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Where Have All the Insects Gone? (sciencemag.org)
Entomologists have been assessing diversity and abundance across western Germany and have found that between 1989 and 2013 the biomass of invertebrates caught had fallen by nearly 80 percent. From an article on Science magazine: Scientists have tracked alarming declines in domesticated honey bees, monarch butterflies, and lightning bugs. But few have paid attention to the moths, hover flies, beetles, and countless other insects that buzz and flitter through the warm months. "We have a pretty good track record of ignoring most noncharismatic species," which most insects are, says Joe Nocera, an ecologist at the University of New Brunswick in Canada. [...] A new set of long-term data is coming to light, this time from a dedicated group of mostly amateur entomologists who have tracked insect abundance at more than 100 nature reserves in western Europe since the 1980s. Over that time the group, the Krefeld Entomological Society, has seen the yearly insect catches fluctuate, as expected. But in 2013 they spotted something alarming. When they returned to one of their earliest trapping sites from 1989, the total mass of their catch had fallen by nearly 80%. Perhaps it was a particularly bad year, they thought, so they set up the traps again in 2014. The numbers were just as low. Through more direct comparisons, the group -- which had preserved thousands of samples over 3 decades -- found dramatic declines across more than a dozen other sites. Such losses reverberate up the food chain. "If you're an insect-eating bird living in that area, four-fifths of your food is gone in the last quarter-century, which is staggering," says Dave Goulson, an ecologist at the University of Sussex in the United Kingdom, who is working with the Krefeld group to analyze and publish some of the data. "One almost hopes that it's not representative -- that it's some strange artifact."
"Scientists have tracked alarming declines in domesticated honey bees, monarch butterflies, and lightning bugs. But few have paid attention to the moths, hover flies, beetles, and countless other insects"
In other news,:birds eating those missing insects are declining rapidly as well.
http://onlinelibrary.wiley.com...
When I was a kid you could see tens of thousands fireflies at night in the country around here. In the early eighties the pine beetle started spreading through the tree farms around here. They started aerial spraying of pesticides to kill them and in just a few years you stopped seeing them at all. In the last decade or so they have reappeared, in very low numbers.
I spent many years in the mosquito control field. Trust me, they're coming. You just need rain followed by a warm spell.
Animal and plant species vary by how well they deal with disruptions. Species which deal well with disruptions and which have a high reproduction rate is a weedy species and thrives when we screw things up. Specie that reproduce slowly and are dependent upon certain specific things in the environment are the ones that disappear.
Most mosquito species are weedy. The larvae live on rotting organic matter in water and the adults live on nectar from a variety of sources. In some species a gravid female can lay two hundred eggs after a blood meal, and do that a half dozen times a year in some places. This means they have immense potential for exponential population growth, provided they have sources of water, temperatures warm enough to breed, and someone to get blood meals from.
Ecological disruption doesn't always look like death; in fact quite the opposite it can sometimes look like a profusion of life, as in a polluted lake choked with algae. But you lose most of the food chain: the fish and invertebrates they feed on. Or in cases like this it can be subtle; you might not see it until you look and wonder why a certain bird species is gone. Then you look and find out that the things it lives on are gone too.
But don't worry about mosquitoes. Unless your climate gets drier and cooler, you can count on them coming back.
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