
Graduate Program/Concentration
Biology
Presentation Type
Oral Presentation
Abstract
Benthic ecology- the study of ecological interactions within the ocean floor- requires understanding nutrient cycling, the transfer of energy in the food web, and the processing of toxic compounds. Benthic food webs include polychaete worms, amphipods, crustaceans, shellfish, brittle stars, and other organisms. These food webs are vulnerable to non-indigenous taxa known to displace native species, alter energy production, and change nutrient cycles. For example, a non-indigenous polychaete of the pilargid family, Hermundura americana, was first collected in the Southern Branch of the Elizabeth River in 2009. Since that time, this species has spread throughout some brackish regions of the Chesapeake Bay, often in high densities. This polychaete is in the Pilargid family, a family whose life history, behavior, reproduction, and feeding strategies are seldom studied due to the fact that they typically occur in extremely low abundance and cannot be found reliably. Potential trophic interactions with native benthic species remain unknown since a pilargid polychaete has never been found in as high abundance as H. americana. Using stable isotope analyses of carbon and nitrogen this study will attempt to define the trophic niche of H. americana to identify possible alterations in the ecological functioning of benthic food webs of brackish areas of the Chesapeake Bay. This study will serve as the basis for understanding of this invasive species and to inspire further monitoring of the behavior and life cycle of H. americana in this region.
Keywords
Polychaete, Benthic Ecology, Invasive species, Stable isotope analyses, trophic niche
Discerning the Trophic Niche of the Non-Indigenous Polychaete, Hermundura americana, in the Chesapeake Bay Using Stable Isotopes
Benthic ecology- the study of ecological interactions within the ocean floor- requires understanding nutrient cycling, the transfer of energy in the food web, and the processing of toxic compounds. Benthic food webs include polychaete worms, amphipods, crustaceans, shellfish, brittle stars, and other organisms. These food webs are vulnerable to non-indigenous taxa known to displace native species, alter energy production, and change nutrient cycles. For example, a non-indigenous polychaete of the pilargid family, Hermundura americana, was first collected in the Southern Branch of the Elizabeth River in 2009. Since that time, this species has spread throughout some brackish regions of the Chesapeake Bay, often in high densities. This polychaete is in the Pilargid family, a family whose life history, behavior, reproduction, and feeding strategies are seldom studied due to the fact that they typically occur in extremely low abundance and cannot be found reliably. Potential trophic interactions with native benthic species remain unknown since a pilargid polychaete has never been found in as high abundance as H. americana. Using stable isotope analyses of carbon and nitrogen this study will attempt to define the trophic niche of H. americana to identify possible alterations in the ecological functioning of benthic food webs of brackish areas of the Chesapeake Bay. This study will serve as the basis for understanding of this invasive species and to inspire further monitoring of the behavior and life cycle of H. americana in this region.