Marine

The Sargasso Sea is a fundamentally important part of the world’s ocean, located within the North Atlantic sub-tropical gyre with its boundaries defined by the surrounding currents. It is the only sea without land boundaries with water depths ranging from the surface coral reefs of Bermuda to abyssal plains at 4500 m. The Sargasso Sea’s importance derives from the interdependent mix of its physical structure and properties, its ecosystems, its role in global scale ocean and earth system processes, its socio-economic and cultural values, and its role in global scientific research. Despite this, the Sargasso Sea is threatened by a range of human activities that either directly adversely impact it or have the potential to do so. Being open ocean, the Sargasso Sea is part of the High Seas, the area of ocean that covers nearly 50% of the earth’s surface but which is beyond the jurisdiction and responsibility of any national government, and as such it enjoys little protection. To promote the importance of the Sargasso Sea, the Sargasso Sea Alliance was created under the leadership of the Government of Bermuda in 2010. This report provides a summary of the scientific and other supporting evidence for the importance of the Sargasso Sea and is intended to develop international recognition of this; to start the process of establishing appropriate management and precautionary regimes within existing agreements; and to stimulate a wider debate on appropriate management and protection for the High Seas.

Nine reasons why the Sargasso Sea is important are described and discussed. It is a place of legend with a rich history of great importance to Bermuda; it has an iconic ecosystem based upon floating Sargassum, the world’s only holopelagic seaweed, hosting a rich and diverse community including ten endemic species; it provides essential habitat for nurturing a wide diversity of species many of which are endangered or threatened; it is the only breeding location for the threatened European and American eels; it lies within a large ocean gyre which concentrates pollutants and which has a variety of oceanographic processes that impact its productivity and species diversity; it plays a disproportionately large role in global ocean processes of carbon sequestration; it is of major importance for global scientific research and monitoring and is home to the world’s longest ocean time series of measurements; it has significant values to local and world-wide economies; and it is threatened by activities including over-fishing, pollution, shipping, and Sargassum harvesting.

Apart from over-fishing many of the threats are potential, with few direct causal relationships between specific activities and adverse impacts. But there is accumulative evidence that the Sargasso Sea is being adversely impacted by human activities, and with the possibility of new uses for Sargassum in the future, the lack of direct scientific evidence does not preclude international action through the established precautionary approach. The opportunity to recognise the importance of the Sargasso Sea and to develop and implement procedures to protect this iconic region and the wider High Seas should be taken before it is too late. 

The literature on the endemic flora and fauna of the Dutch Lesser Antilles is scattered and often difficult to find. An initial compilation amounts to 163 extant terrestrial and freshwater taxa (121 nominate species and 42 subspecies) and 58 marine taxa (all nominate species) which are either restricted to one or more of the ABC islands, or which otherwise have a limited geographical distribution in the Southern Caribbean (i.e. endemic). In addition, a total of 39 endemic fossil taxa are listed.

The breakdown for extant endemic terrestrial and freshwater species and subspecies is as follows: plants (22 sp.); arachnids and insects (40 sp. + 4 ssp.); freshwater and subterranean crustaceans (25 sp. + 3 ssp.); freshwater polycheats, flatworms, rotatoria (7 sp.); terrestrial gastropods (15 sp. + 5 ssp.); fresh- brackishwater fishes (2 sp. + 1 ssp.); reptiles (9 sp. + 3 ssp.); birds (22 ssp.); 4 mammals (1 sp. + 4 ssp.).

Marine endemism especially concerns marine gastropod mollusks, many of which show direct development or have short larval dispersive stages. Other marine taxa probably contain significant endemism as well but have not been included because of a lack of information.
 

Abstract:

My thesis research builds on the ‘movement’ to value nature. This movement as I call it started as early as 1970 with a theory to quantify and monetize nature (Hueting, 1970). References to the concept of ecosystem services date back to the mid 1960s and early 1970s (de Groot et al., 2002). A Phd research into the value of nature by De Groot (1992) emphasized the need to “ecologize” economic valuation of ecosystem services by integrating ecological information.

In 2005 the Millenium Ecosystem Assessment (MEA) report used the ecosystem services approach to highlight the importance and drivers of changes of ecosystem service delivery (MEA, 2005). The Economics of Ecosystem services and Biodiversity (TEEB) platform built on the framework of MEA, but specified ecosystems in underlying functions, processes and structures to “ecologize” economic benefits of biodiversity and costs of biodiversity losses (TEEB, 2010a).

Valuation of ecosystem services can be done at three levels, monetary, quantitative and qualitative. Qualitative describes benefits in a non-numerical scale, quantitative measures benefits and changes based on numerical data and monetary builds on quantitative value and attaches a monetary value (White et al., 2011). This research is a semi-quantitative analysis of the functional value of coral reef habitats on Bonaire to support ecosystem services. It is part of an economic valuation study of marine and terrestrial ecosystem services on Bonaire. The economic valuation study estimated a monetary value of selected ecosystem services. My research measured the functional value, defined as the ecological importance of a habitat, on an ordinal scale with four levels (0-3).

The TEEB theoretical framework was applied by studying the underlying ecological functions, processes and structures of coral reefs that determine the capacity to deliver coral reef ecosystem services through a literature review. The functional group approach was used as a measure of the importance of habitats based on the level of representation of fish and coral functional groups. The methodology to analyze the functional value was inspired by a study of Harborne (2006) that established the functional value of Caribbean coral reef, seagrass and mangrove habitats to ecosystem processes.

My research applied this method using Bonaire as case study and adapted the method to determine the functional value of habitats to ecosystem services instead of ecosystem processes. This way the study of Harborne has been taken a step further by making the link between the economic analysis focussing on ecosystem services and the ecological analysis focussing on ecosystem functioning. The other adaptations made were the spatial scale, the habitat types and the data collection method. Harborne determined the value by doing a meta-analysis of empirical literature on processes in ten coral reef, seagrass and mangrove habitat types.

For my research primary data of fish and benthic functional groups were collected at over hundred locations along the entire leeward coast of Bonaire to value just two coral reef habitat types.

Outcome of this research are matrices presenting relationships between socio-economic services and ecological functions, processes and fish and benthic species representing a functional role. Another outcome are maps presenting the functional value of each location to support twelve ecosystem services based on the primary data collected. These maps were analyzed taking into account resource use on Bonaire and show which area are of high importance for each service.

This research is innovative in its attempt to link the economic value of ecosystem services with an ecological value of habitats to support these ecosystem services. In addition the survey of benthic cover and fish biodiversity and abundance has not been done at such a large scale according to our knowledge since the mapping of Bonaire in 1985 (Van Duyl, 1985).

Abstract:

This report contains a study regarding the biodiversity of the Saba Bank, one of the three largest atolls in the world. All scientific and anecdotic evidence suggests that the area is a hot spot of biodiversity and one of the few areas in the Caribbean that is still in a relatively pristine condition. The atoll is likely also important as a source of larvae for other areas in the region because of its enormous dimensions and diverse habitats. Major damage however may already be inflicted by the anchoring of large oil tankers. More scientific research is necessary with regards to the damage inflicted by anchoring and to the sustainability of current fishing practices, but to date there is already sufficient data to call for strong protection of the Saba Bank as soon as possible.
Therefore, an application to the International Maritime Organization (IMO) to designate the Saba Bank as a Particularly Sensitive Sea Area (PSSA) in order to prevent possibly irreversible damage to the ecosystem and to enable sustainable protection of it’s vulnerable resources seems crucial and urgent.

This research is performed within ‘Beleidsondersteunend Onderzoek’ (BO-11), cluster NLP of LNV-programs.

Findings:

The main conclusion from this study is that the Saba Bank is a hot spot of biodiversity and one of the few
areas in the Caribbean that is still in a relatively pristine condition. The Bank is likely also important as a source of
larvae for other areas in the region because of its enormous dimensions and diverse habitats.

• Scientific evidence that the Saba Bank constitutes a major hot spot in marine biodiversity in the Caribbean region has strongly increased over the last couple of years and is now overwhelming.
• All studies to date express surprise and wonder at the number of different habitats and species within the Saba Bank.
• With limited sampling effort new species have already been found within the Bank and more are to be expected.
• The Bank is likely be one of the very few places in the Caribbean that as yet has largely escaped human related pressures and may still be considered as being in a relatively pristine condition.

There is to date already sufficient data to call for strong protection of the Saba Bank as soon as possible. Designating the Saba Bank as a
Particularly Sensitive Sea Area (PSSA) in order to prevent possibly irreversible damage to the ecosystem and to
enable sustainable protection of its vulnerable resources seems crucial and urgent.

Management Recommendations:

• Study the effects of fishing to ensure that it remains at a sustainable level.
• Draft and implement a management plan as soon as possible. At present anchoring outside the 12 miles zone is not regulated and anchor damage could be devastating to the whole ecosystem.
• Carry out more research about the ecological processes of the Saba Bank so as to protect it in the most effective way.