Caribbean

The Caribbean Sea is home to a diversity of coastal habitats that support the installation of three rich and complex ecosystems - coral reefs, mangroves and seagrasses -. There are also other unique formations such as stromatolites or blue holes. Oceanographic and climatic conditions allow homogeneous throughout the Caribbean basin to form a unit in terms of flora and fauna. This unit does not exclude an exceptional biological diversity, including species endemic to the area, which give the coasts of the Caribbean countries an ecological, landscape and some science. Recognition on the international and regional importance of the Caribbean Sea but also its fragile marine environment has allowed the Caribbean to gain its status as a natural heritage.

In addition to the ecosystem services it render (fisheries, coastal protection ...), the Caribbean Sea is a definite asset in the development of tourism in the area by the seaside as well as, more recently, ecotourism. The latter is generally based on marine protected areas and should facilitate the sustainable development of islands.

From a case study, the Saba Marine Park, the objective of this study is to analyze the relationship between natural heritage and marine ecotourism, as well as economic, social and environmental development of these resources.

Western Atlantic species of the New World genus Pustulatirus Vermeij and Snyder, 2006 are revised. Types of previously named taxa are figured. Species recognized as valid include P. attenuata (Reeve, 1847), range uncertain; P. eppi (Melvill, 1891), Curagao; P. ogum (Petuch, 1979), northeastern Brazil; and P. virginensis (Abbott, 1958), Bahama Islands and eastern Caribbean Sea to Aruba. Latirus karinae Nowell-Usticke, 1969 is confirmed as ajunior subjective synonym of P. virginensis. Syrinx annulata Röding, 1798, treated as a Caribbean Pustulatirus by Vermeij and Snyder (2006), and Latirus annulatus Melvill, 1891 are regarded as species inquirenda. Three new species are described: P biocellatus, northeastern Brazil; P. utilaensis, Bay Islands, Honduras and northwestern Panamá; and P. watermanorum, Honduras continental shelf and offshore Colombian banks. Most western Atlantic Pustulatirus shells exhibit little intraspecific variability in morphology or color and occur within rather precise, well-defined ranges; an exception is P. virginensis, whose shells exhibit much variability in size, morphology and color.

In a survey of the bathyal echinoderms of the Bahama Islands region using manned submersibles, approximately 200 species of echinoderms were encountered and documented; 33 species were echinoids, most of them widespread in the general Caribbean area. Three species were found to exhibit covering behavior, the piling of debris on the upper surface of the body. Active covering is common in at least 20 species of shallow-water echinoids, but it has been reliably documented previously only once in deep-sea habitats. Images of covered deep-sea species, and other species of related interest, are provided. Some of the reasons adduced in the past for covering in shallow-water species, such as reduction of incident light intensity, physical camouflage, ballast in turbulent water, protection from desiccation, presumably do not apply in bathyal species. The main reasons for covering in deep, dark, environments are as yet unknown. Some covering behavior in the deep sea may be related to protection of the genital pores, ocular plates, or madreporite. Covering in some deep-sea species may also be merely a tactile reflex action, as some authors have suggested for shallow-water species.

Abstract

The importance of mangrove and seagrass lagoonal habitats as nursery areas for many reef-associated fish species is well established in the scientific literature. However, few studies have examined the relative use by nursery species of different sub-habitats within such systems. Here, we investigated fish community structure of a variety of interconnected sub-habitats of the tropical lagoon of Lac Bay in Bonaire, Dutch Caribbean. Visual census was used to test the degree to which these sub-habitats may differ in their use by fishes of different species and life stages. We quantitatively sampled the fish species abundance, composition, and size structures at a total of 162 sites distributed among nine different sub-habitats that are common to mangrove and seagrass ecosystems. Fish community variables differed consistently among sub-habitats and were mainly influenced by the presence of mangrove root structure or seagrass cover. Mangrove fringe sub-habitats were a premier habitat since multiple life stages of a variety of species showed highest densities and biomass there. Several reef fish species had a distribution pattern suggesting a unique stepwise post-settlement life cycle migration in which larger juveniles and/or subadults appear to move from the open bay environment (seagrass beds or bay mangrove fringe) to the interior mangrove fringes along mangrove pools before later departing to the adult habitat of the coral reef. In the case of the well-lit and well-circulated central bay sub-habitat, the limiting factor to fish abundance and diversity appeared to be the paucity of three-dimensional shelter due to the lack of Thalassia seagrass beds. In the warm and hypersaline backwaters, physiological tolerance limits were likely a key limiting factor. Long-term changes driven by mangrove expansion into this non-estuarine lagoon have been steadily reducing the net coverage of clear bay waters, while the surface of shallow, muddy, and hypersaline backwaters, unusable by key nursery reef fish species, has been increasing by an almost equal amount. Our study shows how fish density varies along the full gradient of sub-habitats found across a tropical bay to provide insight into the potential consequences for nursery habitat function when the availability and quality of these sub-habitats change in response to the long-term dynamic processes of mangrove land reclamation and climate change.

Abstract
Surveying subaqueous beach profiles and features beyond wading depths can be a costly process, requiring use of expensive equipment and boats. This paper describes the materials and methods of a simple, low-cost technique for underwater bathymetric surveying, herein named the diver depth-gauge profiling (DDGP) method. Although accuracy of depth data depends on the quality of the depth gauges used, it is commonly within 0.3 m. Data collection reliability was evaluated by repeated underwater beach profile surveys, and an example of its use in the Caribbean is provided. 

Abstract

Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3 m−2 yr−1. However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below ‘predecline’ levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.

ABSTRACT: Region-wide assessments of coral cover typically rely on meta-analyses of small- scale ecological studies which have combined different coral reef habitats. This is particularly problematic on forereefs where at least 2 habitats can be found; coral-based bioherms and colo- nized hardgrounds (hereafter Orbicella reefs and gorgonian plains), each with very different structure and scleractinian coral cover. Here, we quantify the degree to which the failure to differ- entiate forereef zones dominated by framework building corals, mainly Orbicella spp. (hereafter Orbicella reefs) from gorgonian plains can lead to biased assessments of coral cover. We also pro- vide a baseline of an extensive sample of Caribbean coral reefs in 2010−2012 for the 2 habitats within the forereef. Mean scleractinian coral cover (±SE) at Orbicella reefs was 24 ± 1.3%, more than double the coral cover found on the gorgonian plains (10 ± 1.6%). The difference in coral cover between habitats within the same geomorphological zone is consistent with those calculated from an independent dataset for the basin (Atlantic and Gulf Rapid Reef Assessment). Further- more, the average coral cover calculated for Caribbean Orbicella reefs was more than double the values previously reported for entire reefs in the region a decade ago (10%), which integrated data from different habitats, depths, time periods and surveyors. Differentiating between forereef habitats has provided a meaningful baseline of coral state, which allows for realistic targets for management in the Caribbean basin. 

Aim

Coral assemblages on Caribbean reefs have largely been considered to be biogeographically homogeneous at a regional scale. We reassess this in three taxa (corals, sponges and octocorals) using three community attributes with increasing levels of information (species richness, composition and relative abundance) across hierarchical spatial scales, and identify the key environmental drivers associated with this variation.

Location

Caribbean Basin.

Methods

We assessed reefs along 546 transects positioned within the same forereef habitat (Orbicella reef) in 11 countries, using a consistent methodology and surveyors. Spatial variability in richness, composition and relative abundance was assessed at four hierarchical spatial scales – transects (metres), sites (kilometres), areas (tens of kilometres) and regions (hundreds of kilometres) – using permutational multivariate analysis of variance (PERMANOVA). The relevance of contemporary environmental factors in explaining the observed spatial patterns was also assessed using PERMANOVA.

Results

Consistent with previous studies, species richness of coral assemblages, commonly the focus of biogeographical studies, showed little variance at large spatial scales. In contrast, species composition and relative abundance showed significant variability at regional scales. Coral, sponge and octocoral assemblages each varied independently across spatial scales. Rugosity and wave exposure were key drivers of the composition and relative abundance of coral and octocoral assemblages.

Main conclusions

Caribbean reef assemblages exhibit considerable biogeographical variability at broad spatial scales (hundreds of kilometres) when more responsive community attributes were used. However, the high degree of variability within sites (kilometres) highlights the relevance of local ecological drivers such as rugosity and wave exposure in structuring assemblages. The high levels of within-site variability that is not explained by environmental variables may suggest a previously unrealized contribution of anthropogenic disturbance operating at local scales throughout the region.

Baseline data on anthropogenic seafloor debris contamination in the year 2000 is provided for 24 submersible video transects at depths of 80-900 m, off the Dutch ABC-islands (Aruba, Bonaire, Curaçao), in the southeastern Caribbean Sea. In total, 202 objects were documented from a combined 21,184 m of transect, ranging from sandy lower island-slope to rocky upper island-slope habitat. Debris densities differed significantly with depth. Highest debris accumulation (0.459 items 100 m(-2) or 4590 items per km(2)) occurred at depths of 300-600 m on more shallow-sloping (20-30°) sand and silt bottoms. The overall average debris density was 0.27 objects per 100 m(2) (or 2700 items per km(2)), which is an order of magnitude higher than most other deepwater debris studies. What we describe may be representative for other small, populated, steep volcanic Caribbean islands. Food and beverage-related items were the single largest usage category identified (44% of objects; mostly glass beverage bottles).

Findings on Marine Turtles
·         Migration routes to and from nesting sites (typically index beaches) are variously known in the Caribbean, increasingly from satellite telemetry and studies of genetics. Without doubt the WWF priority areas are connected to each other, as well as to others in the Caribbean and to the high seas, especially the Sargasso Sea, through their shared responsibility for marine turtles during their different life stages.
·         Nesting habitat for marine turtles in the Caribbean are reasonably well know, although data is continually accruing from existing and new projects that monitor nesting activity. The imperative is to capture and share data in a meaningful way so as to enable comparison between sites and to permit the analysis of population trends.
·         There is a growing focus on in-water monitoring which helps to shed light on foraging sites. A number of parallel efforts by coral reef researchers to monitor ecosystems also provide valuable information on coral reef health and resilience to climate change in the region. While these studies are useful in highlighting overall declines in the coral reef ecosystems upon which marine turtles depend, there was found to be lack of similar efforts to monitor seagrass habitat for marine turtles, or  water  quality  monitoring  in  what  is  a  highly  populated  region  with  increasing  coastal development that generally lacks urban environmental infrastructure.
·         MPAs in the Caribbean have not specifically been designed as a network to protect endangered marine turtles in their different life stages and habitats. There is better coverage of nesting beaches via terrestrial protected areas than of foraging sites in marine protected areas (MPAs), which also reflects the reality of competing interests from fisheries, oil exploration and infrastructure development. Effective MPAs require adequate management capacity, and enhanced enforcement capacity is a top priority need among Caribbean MPAs.
·         Threats to marine turtles are extensive. The most common threats to nesting turtles shared by the priority areas are artificial lighting, beach erosion/accretion and pollution The most common threats to foraging/migrating turtles are fisheries entanglement, bycatch and pollution. Throughout the Caribbean it is evident that financial and human resources are a major challenge for governments, NGOs and communities in taking forward marine turtle conservation efforts.
 
Findings on Sharks
·         Information relevant to sharks in the Caribbean was found to be spread throughout a wide range and a large volume of literature. The disparate sources of shark information include reports from national scientific and fisheries divisions, from regional fisheries management organizations, from multilateral  agencies,  and  from  regional  and  international  academic  institutions.   Only  one publication was found to bring together regional shark information.
·         Consultation with key shark experts indicated that much is still unknown about sharks, even for the more common shallow water species. Still less is known about pelagic sharks and their movements into and through the eco-regions of the Caribbean.
·         Information on sharks was found to be unevenly distributed amongst the priority areas covered in this inventory. More extensive information on sharks was found to exist for non-priority areas of the Caribbean, such as Venezuela and the US, than for the priority areas. The inventory serves to highlight geographical gaps in knowledge about sharks in the Caribbean, for example in relation to Cuban sharks, and these geographical could guide further investigation.
·         Insufficient data exists to determine which shark species are of possible concern in the Caribbean. Also complicating the Indices of relative abundance were found to sometimes provide conflicting information on population trends.
·         Although sharks are highly migratory, information on shark movements in the Caribbean and the Sargasso Sea comes from only a handful of sources.
·         Some landings data exists for shark fisheries and some data exists on the incidental capture of sharks in other fisheries. However, making meaningful comparisons between datasets is a complex and time-consuming task which could be undertaken with a specialist partner such as a regional fisheries management organization or a researcher.
·         There is scope to seek further input on sharks from a number of knowledgeable experts who were willing to contribute but were unavailable for consultation in the timeframe of this inventory.
·         Some of the information that was compiled in the course of the inventory was found to be old and/or limited in its coverage. Expert consultation raised a number of doubts about key references such as IUCN classification of sharks. There is a fundamental need to validate the presence of sharks in the region and assess their population status. Recommended follow-up to this inventory could be key local informant interviews with fishers and relevant local experts in each of the priority areas about shark sightings, catch and bycatch.
·         A key step towards effective management of Caribbean Sharks would be a meeting of regional shark scientists and experts to share data, assess its application to conservation and sustainable use, and to develop a strategy for addressing significant gaps in knowledge. Such a meeting focused on Caribbean sharks has not yet been achieved.
 
Recommendations on GIS
·         Continue GIS data scoping and the collection of existing information from organisations working on similar initiatives. Invest in understanding existing governance frameworks and building partnerships for future collaboration with other regional fisheries management organisations, BINGOs (TNC and ICUN),  Universities  (UWI,  CERMES),  local  and  regional  NGOs  (see  Mahon  et  al.  2013  for  full Caribbean governance review), with a view to developing a data sharing agreement with key partners. This would enable continued sharing of GIS data collected and produced with others practitioners working the region.
·         Construct a Geodatabase that addresses WWF’s strategic priorities in the Caribbean region and which fills gaps in existing GIS information for these priorities. This could provide a valuable spatial synthesis of several types of information relevant to the priority areas.
·         The largest GIS data gap is in relation to sharks. There are a number of studies on sharks (i.e. NOAA fisheries observer boats, Fisheries Division’s datasets) but this data needs to be compiled and GIS data produced, which requires more significant effort than was possible within the scope of this inventory.
·         There are also opportunities to improve GIS data related to marine turtles. Turtle migration is an example of this. There are multiple initiatives by various different turtle conservation organisations and academic institutions that are tracking the migrations of marine turtles in the region, especially by satellite.  GIS data from satellite tracking from various locations in the region exists, but it has never been compiled at the regional level for large scale analysis of marine turtle migration. This task could be usefully undertaken in future, ideally in conjunction with the WIDECAST network.
·         We note that some marine turtle data used in GIS are dynamic rather than static in nature and in the interests of data integrity they would benefit from updating. For example, new information is constantly becoming available from nesting monitoring activities, both new from new projects and the ongoing activities of longer term projects. There have also been discoveries of marine turtle aggregations at foraging sites, providing new data to input to GIS. Threats to marine turtles across the region are emerging and changing, for example in relation to tourism development, and creative approaches to GIS representation of this information could be developed to assist with monitoring impacts on population status and trends.
·         In  the  course  of  this  inventory  we  explored  some  new  approaches  to  mapping  marine  turtle populations   and   trends   with   the   aim   of   assisting   interpretation   and   enhancing   strategy development. The sample maps are based on data from Bonaire and the Guianas only, since comparable datasets were either missing for the other priority areas or could not be provided in the timeframe of the inventory.  There is potential to work further with WWF on the development of new GIS layers that directly feed into the strategy development process.