The North American Butterfly Association reports that the numbers of many species of butterflies seem to be about half of what they were last year through much of the US. The cause is uncertain, but this year’s cold, wet weather in the Eastern US is a likely suspect.
Today’s Wild Animal Facts
Butterfly numbers are down by about 50 percent this year, reports the Philadelphia Inquirer in a story about the North American Butterfly Association and its annual butterfly counts at 500 sites across the country.
Spokespersons for NABA told the Inquirer that cold, wet weather can delay the growth of larval butterflies as well as make them vulnerable to dampness-loving funguses. In addition, heavy rains can knock caterpillars off the flowering plants on which butterflies lay their eggs.
The good news is that if weather is indeed the culprit, butterfly populations will most likely recover in a year or two. Permanent harm to butterflies is almost always related to human activity, including the spraying of insecticides, quite possibly including Bacillus thurigensis, a supposedly “green” choice for killing gypsy moths.
So, if you want to help butterflies, use insect sprays very sparingly—or better yet, not at all.
The Inquirer article also says:
“Besides spraying, the butterfly association’s Glassberg has concerns about farms that raise and sell butterflies to schools and for celebrations like weddings.
“‘These well-meaning but unsuspecting folks wrongly think they’re increasing the number of butterflies out there and doing something good for the environment,” said Glassberg, who warned that farmed butterflies, raised in close quarters and “intentionally dumped into the environment” after use, spread disease to natural butterfly populations and decrease their genetic fitness through breeding.'”
One way you actually can help butterflies is to plant things they like, such as purple coneflower, butterfly bush, phlox and even joe-pye weed. And, if you’ve got milkweed growing around your house, leave it standing: The monarch butterflies depend on it. (Visit the NABA website for more suggestions.)
A single homeowner or gardener who plants the right sorts of flowers and is tolerant of a few species of weeds can increase the numbers of butterflies in their area.
Desert Tortoise Considered For ESA Listing
In other top 10 endangered species news, the feds are considering the Sonoran desert tortoise for listing under the Endangered Species Act. The tortoise, which lives in southern Arizona and northern Mexico, is being affected by habitat loss, overuse of its range for such human activities as off-road vehicle operation and harvesting for the pet trade, among other factors. Two other populations of Southwestern tortoises in Colorado and the Mojave desert were given ESA listings in 1990. Read more here.