NEWS

Bat houses help temper Zika threat in Brevard

Jim Waymer
FLORIDA TODAY

James R. Adam sees a simple, pesticide-free Zika prevention plan: bats.

"In today's fast-paced world of cellphones and self-importance, I thought that maybe I could reconstitute the bat house idea," said the Titusville resident.

James R. Adam shows a bat house he made. He says bats can help eat back threats from Zika and other mosquito-borne diseases.

He's fashioned his own bat house and wants to spread the word for others to use them. The city of Rockledge recently put bat houses on aluminum poles at Larry Schultz Park and five other parks. Bat houses have popped up countywide at parks, schools, even at NASA's Kennedy Space Center in recent years. But scientists and conservationists caution that bats are far from a cure-all for mosquito-bore illnesses, especially Zika. The types of mosquitoes that spread Zika are "day biters" and bats feed at night, so seldom do the two cross paths.

"The bats are probably not going to have a major impact unless that mosquito is out at dawn and dusk," said Shari Blissett-Clark, of Bat Belfrys, a nonprofit on Merritt Island that builds and installs bat boxes, including the recent ones in Rockledge.

Brevard prepared to fend off Zika virus

She's been getting more requests for bat houses, lately, because of Zika.

"I think it's a great thing, in one regard: Bats are really good about controlling all night flying insects," Blissett-Clark said.

She's installed about 300 bat boxes statewide with her non-profit organization, Bat Belfrys. The boxes run $100 each or $325 installed on a 16-foot pole.

Blissett-Clark also is on the board of the Florida Bat Conservancy, a nonprofit conservation group based in Clearwater.

A bat box was recently installed at McLarty Park in Rockledge to attract bats to help control mosquitoes

Bats have been struggling in Florida and elsewhere in North America, under the scourge of habitat loss, a new fatal fungal disease called white nose syndrome and other threats. There are 13 species of bats in Florida.

Blissett-Clark said the conservancy is working with the Florida Fish and Wildlife Conservation Commission and Lubee Bat Conservancy in Gainesville to develop a long-term study of bat guano, to see just how many mosquitoes and other types of insects bats eat. They'll collect fresh guano underneath bat houses, freeze it, and send out for analysis.

"We're going to take a more comprehensive look at  guano so we can determined exactly what insects bats are eating and what ratios," Blissett-Clark said.

Heavy rains such as the Space Coast got this week tend to swamp out the mosquito species that transmits West Nile and St. Louis encephalitis viruses, entomologists say. Excess water flushes immature mosquitoes from hatching sites and dilutes the nutrients they need to survive.

At least 6 Zika cases in Brevard; none contracted locally

But the mosquito species that transmit Zika, dengue and chikungunya viruses thrive under extreme wet conditions.

They can bite an infected person and spread the viruses to another person.

So far, local transmissions of Zika virus has been mostly in two small areas in Miami-Dade County, including less than a one-square mile area just north of downtown.

As of Thursday, the Florida Department of Health had reported 12 travel-related Zika cases in Brevard and a 576 travel-related cases statewide, and 49 locally acquired cases. Statewide, 80 cases involve pregnant women.

Only about 1 in 5 people infected with Zika virus have symptoms. Most people to get sick experience a fever and mild illness. But in rare cases, severe disease can require hospitalization. Zika is mostly a concern for pregnant women because it can devastate fetal brain development, resulting in newborns with much smaller than normal heads and brains.

New bat houses in Rockledge await their guests

According to the state department of health, symptoms may include low-grade fever, rash, joint pain, conjunctivitis (reddening of eye), body aches, headache, eye pain and vomiting. Doctors can treat the symptoms but here is no specific treatment against the virus. Illness typically resolves within a week.

Fish, small crustaceans, damselfly nymphs and frogs also will eat mosquito larvae. Frogs, birds, bats, dragonflies and damselfly adults eat adult mosquitoes.

But most times, nature is not enough.

Health officials warn residents to empty standing water from discarded tires, shells, pots and other containers where the mosquitoes that spread the disease breed.

An Aedes Aegypti mosquito is photographed on human skin in a lab of the International Training and Medical Research Training Center (CIDEIM) on January 25, 2016, in Cali, Colombia.

As for the bats, Adam still sees a strong role for some of nature's best insect eaters.

"Farmers have been using them for centuries. Are we so used to technology that our first response is to throw pesticides, genetic research and money at a problem," Adam said.

"Bats may not like the city lights and to keep the population regulated, I would suggest using bat boxes in the unincorporated and problem areas around a city," Adam added. "That way, you would have contained city mosquitoes, rural mosquitoes and wild mosquitoes."

Bats live about 17 to 25 years. They'll occupy most bat boxes within a year of installation, typically dozens per box. .

Contact Waymer at 321-242-3663 or jwaymer@floridatoday.com Follow him on Twitter@JWayEnviro and at facebook.com/jim.waymer

Placing a bat house

Bat experts give these tips for placing a bat house:

  •  Install the house at least 12-15 feet above the ground; the higher the better;
  • Put it high on a house or pole, not in a tree;
  • An open space is better, so bats don't run into trees or other obstacles during their approach;
  • Have the house face south or southeast for maximum solar warming;
  • Putting the house near fresh water is a plus, but water isn't usually an issue in Florida;
  • Make sure the house has a "landing pad" or an area where the bats can alight and crawl inside;
  • A minimum of three chambers is ideal, with each chamber about 3/4-inch wide.
  •  Ensure the house will withstand high winds without falling.
  •  Consider placing a net beneath the house to catch baby bats if they fall.

Source: FLORIDA TODAY archives