Tiny Fish Curb San Joaquin County's Mosquito Population

This is National Mosquito Awareness Week, and of special concern is the threat of West Nile Virus. One way to prevent mosquitoes is putting fish in the pond.

Aaron Devencenzi with San Joaquin County Mosquito Control is giving away mosquito fish. He meets up with Rick Wentworth who has a little pond.

Wentworth is taking a dozen of the tiny inch and a half fish to his Manteca home.

"Well we noticed the larvae in the pool so rather than using some chemicals I just thought I'd do the fish and see if that works," says Wentworth.

Homeowners can use the fish in neglected swimming pools, decorative ponds and animal troughs, and Devencenzi says they do make a difference.

"The mosquito fish can eat anywhere from 80-100 mosquito larvae per fish per day. Real good control for mosquitoes, pretty much reduce all the mosquitoes that come out of that area."

And as the temperatures rise so does the mosquito population and the threat of West Nile Virus. 

"[The fish] should live two and a half to three years if the water doesn't freeze over," says Devencenzi.

Devencenzi says West Nile Virus showed up this week in San Joaquin County in mosquito samples and from a dead bird.

"Mosquito fish, we encourage the use of those in animal water troughs, in swimming pools that are neglected, you don't swim in, they're green, they're dirty. We use them in ornamental ponds where there is no other fish, and water features like half barrels that have lily pads and that stuff in them."