Logging cuts both ways for rare butterfly: Thinning keeps food source alive, but intense harvesting harms habitat
By: Mateusz Perkowski, Capital Press
August 25, 2011
Logging may pose a threat to a rare butterfly in Oregon — but it may also be instrumental in saving the species.
The seemingly contradictory effects of logging on the Leona’s little blue butterfly are especially relevant now that the federal government is thinking about protecting it under the Endangered Species Act.
Intense harvesting may harm the butterfly, but experts say the species’ potential listing under ESA probably wouldn’t preclude logging on a 90,000-acre private tree farm that comprises its primary habitat.
The butterfly is thought to have a love-hate relationship with logging, according to the Xerces Society, a non-profit insect preservation group that petitioned for the species’ listing.
Some associated activities — like road building, slash piling and heavy equipment operations — may negatively impact the tiny butterfly’s habitat, said Sarina Jepsen, the group’s ESA program director.
However, logging can also prevent meadows from being overwhelmed by conifers that shade out spurry buckwheat, a plant that’s critical to the butterfly’s survival, she said.
The species feeds exclusively on spurry buckwheat during its caterpillar stage and adults also eat nectar from its flowers, Jepsen said. Fire suppression efforts in the past half century may have allowed for forest encroachment onto areas that were traditionally meadows.
Though the plant grows in other regions, the butterfly has only been found in a 6-square-mile area east of Crater Lake in southern Oregon, she said. A small portion of the species’ range is on national forestland, but most of it’s on the tree farm.
It’s possible the butterfly’s habitat correlates with ash and pumice deposits from the explosion of Mount Mazama — the volcano that erupted roughly 7,000 years ago, leading to the formation of Crater Lake, Jepsen said.
Exactly why the species would rely upon this unique geology is unclear, however, she said. “There’s quite a lot that’s not known about this butterfly.”
The species’ total population is estimated to be between 1,000 to 2,000 butterflies, but that’s based on only three years of survey data, Jepsen said. “We don’t have long-term data on the population trends.”
At this point, the U.S. Fish and Wildlife Service has only agreed that the species warrants further study to determine whether it’s actually threatened or endangered, said Laurie Sada, field supervisor for the agency’s office in Klamath Falls.
“This is not a listing. We’re just saying the petition has good information that should be evaluated further through the public process,” she said.
The agency is asking for the public to submit additional information about the butterfly, which will be used to decide if the species should be listed under ESA in about one year, Sada said.
When a threatened or endangered species resides on private land like the tree farm, property owners can be held liable for violating the ESA if they harm the species or its habitat without a permit, said Elizabeth Howard, an natural resources attorney with the Dunn Carney law firm.
To obtain such a permit, landowners must abide by a “habitat conservation plan” that aims to mitigate hazards to the species — potentially altering land management practices, she said.
“It’s basically an agreement between the private landowner and the U.S. Fish and Wildlife Service,” Howard said.
There’s currently another option on the table.
Fidelity National Timber Resources, the tree farm’s parent company, is working with several researchers to develop a voluntary conservation plan for the tree farm.
“We don’t know the details, but the areas where the butterflies are have already been cut,” Nancy Craven, executive vice president of the company.
The plan would allow the tree farm’s managers to voluntarily implement mitigation measures, potentially averting the need for listing altogether, said Sada.
This scenario has previously played out with another butterfly species that has a very small range — the Nevada Sand Mountain blue butterfly — she said. The species inhabits about 1,000 acres of sand dunes in one Nevada county.
“These kinds of agreements can be successful with a narrowly endemic species, with one or two landowners,” Sada said.