Between 1.5 and 2 million people worldwide are believed to keep marine aquaria. The trade which supplies this hobby with live marine animals is a global multi-million dollar industry, worth an estimated US$200-330 million annually, and oper- ating throughout the tropics. Ornamental marine species (corals, other invertebrates and fish) are collected and transported mainly from Southeast Asia, but also increasingly from several island nations in the Indian and Pacific Oceans, to consumers in the main destination markets: the United States, the European Union (EU) and, to a lesser extent, Japan.
Very few of the species in trade are exploited directly for other purposes, and there is little doubt that aquarium animals are the highest value-added product that can be harvested from a coral reef. If managed sustainably, the trade could support jobs in predominantly rural, low-income coastal communities and so provide strong economic incentives for coral reef conservation in regions where other options for generating revenue are limited. However, damaging techniques occasionally used to collect the animals, possible over-harvesting of some species and the high levels of mortality associated with inadequate handling and transport of sensitive living organisms undermine this potential, and continue to pose significant challenges to achieving sustainability. As a result the trade has seldom been free of controversy as traders try to generate a profit, conservationists try to avoid further decline in coral reefs also suffering from other pressures, and policy makers try to assemble a legislative framework that protects coral reefs without threatening a legitimate business activity or the incomes of communities engaged in aquarium fishing.
In the main, this debate has taken place without access to impartial and quantitative data on the trade and, with so many different viewpoints, achieving consensus on its impacts, and hence the identification of suitable responses, has been difficult. In 2000, the United Nations Environment Programme World Conservation Monitoring Centre (UNEP-WCMC), the Marine Aquarium Council (MAC) and members of various aquarium trade asso- ciations began, in collaboration, to address this need for better information and created the Global Marine Aquarium Database (GMAD). Trade data have been obtained from wholesale exporters and importers of marine aquarium organisms, most often through copies of trade invoices, integrated and standardized into quantitative, species-specific information which has been placed in the public domain: www.unep-wcmc.org/marine/GMAD. Fifty- eight companies, approximately one-fifth of the whole- salers in business, and four government management authorities have provided data to GMAD. In August 2003 the dataset contained 102,928 trade records (7.7 million imported and 9.4 million exported animals) covering a total of 2,393 species of fish, corals and invertebrates and spanning the years 1988 to 2003. These data have permitted the most accurate quantitative estimates to date of the size of the global trade in marine ornamental fish and corals, and the first ever estimates for invertebrates other than corals, a previously overlooked section of the industry.
A total of 1,471 species of fish are traded worldwide with the best estimate of annual global trade ranging between 20 and 24 million individuals. Damselfish (Pomacentridae) make up almost half of the trade, with species of angelfish (Pomacanthidae), surgeonfish (Acanthuridae), wrasses (Labridae), gobies (Gobiidae) and butterflyfish (Chaetodontidae) accounting for approximately another 25-30 per cent. The most traded species are the blue-green damselfish (Chromis viridis), the clown anemonefish (Amphiprion ocellaris), the whitetail dascyllus (Dascyllus aruanus), the sapphire devil (Chrysiptera cyanea) and the threespot dascyllus (Dascyllus trimaculatus). The ten most traded species account for about 36 per cent of all fish traded for the years 1997 to 2002. Trade data, correlated with aquarium suitability information, indicate that two species known not to acclimatize well to aquarium con- ditions are nonetheless very commonly traded. They are the
bluestreak cleaner wrasse (Labroides dimidiatus: GMAD records 87,000 worldwide imports of this species from 1997 to 2002) and the mandarin fish (Synchiropus splendidus: GMAD records 11,000 live individuals exported to the EU in the same period). Data further indicate that species characterized as ‘truly unsuitable’, mainly due to their restricted dietary requirements, such as the foureye butterflyfish (Chaetodon capistratus), the harlequin filefish (Oxymonacanthus longisrostris) and the Hawaiian cleaner wrasse (Labroides phtirophagus), are also commonly traded, albeit in lower numbers.
A total of 140 species of stony coral, nearly all scleractinians, are traded worldwide, with the best
estimate of annual global trade ranging between 11 and 12 million pieces. Although difficulties associated with accurate coral identification probably make species data less reliable for corals than for fish, it is clear that species in seven genera (Trachyphyllia, Euphyllia, Goniopora, Acropora, Plerogyra, Catalaphyllia) are the most popular, accounting for approximately 56 per cent of the live coral trade between 1988 and 2002. Sixty-one species of soft coral are also traded, amounting to close to 390,000 pieces per year. Sarcophyton spp. (leather/mushroom/ toadstool coral) and Dendronephthya spp. (carnation coral) are two of the most commonly traded species. However, whilst the biology of the former makes it a hardy, fast-growing and easily propagated species under aquarium conditions, Dendronephthya spp. usually die within a few weeks, mainly due to the fact that they lack photosynthetic symbionts and rely on filtering particles and nutrients in the water column for food.
More than 500 species of invertebrates (other than corals) are traded as marine ornamentals, though the lack of a standard taxonomy makes it difficult to arrive at a precise figure. The best estimate of global annual trade ranges between 9 and 10 million animals, mostly molluscs, shrimps and anemones. Two groups of cleaner shrimp, Lysmata spp. and Stenopus spp., and a group of anemones, Heteractis spp., account for approximately 15 per cent of all invertebrates traded.
Overall, there is a pressing need for basic information on the population dynamics and life history characteristics of organisms targeted by the ornamental trade. Combined with accurate trade data, such information is essential for making more informed decisions regarding the sustainable collection of marine ornamentals.
Other efforts needed to achieve sustainable management of the aquarium trade include the continued development and wider application of third-party certification, whereby the consumer is empowered to assist in reducing the environmental impacts of the trade by selectively purchasing specimens produced in an environmentally friendly manner. At the source country level, the implementation of measures such as quotas and size limits, and restricted access to the ornamental fishery through, for example, the use of permits and the establishment of areas closed to the fishery, are recommended where appropriate, though proper con- sultation is essential. Further research in developing mariculture protocols for raising commonly traded species in source countries, to take pressure off wild stocks and to avoid removing livelihoods from local communities, should also be promoted. To date, only one-fifth of giant clams are cultured, while only 1-10 per cent of fish and fewer than 1 per cent of coral species are capable of being captive bred. Even fewer species are bred in commercial quantities.