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Casselberry, Grace

MSc, IMS

 

Project Title:

The spatial ecology of the shark community in Buck Island Reef National Monument, St. Croix, USVI

Contact:

gcasselberry@umass.edu

Support:

U.S. National Park Service, New England Aquarium’s Marine Conservation Action Fund, Atlantic White Shark Conservancy

Faculty Advisors:  Andy Danylchuk and Greg Skomal

Project Abstract:

Marine protected areas (MPAs) are becoming an increasingly popular marine conservation tool, particularly for elasmobranchs.  Although Buck Island Reef National Monument (BIRNM), St. Croix, United States Virgin Islands, is one of the oldest MPAs in the US, information on the movement ecology of sharks in its waters is lacking.  From June, 2013 – November, 2016, nurse (Ginglymostoma cirratum; n = 10), lemon (Negaprion brevirostris; n = 5), tiger (Galeocerdo cuvier; n = 5), and Caribbean reef (Carcharhinus perezi; n = 12) sharks were acoustically tagged and monitored using a passive acoustic telemetry array.  Network analyses were used to evaluate the extent to which tagged sharks utilized the MPA, while bipartite graphs coupled with community detection algorithms were used to quantify spatiotemporal dynamics of sharks in BIRNM.  Spatial networks for individual sharks displayed behavioral differences among species and individuals.  Although preliminary, the results of this study indicate that BIRNM provides varying degrees of protection for all species tagged.  Individual spatial networks revealed that most individuals used the array widely over prolonged periods of time, with 23 tagged sharks remaining within the MPA boundaries for six months or longer.  Two lemon sharks and one Caribbean reef shark were present for the entire duration of the study.  Bipartite graphs show similarities in array use within species, particularly for tiger and lemon sharks, while nurse and Caribbean reef sharks displayed greater individual differences.

Recent publications:

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Graytail Skate (Bathyraja griseocauda). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-04.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Daggernose Shark (Isogomphodon oxyrhynchus). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-05.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Striped Smoothhound (Mustelus fasciatus). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-06.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Narrownose Smoothhound (Mustelus schmitti). Report to the National Marine Fisheries Service, Office of Protected Resources.  SFD Contribution PCB-15-07.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Brazilian guitarfish (Rhinobatos horkelii). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-08.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the Argentine angel shark (Squatina argentina). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-09.

Casselberry, G.A. and J.K. Carlson.  2015. Endangered Species Act Status Review of the spiny angel shark (Squatina guggenheim). Report to the National Marine Fisheries Service, Office of Protected Resources. SFD Contribution PCB-15-10.

 

Page updated: March 22, 2017