DUSTIN BLEIZEFFER Star-Tribune energy reporter | Posted: Thursday, September 7, 2006 12:00 am
GILLETTE - Prolonged hot weather is taking its toll once again on sage grouse in the Powder River Basin, where it has been confirmed that five radio-collared birds died of West Nile virus recently.
Hot weather has also contributed to significant West Nile virus mortality in sage grouse populations in California, Idaho and Oregon as well, signaling a persistent threat for the species across the West.
"We now should consider West Nile virus an endemic source of mortality (among sage grouse) that we're going to have to deal with for a long time," said David Naugle, a professor of biology at the University of Montana. "Don't plan on this going away. It's another source of mortality for sage grouse long term."
Naugle oversees current research of sage grouse populations in northeast Wyoming and southeast Montana, where there's significant energy development - chiefly coal-bed methane. Production of that gas has increased surface water and created habitat with potential for an increase in mosquitoes and biting midges. Those insects are potential carriers of viruses such as West Nile.
Naugle said the persistence of West Nile virus mortality among sage grouse is particularly disconcerting given the fact that Wyoming is a stronghold for the bird, yet there are plans for intense energy development throughout much of the state's prime sage grouse habitat.
Sage grouse don't like to move significant distances, Naugle said, and his research has indicated that populations that do stay within energy development areas - such as the Powder River Basin - experience high death rates.
"The only way to buffer wildlife from diseases is to give them lots of high-quality habitat so that in the good years they have a chanced to rebound," Naugle said.
So far, there are no protections in place specific to sage grouse. However, many energy companies in the state voluntarily re-seed well pads and pipeline corridors with native forbs to help improve sage grouse habitat, and they design water reservoirs to discourage mosquitoes.
Tom Maechtle, owner of Big Horn Environmental Consulting, also serves as chairman of the Northeast Wyoming Sage Grouse Working Group. He said energy companies - particularly coal-bed methane developers - are actively taking on such mitigation measures.
"In some ways, the energy sector has an opportunity to invigorate the growth of native forbs, which could improve habitat for sage grouse over time," Maechtle said.
Maechtle said the sage grouse working group will present preliminary recommendations to the Wyoming Game and Fish Commission on Thursday regarding the protection of sage grouse. In addition to habitat restoration, the group will recommend stocking coal-bed methane water reservoirs with native fish, such as the fathead minnow, known to feed on the mosquito larva known to carry West Nile virus in the Powder River Basin region.
Naugle said this year's outbreak debunks the notion that a 25 percent mortality rate in 2003 was a flash-in-the-pan situation. Industry leaders had argued that it was an anomaly because the mortality rate declined to 10 percent in 2004 and 2 percent in 2005.
Naugle said he believes this summer's West Nile virus outbreak suggests that any time there's a prolonged period of heat, sage grouse are more susceptible to the disease. That means sage grouse that live in areas of significant energy development are in double-jeopardy.
"(Sage grouse) don't move around very well, and it's a bad thing to move wildlife around," Naugle said.
Energy reporter Dustin Bleizeffer can be reached at (307) 682-3388 or dustin.bleizeffer@casperstartribune.net.