Conservation and Pet Fish

Fill an Aquarium Without Emptying the Sea

  • Michael Lipske
  • Dec 01, 2007
By following a few simple guidelines, fans of tropical fish can maintain their collections while protecting wild populations and coral reefs from further damage

YOU’D EXPECT Drew Weiner to be flatly against the whole notion of keeping tropical fish as pets. After all, Weiner is a coral conservation crusader, head of an organization called Reef Protection International.

He has scuba dived on reefs around the world and seen firsthand the damage the aquarium trade can inflict on ocean ecosystems. One example: It’s common for collectors in Indonesia and the Philippines, sources of the majority of saltwater aquarium fish, to squirt cyanide into coral crevices. The cyanide stuns fish, making them easier to collect. But the deadly poison also kills nearby animals, including corals, that aren’t the target of collectors. Moreover, a large percentage of cyanide-captured fish die soon after being plucked from reefs.

“There’s a lot of waste,” Weiner says of the international aquarium trade. “You’ve got 20 to 25 million fish being collected every year and some studies show that half of those die in the process.” (Unlike freshwater aquarium fish, most of which are bred in captivity, the animals that populate saltwater or marine aquariums are largely collected from the wild.)

But Weiner also knows that the only way many people will ever see a brightly colored clown fish or a specimen of living coral is through the thick glass of a home aquarium. “It’s a source of inspiration,” he says. “Coral reefs are in crisis and we need to get more people interested in making sure that they survive in the future.”

Beset by pollution, global warming and other threats, the world’s coral reefs are in such trouble that any effects from the tropical fish trade may seem like a drop in the bucket. But coral conservationists say the aquarium trade compounds the stress reefs already endure.

As many as 2 million people worldwide keep marine aquariums, including roughly 800,000 American households. If you’re considering taking up the hobby, there are ways to reduce negative impacts on wild reef ecosystems while still having a beautiful aquarium.

First, says Weiner, “do a lot of research to make sure that you can take care of a saltwater aquarium,” and be sure that your tank setup provides proper living conditions.

Second, seek captive-bred species whenever possible. A handful of companies are farming marine fish for the aquarium industry, augmented by small-scale home breeders who supply captive-reared fish to local pet stores.

Reef Protection International, which was established to promote consumer behavior that helps conserve coral reefs, offers a free Reef Fish Guide to help you identify tropical aquarium fish that are available as captive-bred specimens or whose collection from the wild threatens neither the species nor coral reefs. The guide also names species you shouldn’t buy because they tend to fare poorly in captivity, because their populations are declining or because methods used to collect them harm reefs. Modeled after pocket-sized guides to safe and sustainable supermarket fish, the Reef Fish Guide can be downloaded from Reef Protection International’s website,

Fish aren’t the only aquarium animals produced in captivity. Avid aquarists have perfected the art of propagating coral from fragments. “Frags” to those in the know, these are corals whose distant ancestors were collected from the ocean. Once established in aquariums, the coral colonies are cut into fragments used to grow new colonies. “There are corals that I am sure are on 10-plus generations,” says Michael Gerdes, cofounder of the Washington, D.C. Area Marine Aquarist Society.

Aquarists trade tips on the art and science of aquarium keeping, which is why both Gerdes and Weiner say that anyone hoping to keep a marine tank should connect with a local aquarium society. To find one near you, try the National Club List at the website of Marine Aquarium Societies of North America,

For Gerdes, who started keeping aquariums in childhood, the hobby lets him “observe an ecosystem in captivity.” Nearly 50 species of captive-propagated coral thrive in his various aquariums.

Gerdes’s advice to novice and experienced aquarists alike is to be aware of the impact of their hobby on coral reef communities. As Gerdes says, “Whatever efforts can be done to encourage not removing things from the ocean is a step in the right direction.”

Washington, D.C., journalist Michael Lipske wrote about mercury levels in fish in the August/September issue.

Vital Reefs

Coral reefs cover only about 1 percent of the Earth’s surface, yet they are home to more than 25 percent of all marine life.

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The Cost of Losing Coral Reefs

In the near future, global warming, pollution and overfishing could mean a dramatic loss of tourism dollars in regions that are home to coral reefs—including the Florida Keys. At a recent meeting of the multinational Coral Reef Task Force, researchers warned that a growing number of studies indicate that not only corals and the extraordinary wealth of animal life that depends on them are at risk: Human livelihoods and communities will also suffer if reefs from Florida to Australia to the Philippines continue to degrade. Ecotourism accounts for nearly one-fifth of the tourism dollars spent worldwide, according to a 2004 study on the health of the world’s coral reefs commissioned by the Australian government. In Florida alone, tourists visiting the coral reefs contribute more than $1 billion each year to the local economy.—Hannah Schardt 

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