Date of Award
Master of Science (MS)
College of Science and Mathematics
Marine Biology and Coastal Sciences
Thesis Sponsor/Dissertation Chair/Project Chair
Seagrasses--New Jersey--Barnegat Bay, Benthos--Habitat, Benthos--Food
During the summer, seagrass blades are frequently released into the water column as a method to reduce respiration demands of the plant and through physical disruption of the bed (e.g., crab foraging, boat propellers). This wrack has the potential to serve as both food and habitat for organisms dislodged or actively moving within the system. The purpose of this research was to determine how benthic organisms may use floating wrack as a food resource and shelter. Three experimental floating wrack bag treatments were assembled containing using artificial Zoster a marina (i.e., poly-ribbon), Z. marina blades, and a wrack bag control in order to examine if organisms prefer to use wrack for food, shelter, or both. Wrack bags were placed in Bamegat Bay, NJ during the summer of 2015 with collection and replacement of experimental bags occurring bi-weekly. Benthic core samples were taken as well to determine if the benthic organisms matched that of the fauna found in floating wrack. The major organisms identified in this study include Peracarid crustacean dominated by Corophiidae, Aoridae, Caprellidae, Idotea balthica, Erichsonella spp., Gammaridae, and Melitidae. In general, the results demonstrate a clear preference by amphipods and isopods for Z. marina wrack over the artificial Z. marina. The same taxa found in treatment bags were also found in core samples, albeit their relative abundances differed among the different taxa. The stable isotope analysis showed carbon signatures for faunal taxa similar to algae and/or Ruppia maritima. However, it appears that isopods showed combined N and C signatures similar to R. maritima, while the amphipods showed signatures closer to algal food resources. When assessing the overall results of my research, results showed that there was a lack of solitary response to the artificial Z marina. Therefore, I conclude that benthic organisms use wrack as refuge and potential transport mechanism, but also may obtain trophic resources from them. However, the trophic resources are not coming from Z marina, but most likely from associated epiphytic algae. As such, there may be a potential benthic-pelagic link occurring due to a clear distribution of organisms from the benthos into the pelagic zone via floating wrack.
McGinnis, Joseph R., "Experimental Assessment of Floating Seagrass Wrack as Potential Habitat for Benthic Organisms" (2016). Theses, Dissertations and Culminating Projects. 515.