Collectors for the aquarium trade function as a peculiar and unprecedented type of generalist predator that targets both abundant and rare species. Until now a detailed study which quantifies the aquarium trade of marine animals had not been performed.
The international trade in colorful marine organisms from coral reefs has become big business over the past 15 years. New lighting and filtration technology enabled hobbyists to set up saltwater aquariums at home, and the popular 2003 movie "Finding Nemo" helped to also increase demand for clownfish and home reef aquariums.
The investigation was performed by Dr. Andrew Rhyne of Roger Williams University, Department of Biology and Marine Biology. The article, published in the journal PLoS ONE
, found that fishes comprising 1,802 species from 125 families were imported into the United States over a yearlong study period. Previous estimates of diversity based on government import forms were 22 percent lower. According to the federal Fish and Wildlife Service, one million of the world's 1.5 million aquarium hobbyists live in the United States, and Americans buy more than half of all marine aquarium fish sold globally.
Coral reef fish imported to the United States for saltwater aquariums are more diverse yet less numerous than previously thought. The most recent estimates suggest that the marine aquarium trade targets over 150 species of stony corals, hundreds of species of non-coral invertebrates, and at least 1,472 reef fish species from 50 families. Since 1990, the aquarium trade has seen a shift in consumer preference from fish-only aquariums to miniature reef ecosystems. Because of this, collectors now draw upon the full suite of coral reef biodiversity to supply aesthetic and life-support aquarium services.
Until now, little has been known about these imports. To gather hard data, Dr. Rhyne recruited a team of students to examine more than 8,000 shipment declarations and corresponding invoices provided by the National Oceanic and Atmospheric Administration and the Fish and Wildlife Service dating from May 2004 to May 2005.
The study raises flags on how ornamental marine fish imports are monitored. It was found that there are large error rates on import declaration form (a synopsis of the invoice) compared to what was actually invoiced making it difficult to determine the exact number of marine organisms imported.
The current tracking system maintained by the Fish and Wildlife Service tracks shipments based on the requirements set under the international treaty known as CITES, the Convention on International Trade in Endangered Species. However, CITES listed species comprise a small portion of the total ornamental aquatic animal trade, (namely stony corals, giant clams, and seahorses). Non-CITES-listed fish and invertebrate species are only listed with general codes, so the data do not contain information on volume, diversity of species, or trade pathways.
New tracking systems are needed to provide industry, governments, and biologists with information to monitor and manage the marine aquarium wildlife trade.