Horizontal and vertical movements of Caribbean reef sharks ( Carcharhinus perezi ): conservation implications of limited migration in a marine sanctuary

Abstract

Despite the ecological and economic importance of the Caribbean reef shark (Carcharhinus perezi), little data exist regarding the movements and habitat use of this predator across its range. We deployed 11 pop-up satellite archival tags on Caribbean reef sharks captured in the northeast Exuma Sound, The Bahamas, to assess their horizontal and vertical movements throughout the water column. Sharks showed high site fidelity to The Bahamas suggesting Bahamian subpopulations remain protected within the Bahamian Shark Sanctuary. Depth data indicate that Caribbean reef sharks spent a significant proportion (72–91%) of their time above 50 m in narrow vertical depth bands, which varied considerably on an individual basis. This may be indicative of high site fidelity to specific bathymetric features. Animals exhibited three broadly categorized sporadic off-bank excursions (more than 50 m excursions) down to a depth of 436.1 m, which were more frequent during the night. These deeper excursions during night may be indicative of foraging in relation to prey on mesophotic reefs, as well as diel-vertically migrating prey from the deeper meso- and bathypelagic zones. These vertical movements suggest that Caribbean reef sharks can be significant vectors of ecosystem connectivity further warranting holistic multi-system management and conservation approaches.

Skating on thin ice: Identifying the need for species‐specific data and defined migration ecology of Rajidae spp.

“…Therefore, due to the generally demersal nature of skates, real‐time geolocation estimates are often not possible, and discerning horizontal movements via this approach is difficult (Farrugia et al., ). Even when geolocation estimates can be derived, the data provided are of coarse resolution, and error associated with latitude and longitude estimates can preclude definitive interactions with management boundaries (Shipley et al., ). Satellite transmitters are further hindered by battery life, which rarely exceeds 12–18 months, assuming no attachment failure throughout the deployment duration.…”

Exercise intensity while hooked is associated with physiological status of longline-captured sharks

“…It should be noted that while we suggest Caribbean reef sharks are more vulnerable to changes in physiological status owing to longline capture, both species had 100% at-vessel survival and are generally considered to be physiologically resilient to capture (Brooks et al , 2012, 2013; Gallagher et al , 2017; Jerome et al , 2018). In addition, other studies have documented very high post-release survival estimates following longline capture for Caribbean reef sharks (Brooks et al , 2011b; Shipley et al , 2017). We are unaware, however, of the potential for Caribbean reef sharks or nurse sharks to experience negative long-term sub-lethal consequences (i.e.…”

Contemporary and emerging fisheries in The Bahamas—Conservation and management challenges, achievements and future directions

“…These management decisions have been effective at protecting coastal species with limited home ranges (e.g., the reef shark, Carcharhinus perezi (Poey); Shipley et al., ), which exhibited no long‐term (1979–2013) decline in abundance (Edward Brooks , Cape Eleuthera Institute, unpublished data). Conversely, the abundance of transboundary and highly migratory species with pelagic components to their life history, for example the tiger shark, Galeocerdo cuvier (Péron & Lesueur), which is known to move seasonally between North Atlantic and Bahamian waters (Lea et al., ), declined 22% in the same period (Edward Brooks , Cape Eleuthera Institute, unpublished data).…”