Wildlife officials are appealing to landowners on San Juan and Lopez islands. They’re asking them to set aside patches of habitat for the rare island marble butterfly, before it gets official protection under federal law.
It’s been more than a year and a half since this fuzzy green and white insect was proposed for protection as an endangered species. The island marble was thought to have gone extinct a century ago, in 1908. It was rediscovered on San Juan Island in 1998, then seen a few years later on Lopez Island. Both locations provide plenty of prairie grasslands where mustard blossoms grow that the butterflies use for feeding and laying their eggs.
Now, only a few hundred of the butterflies are known to exist in a small area of San Juan Island National Historical Park. None have been seen on Lopez since 2006. The park carries out a year-round captive rearing program to boost the population. The listing is expected to become law around the end of this year.
But officials say that status won’t matter much if people don’t create more places the butterfly can spread into and live out its full life cycle. Right now, there’s a single population hanging on in an area of less than 100 acres.
“We need a broader distribution than that: lots of populations and interacting populations. And to do that we need to have habitat that’s safe for them. So that’s what this is about,” said Hannah Anderson, endangered species section manager for the Washington Department of Fish and Wildlife.
The agency is sending out mailers to about 600 landholders on the two islands, in hopes of getting as many as possible to agree to set aside about 50 square feet per acre of land they have that might appeal to the butterfly.
If they do so before the listing is finalized, they’ll be exempt from enforcement of Endangered Species Act regulations related to the butterfly on the rest of their land, once that becomes law. The state says these patches of habitat will function like little islands that are safe harbors for the island marble and will attract it, making it less vulnerable elsewhere. So, farming and other activities that would likely harm it can continue on the rest of that private land.
One of the trickiest aspects of protecting this butterfly is that, although it only flies for about 10 days in spring, it is present year-round in the form of less-visible eggs, caterpillars and chrysalises that fade into the landscape and can be easily crushed. Landowners who agree to set aside conservation patches will be coached by the state on how to create good habitat, by planting the mustard host plants needed and protecting them from trampling – and from grazing by the island’s abundant deer, who like to eat the very buds that the butterflies use as nests for their eggs.
Anderson says WDFW has cut through a lot of red tape to make this process relatively painless. They’re also emphasizing that joining the conservation effort is a special opportunity.
“We’re building the support network to implement and support the landowners,” Anderson said. “What they do on their property in their place really does contribute to the good of this animal that’s super unique and special to the islands.”
And, she says, getting private landholders to help will have a direct impact on the success of the recovery efforts.
“With a species like this, it’s going to take private landowners to help recover it,” said Kathleen Foley, stewardship manager for the San Juan Preservation Trust, which has been setting aside land and planting field mustard for the rare butterfly for several years now.
Foley says last spring, an island marble finally flew onto one of her organization's habitat patches and laid eggs. She says she was so excited, she did handstands to celebrate. Part of the elation was the realization that landowners can have a direct impact on the fate of a dwindling species.
“It’s not like trying to recover the orca or our salmon runs – where it’s this giant, existential problem that involves so many different layers,” Foley said. “This is something that we can recover quite easily. It’s within our grasp.”
Wildlife officials say over the past 20 years, they’ve had success with conservation agreements similar to this one for dozens of endangered species nationwide. The best example of this in Washington state is the rapidly rebounding Pacific Fisher, for which several private timber companies have agreed to leave trees and snags in place that the fishers use as dens.