Evaluating Land Use Effects On The Stinging Sea Nettle : Chrysaora Quinquecirrha: Are Shoreline Hardening Structures Creating New Habitat For A Nuisance Species?

Abstract

There is considerable debate as to whether global jellyfish populations are experiencing an overall population growth due to human activities or have been pulsing in a long-term natural rhythm. Empirical data to support either hypothesis are lacking and one hypothesis links coastal construction to a rise in jellyfish. This hypothesis states that shoreline stabilization and coastal construction is providing more suitable substrates for polyps to settle upon and asexually reproduce the nuisance medusa stage. The goal of our study was to empirically test jellyfish settlement on various substrates. Using both field and laboratory techniques, polyps of the Atlantic Sea Nettle (Chrysaora quinquecirrha) were tested for recruitment and excystment on oyster shell, PVC vinyl, granite rock and stainless steel. Due to higher than average rainfall and lower than average salinities at our study sites, our field experiment did not yield conclusive results. In laboratory conditions, polyps exhibited significantly higher settlement (p < 0.0001) on steel than any other substrate. We then used the data collected in the laboratory to determine crude future estimations of the abundance of sea nettle polyps in the Neuse River Estuary. The results from this project imply that polyps experience greatest survival on an artificial substrate, which could support the theory that with increased construction will come an increase in jellyfish blooms.