Coral reefs

Geographic coupling of juvenile and adult habitat shapes spatial population dynamics of a coral reef fish

Abstract:

Marine spatial population dynamics are often addressed with a focus on larval dispersal, without taking into account movement behavior of individuals in later life stages. Processes occurring during demersal life stages may also drive spatial population dynamics if habitat quality is perceived differently by animals belonging to different life stages. In this study, we used a dual approach to understand how stage-structured habitat use and dispersal ability of adults shape the population of a marine fish species. Our study area and focal species provided us with the unique opportunity to study a closed island population. A spatial simulation model was used to estimate dispersal distances along a coral reef that surrounds the island, while contributions of different nursery bays were determined based on otolith stable isotope signatures of adult reef fish. The model showed that adult dispersal away from reef areas near nursery bays is limited. The results further show that different bays contributed unequally to the adult population on the coral reef, with productivity of juveniles in bay nursery habitat determining the degree of mixing among local populations on the reef and with one highly productive area contributing most to the island’s reef fish population. The contribution of the coral reef as a nursery habitat was minimal, even though it had a much larger surface area. These findings indicate that the geographic distribution of nursery areas and their productivity are important drivers for the spatial distribution patterns of adults on coral reefs. We suggest that limited dispersal of adults on reefs can lead to a source–sink structure in the adult stage, where reefs close to nurseries replenish more isolated reef areas. Understanding these spatial population dynamics of the demersal phase of marine animals is of major importance for the design and placement of marine reserves, as nursery areas contribute differently to maintain adult populations.

Date
2013
Data type
Scientific article
Theme
Research and monitoring
Journal
Geographic location
Curacao

Methods for Ecological Monitoring of Coral Reefs - A Resource for Managers - Version 1

The aim of this book is to help managers of coral reefs select appropriate ecological monitoring programs, protocols and methods for your coral reef management needs. This book was written in response to requests from coral reef managers for advice on monitoring, especially:

  • How monitoring can help management;
  • How to choose the best methods to suit your needs; and
  • The good and bad points and associated costs of a wide range of monitoring methods.

Monitoring can be specific or general. There are different management information needs for each coral reef area,
so monitoring programs must be designed to include a selection of protocols and methods to meet those needs.
The protocols and methods outlined in this book represent the ones most commonly used on coral reefs around the world. Our advice is to use the standard and frequently used methods to monitor your reefs because these have been extensively tested. Using standard methods also means that you will be able to compare the status of your coral reefs with other reefs at regional and global scales. 

Date
2004
Data type
Monitoring protocol
Theme
Research and monitoring

The current state of Cuaçao's Coral Reefs

Abstract:

The coral reefs of Curaçao represent one of the best reef systems left in the Caribbean at present. However, this does not mean that these reef systems are doing well. On the contrary: increased coastal development has resulted in pollution of near shore waters through the release of (untreated) sewage, nutrients and chemicals and overfishing represent some of the factors that have contributed to a near 20% decrease in the abundance of corals on the island in the last 25 years. Fish communities have been impacted similarly through uncontrolled fishing practices and Curacao presently holds an intermediate rank among Caribbean nations in terms of fish abundance. Coral reef systems provide the foundation for the island’s tourism and fishing industry and protect near shore developments against storms. Furthermore, healthy reefs prevent the rise of disease-causing bacteria in near shore waters preventing people, locals and visitors alike, from becoming ill. At the current rate of decline, coral reefs will have virtually disappeared around Curacao around the year 2060. Presently, it is estimated that Curaçaoan reefs bring in at least $1.6 million per kilometer per year through revenue from tourism, fishing and coastal protection alone. The decline of reefs will thus come with severe economic consequences for a recently formed country that finds itself still in a position to avert such catastrophe.

This report summarizes some of the information currently available to illustrate a potentially dark future for Curaçaoan reefs. Hopefully this report helps to illustrate some of the factors contributing to this decline so directed management strategies can be designed and put in place in order to maintain a unique aspect of Curaçao that makes it stand out in the region: its coral reefs. 

Date
2012
Data type
Research report
Theme
Research and monitoring
Geographic location
Curacao

Atlas of the Living Reefs of Curaçao and Bonaire (Netherlands Antilles)

The importance of reefs for man is multilateral and ranges from age-old functions, such as acting as a rampart preventing shore erosion, to modern mass tourism. Reefs offer man a source of income, actually providing subsistence for human populations. Food, often high quality protein , is the most important product . Reefs are also exploited for building material and for trade. Trade consists of living organisms such as aquarium fishes and other biota as shells, corals, etc. for jewelry and decoration purposes . A relatively new way of exploitation is by the tourist industry: snorkeling, diving and peripheral activities. Man grows more and more demanding in his use of the resources of the reef. Simultaneously, coastal development, urbanization and industrialization increase, obviously impairing reef communities . Reports on over-exploitation, pollution and mechanical destruction damaging reefs, are accumulating and show an increasing number of reefs suffering under the stress exerted on the shallow marine water habitat. Many reef areas are reported to deteriorate or be killed due to direct or indirect effects of tnan-induced disturbances

Opportunities for application of the atlas range widely in marine sciences, coastal planning and management. In the field of marine sciences the atlas will probably be most useful for studies in reef ecology, reef development, morphology and paleontology. Its value for coastal planning, management and conservation of the resources lies in immediate practical use.

This atlas contains 63 figures, 14 tables and 41 maps to give the reader an impression of what the coral reef ecosystems on the leeward coasts of Curaçao and Bonaire looked like in 1985. The leeward coasts of Curaçao (from Noordpunt to Oostpunt) and of Bonaire (from Malmok to the Willemstoren on the southern part) comprise approximately 66 resp. 56 km.

Precise habitat maps are drawn of this entire coastline and presented in fold-out maps in the back of the report.

[edit: a repetition of this study will presumably take place by Wageningen IMARES UR in the second half of 2013 to compare the two atlasses and pinpoint the changes that have occured over a little under 30 years.]

Date
1985
Data type
Research report
Theme
Research and monitoring
Report number
No. 117
Geographic location
Bonaire
Curacao

Can a thermally tolerant symbiont improve the future of Caribbean coral reefs?

The detrimental effect of climate change induced bleaching on Caribbean coral reefs has been widely documented in recent decades. Several studies have suggested that increases in the abundance of thermally tolerant endosymbionts may ameliorate the effect of climate change on reefs. Symbionts that confer tolerance to temperature also reduce the growth rate of their coral host. Here, we show, using a spatial ecosystem model, that an increment in the abundance of a thermally tolerant endosymbiont (D1a) is unlikely to ensure the persistence of Caribbean reefs, or to reduce their rate of decline, due to the concomitant reduction in growth rate under current thermal stress predictive scenarios. Furthermore, our results suggest that given the documented vital rates of D1a-dominated corals, increasing dominance of D1a in coral hosts may have a detrimental effect by reducing the resilience of Caribbean reefs, and preventing their long-term recovery. This is because Caribbean ecosystems appear to be highly sensitive to changes in the somatic growth rate of corals. Alternative outcomes might be expected in systems with different community-level dynamics such as reefs in the Indo-Pacific, where the ecological costs of reduced growth rate might be far smaller.

Date
2013
Data type
Scientific article
Theme
Research and monitoring

Report on the Economic Valuation of St. Eustatius’ Coral Reef Resources

Abstract:

The St. Eustatius National Marine Park conducted an Economic Valuation of St. Eustatius’ coral reef ecosystems in the fall of 2009. This attempted to put a monetary estimate on the coral reefs surrounding Statia. Coral Reefs are one of the island’s most valuable resources; they provide a livelihood through dive tourism and fishery and provide protection from large, damaging waves caused by hurricanes. In order to properly manage the coral reef ecosystem, an economic valuation is a useful tool to determine what exactly the monetary value of a coral reef is. With an attached value, better management decisions can be made to adequately protect this most precious of resources.

In order to complete the study four questionnaires were distributed. Two dealt specifically with fisheries, one with hotel accommodations, and one with dive tourism. Data was also provided by the Statia Tourism Office. Coral reefs have direct and indirect influences on a wide range of economic factors, and the generation of data was crucial to the successful completion of this study. Data was inputted into a computer program created by the World Resource Institute and which was adjusted by STENAPA to reflect Statia’s unique ecological and economic situation.

The findings of this study have outlined that Statia’s coral reef resources provide important goods and services to the economy of the island. The revenue that the resource is able to generate through coral reef associated tourism and fishery is approximately USD $11,200,454. Although this number is high, and highlights the importance of coral reefs to the island, it also suggests that there is an increased need for conservation, so that the value does not diminish. It is therefore in the best interest of Statia to incoroporate environmental economic data to: (1) Enforce land-use and development regulations in the coastal zone, (2) Enforce strict usage of anchorage areas, (3) Incorporate economic valuation into EIAs, (4) Include economic impacts in assessing fines for damages to reefs from activities such as anchoring in the reserves, oil spills etc, (5) Weigh revenues from a growing tourism industry against long-term economic losses from environmental impacts, (6) Evaluate distributional effects (“winners” and “losers”) of proposed coastal development projects, (7) Invest in Scientific Research, (8) Increase support from the private and public sector in the Marine Park Management Authority, STENAPA. 

Date
2010
Data type
Research report
Theme
Governance
Research and monitoring
Geographic location
St. Eustatius
Author

Status of Western Atlantic coral reefs in the Lesser Antilles

The Lesser Antilles include high volcanic islands with a limited marine shelf, and low coralline islands with a more extensive shelf. Withinthe group, reefs are affected to a greater or lesser degree by widely differing conditions of rainfall and runoff, hurricane damage, recreational use and fishing pressure. While degradation is reported in many areas, there are few long-term studies that quantify trends in reef status. In recent years there has been an increase in the number of management initiatives, and in the number of reef areas under active and effective management. 

Date
1999
Data type
Scientific article
Theme
Research and monitoring
Geographic location
Saba
St. Eustatius
St. Maarten

Inventory of Bonaire's coral reefs with particular attention to previously undescribed phenomena illustrating the ongoing decline of Bonaire’s reefs

General description 

New observations indicating undesirable trends on Bonairean reefs 

Unusual high abundances of the colonial tunicate Trididemnum on Bonaire’s Northwestern reefs

 Population explosions of coral and gorgonian eating snails 

Overgrowth of deeper reefs by the brown alga Lobophora variegata 

Increased abundance of coral‐destroying territorial damselfish 

Unprecedented predation on native fish by the invasive red lionfish 

 Historic factors negatively affecting the “health” of Bonaire’s reefs 

Current situation 

Unknown stressors for Bonaire’s reefs 

Conclusions

Date
2011
Data type
Other resources
Theme
Research and monitoring
Geographic location
Bonaire

Coastal region and small island papers 3: Saba, Netherlands Antilles

In comparison to other CARICOMP sites, the tiny island of Saba, in the Windward Islands arc of the Lesser Antilles, can be described as atypical in terms of its topography, geology, and marine environment. Saba has a small human population and anthropogenic impacts on the nearshore marine environment are limited. Sedimentation, dive tourism, and fishing are the three main impacts in coastal waters. Saba is devoid of mangrove stands; Thalassia seagrass beds and coral communities are restricted to a narrow shelf and offshore seamounts. CARICOMP sampling occurs only at one reef area on the leeward west coast. Physical oceanographic data are available for this site, and meteorological data are available for the island. Benthic composition is described based on CARICOMP surveys carried out to date and on a baseline monitoring program that was executed in 1993 as part of a study for the Saba Marine Park

Date
1998
Data type
Other resources
Geographic location
Saba
Author