[Coral-List] Freeing Nemo: Aquarium owners releasing non-native fish could endanger marine ecosystems

Thu Apr 8 20:05:30 EDT 2004

> http://www.eurekalert.org/pub_releases/2004-04/uow-fna040704.php 
> Contact: Sandra Hines shines at u.washington.edu 
> <mailto:shines at u.washington.edu>
> 206-543-2580
> University of Washington <http://www.washington.edu/>
>
>
>   Freeing Nemo: Aquarium owners releasing non-native fish could
>   endanger marine ecosystems
>
> Flushing your pet tropical fish to set it free is a bad idea. So is 
> releasing it at the beach. Intentional and unintentional aquarium 
> releases have been a leading cause of freshwater fish invasions, but 
> now researchers from the University of Washington and the Reef 
> Environmental Education Foundation have found 16 non-native species of 
> fish - apparently set free from home aquariums - in ocean waters off 
> the southeast coast of Florida.
>
> This is an unprecedented number of non-native marine fish in a 
> concentrated geographic area, says Brice Semmens, a UW doctoral 
> student in biology and lead author of a paper published in the journal 
> Marine Ecology Progress Series.
>
> Using data on the aquarium trade and shipping traffic, the study is 
> the first to convincingly demonstrate that well-meaning pet owners can 
> cause a "hot spot" of non-native tropical marine fish, Semmens says. 
> The 16 species were found in 32 different locales along the coast of 
> Broward and Palm Beach counties and in the upper Florida Keys. Some 
> were in the Florida Keys National Marine Sanctuary.
>
> Most of the species were seen at more than one place meaning more than 
> just a few aquariums have been dumped, Semmens says. It is not clear 
> which, if any, of the non-natives have established breeding 
> populations, he said.
>
> The more times a species is released, however, the greater the chance 
> of establishment, says Walt Courtenay, fisheries biologist with the 
> U.S. Geological Survey in Gainesville, Fla., who is known around the 
> world for his expertise on exotic fishes. He is not a co-author of the 
> published paper.
>
> "Typically, I'd say aquarium owners are more concerned with the status 
> of our marine ecosystems than the general public is, yet many appear 
> unaware of the potential pitfalls of releasing pets into the wild," 
> Semmens says.
>
> The study relied on information submitted by volunteer divers and 
> snorkelers through the Exotic Species Sighting Program of the Reef 
> Environmental Education Foundation, or REEF, based in Key Largo, Fla. 
> Sightings were confirmed with photographs, video or corroboration by 
> other divers.
>
> The introduced species are native to the tropical western Pacific 
> and/or Red Sea. Emperor angelfish, with their blue masks and bodies 
> striped in blue and gold, were the most commonly sighted non-native 
> species and are imported by the aquarium industry in relatively large 
> numbers. Indeed, the researchers found a compelling correlation 
> between how commonly ornamental marine species are imported and how 
> often they were sighted. Another commonly sighted non-native was 
> yellow tang, a bright yellow oval fish that is the most commonly 
> imported species of the U.S. aquarium trade.
>
> In contrast, Semmens says it is unlikely the exotics arrived in the 
> ballast water of ships. If the fish were being introduced through ship 
> ballast, one would expect the native ranges of the fish to correlate 
> to where the ballast water comes from. Analyzing data on shipping 
> traffic to Florida ports, Semmens and his co-authors found no support 
> for this correlation.
>
> While only a small number of introduced species might have devastating 
> impacts, scientists are unable to predict which species will be 
> destructive. The largest set of intentionally released marine fish was 
> carried out in temperate coastal and inland seas of Russia in the 20th 
> century. Sixteen species became established, with ecologically and 
> economically devastating results, including harm to valuable 
> fisheries, parasite introductions and the endangerment and extinction 
> of native species.
>
> "Releasing non-native reef fish is like playing Russian roulette with 
> tropical marine ecosystems," Semmens says. Then, too, even if 
> introduced species do not have dramatic impacts, their presence is 
> unnatural and unwanted.
>
> "Divers visit the reefs of Florida to see the region's natural beauty 
> and diversity. It is a unique and magical experience to dive on these 
> reefs. Adding new species to the region is comparable to adding a few 
> finishing touches to one of da Vinci's masterpieces."
>
> Co-authors of the paper are Eric Buhle and Anne Salomon, both UW 
> doctoral students in biology, and Christy Pattengill-Semmens, science 
> coordinator for the Reef Environmental Education Foundation.
>
> Aquarium keepers need to be educated about the proper disposition of 
> animals in their care, according to Paul Holthus, executive director 
> and president of the Marine Aquarium Council, an international 
> non-profit organization based in Honolulu that focuses on the way 
> tropical fish are collected and handled before they are purchased.
>
> "While it is against the law to release non-native marine fish into 
> coastal waters, it's a problem that can't easily be policed," Semmens 
> says. The authors say that education programs for dealers and 
> aquarists could curtail exotic species introductions if implemented 
> properly. Such programs would need to highlight the problems of 
> introduced species and provide ways for aquarium owners to sell or 
> trade unwanted fish.
>
> ###
>
> - For more information: Semmens, 206-529-1240, 
> semmens at u.washington.edu <mailto:semmens at u.washington.edu>
> - "A Hotspot of Non-native Marine Fishes: Evidence for the Aquarium 
> Trade as an Invasion Pathway," Marine Ecology Progress Series, vol. 
> 266, Jan. 30, 2004
> - Reef Environmental Education Foundation's Exotic Species Sighting 
> Program, http://www.reef.org/exotic/
> - Holthus, 808-550-8217, paul.holthus at aquariumcouncil.org 
> <mailto:paul.holthus at aquariumcouncil.org>, Marine Aquarium Council, 
> see http://www.aquariumcouncil.org/


-- 
Christy Pattengill-Semmens, Ph.D.
Scientific Coordinator
Reef Environmental Education Foundation (REEF)
www.reef.org