If your butterfly net has been coming up empty lately, you're not alone. According to a report from the European Environment Agency, the number of butterflies in the open countryside has halved over the last two decades. The Danish nature agency, Naturstyrelsen, confirmed that the number of butterflies has fallen dramatically domestically as well, largely due to a reduction in breeding areas.
“[The European decrease] doesn’t surprise us because the amount of natural area where butterflies can spawn is greatly diminished,” Erling Krabbe, a biologist at Naturstyrelsen, told DR News.
A lack of butterflies has more than just aesthetic implications due to the important role the delicate insects play in pollination. As a result, Naturstyrelsen has launched an effort to restore some of the country’s natural areas.
While the butterflies may have flown the coop, the recent heat wave has increased the numbers of their ugly and unpleasant distant cousin, the swamp mosquito.
While other types of mosquitoes are adversely affected by the warm dry weather and have seen their populations decrease, the swamp mosquito is currently flourishing in and around Denmark's lakes and ponds. The cool June held the nasty little buggers at bay for a while, but the current heat wave has their numbers increasing by leaps and bounds.
Researchers at the Technical University of Denmark's (DTU) veterinary institute keep a close eye on mosquito populations in order to prevent the diseases that the bloodsuckers can spread among livestock and humans.
In 2008, mosquitoes, gnats and midges spread bluetongue disease among cattle herds and last year the Schmallenberg virus, which can result in deformed calves and lambs, was discovered in several locations throughout Denmark.
"We have not seen so many mosquito-borne diseases in Denmark since the malaria epidemic in the mid-1800s,” René Bødker, an epidemiologist from DTU's veterinary institute, said in a press release. “In recent summers, Germany’s blackbirds have been hit by an outbreak of the African Usutu virus, which in rare cases may also infect humans, and over 2,000 people in Madeira in Portugal have been infected with dengue fever."
Bødker’s best advice on how to deal with mosquitoes was to swat them as soon as you see them.
The decrease in butterflies and most mosquitoes comes at a time when bee populations are also decreasing dramatically.