Ranchers question butterfly listing

The Natural Resource Weekly Report
Dan Berman, Land Letter staff writer

The Fish and Wildlife Service added the only two known populations of the Carson wandering skipper to the Endangered Species List last week in order to protect the species from development, grazing and other human activities in California and Nevada. But some ranchers and others in the region affected by the listing say the agency lacked sufficient data to grant protected status for the butterfly.

The small, tawny orange butterfly is at tremendous risk of extinction due to encroaching development, livestock grazing, off road vehicle activity, changes in the water table, and pesticide drift.

The FWS gave the butterfly emergency protection under the ESA last November, and after studying the species this year, determined a permanent listing is warranted. “We know of only two populations of the skipper, and both are threatened with habitat destruction,” said Robert Williams, supervisor of the FWS Nevada office.

“We are very pleased that the Fish and Wildlife Service can now take action to protect this butterfly,” said Scott Hoffman Black, executive director of the Xerces Society. “Without immediate action, we will have one less beautiful little butterfly. It would be a sad event to let this species go extinct.”

The two populations are outside of Carson City, Nevada and near Honey Lake in Lassen County, Calif. Hoffman Black said a third population in Carson, Calif., was destroyed when an offramp from Interstate 80 constructed adjacent to the skipper’s habitat altered water patterns to the saltgrass that is crucial for the butterfly’s survival.

Saltgrass requires an infinite amount of water in late spring, and alteration of water flow patterns can doom the habitat, and therefore the species, said Mace Vaughan, staff entomologist for the Xerces Society. “The Carson Wandering skipper has a very tight relationship with its host plant and adjacent nectar sources,” Vaughan said. “Because its habitat requirements appear to be very specific, it will be important that any suitable habitat is protected and surveyed for the butterfly right away.”

But Central California and Western Nevada farmers worry the listing may impact their operations, especially when it comes to grazing, and say the listing is politically motivated and not scientifically-based, said Becky Sheehan, legal council for the California Farm Bureau Federation.

Sheehan said scientists have little information to warrant the ESA listing. “They don’t know how many were in this area historically, they don’t know how many are there now,” Sheehan said. “This isn’t how these kinds of decisions should be made.”

As for grazing, Sheehan again said scientists do not have any information on how grazing has impacted the skipper, and defended the ability of farmers to act in an environmentally responsible manner. “Our farmers and ranchers are good land managers and see grazing as a healthy tool to manage the environment … they have been able to work in harmony [with the skippers],” Sheehan aid.

But Hoffman Black said limiting grazing may be necessary to save the skippers. “Because the populations are so small, grazing could have an impact, because if you’re grazing at the wrong time, they could crush [the skipper’s] habitat.” Hoffman Black also expressed concern that cows could eat nectar sources important to the skipper. Hoffman Black admitted that researchers do not yet know enough to determine when grazing should be halted, but guessed it would be in the early spring, before the butterflies emerge in mid-summer. The skipper generally appears for about a month around June, when adults search for flower nectar to feed upon.

“The listing will bring attention to the butterfly so we can learn its life history and better protect it,” Hoffman Black said, calling for a “viable recovery plan” and a critical habitat designation in areas with existing saltgrass.