Baseline assessment

A Report on the Status of the Coral Reefs of Bonaire 2003 with Advice on the Establishment of Fish Protection Areas

Bonaire has long been considered to have amongst the healthiest reefs of the Caribbean. However, at the 2002 Annual Meeting of Pew Fellows for Marine Conservation in Bonaire, several scientists with a long history of research on Bonaire’s coral reefs, expressed concern over the future of the island’s reefs. Specifically, they identified the decline in large predatory fish such as groupers as a noticeable change during the past decade. They suspected that this change resulted from increased fishing pressure on Bonaire’s reefs. They also suggested the Bonaire authorities take action to protect the reef-fish stocks. In response to those concerns, officials of the Bonaire Marine Park consulted with scientists and fishermen on Bonaire to explore the possibility of establishing fish protected areas (FPAs), as a way to protect the reef fish stocks. If FPAs improve both fish stocks and the condition of the coral reef, all stakeholders will profit. If fish stocks increased significantly in FPAs, a “spill over” of these fish to adjacent fished areas would be expected. Also, fish that perform important ecological functions could improve the quality of the coral reef ecosystem. Therefore, areas protected from fishing should have healthier coral reefs, which would also improve the island’s valuable ecotourism businesses. The Pew Fellows program funded a research project designed to identify potential FPAs. The Bonaire Marine Park authority, in consultation with the local fishing community would determine the location and size of the FPAs. To monitor the effects of fish protection areas so fishing impacts can be isolated from other factors (such as natural changes, shore-based impacts or effects of scuba divers), an equal number of similar reef sites were selected for study, with half closed to fishing while half remaining open (as “control” reefs). This report reviews the status and recent trends of coral reefs in the Caribbean and Bonaire. It identifies the key features of healthy reefs and how Bonaire’s reefs compares with those elsewhere in the Caribbean. The seven chapters go into scientific detail on factors contributing to the condition of Bonaire’s reefs as of March and April 2003. Special focus will be on factors that threaten reef health or are critical to reef resilience such as seaweed overgrowth, nutrient inputs from land and the ecology of juvenile corals. The report concludes with chapters on the socioeconomic effects of Bonaire’s coral reefs on the fishing and diving industries that depend on them.
Summary Results 2003: The Biological Status of the Coral Reefs of Bonaire & Socioeconomic Implications
 In March and April of 2003, teams of researchers studied the coral reefs of Bonaire to establish the baseline conditions that currently exist and against which trends can be determined and future changes from fish protection areas be assessed. Six study sites were chosen with advice from the Bonaire Marine Park. They represent a range of comparable reefs minimally affected by the 1999 Hurricane Lenny. The sites selected for this study were: Windsock, Plaza, Forest on Klein Bonaire, Scientifico, Barcadera and Karpata (Fig. 0.4). When feasible, parallel studies were conducted at 5 and 10 m depths, however, only the latter depth had fully developed reefs at all sites. The study was designed to quantify the patterns of abundance of the dominant reef organisms as well as to study the processes that control their abundances or threaten their stability. This was done to establish a baseline and to determine if significant differences exist among any of the study sites that would make them a poor choice as a FPA. We also examined some socioeconomic factors related to fishing and scuba diving activities if FPAs are established in Bonaire.

Date
2003
Data type
Research report
Theme
Research and monitoring
Report number
1
Geographic location
Bonaire

A baseline water quality assessment of the coastal reefs of Bonaire, Southern Caribbean

Bonaire is considered to harbor some of the best remaining coral reefs of the Caribbean, but faces multiple pressures including eutrophication. We measured multiple water quality indicators twice annually, from November 2011 to May 2013, at 11 locations at the west coast of Bonaire. This study resulted in 834 data points. DIN concentrations ranged from below quantification to 2.69 μmol/l, phosphate from below quantification to 0.16 μmol/l, and chlorophyll-a from 0.02 to 0.42 μg/l. Several indicators showed signs of eutrophication, with spatial and temporal effects. At southern and urban locations threshold levels of nitrogen were exceeded. This can be a result of brine leaching into sea from salt works and outflow of sewage water. Chlorophyll-a showed an increase in time, and phosphorus seemed to show a similar trend. These eutrophication indicators are likely to exceed threshold levels in near future if the observed trend continues. This is a cause for concern and action.

doi:10.1016/j.marpolbul.2014.06.054

 

Date
2014
Data type
Scientific article
Theme
Research and monitoring
Geographic location
Bonaire

Fisheries Baseline Assessment of Statia Marine Park, St Eustatius, Netherlands Antilles

Abstract:

St. Eustatius Marine Park was established in 1996 and became actively managed in 1997 to conserve and protect the marine environment. It consists of a general use area and two no-take reserves. The purpose of this study is to collect baseline data regarding fish stock populations within the marine park and its reserves in order to evaluate the success or otherwise of the environmental management strategies of the Marine Park. Questionnaires and semi-structured interviews were conducted with eleven fishermen on the island in order to learn more about the St. Eustatius fisheries and to examine changes that have taken place within the last ten years. A visual fish census of the coral reefs was also carried out at sixteen dive sites. The abundance and diversity of fish species were observed, along with length estimations in order to determine the standing stock and population size structure of specific species. The Southern Reserve of the Marine Park was observed as having the most abundant fish population and on average, between twenty and thirty species were observed at each of the dive sites surveyed. Blair’s Reef was identified as being the most diverse with over thirty-five species being observed. The diversity of the fish population in St. Eustatius has been proven to have increased dramatically in the last thirteen years, with the number of species currently present in the waters being on average 4.9 times greater than the number observed in 1992 at the same locations. When asked about the changes in the coral reefs and the fish populations over the past ten years, half of the fishermen said they saw no changes, while the other half said they had seen positive changes, citing more fish and less anchor damage. This clearly indicates that the establishment of the Marine Park nine years ago has been beneficial to the fish population within the local waters. 

Date
2006
Data type
Research report
Theme
Research and monitoring
Geographic location
St. Eustatius