Assessment of the Coral Reefs of the Turks and Caicos Islands (Part 1: Stony Corals and Algae)

Major constituents of the benthic reef community (stony corals, algae) were assessed in 28 reefs on the Caicos, Turks and Mouchoir Banks. Living stony coral cover ranged from 8-28%, averaging 18% overall. Montastraea annularis and M. faveolata of “intermediate” sizes (cm) dominated all examined reefs. Acropora palmata and A. cervicornis were scarce. The most frequently recruiting scleractinians were Porites astreoides and Agaricia agaricites; Montastraea recruits were uncommon. Old partial-colony mortality (overall mean = 23%) was greater than recent partial-colony mortality (mean = 3%). Crustose coralline algae and turf algae were generally more abundant than macroalgae. Mouchoir Bank, with the most isolated reefs, was in relatively poor condition, which suggests that remoteness alone does not protect coral reefs

Sedimentation rates and geochemistry of the Atlantic and Indic Ocean of Late Miocene - Early Pliocene

Studies of the late Miocene-early Pliocene biogenic bloom typically have focused on high-productivity areas in the Indian and Pacific Oceans in order to achieve high resolution samples. Thus there is a paucity of information concerning whether the Atlantic Ocean, in general or low-productivity regions in all three basins experienced this bloom. This study measured the phosphorus mass accumulation rate (PMAR). in five cores from low-productivity regions of the Atlantic and Indian Oceans. All cores exhibit a peak in productivity 4-5.5 Ma, coincident with the Indo-Pacific bloom. This suggests that nutrients were not shifted away from low-productivity regions nor out of the Atlantic Ocean. Instead, it appears that the bloom was caused by an overall increase in nutrient flux into the world oceans. Four of the cores record the bloom's PMAR peak as bimodal, indicating a pulsed increase in phosphorus to the oceans. This suggests that there may have been multiple causes of the biogenic bloom

Status of the Reefs in the Cayman Islands

As with many of the reefs in the Caribbean, the reefs in the Caymans have been under continuous natural and anthropogenic stresses (80% of the corals on the walls were bleached in 1998). In June, 1999 the reefs around Little Cayman and Grand Cayman Islands were assessed using the AGRRA protocol at 33 sites. A total of 4521 corals in 330 transects, 1807 algal quadrats, and 341 fish transects were measured. Assessment and habitat data are presented in a GIS. The coral reefs of the two Cayman Islands appear to be in similar good condition but there are some differences. Differences include higher frequency and average cover of macroalgae and higher incidence of coral diseases on Little Cayman. Algal competition does not appear to be a problem for corals at most sites. Thirteen (87%) of the sites on Grand Cayman had standing dead coral and only 4 sites (22%) on Little Cayman. Recent coral mortality was twice as high on Grand Cayman as on Little Cayman (5.0% vs 2.1%). Coral recruitment was patchy, but present, mostly at low levels across the region. Live coral cover averaged 19.8 ± 3.3% on Grand Cayman and 23.2 ± 5.4% on Little Cayman. No old Acropora palmata stands occur, however, low density patchy new growth occurs frequently. The average abundance of fish was greater and the frequency of certain fish, especially grouper and snapper were up to eight times higher on Little Cayman. Grouper spawning aggregations are still harvested in the Cayman Islands