Air Date: Week of June 21, 1996

With mosquitoes out in droves this summer, Steve Curwood talks with John Rusmisel, manager of the Alameda County Mosquito Abatement District in Hayward, California for advice on some natural ways to keep the biting insects from getting to you.

Transcript

CURWOOD: It's Living on Earth. I'm Steve Curwood. After an unusually wet winter, mosquitoes are back with a scratchy vengeance in much of the country this year. Pest control officials usually fight the pesky insects with synthetic chemicals. While individuals are turning more and more to those ultraviolet bug zappers. But neither solution is very good for the environment. Pesticides harm people and other creatures, and it turns out that patio bug zappers kill lots of beneficial insects but very few mosquitoes. But there are more benign alternatives for mosquito control. John Rusmisel is in charge of mosquito abatement in California's Alameda County. Mosquitoes breed in standing water, so Mr. Rusmisel says you should start by draining every container that holds water around your house.

RUSMISEL: We're talking about holding water, we're talking about perhaps a cup of water or less. In our area we have a lot of people who keep cuttings for plants in buckets and they get rainwater in them, or just the water for keeping the plants going cause a lot of mosquito problems. We also have things like boats that don't have the drain plugs taken out of them, that will hold rainwater in them. Water under a house, if you have a basement with a sump pump and the pump's not taken care of, that'll cause a mosquito problem. Tires, tires can be a very big problem throughout the country.

CURWOOD: Now you're the district manager of the Alameda County Mosquito Abatement District, and I understand that the Alameda County program is fighting mosquitoes with fish.

RUSMISEL: We're using a fish called a mosquito fish, gambusia effinis, and we put the mosquito fish into containers that are sources of mosquitoes, everything from residential fish ponds to unused swimming pools to fountains. A lot of people are using half whiskey or wine barrels now as water gardens. Just about anything that can hold the fish where they'll survive.

CURWOOD: And these fish eat the mosquito larvae, is that it?

RUSMISEL: They're very good at eating mosquito larvae. They can eat literally hundreds of them a day.

CURWOOD: But what happens if they run out of mosquitoes to eat?

RUSMISEL: They're very opportunistic feeders. They will feed on any kind of zooplankton or invertebrate in the water. That's why we don't put them into a lot of streams and rivers nowadays. But as far as a person's residential pond, that's not a real problem.

CURWOOD: Hmm. How can people get a hold of mosquito fish?

RUSMISEL: Well, if there's a mosquito abatement district or a public health department that's doing mosquito control, chances are that they can provide mosquito fish for them.

CURWOOD: Now, in addition to mosquito fish, your department also uses bacterial larvacide to control mosquitoes. How do those work?

RUSMISEL: Well, we switched to using bacillus therengensis israelensis, or BTI, which is very common throughout the country. It's a stomach poison. The mosquito larvae, if they feed on enough of it, will die.

CURWOOD: But it doesn't hurt the environment otherwise?

RUSMISEL: No, it's a very specific pesticide, which is why it's a good product for IPM, or integrated pest management. It really affects only mosquitoes and black flies.

CURWOOD: What other methods do you use that don't use synthetic chemicals?

RUSMISEL: Well, this could be considered a slightly synthetic chemical. We use an insect growth regulator called Altacid, or Methaprene. Methaprene is the chemical name. It prevents them from coming out of their pupal case. It doesn't cause an outright immediate death of mosquito larvae, and so other animals and insects can feed on these larvae so it doesn't take them out of the food chain. And it's not something that biomagnifies in other animals.

CURWOOD: John Rusmisel runs the Alameda County Mosquito Abatement District in Hayward, California.