Mosquitoes, Fish, Pools and Foreclosure

What do these four have in common? More than you might think.

ByABC News
July 11, 2008, 5:25 PM

July 14, 2008 — -- We're advised to eat things that are green and buy cars that are green. Green is the buzzword of today's world.

But nobody wants a green swimming pool.

As the foreclosure crisis deepens by the day, an unsightly and potentially deadly consequence of homes without owners are neglected swimming pools. An abandoned pool can become contaminated with algae within two weeks. Shortly after that, the mosquitoes follow in the millions.

It's a mess far too pervasive to stave off without daily work with a skimmer and a dash of chlorine.

It's times like these that neighbors and homeowner associations turn to a 2-inch fish with a big appetite. Gambusia affinis, more commonly known as mosquito fish, have been used in this way since the 1920s. They are released into green pools in small batches of about 100, and they breed and eat hundreds of mosquito larvae a day.

"These fish are an awesome ally," said Jon Miller a 22-year veteran technician at the Orange County Vector Control District. "I've had to treat over 200 pools in the last three months and with these [fish] I don't need to come back."

The government agency -- which is charged with stopping the transmission of diseases spread by insects and animals -- abandoned its policy of using only pesticides when it became clear that foreclosed homes were sitting unoccupied for months rather than weeks. They still use chemical agents but only in small amounts, and they specifically target mosquitoes, leaving other aquatic life unaffected.

Mosquito fish have a life expectancy of more than two years and can survive with very little oxygen, making them the perfect long-term treatment for mosquitoes breeding in backyards.

Specialists say the only real problem with using mosquito fish in unnatural waterways like swimming pools is the public's lack of knowledge regarding them.

"It breaks my heart to come back to a pool we've just treated and see all the fish dead because somebody has used bleach thinking that they're helping," said Mike Hearst, director of communications at Orange County Vector Control