Beach environments are considered nutrient poor systems that support limited abundances of life due to the lack of attainable nutrients. Since the surrounding environment is nutrient limited, plants and organisms residing in sandy beach communities take advantage of available nutrients whenever possible, for example, nests laid on the beach. This study assessed whether nesting hawksbill sea turtles (Eretmochelys imbricata) are transporters of nutrients from ocean systems to nutrient-poor beaches of Bonaire, N.A. It was hypothesized that nitrogen (N) and phosphorus (P) levels would be elevated, infaunal organisms would be more abundant, and plant cover would be higher in nest plots compared to areas without nests. To determine the input of nutrients from nesting and the potential effects of nutrient enrichment on the plants and infauna, five experimental arrays, including nest, mechanically disturbed (no nutrient addition), and undisturbed treatments were sampled from September to October 2009 on Klein Bonaire. Five days following hatching events, sediment cores were taken to assess concentrations of N and P, as well as to determine the abundance of infauna. Plant percent cover was also determined for each plot. Nutrients did not differ significantly among plot type, with both N and P consistently at low concentrations. For all nest plots, 2.5 X more taxonomic groups, including known predators, were detected than in undisturbed or mechanically disturbed plots. No plants were found in any plot type for the duration of the study. This study suggests that hawksbill sea turtle nests are not strong drivers of coastal community structure in Bonaire. It is believed that the CaCO3 composition of the sand and the limestone base of the island do not allow for nutrient retention and thus excess nutrients are not available for exploitation by beach plants or infauna.
Cleaner shrimp are commonly found throughout Caribbean coral reefs and can effectively reduce parasite loads on reef fish resulting in increased fitness of local reef fish populations. The marine cleaner shrimp, Periclemenes pedersoni, most commonly inhabits two coral reef anemones, Condylactis gigantea or Bartholomea annulata, which have different distribution patterns on reefs. C. gigantea resides on hard or rocky substrates with greater relief, whereas B. annulata lives on muddy, sandy substrates or crevices with less relief. Past studies have been done on cleaning by P. pedersoni, yet no research has been done on the effects the differing host anemones may have on cleaning interactions. Using 12 min observation periods between 13:00 -17:00 h on the fringing reef in Bonaire, number of P. pedersoni shrimp, number of clients, species of clients, and time cleaned per client were recorded for C. gigantea and B. annulata anemone cleaning stations. When compared to B. annulata, C. gigantea had significantly more P. pedersoni shrimp, which cleaned a significantly greater number of client fishes. Greater species richness of clients was observed visiting C. gigantea than B. annulata cleaning stations, however there was no difference in time spent cleaning per client. Although protected in Bonaire, aquarium trade collection of C. gigantea throughout the rest of the Caribbean may result in an overall reduction in the number of cleaning interactions occurring on the reef, potentially having detrimental effects on the health of local fish populations.
This student research was retrieved from Physis: Journal of Marine Science IX (Spring 2011)19: 31-37 from CIEE Bonaire.
Bioluminescence is a cold-light produced by chemical reactions and has been observed in over 90% of marine organisms. The largely speculated adaptive significance behind bioluminescent activity includes defense against predators, prey distraction, and communication. Bioluminescent photosynthetic dinoflagellates play a major role in the ocean’s primary production. Daily vertical migrations (DVMs) through the water column are phototactic movements, where photosynthetic dinoflagellates return to the surface during daylight to photosynthesize. It was hypothesized that dinoflagellates migrate to the surface in daylight and to depth (4 m) in darkness. It was also hypothesized that chemically provoked luminescent activity would be greater after prolonged exposure to daylight rather than darkness. Samples were collected at am and pm intervals using a 30 cm diameter plankton tow with 20 µm netting. Density of dinoflagellates were estimated under a compound microscope using a Neubauer-improved haemocytometer. Luminescent assays were performed by adding 5% acetic acid to the samples and timing the duration of luminescence in s. A two-way ANOVA with depth and time as factors revealed a significant interaction: at night 4 m density was significantly higher than 0 m density, and in the morning 0 m density was significantly higher than 4 m density. Luminescent activity in the morning was significantly higher than in the evening. A DVM of bioluminescent dinoflagellates was exhibited as a result of a phototactic movement. This study aimed to understand the relatively unknown bioluminescent dinoflagellate activity of one shallow coastal area in Bonaire, Dutch Caribbean.
A coral is made up of key associations between endosymbiotic zooxanthellae, protists, bacteria, archaea, viruses, and fungi. These microbe-coral interactions can be very beneficial, some associations providing key functions in reproduction, nutrition, and antimicrobial protection. However, as a coral becomes thermally stressed, the ability to regulate microbe growth in its surface mucus layer becomes diminished and opportunistic pathogens are able to colonize. Corals may be able to adapt for the changing reef ecosystem by selecting for more beneficial associations: one of the facets of the coral probiotic hypothesis. The invasive azooxanthellate coral Tubastraea coccinea is able to colonize very shallow, hot and turbid areas that are not favorable for settlement by other species. However, not much is known about T. coccinea other than its invasive nature in the Caribbean. The purpose of this investigation was to determine if the surface microbial communities of T. coccinea are one of the factors aiding its survival. Culturing on Thiosulfate Citrate Bile Salt plates was used to visualize and compare the overall culturable Vibrio spp. communities present in T. coccinea and other widespread shallow corals. At each site, the numbers of Vibrio spp. were not significantly different between the three species, but numbers of a gram-positive bacteria, Enterococcus spp., were found to be significantly higher in T. coccinea.
The transition in the Caribbean Sea from coral dominated reefs to algal dominated reefs poses a serious risk to the current existing community. Current research suggests that algal communities will follow a predictable pattern of growth and succession based on the environmental conditions of the community. Depth of the coral head hosting the community and location on the coral head may have a role in succession. This study was conducted on a fringing reef on the leeward side of the island of Bonaire, DC in March of 2014. Algal communities were sampled at two locations on coral heads: just below the livecoral/dead coral interface and between 10 and 30 cm below the first sample. Analysis of genera richness and mass percent of algal divisions were not found to be correlated with depth for all algal divisions. However, richness of Rhodophyta genera was shown to be different between sampling locations on the same coral head and mass percent of Chlorophyta genera was shown to be negatively correlated with distance between sampling locations. The lack of variation found among many of the samples suggests that depth and sampling location on a coral head are largely unimportant in determining the make-up of an algal community, except the aforementioned relationships. Within the framework of creating a predictive model for algal succession, depth and community location on the coral head are components, but more work is needed. The creation of a predictive model will let reef managers forecast future threats and mitigate potential catastrophes.
This student research was retrieved from Physis: Journal of Marine Science XV (Spring 2014)19: 15-20 from CIEE Bonaire.
The strategic location of small islands in the Caribbean, close to the United States of America (USA), and their historical trade roots as former colonies of Europe make them an interesting business environment. Small islands' eagerness for economic development and their limited governance capacity often result in an unequal relationship between multinational private parties and small islands' policy actors, especially in regard to environmental management. This is also observed at St. Eustatius, a small Caribbean island that hosts a crucial oil storage and transshipment terminal that compromises the environmental state of the small island. However, in 2010, St. Eustatius (Statia) became part of the Netherlands, which significantly changed the responsibilities related to environmental management. Bringing the environmental state back in reversed existing power relations. To analyze these changing power dynamics, we apply the new social scientific concept of marine community, which encompasses a user community and a policy community and shows the different interests and power dynamics within and between them. While governance of the oil terminal used to be determined by structural power in the user community on behalf of NuStar, it currently relies on the structural power of the Dutch Ministry of Infrastructure and Environment (I&E) in the policy community. In theory, structural power to bring the environmental state back in would be beneficial for governance. In practice, however, this is challenging because a small island environmental state is different from the environmental state in countries in Western societies. Although the Dutch Ministry has structural power, the way it relates to others (dispositional power) and uses resources (relational power) should be better adapted to the needs and characteristics of small island environmental states such as Statia.