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| Maintenance of Biological Diversity
In the Convention of Biological Diversity
the term biological diversity is defined as "the variability among
living organisms from all sources including, inter alia, terrestrial,
marine and other aquatic ecosystems and the ecological complexes of
which they are part; this includes diversity within species, between
species and of ecosystems".Researchers have not been able to agree
on a single explanation of biological diversity. It is generally accepted
that biological diversity (or biodiversity, as it is sometimes called)
is a hierarchical concept, where diversity is considered on several
levels, most commonly the genetic, species, and ecosystem levels. These
levels can be further split into smaller sections, if a finer resolution
is desired. The concept of hierarchical levels of biological diversity
is convenient in organizing information and in studying diversity, and
has been adopted worldwide. Conserving biological diversity on all levels
is more effective than directing all conservation efforts towards only
one level, such as species diversity. Although the marine component
of biological diversity is of immense importance to humankind, information
about the status of marine living resources and ecosystems is less complete
than that for terrestrial ecosystems. Oceans cover 71% of the world’s
surface. The whole ocean is capable of supporting life. However, this
life is unevenly distributed, with some areas having high species diversity
and productivity while other areas are much poorer. Coral reefs, for
example, are one of the most productive and diverse of all natural ecosystems. Species diversity Species diversity is the middle level
in the hierarchy of biological diversity. Species diversity is often
equated with biological diversity, although this is not the case. Species
diversity refers to the variety of species in a certain region, and
varies greatly among taxonomic groups and among geographic areas. In
general, there is a greater number of small species than large ones,
although the diversity of larger organisms is better known than that
of smaller ones. For example, there are many more species of insects
than species of sharks. Also, in the marine environment, the diversity
of plants is lower than the diversity of animals. Marine species diversity
is much higher in tropical regions than in temperate or arctic regions,
with such exceptions as kelps and starfishes, which are most diverse
in the cold waters of the Pacific Northwest U.S. and Canada. Within
the tropics, the Indo-Pacific region has much higher species diversity
than the Caribbean, because the Indo-Pacific, as an older ocean, has
had more time for speciation to take place.Species richness, or the
number of species within a certain area, is one of the most straightforward
ways to measure biological diversity. Counting the exact number of species
occurring in an area is a difficult task, however, because a majority
of the species are likely to be very small and difficult to identify
and count in the field. The uniqueness of an area may be assessed by
the number of endemic species found there. A species is endemic to a
particular area if it only occurs in that area and not elsewhere. The
degree of endemism is an indication of an area’s importance in
a wider context. Sites rich in endemic species can be seen as areas
of active speciation or refuges for relict species. From the point of
biodiversity conservation, it is important to identify areas with a
high number of endemic species. Ecosystem diversity Ecosystem diversity is the highest level
on the hierarchy of biological diversity. The composition, structure,
and function of ecosystems are the three main ways in which ecosystem
diversity is measured. Differing physical conditions favor different
communities of species. The concept of ecosystem encompasses both the
species composition of the communities and the physical structures that
the communities exist in. The interactions within and between species,
the ecology of the community, is also a part of ecosystem diversity,
and one of the ways in which ecosystems differ from one another. The
pathways of energy flow and proportions of organisms performing particular
functions also distinguish one ecosystem from another. For example,
coral reefs have high primary production by efficiently cycling the
available nutrients, while deep sea hydrothermal vent communities rely
on chemosynthesis instead of photosynthesis for primary production.
Ecosystem diversity is harder to measure than species or genetic diversity
because the boundaries of communities and ecosystems are often hard
to define. Measuring ecosystem diversity necessitates the use of a consistent
set of criteria to define communities and ecosystems.Ecosystem diversity
not only occurs between different ecosystems but also among similar
types of ecosystems. Wetlands in the Caribbean, for example are very
different from wetlands in Northern Europe. Even within the Wider Caribbean
region there are differences, where estuaries on a small, mountainous
island might differ greatly from an estuary on the Caribbean coast of
Central America. It is sometimes hard to classify marine ecosystems,
and no universally accepted classification system exists. The population,
food web, and community dynamics of marine ecosystems are not well understood,
although ecosystem diversity in the sea is high. Genetic diversity Genetic diversity is the lowest level
in the hierarchy of biological diversity, and it is the least studied.
Genetic diversity refers to the variation of genes within a species.
Each species consists of one or more populations of individuals. Individuals
within a population are more likely to breed with one another than with
the members of a different population. This is often due to proximity,
and to the fact that different populations often breed in different
locations. Green sea turtles, for example, return to the same nesting
beach they left as hatchlings to breed. Although there is some interbreeding
between members of populations using close-by nesting beaches, there
is virtually no chance of green turtles from Australia and Nicaragua
interbreeding. The time of breeding can also keep populations separate
in some cases. Because of the limited genetic mixing between populations,
they tend to diverge genetically over time. This happens because of
mutation, natural selection and genetic drift. Because of this divergence,
some populations have specific versions of genes (alleles) that are
not present in other populations, or alleles very rare in one population
may be abundant in another. This may be due to adaptations to local
environmental conditions. Like ecosystem diversity, genetic diversity
can be evaluated either between populations or within a population.
Within a given population, individuals posses different variations of
a particular gene. The process of evolution utilizes this genetic diversity,
where changing environmental conditions may favor certain alleles. Populations
with higher genetic diversity will likely have at least a few individuals
who will be able to withstand a particular environmental change, reproduce
successfully, and ensure the survival of the population. Because of
the certainty of changing environmental conditions in the future, it
is important that genetic diversity be conserved. Other types of biological diversity There are two complementary ways of looking at biological diversity that can be used along with the hierarchical approach. One is to consider the diversity of higher taxonomic groups, the phyla and the classes. The diversity of the higher taxonomic groups is much greater in the sea than it is on land or in fresh water. This is thought to be because the phyla originated in the sea and remain there, with only a small portion spreading to the land and to fresh water environments. Most of the species diversity on land comes from the phylum Arthropoda, and the members of its class Insecta outnumber the species in all other animal phyla. While Insecta are not numerous in the marine environment, many other phyla are either almost exclusively (sponges, bryozoans, coelenterates), or exclusively (comb jellies, echinoderms, lamp shells) marine. There is still much to be discovered about marine biological diversity, especially with very small planktonic organisms (picoplankton), small sized benthic organisms, and deep sea communities.Another way to look at biological diversity is to examine function. This can be done according to method of feeding, method of reproduction and the length of time to reach maturity. It is also possible to look at biochemical diversity. In ecosystems where there are a lot of sessile organisms and where the predation pressure is high (such as coral reefs) there is also likely to be a high diversity of defensive chemicals, which are of interest to the pharmaceutical industry.
The Wider Caribbean region contains a rich variety of complex ecosystems with a great abundance of plant and animal species, some of them endemic to the region. Along the coast of Belize is the second longest barrier reef in the world, and the longest one in the northern hemisphere. The number of endemic species is high when compared to the total number of species. For example, in Jamaica, the ratio of endemic to total species is 27:256 for breeding birds, 20:24 for lizards, 15:19 for frogs and toads, 82:579 for ferns, and 784:3000 for flowering plants. The Wider Caribbean region contains diverse and productive coastal and marine habitats. The region represents the greatest concentration of biodiversity in the Atlantic Ocean Basin. Because the nations in this region depend heavily on the health and the beauty of the natural world to generate income, the conservation of the region’s biological diversity is not only linked to social, cultural, and political conditions, but also to the economic realities of the region. Coral reefs, seagrass meadows and mangroves are among the best known marine and coastal ecosystems in the Wider Caribbean region and large contributors to the biodiversity of the region. Marine biodiversity data for the Wider Caribbean region has been collected from several sources and was published in 1996 in the UNEP and World Conservation Monitoring Centre publication, WCMC Biodiversity Series No4, The Diversity of the Seas: a regional approach. Some of the data is presented here. Caribbean Regional Sea: biodiversity data
where endemic = restricted to the region Caribbean Regional Sea: regional endemic species
In general, seagrass diversity is fairly low, with two species endemic to the region. The diversity of seagrasses and corals is lower in the Caribbean region than it is in the Indo-Pacific, although the Caribbean has the highest number of regionally endemic genera in the world. This is due to the geographic isolation of the Caribbean Sea from other major coral areas. The region has a high diversity of molluscs and crustaceans, but a low diversity of seabirds, as is the case in many tropical regions. All species of marine turtle, except for the flatback Natator depressus breed in the region. The critically endangered Kemp’s Ridley Lepidochelys kempii is confined to the region as a nesting species. Amongst sirenians, the West Indian Manatee Trichecus manatus is almost confined to the region, although its range extends into the northern part of the Southwest Atlantic Region.
The Caribbean Sea is bordered by 36 nations, including continental countries, island nations, and dependent territories. Some of these nations have large populations and industries while others are sparsely populated. At present, the responsibility for the region’s marine resources is divided between these 36 nations. There is a need for regional cooperation in resource management, considering that many of the resources and the stresses that are impacting them are transboundary in nature. Increasingly, ecosystems in the Wider Caribbean region are under heavy stress from human activities, and a number of unique ecosystems and habitats have been destroyed, and species exterminated. In the last 150 years, eight species of vertebrates have become extinct in Jamaica alone. More than 100 plant species, which are indigenous to Trinidad and Tobago may be threatened by extinction. Worldwide, human activities, directly and indirectly, are now the primary causes for changes in biodiversity. Approximately 50% of the human population lives in the coastal zone, and pressures exerted on the marine environment are increasing. Some of the main threats to biodiversity in the Wider Caribbean Region are habitat destruction due to coastal development and to the expansion in population and in tourism, pollution, overexploitation of living resources, including fisheries, sedimentation, and predation by introduced species. As a result, coral reefs, seagrasses and mangroves, among other coastal ecosystems, are under intense pressure, threatening biological diversity in the region.
Habitat destruction and alteration Habitat destruction and alteration is one of the leading causes for the loss of biodiversity. Because organisms are adapted to certain physical conditions and environments, altering these conditions will result in a change in the biological community. Physical destruction or alteration of marine and coastal environments includes the clearance of mangroves, construction activities, dredging, mining, and anchoring. Changing the structure of the environment results in simplifying, fragmenting (the breaking up of continuous ecosystems into fragments surrounded by unsuitable habitat), and eliminating the habitats of certain species. As a result, the functioning of entire ecosystems can be affected. The scale, intensity, duration, and timing of the physical alteration to the environment all determine its impact. Clearance of mangrove forests is a problem throughout the Wider Caribbean Region. Mangroves are cut down to for housing and tourism-related development, for the construction of roads and for the development of industry and mariculture. Clearing mangrove forests makes the coast more vulnerable to erosion, and destroys the habitat of many species. The nursery grounds of the juveniles of many commercially important fisheries species, such as lobster, will also be destroyed when mangroves are cut down. These species will, as adults, migrate to live on nearby coral reefs. Since mangroves buffer the nearshore marine environments from many land-based impacts, such as nutrients, pollution and sediments, the loss of these functions may result in a deteriorating quality of other nearby ecosystems. Of concern in the Wider Caribbean Region are construction-related activities, such as alteration to the coastline, beach mining and renourishment, dredging, and filling. All of these activities have considerable environmental impact. Shoreline structures, including piers, jetties and breakwaters, alter the patterns of sediment transport, preventing the renourishment of beaches downstream of this river of sand. A disruption in sediment transport can lead to the erosion of beaches and marshes. Beach sand mining, a common practice in the region, causes sedimentation, which has a negative impact on coral reefs and other marine ecosystems. Similarly, dredging not only physically alters marine ecosystems, but also causes the re-suspension of large amounts of sediment. Suspended sediments decrease water clarity and thus affect photosynthesis, stress corals and other suspension-feeders by making them expend energy in ridding themselves of sediment, and, in the most severe cases, smother the organisms themselves. Biodiversity of corals, other invertebrates, fish, and algae is reduced as a result. Other activities altering the physical environment and causing a reduction in biological diversity include trawling for shrimp, which disturbs the seabed and the associated benthic communities, resuspends sediments and causes turbidity currents. In areas that are heavily visited by recreational visitors and tourists, impact caused by divers, snorkellers and boat ancors can be considerable. Land based activities, such as logging, construction of roads and buildings, and agricultural practices not only have an impact at the site of the activity, but also in coastal and marine ecosystems some distance away. The increased siltation resulting from such activities can have serious effects on coral reefs, especially on those fringing the coastline. Siltation in general is one of the largest sources of coral reef degradation worldwide.
Overexploitation of living things Overexploitation of living resources is a serious problem at the current time because there are more people than ever utilizing limited resources, while technological advances have made it easier to exploit wild populations of animals. The sustainable use of species means that no more are taken than the species themselves can replace through reproduction. The Wider Caribbean Region includes a large number of countries of diverse social and economic status. Because of this, there are as wide a variety of fishing activities taking place (including industrial, artisanal and recreational) as there are approaches to management. Overexploitation, at its simplest, means that fish and other commercially valuable species are removed faster than they can reproduce. Main fisheries within the area are for small and large pelagic finfish, reef fishes, coastal demersal finfish, crustaceans and molluscs. Fisheries in the Wider Caribbean region are affected by fishing pressure. According to FAO’s 1994 assessment, just over 35% of stocks in the region were regarded as overexploited. This number includes stocks that were considered fully fished, overfished, depleted or recovering. The assessment does not include mollusc stocks, which may be significant considering the importance of conch for the fisheries of the region. Just under 60% of demersal stocks were overexploited and just under 70% of pelagic stocks. Crustacean stocks were not generally considered overexploited. However, these figures are only overall estimates, and the state of local stocks varies greatly. Generally, overexploiting the inshore reef fishery resources has led many countries to direct exploitation of offshore pelagic resources. These stocks tend to be highly migratory, and their management will in most cases require regional and international cooperation. Species, which mature slowly and produce few young are particularly vulnerable to overexploitation. Sea turtles, sharks, whales, manatees and sea birds fall into this category. Sea turtles, for example, may, in some cases, take up to 50 years to reach sexual maturity. High mortality from natural causes combined with human exploitation and loss of nesting beaches has put six out of seven species of sea turtle in danger of extinction. Many of the slow maturing species are also highly migratory, passing through the territorial waters and coastal areas of many countries. International cooperation is required to conserve the populations of such species. Most marine fishes and invertebrates making up the main fisheries species in the Wider Caribbean region reproduce early and in sufficient numbers to make sustainable use possible. However, even many of these species are now overexploited. According to FAO’s 1994 estimation, by-catches and discards worldwide total an estimated 18 to 40 million tonnes. This represented just over 25% of the annual estimated total catch. Shrimp fishing, an important fishery in the Wider Caribbean Region, produces the largest volume of discards, an estimated 9 million tonnes annually worldwide. FAO estimated that the Wider Caribbean Region has the highest percentage of discard of any of the major fishing areas, with nearly half of the catch believed to be discarded. Most of this is the by-catch of shrimp trawling, particularly in the Northern Gulf of Mexico. By-catches include marine mammals, sea turtles, seabirds, as well as finfishes and invertebrates. Dolphins are caught in pelagic drift nets, sea turtles in shrimp trawls, and diving seabirds in long-lines. Solutions to by-catches and discards include improving the selectivity of fishing gear and fishing methods. However, much of the research in by-catch elimination has been carried out in North America and Europe, and is not readily transferable to multi-species tropical fisheries. Tropical shrimp trawls still produce the highest rates of by-catch. Turtle excluder devices (TEDs) are now required by all countries exporting shrimp to the U.S. However, even with TEDs in place, the number of invertebrates and other by-catch is still high, and trawling has a serious impact on benthic habitats. Improved utilization of by-catch as a food source is a possibility, but the mortality of potentially threatened species and the capture of immature specimens remains a serious problem.
Pollution Pollution damages productive fisheries and viable tourism areas, and leads to reduced biological diversity. By straining the ecosystem, pollution removes sensitive species. Some pollutants are toxic or radioactive, and may not only have a direct impact on an organism, but can also be passed along the food chain. Other pollutants, such as nutrients, stimulate plant growth, which in a tropical marine environment may cause algae to overgrow coral reefs and seagrass meadows. Solid waste, including plastics, glass, metal, and other debris can be harmful to marine life. Plastics are known to cause widespread mortality in marine species through entanglement and ingestion. Sea turtles, for example, are known to die from ingesting plastic bags floating in the sea. Pollution may have a considerable impact on the state of the fisheries in an area. It may also affect biodiversity indirectly, by altering or destroying the habitat of a particular species. The impact can be particularly devastating in the case of an endangered or a threatened species. The Caribbean is one of the most heavily traversed seas worldwide, and pollution from transboundary and extra-regional activities is significant. These activities include the transport of oil through the region as well as shipping, which generate pollution in the form of bilge water and garbage dumped in the ocean. However, there is also a considerable amount of pollution that originates from within the region. Contaminants include sewage, solid waste leachate from landfills, industrial and agricultural run-off, and petroleum products. The article titled Land Based Sources of Marine Pollution in our Environmental Issues in the Caribbean section discusses pollution and its effects on the marine and coastal environments of the region in more detail. Several international treaties and conventions
are in place for the prevention of pollution. Pollution from
ship-based sources is regulated by the International Convention
for the Prevention of Pollution from Ships of 1973, which
was superseded by the 1978 Protocol (Marpol 73/78). Marpol
Annex IV regulates the discharge of sewage from ships, while
Annex V includes requirements for ships to control and prevent
dumping of garbage. Ports must provide facilities to receive
such wastes. The Wider Caribbean Region was designated as
a "special area" under the provisions of Annex V
of Marpol 73/78. This means that ships of any size are prohibited
from discharging any waste material except food waste, which
may be discharged 12 nautical miles (3 nautical miles in the
Wider Caribbean Region) from land. However, in order for the
special area designation to become effective, waste reception
facilities will have to be established in the ports of the
region. In practice, the establishment of waste reception
facilities creates a problem, especially for smaller nations.
The Marpol Treaty Annex V provides a legal framework to deal
with polluters. Unfortunately, many Caribbean countries are
not signatories to the Marpol Treaty. Introduction of alien species Alien species are organisms that have been transported by human activity into regions where they have not historically been found. Sometimes the introduction of an alien species is intentional, as is the case in activities such as agriculture and mariculture. Introductions may also be accidental, for example when organisms are carried from one port to another on ships. New organisms have arrived on many islands of the Caribbean either as stowaways onboard ships or in ship hulls. It is also common for organisms to move around in the ballast water carried in ship’s tanks to provide stability. Introduced species are responsible for many recorded species extinctions, especially on islands. In an isolated environment, an introduced species, having left behind its native predators, can rapidly outcompete the native species, which did not co-evolve with the newcomer. A number of alien species have been introduced to the Wider Caribbean region as a result of aquaculture projects, with negative impact to the native Caribbean biota. Although mariculture operations are usually viewed as having positive social and economic impacts, there is always the chance of accidental introduction of diseases and pathogens and the potential escape of the maricultured species into the wild. In most cases, there have been no experimental studies to verify the exact impacts caused by the introduced alien species. However, it has been documented that invasions can lead to fundamental changes in natural communities. One of the most significant impacts of introductions worldwide has been the increase of toxic phytoplankton blooms in coastal waters. Toxic dinoflagellate species or their cysts can be transported in ships ballast tanks from one nation to another. Toxic plankton blooms can have severe economic, social and human health impacts, often resulting in the closure of shellfishery operations. Despite the potential threats posed by introductions of alien species on natural communities, there are many advantages for initiating mariculture operations in order to create supplemental fisheries. Additionally, the release of large numbers of marine organisms by ballast water continues in most regions. There is a need for effective national and international measures and policies in order to mitigate and prevent the negative consequences of alien introductions. One such iniative, the UNCLOS framework, requires states to take measures to control the accidental or intentional introduction of exotic species.
Global climate change Oceans serve an important role as stabilizers of the global climate. They also function as sinks of atmospheric carbon dioxide (CO2). The living oceans control the atmospheric concentration of carbon dioxide and serve as biological pumps transporting the atmospheric carbon dioxide to the depths of the oceans. Tiny oceanic plants, the phytoplankton, take up dissolved carbon from the water column during photosynthesis. This CO2 originated in the atmosphere and was dissolved into the surface layer of the oceans. The phytoplankton will eventually either die or get eaten by animal plankton, the zooplankton. The dead remains will sink down from the surface waters. The carbon dioxide, which is incorporated into the tissues of the phytoplankton as carbon, will be removed to deeper waters or to the ocean floor in this manner. The processes of photosynthesis and decay pump carbon from the surface to the deep ocean. Any threat to the phytoplankton, such as climatically induced changes in ocean circulation patterns or increases in UV-B radiation at the sea surface, could dramatically reduce the efficiency of the biological carbon pump, and over time raise atmospheric Co2 levels, while reducing the productivity of the oceans. Sea level rise, which is a predicted effect of global warming is of special concern to low lying coastal areas and island nations. Water, when heated, expands causing a rise in sea levels. At the same time, the glaciers will be subjected to increased melting, another cause of rising seas. For the past century, sea levels have risen at a rate of 1 to 2 mm per year. Estimates of the rates of sea level rise under global warming vary according to the WMO-UNEP Intergovernmental Panel on Climate Change from a low estimate of 3 cm/decade to a high estimate of 10 cm/decade. The rates of sea level rise are not uniform and there are large localized variations. Coastal wetlands are likely to suffer the most impact from the predicted sea level rise. Coastal wetlands act as sediment traps stabilizing coastlines, storm protection, and as nursery grounds for many commercially important fisheries species. It has been debated whether coral growth can keep up with the predicted rates of sea level rise. If coral growth is not fast enough, large scale reef drowning may result. Rising seas will also put a stress on coastal ecosystems, threatening the habitats of the flora and fauna found there, causing an impact on both the biodiversity and the economy of the effected region. Coral bleaching has been increasingly observed in the tropical seas of the world, and could bring about massive ecological changes for coral reefs and other marine ecosystems. With the predicted rise in sea water temperatures caused by global warming, the incidences of coral bleaching would likely increase. Corals bleach when they lose the symbiotic algae living inside the tissues of the coral animal. These algae give coral colonies their characteristic yellowish or brownish color. When algae leave, the bleached corals appear white. Prolonged intervals at one to two degrees above normal summer temperatures can cause bleaching. Bleached coral colonies are alive, but not actively growing or reproducing. Bleached corals can recover if the sea water temperatures fall back to normal limits. However, if temperatures rise for even a few days to up to four degrees over normal limits, or if bleaching continues for long time periods, death of the coral colonies may result.
Conservation of biodiversity must take into
account the full range of causes for its loss, and promote
the opportunities that genes, species and ecosystems provide
for sustainable development. Efforts for the conservation
of biological diversity should ideally protect all levels
in the hierarchy of biological diversity: genes, species,
and ecosystems. The best way to maintain species is to maintain
their habitats. The conservation of biological diversity therefore
often involves efforts to prevent the degradation of key natural
ecosystems and to manage and protect them effectively. Another
component to the maintenance of biological diversity is restoring
lost species to their habitats and restoring the habitats
themselves. A part of this restoration may involve preserving
species in genebanks, zoos, and other facilities. Protection of critical habitats and ecosystems The most effective mechanism for conserving biological diversity is to prevent the destruction or degradation of habitat. Habitat loss and modification is the principal factor in the decline of global biodiversity. On a regional level, 76% of all the species, which are in danger of extinction are threatened by habitat loss or habitat modification. The primary causes of habitat loss in the Wider Caribbean Region are human development for settlement, tourism, and agriculture, as well as forest clearance and pollution. Monitoring habitats is fundamental to understanding the dynamics of biodiversity loss. Habitat monitoring includes several factors. These are recording changes in the geographical area of the habitat, recording changes in the condition or state of the habitat, and documenting habitat fragmentation. The problem of habitat monitoring is further complicated by the lack of an internationally accepted habitat or ecosystem classification system on a scale that is appropriate for national biodiversity management. Often, the classification system adopted is unique for the country, making regional and international comparisons difficult. There have been attempts to develop global biogeographic classification schemes, but these have been on large geographic scales and do not classify ecosystems on the scale that they are managed or monitored, such as coral reefs and seagrass beds. In addition, ecosystem mapping must take into account human impact on the landscape. Habitat maps should be used in conjunction with other environmental and natural resource maps in order to locate areas of interest for biodiversity ground surveys. Ecologically sensitive areas and habitats can be identified from a combination of existing maps and field surveys, and measures taken for their protection. Protected areas and reserves provide a way to protect critical habitats and ecosystems, and can allow for the maintenance of representative samples of natural habitats and biological diversity. The Specially Protected Areas and Wildlife (SPAW) protocol of the Cartagena Convention provides for a network of protected areas to conserve and restore regional ecosystems, including specific components such as coral reefs, mangroves and seagrass beds. In almost every Caribbean nation a number of ecologically important areas have been designated by national legislation as marine and coastal parks and protected areas. Most marine protected areas in the Caribbean are not exclusively marine, but constitute an extension of coastal protected areas. In addition to establishing new marine protected areas, efforts and resources should focus on the management of those already established. The nature and effectiveness of protected area systems vary greatly from one country to another. In many cases the parks lack adequate control mechanisms, and are inadequately protected from mounting pressure on their space and resources. The size of protected areas varies, too. Small reserves can often protect a large number of species, although large reserves are required to support viable populations of species that have large home ranges. Several regional initiatives to reduce environmental
impacts on coastal ecosystems are either in place or under
development. These include the Programme of Action for Sustainable
Development of Small Island Development States, which adopted
recommendations for implementing national, regional, and global
mechanisms for the sustainable management and protection of
coastal and marine resources and biological diversity. The
Caribbean Environmental Network (CEN) Project, focusing on
environmentally sustainable tourism, and the Land Based Sources
of Marine Pollution Protocol, a part of the Cartagena Convention,
are two examples of such mechanisms. On an international scale,
the Ramsar Convention (Convention on Wetlands of International
Importance) provides for strengthened protection of wetlands,
including shallow coastal and marine areas. The Ramsar convention
requires the acceding nation to designate at least one significant
wetland site that is sustainably managed. This provides international
recognition for the importance of the site and access to various
forms of scientific and technical cooperation. Restriction of commercial exploitation Fisheries regulation requires international measures in addition to national legislation and enforcement. Many fish species have large ranges extending into several countries’ exclusive economic zones. Both UN Conference on the Law of the Sea, UNCLOS, and the FAO Code of Conduct for Responsible Fisheries emphasize regional cooperation as key to successful implementation. International trade in endangered species is controlled by the CITES Convention. Some 118 countries are parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). CITES regulates international trade of all species listed in its Appendices (I, II and III). Appendix I lists species threatened with extinction which are or may be affected by trade. Trade in these species is banned except in exceptional circumstances. Appendix II lists species not yet threatened with extinction, but which may become so unless their trade is subject to strict international controls. Appendix III lists species, which any party identifies as subject to regulation within its jurisdiction to prevent or restrict exploitation, and which require the cooperation of other CITES parties in the control of international trade. The World Conservation Union (IUCN) assesses the conservation status of species worldwide and categorizes threatened species as endangered, vulnerable, rare, indeterminate, and insufficiently known. "Endangered" are those species that are in danger of extinction and whose survival is unlikely if the factors contributing to their condition persist. "Vulnerable" species are those which are believed likely to move into the "Endangered" category in the near future if the causal factors continue operating. Species, which have small populations worldwide that are not endangered or vulnerable, but are at risk, are grouped in the "Rare" category. The "Indeterminate" category contains species, which are known to be "Vulnerable" or "Rare" but where there is not enough information to say which of the three categories is appropriate. The "Insufficiently known" category contains taxa that are suspected but, because of lack of information, not definitely known to belong to one of the previous categories. The IUCN Red List of Threatened Animals contains listings of animals in all of these categories.
Control of genetic manipulation oc species and accidental introduction of alien species Research in biotechnology based upon genetic resources is becoming more popular, and is an important area of research for biodiversity conservation. However, there are risks involved in using and releasing living, modified organisms. The Convention on Biological Diversity urges the contracting parties as a group to consider the need for a "biosafety" protocol. In addition, establishing a procedure where advanced information is given to a country on living modified organisms when transferred from one country to another. Each country has the right to refuse the importation of certain potentially hazardous materials. Information should be provided on the nature of the materials and the possible consequences of their release. The United Nations Law of the Sea Convention (UNCLOS) Framework requires states to take measeures to control the accidental or intentional introduction of exotic species. The possible consequences of building canals from one body of water to another one, which is not naturally in contact with the first, should also be considered. Many marine species in the Mediterranean have been introduced there through the Suez Canal. The introduced species include shrimps, fishes, and jellyfish, and they have had an effect of depressing the populations of ecologically similar native species. The problem of release of marine organisms in ship ballast water continues without regulation in most areas, and will only stop when legislation prohibits the practice. Accidental introduction of alien species, with unpredictable consequences, will continue until effective national and international measures are in place.
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