Mosquito management targeted at DINA meeting

They’re small. They’re menacing. And if you live on Daniel Island - you have likely felt their stings. It’s mosquito season all across the Lowcountry - and efforts to keep the insects’ biting population at bay are in full swing. At the June 6 meeting of the Daniel Island Neighborhood Association, Berkeley County’s Mosquito Abatement Manager Jeff Carey briefed attendees on what his department is doing to control the pesky predators.

According to Carey, at 704,000 acres - Berkeley County is the third largest county in the state and likely the most “environmentally diverse.” That means there are a high number of breeding sites, including the Santee River flood plains, wetlands, freshwater swamps, Carolina bays, and salt marshes, he explained. Those areas, in addition to manmade water collectors like bird baths, used tires, and children’s toys, make the Lowcountry a haven for mosquitos. In addition to being a general nuisance, the bugs can also carry a number of diseases, noted Carey, such as Malaria, Eastern Equine Encephalitis, West Nile Virus, Yellow Fever, and the Zika virus. The mosquito-borne heart worm virus can also pose a threat to pets.

“We’ve got 62 different species of mosquitos here,” he said, to the DINA crowd. “…It would just not be livable on Daniel Island without mosquito control.”

Carey and his team run an integrated pest management plan that includes surveillance, juvenile control, adult control and public outreach. They break the county down into 24 zones, he continued, and in each zone they conduct regular landing rate counts and do routine water checks to inspect for breeding. Carey personally inspects Daniel Island four times per week.

“Y’all may have seen me wandering around in your salt marshes counting mosquitos,” said Carey. “We’ve inspected 1,000 bodies of water for breeding. We go and take larvae dips and if we find larvae present, we treat the water.”

Here are some of the questions posed by DINA audience members, along with Carey’s responses:

Q: How do you make sure your spraying does not kill our pollinators?

Jeff Carey (JC): Our truck based spraying is done at night. The pollinators are not out at night…they come back to the hive…We contact every bee keeper in the area where we’re spraying by aircraft by phone at least 24 hours ahead of time. If we can’t reach them by phone we go to their house. That way we can tell them ‘we’re going to be spraying tomorrow morning, please tonight when your bees come back to the hives, close the hives up, and if you want to take the extra precaution of putting a wet sheet over the top, that protects the hive.’

Last year and the year before...we sprayed 450,000 acres by air and didn’t lose any hives, and that’s with 125 bee keepers, so we’ve been real good about working with our bee keepers.

Q: When you do the aerial applications - does it kill the mosquitos immediately? And if I’m out walking is it dangerous (to my health)?

JC:…It kills some (mosquitos) immediately, but generally within 48 hours we see the full effect of the control. We spray what’s known as ultra low volume. We’re taking the pesticide and we’re breaking it up into micron-sized droplets, by aircraft about 30 microns. And that’s 30 microns in an air column 15 feet high at one ounce per acre…So, if most of you are on quarter acre lots, if one ounce is broken up into four different properties in an air column 20 feet high in micron sized droplets, you’re not going to run a risk even if you’re outside...Having said that, we encourage you to be inside. We will not spray during the weekdays when school is in session. We always put it off to the weekend. We generally spray Daniel Island first because you’re an active community (typically before 7 a.m.).

Q: I’ve seen a couple of companies offering mosquito abatement (systems for residential and commercial properties)...is this a valuable commodity? Does it help? Does it enhance what you’re already doing?

JC: I think it probably does enhance. There are a couple of approaches to mosquito control. There is the ultra low volume technique. We try to spray micron-sized droplets into the air when the insects are flying. The mosquitos fly into the droplets and it kills them. These companies that are coming by, their process is putting out a residual spray. They’re spraying a product on your plants, on your vegetation…it’s made to last for about two weeks. Within two days our product is out of the environment. It’s no longer viable in the environment. And that’s what we’re looking for. We want our products to work and be gone.

Q: Is there a schedule in public somewhere, so we know when you’re spraying?

JC: Yes. We do not spray on a set schedule. We use our surveillance data. We want to be data-dependent to determine where we are going to spray. Our inspectors are out every day and when they bring their numbers back that’s where we send our trucks. We post a schedule online on the Berkeley County website (www.berkeleycopunty.sc.gov). Click on “events” and then “spray schedule” and it will show where we are going to spray every day. We update that by 2 p.m. every day. When we spray by aircraft, we publish that through every format we have - newspapers, radio, and we contact your DI group (Daniel Island Property Owners Association).

Q: What do you spray?

JC: We actually use three compounds. When we spray by ground we use two products - we use mosquito mist, an organophosphate, and we also use aqua-reslin, which is a synthetic pyrethroid…a synthetic compound of pyrethrin (a derivative of the chrysanthemum plant). When we spray by aircraft, we use an organophosphate called TRUMPET, which is Naled.

Q: Are you spraying the southern tip of Daniel Island, the port land, or is Charleston County still doing that?

JC: We both do it. Charleston County is contracted by the State Ports Authority and the Army Corps of Engineers to provide mosquito control on the dredge sites on the tip of the island. Having said that we recognize that it is a problem for our citizens, so when we spray we include (that area) in our spray as well. We will always spray that when we spray Daniel Island.

For answers to other frequently-asked questions, including information on mosquito spray schedules and zones, visit the Berkeley County Mosquito Abatement website at https://www.berkeleycountysc.gov/drupal/mosquito.