Floodwaters from Isaac may have washed away large numbers of West-Nile carrying mosquitoes, but the drenching rains also likely awakened sleeper cells of the insect pests that have lain dormant for years, officials said.
The number of mosquitoes caught in traps in Livingston Parish — which saw some of the worst flooding in the aftermath of Hurricane Isaac — dropped by nearly half after the storm, said Jeanine Tessmer, Director of the Livingston Parish Mosquito Abatement said.
“Many of them got flushed away with the rain,” Tessmer said. “The rain was a good thing from that point of view.”
However, the high rainfall amounts provided ample breeding ground for mosquitoes, and floods made it difficult for trucks to get into the southern part of the parish and spray for mosquitoes, she said.
In addition, some eggs that may have been laid in mud as long as 10 years ago could have been re-activated by Isaac’s waters, and could cause the numbers of mosquitoes to spike in the coming days, she said.
“By the end of next week, it will get worse,” she said.
East Baton Rouge Parish Mosquito Abatement Director Matt Yates said the number of mosquitoes in Baton Rouge was about the same as before the storm.
“Most of them are coming out of the wooded areas,” he said.
Yates called those “pest mosquitoes,” and said they are far less likely to carry the West Nile virus.
Yates agreed the number of mosquitoes could spike next week.
Agents were using trucks and an airplane to spray for mosquitoes, said Kenny Ricard, an inspector with the EBR Mosquito Abatement.
East Baton Rouge Parish has about 45 species of mosquitoes, Yates said.
One of the more common mosquitoes in East Baton Rouge Parish is the albopictus , or “albo” for short, Ricard said.
They tend to lay eggs in the things people have in their yards that collect water, he said. Turning over items such as toys and flower pots so that they won’t hold water can cut down on the mosquito population, he said.
“You will see more of them at dawn and at night, but they will come out during the day time,” he said.
The mosquito that most commonly carries the West Nile virus, the species quinquefasciatus , or “quink” mosquito is more common in septic ditches and sewer drains, he said.
To help keep mosquito numbers low, Yates advised residents to:
- Empty containers around the house that collect water, including birdbaths and pet water dishes.
- Drain or fill areas in the yard that collect standing water.
- Keep grass cut to remove resting areas for mosquitoes.
- Keep gutters clear of debris.
- Make sure swimming pools have enough chlorine — even if the pool is not being used.
