Insects that’ll be bugging us this soggy summer
By Mike Danahey firstname.lastname@example.org July 9, 2013 1:35PM
Japanese beetle adults & damage on rose foliage
With this spring and early summer’s soggy weather, what’s the buzz on the bugs that typically bug us this time of year during our picnic outings, backyard barbecuing, hiking and even sitting on the sofa indoors to beat the heat?
According to University of Illinois Extension entomologist Phil Nixon, with the conditions we’ve been having here in Northern Illinois, some pests will be out in force, while other insect populations will suffer.
Per those walks in wooded areas, Nixon said, “We’ve seen more ticks in DuPage and surrounding counties in the past few years. Deer ticks were unknown in those areas for several years, but are now being found, although they are rather uncommon. Lone Star ticks have become common in those areas, and American dog ticks have become more common, particularly this year.”
While Lyme disease carried by the deer tick has been a health concern, in an article Nixon wrote for the extension’s May 20 Home, Yard & Garden Newsletter, he wrote that the dog ticks “transmit Rocky Mountain spotted fever, a virus found here but most common in North Carolina and nearby areas. In Illinois, they also carry ehrlichiosis, producing symptoms similar to Lyme disease.”
“Ticks are numerous in areas of tall grass, where humidity is high and hosts common. Mowing greatly reduces tick numbers,” the article states.
In terms of mosquitoes, it’s a mixed proposition for them and their animal and human victims.
With flooding and large amounts of rain comes an increase in the inland floodwater mosquito population, Nixon said. With recent precipitation patterns, Nixon said their presence might next be felt in this area after the Fourth of July weekend, meaning most holiday parties were probably mosquito-free.
Nixon noted that this type of mosquito, while noisy and a painful biter, has a bite that doesn’t carry disease.
According to Nixon, the West Nile Virus-carrying species of mosquitoes are quiet biters that thrive under hot, dry conditions like we had last summer. This year, with rains washing out the stagnant pools these types find to breed, their numbers should be down.
According to a press release from the Illinois Department of Public Health, last year, 55 counties in Illinois reported a West Nile virus-positive mosquito batch, bird and/or human case. For the 2012 season, IDPH reported the second-highest number of West Nile virus human cases in state history with 290 sick residents and 12 deaths. This was second only to the 2002 outbreak in Illinois, in which 884 residents contracted West Nile and 67 died.
As of July 5, no cases in humans had been reported this year, but the virus had shown up in several mosquito batches tested for the strain across the state, including ones found in Naperville, Hillside, Harvard and Skokie.
“There will still be enough to transmit disease, but probably not as much as last year,” Nixon said.
Wasps and butterflies
In recent weeks people have reported seeing wasps swarming about and nesting in some unusual places, including one Elgin resident who found the insects had built a mobile home inside the rear-view mirror of the family’s minivan.
Nixon said that for about a decade, the number of European paper wasps in the Chicago area has been increasing, and this year people are noticing more and more of them and their upside-down-umbrella-shaped nests.
“Those nests can turn up in any sort of crevice or cavity — be it under used backyard grills, in clothesline cross arms, under eaves, and in doorways, attics and wall boards,” Nixon said.
Included in the wasps’ diet are caterpillars, Nixon said, which means that moths and butterflies become increasingly rare where these wasps take up residence. With this year’s rainy spring, the numbers of moths and butterflies coming from caterpillars also is being lessened by a fungal disease they can pick up in moist conditions.
The European paper wasps are not to be confused with the smaller yellow jackets, which have been a frequent picnic pest in these parts, particularly in late summer and early fall.
The yellow jackets are adaptable and eat any sort of meat, including what people put out in garbage cans and Dumpsters. And if a garbage lid is left open, the yellow jackets can chew through plastic bags.
Nixon guessed that yellow jacket numbers may be down this year in rural areas, in part because they, too, feast on caterpillars.
“However, in urban and suburban areas, they are likely to be numerous due to people inadvertently feeding them with their trash,” Nixon said.
Some good news
In good news for your rose bushes, birch trees and other plant life, a residual effect of last summer’s hot, dry weather is that the number of Japanese beetles should be down because of the lack of water last year impacting the ability of larvae to develop.
Fireflies tend to do better with a wet spring, so you might be seeing more of them this year than in recent summers, Nixon surmises. But according to Carl Von Ende, a professor of biological sciences at Northern Illinois University, the number of fireflies has dwindled in recent years with any number of reasons posited for this, including development and light pollution.
Nixon also noted that due to the moistness and ensuing mildew, the numbers of tiny springtails — the most numerous insects on earth — are up this year, too, as will be the number of earwigs.
Aside from being pests, though, except for the mosquito and tick species that spread disease and those allergic to insect stings, few if any of the insects to be found in abundance this summer should pose a threat to human health, Nixon said.