Profound ecological changes are occurring on coral reefs throughout the tropics, with marked coral cover losses and concomitant algal increases, particularly in the Caribbean region. Historical declines in the abundance of large Caribbean reef fishes likely reflect centuries of overexploitation. However, effects of drastic recent degradation of reef habitats on reef fish assemblages have yet to be established. By using meta-analysis, we analyzed time series of reef fish density obtained from 48 studies that include 318 reefs across the Caribbean and span the time period 1955-2007. Our analyses show that overall reef fish density has been declining significantly for more than a decade, at rates that are consistent across all subregions of the Caribbean basin (2.7% to 6.0% loss per year) and in three of six trophic groups. Changes in fish density over the past half-century are modest relative to concurrent changes in benthic cover on Caribbean reefs. However, the recent significant decline in overall fish abundance and its consistency across several trophic groups and among both fished and nonfished species indicate that Caribbean fishes have begun to respond negatively to habitat degradation.

The CARICOMP monitoring network gathered standardized data from 52 seagrass sampling stations at 22 sites (mostly Thalassia testudinum-dominated beds in reef systems) across the Wider Caribbean twice a year over the period 1993 to 2007 (and in some cases up to 2012). Wide variations in community total biomass (285 to >2000 g dry m−2) and annual foliar productivity of the dominant seagrass T. testudinum (<200 and >2000 g dry m−2) were found among sites. Solar-cycle related intra-annual variations in T. testudinum leaf productivity were detected at latitudes > 16°N. Hurricanes had little to no long-term effects on these well-developed seagrass communities, except for 1 station, where the vegetation was lost by burial below ∼1 m sand. At two sites (5 stations), the seagrass beds collapsed due to excessive grazing by turtles or sea-urchins (the latter in combination with human impact and storms). The low-cost methods of this regional-scale monitoring program were sufficient to detect long-term shifts in the communities, and fifteen (43%) out of 35 long-term monitoring stations (at 17 sites) showed trends in seagrass communities consistent with expected changes under environmental deterioration.

<span>Costa Rica has coral communities and reefs on the Caribbean coast and on the Pacific along the coast and off-shore islands. The Southern section of the Caribbean coast has fringing and patch reefs, carbonate banks, and an incipient algal ridge. The Pacific coast has coral communities, reefs and isolated coral colonies. Coral reefs have been seriously impacted in the last 30 years, mainly by sediments (Caribbean coast and some Pacific reefs) and by El Niño warming events (both coasts). Monitoring is being carried out at three sites on each coast. Both coasts suffered significant reductions in live coral cover in the 1980’s, but coral cover is now increasing in most sites. The government of Costa Rica is aware of the importance of coral reefs and marine environments in general, and in recent years decrees have been implemented (or are in the process of approval) to protect them, but limited resources endanger their proper management and conservation, including proper outreach to reef users and the general public.</span>

AbstrAct:The Miskitus Cays, on the Caribbean coast of Nicaragua, consist of eighty mangrove and two sand and gravel cays, surrounded by seagrass beds, octocoral gardens, patch reefs, reef crests, extended algae platforms, short reef walls, and two marginal reefs around the sand cays. Seventy sites were inspected and eighteen sites were selected for rapid assessments in order to determine the status of the coral reefs. Linear transects and the intercept point methods were used to determine the relative benthic cover, and the density, size and health of coral colonies was estimated following the AGRRA protocol. Water was highly turbid due to the shallowness of the reefs and high wave energy. Northwest reefs, closer to the Coco river mouth, were affected by terrestrial sediments and were overgrown by algae whereas storm damage was evident in the eastern reef crest fronts. In total, 39 stony coral species were found and 12 new species were reported for Cayos Miskitus. Mean live coral cover was high (43.4%), but it was still lower than the algae cover (54.2%). Mean coral diameter (59.7 cm) and height (4.2 cm) were high but total mortality (27.9%), bleaching (4%) and diseases (3%) were low. Reefs of Nicaragua are in the best condition of the Caribbean region of Central America but good management of the fisheries, the marine reserve, and the Coco river basin are urgent to maintain reef quality.

Isla del Caño is a marine protected area on the south Pacific coast of Costa Rica, surrounded by coral reefs and coral communities. The ecology of these coral reefs has been studied for over 20 years, but they have not been mapped. Maps are considered a great research, planning, management and monitoring tool. Medium to high resolution images (HyMap 2005 and Quickbird 2007 respectively) were processed and classified in order to test and compare their accuracy in producing a marine habitat map. Manta tow surveys were performed in the field for identification of 7 marine habitats 1. Coral community; 2. Coral reef; 3. Bed rock; 4. Sand; 5. Sand with boulders; 6. Sand with rodolyths; and 7. Deep water. The overall accuracy was slightly higher using Quickbird (87%) than using Hymap (60%), however the difference was not significant. The map produced using Quickbird was selected to represent the marine habitats of Isla del Caño. This map will help to analyze the adequate size and zoning of the marine protected area.

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<p>El aumento de la temperatura y el nivel del mar, entre otros signos de cambio climático, están afectando los patrones de distribución, alimentación, reproducción y migración de las tortugas marinas y muchos otros organismos que ya de por sí están bajo presión por actividades humanas destructivas a nivel mundial, y las hace aun más vulnerables. Costa Rica no es la excepción, sin embargo se estima que las consecuencias no serían iguales en todo su territorio. La interacción entre las placas tectónicas Coco y Caribe bajo la península de Nicoya es aparentemente la principal causa del aumento del nivel relativo del mar de 4 mm/año en esta región. Sin embargo, si el deshielo y el aumento del nivel del mar global se aceleran superando los efectos locales, como parece estar ocurriendo, se daría un aumento del nivel del mar geográficamente generalizado. Un aumento de 1 m en el nivel del mar en playa Grande, por ejemplo, implicaría un retroceso de la playa aproximado de 50 m tierra adentro. La playa e infraestructura en esa franja quedarían inmersas en el agua y serían erosionadas por el choque de la marea, y gran parte de la inundación ocurriría desde atrás, avanzando por la boca del estero Tamarindo, por los manglares que lo rodean, y otros terrenos adyacentes. Urge tomar medidas de mitigación y adaptación del cambio climático en cada localidad que reduzcan la vulnerabilidad e incrementen la resistencia y la resiliencia de los ecosistemas y sociedades humanas. El proyecto de conservación de tortugas marinas en playa Junquillal es un estudio de caso que ha generado y exportado lecciones aprendidas en el campo de la conservación comunitaria y la adaptación al cambio climático.</p>