Nassau grouper

The Nassau Grouper (Epinephelus striatus), is listed as ‘Vulnerable’ (IUCN, 2006). This species migrates to Northeast Point of Glover’s Reef Marine Reserve to congregate at the spawning aggregation site. The majority of Nassau groupers that spawn here are atoll resident.  Annual spawning aggregation surveys are conducted where counts are made by visual census techniques of species aggregating at the site, documenting the time and location. Physical measurements including salinity, currents, and air and water temperature are also taken.
There is a sharp distinction between juvenile and adult habitats. The juveniles are heavily reliant on:
• Shallow sea grass lagoon areas
• Patch reefs
• Mangroves (to a lesser extent)
• Sand and sparse algae (to a lesser extent)
…whilst habitat suitability for the adults focuses on:
• Dense/diffuse patch reefs,
• Forereef with dense massive & encrusting corals,
• Forereef with sparse massive & encrusting corals,
• Low relief spur & grove (females rest here during spawning),
• Deep reef/wall/escarpment
• Reef channels
Specific threats include: fishing at spawning site by hand lines (this species is very vulnerable to over fishing when spawning); spear fishing; and mangrove clearance. All threats to the health of the reef and sea grass beds are also indirect threats to the Nassau grouper (including anchoring, global warming, sewage, run-off, dredging).