Date of Award

Spring 5-8-2020

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Animal Sciences

Advisor

Robert Bayer

Second Committee Member

Ian Bricknell

Third Committee Member

Timothy Bowden

Abstract

Habitat loss and degradation caused by the installation of infrastructure related to coastal population increase removes vital habitat necessary in the lifecycles of benthic and epibenthic species. Of the species affected, the American lobster is the most commercially valuable specie in the Gulf of Maine, and it has been proposed that lack of suitable habitat could potentially limit lobster distribution and population. Granite block mooring systems (GNT) are essential in anchoring boats and equipment related to marine recreation and industry, the footprint of the GNT removes benthic habitat and does little to enhance epibenthic habitat. In an effort to support the sustainability of the lobster fishery, Habitat Mooring Systems™ designed a multifunctional artificial reef (HMS4000), which serves as both a marine mooring system and potential lobster habitat. A granite mooring system was compared to an HMS4000 at Seal Harbor, Mount Desert Island, ME and Sand Cove, South Bristol, ME, to understand the effectiveness of the HMS4000 to increase species richness, lobster abundance, lobster biomass, crab abundance, and fish abundance in, on or around the mooring. Data collection consisted of lobster counts, lobster carapace length, lobster sex, crab identification and count, fish identification and count, and all other invertebrates were identified and counted. Crabs were divided into two groups, 1) Jonah/rock crab, and 2) “Other crabs” where all other crabs were identified, counted and cataloged. Four dive surveys were performed at each location between July 26, 2012 and February 14, 2013. The HMS4000 had a significantly higher species richness compared to the control groups at Seal Harbor, and higher lobster inhabitance compared to the GNT overall. The HMS4000 at both locations had similar lobster occupancy and calculated lobster biomass. Lobster carapace length on the HMS4000 was larger than other treatments, and the male to female lobster ratio was close to that of the control site, however there were no significant differences between treatments. Although Jonah/rock crab were found on the HMS4000, the GNT had significantly more, but, with less lobster abundance, the GNT had fewer resident predators and provided adequate shelter for this species group. No significant differences in fish prevalence were found, but fish had a greater tendency to use the artificial habitat over the GNT and control. Commercially valuable fish species, such as Atlantic cod and American eel, were exclusively surveyed on the HMS4000. In conclusion the HMS4000 could alleviate habitat degradation through the mitigation of benthic habitat loss generated from a foot print of traditional granite mooring, by increasing overall species richness and providing suitable habitat that would support commercially and recreationally valuable species such as, the American lobster, Atlantic cod, Jonah crab, and American eel.

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