Are the outdoors quieter? A host of threats are impacting Connecticut’s insect population
It’s summer in Connecticut, when many residents’ thoughts turn to backyard barbecues, the beach and the bugs that reliably accompany them.
But some residents have noticed their backyards have been oddly quiet since the weather warmed — less buzzing, fewer mosquitoes and fewer bees. Some social media users have commented that they’re not seeing as many insects as in years past, which has fueled speculation that the population is decreasing in the state.
The world has lost more than one-quarter of its land-dwelling insects in the past 30 years, according to the journal Science. Pollinators such as bees and butterflies, insects that are crucial to the world’s food supply, are disappearing at an estimated rate of just under 1% per year with lots of variation from place to place.
“That number may not seem like a lot but that’s 30% over a 30-year span,” said Dr. David Wagner, entomologist and professor at the University of Connecticut. “It’s obvious to most people just looking out their back window that there’s less wildlife today than there was just 20 years ago.”
Climate Change driving loss of some species, proliferation of others
A dramatic increase in Earth’s carbon dioxide levels and temperatures, reported by the UN’s Intergovernmental Panel on Climate Change in 2021, is shaping Connecticut’s insect population as summer temperatures increase and the state experiences milder winters on average. The state has already lost some species that are adapted to colder climates. Rather than going extinct, they still maintain colonies in the Berkshires and northward where it is cooler.
“We’ve been adding species from the south at a pretty good clip presently since the 1980s that are suited for our warmer climate,” Wagner said. “But the state is certainly also losing species due to climate change. Many of them are moving further north as our state continues to heat up.”
Some of those lost native species include the arctic skipper, a small woodland butterfly, and the Atlantis fritillary. The fritillary, a butterfly known for its distinct black markings and black wing margins, is now listed as endangered in the state.
“The butterfly population has been the most affected,” said Wagner. “We’ve seen great declines in populations over the last few decades. At this point we’re losing about half of a butterfly species a year. While again this may seem marginal, it is a noticeable decline over several years.”
One of the relative newcomers to Connecticut is the lone star tick, which is native to the southeastern United States. Named for the silvery-white star-shaped spot on its back, the lone star tick is a vector for ehrlichiosis and a number of other diseases. Chiggers are another unwelcome new pest.
“We’re seeing as a result of climate change new ticks and the introduction of chiggers and all the diseases these creatures carry,” said Wagner. “The lone star tick is particularly of concern because of the diseases that species carries than can make humans sick. As winters become milder, tick breeding season is coming earlier than before, which means an explosion in the tick population. That’s a major concern.”
Honeybees face a perfect storm of threats
Honeybees, which play a critical role in the food production system, are also declining in Connecticut, Mark Creighton, state apiary inspector, said.
“Honeybees play a vital role in providing food both nationally and here in Connecticut,” Creighton said. “But the honeybee faces a lot of stressors today. For starters, they face loss of habitat, viruses and parasites which are contributing to declining numbers.”
The varroa mite is just one of the many threats to Connecticut’s bees. The parasite attaches itself to honeybees much like ticks attach themselves to animals or humans and can be a vector of more than 18 bee viruses.
“The varroa mite feeds on the fat bodies of the bee, which contain the protein,” said Creighton. “That is robbing the bees of the royal jelly they create to feed the developing bees and the queen bee later on in the year. By depleting this protein source, they are draining the colony of its life.”
Bee viruses are another threat. Many of these viruses, including deformed wing virus, sacbrood virus and paralysis virus, are spread from the varroa mite while others can spread between colonies.
“The deformed wing virus is exactly how it sounds,” said Creighton. “Picture your dress shirt coming out of the wash and putting it in the dryer and then taking it out and it’s all crinkled. That’s what happens to the bees’ wings. They get all crinkled. So when it’s finally their turn to stretch their wings and fly from the colony, they cannot. The best they can do is hop on the ground and become susceptible to predation.”
Steps to mitigate the damage
Such stressors have created a perfect storm that is threatening honeybee colonies around the country especially as human overpopulation encroaches on natural habitat. But Creighton says there are things people can do to ensure success for pollinators like honeybees.
“Protecting our pollinators is something everyone can do,” Creighton said. “Plant pollinator habitats can be grown just about anywhere even in urban environments. You can take a straw bale and condition it so that you plant just about anything in it even in the middle of an asphalt parking lot. Everyone can grow things and help create pollinator habitats no matter where you live.”
Some of the most popular pollinator plants in Connecticut include Swamp Milkweed, New England Asters, New Jersey Tea, Button Bush, Rough Goldenrod, Golden Alexanders and fruits like blueberry and raspberry.
Wagner said that while climate change continues to shape the insect population in the state, its impact too can be mitigated with effort.
“It may not be a welcome message, but climate change is a reality and it’s here in our state,” Wagner said. “The state should be actively trying to mitigate the threat of climate change through land preservation. This includes planning green space and corridors where animals can move.
“We don’t want to design a state where urbanization is so intense that there are no corridors for animals to move to the north to seek refuge. We should try to help Mother Nature as much as possible to weather the impacts of climate change.”
Stephen Underwood can be reached at sunderwood@courant.com.
