Map of Western Caribbean region, including survey sites 2005-2006 and
hurricane Wilman in 2005 (NOAA-MMHC). Reserevs in white bullets
and non-reserves in bold bullets. Sites from North to south:
Cozumel reefs, Akumal reefs, Chinchorro Bank and Hcalak reefs.
Species Richness and Community Structure of the Yucatan Marine Reserve Before and After 2005 Hurricane Season
Gustavo A. Paredes
We traveled to the Yucatan Peninsula in November of 2006 and located three survey sites in the Akumal town area (see map). Data on the abundance of fish, macroalgae, corals, and other invertebrates were collected at 15 meters depth. We attempted to collect data from shallow reefs (5 meters), but the reef structure at these sites develops below 7 meters so we decided to focus only at 15 meters. We compared data collected before and after hurricanes inside and outside reserves (table 1). Logistic and budget constrains did not allow us to re-survey Cozumel, but we were able to carry out the comparison using other monitoring data available. Although, the data are difficult to compare at a specific resolution, it is evident that the Cozumel reefs (reserve) were largely affected by the hurricanes in 2005 and are different from those in Akumal (non-protected). Coral cover remained similar before and after the hurricanes in the un-protected reefs; however, the Cozumel reserve suffered a significant decline in coral cover. This decline could be explained by the distance of the reefs from the hurricane (see map). Hurricane Wilma was the strongest to hit Cozumel with a 65 Km radius and up to 220 km/hr wind speed. The pre-hurricane coral community diversity was higher inside Cozumel reserve but after the hurricane diversity scores inside the reserve were more similar to those of the non-protected areas. The impact of the hurricanes in 2005 seems to have had a significant effect on the fish community as well. Evidently, pre-hurricane fish abundance was much higher inside Cozumel. Our data and that of other monitoring programs indicate that the differences in abundance of fish after the hurricane are less remarkable (table 1) than those observed for the corals. Divers visiting the area after the hurricanes reported that the fish community had diminished especially large groupers, as well as sea turtles. Akumal and Cozumel reefs may not recover unless immediate conservation actions take place (i.e. active restoration/marine reserves). Generally, non-protected reefs have less opportunity to recover from both natural and anthropogenic sources of disturbance than do reefs inside reserves. However our results suggest that hurricanes can alter the situation as occurred for the Cozumel reefs in 2005. Hurricane frequency in this area is among the highest in the Caribbean (NOAA, National Hurricane Center 2006) for that reason it is important to manage all coral reef sites, so we can assure that these events do not destroy all the progress made in a unique reserve.
The local NGO s are making a large effort to establish the Akumal reefs as a new marine reserve. We will provide the baseline data upon which it will be possible to evaluate the progress of the conservation actions on these coral reef sites. Data collected from 2004 to 2006 are being processed as part of a larger effort to understand the health of Caribbean coral reefs from a regional ecosystem perspective. Further analysis will be published in several peer reviewed publications as part of a dissertation project.