By Robert Kunzig, Tuesday, November 23, 2021
Is there anyone who doesn’t like butterflies? Bees are emblems of industriousness and admirable enough, but butterflies are small flashes of color and delight. When I see one on the bush at our mailbox, it sends a signal to my unconscious that something is right with the world. But lately, butterflies have also become a sign of what’s wrong. They’re easier to identify and count than most insects—which has made them good indicators of the broader phenomenon of insect decline.
Across Europe, Bridget Huber writes for us this week, the abundance of grassland butterflies has dropped nearly two-fifths since 1990. In Catalonia, Spain (pictured above), where Huber went to report her story, the decline has been more than 70 percent. What’s driving the loss of butterflies, Huber explains, is the loss of small farms. When the farms go, so do the places that support flowers and pollinators like butterflies: the pastures and meadows and uncultivated margins of fields.
In Catalonia and elsewhere, the threat to those farms comes from two directions. Sometimes small farms get absorbed into larger industrial operations that erase the places for wildlife, planting corn or another monoculture right up to the road and spraying pesticides liberally.
But sometimes, Huber writes, the problem is too little human intervention: Farms simply get abandoned. Pastures and hay meadows revert to woods. A quarter of Spain is forested now, three times more than in 1900, which sounds like a triumphant return of nature, and in some ways no doubt is—but it’s not a triumph for butterflies, most of which live on grasslands. Biologist Constantí Stefanescu has been documenting their decline in Catalonia for 25 years. “Forest encroachment is one of the reasons behind this collapse,” he told Huber.
The situation is dire—but not hopeless.
Earlier, Huber reported from Bavaria on efforts to reform agriculture in that conservative German state—efforts that started with a grassroots petition and culminated in a new state law. The law mandates delayed mowing on some meadows to protect butterflies and other insects, preserving hedges and uncultivated corridors along streams, and tripling the area of organic farms, to 30 percent of all farmland in Bavaria, by 2030.
In Catalonia, there’s no such law yet. But a nonprofit called Paisatges Vius is negotiating with individual farmers to create butterfly “micro-reserves” (one, pictured above, on 10 acres of abandoned farmland). Persuade one rancher to mow later or less, and a rare butterfly gets to finish its life cycle. Ranchers and butterflies aren’t born enemies, after all; the ranches are what keep the forest at bay.
“The highest level of diversity is reached when there is collaboration,” Stefanescu says.
(Sources: National Geographic)
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