From the U.S. Geological Survey
Efforts to mitigate the effects of natural gas development are leading to better nest survival for greater sage-grouse. The probability of one egg hatching in a particular nesting season is higher compared to areas where such actions were not taken, according to research recently published in the journal Wildlife Biology.
The article is co-authored by Laura Bond, bioinformatics coordinator in Boise State’s Biomolecular Research Center, and researchers with the USGS and Big Horn Environmental Consultants. It is the first to look at the application of science-based on-site mitigation techniques and sage-grouse nest survival in the Intermountain West.
Mitigation techniques are actions taken to reduce or offset the impacts of human activities on an ecosystem or a species, such as minimizing sagebrush removal and using remote monitoring of wells to reduce vehicle traffic.
“High nest survival is critical to the species’ continued existence,” said USGS emeritus scientist and co-author Mark Fuller. “These are ground-nesting birds that produce on average 6-10 eggs each year. Their nests are vulnerable to predation and other factors, making it difficult for the greater sage-grouse populations to maintain numbers.”
Sagebrush habitat is increasingly being developed for oil and gas resources, and land managers face complex challenges in balancing energy demands with conservation measures for sagebrush-dependent species such as the greater sage-grouse. Agencies responsible for managing sagebrush habitat and greater sage-grouse populations encourage the use of adaptive management measures, such as science-based mitigation during oil and gas development and operations.
From 2008 to 2011, scientists monitored greater sage-grouse nests in a natural gas field in the Powder River Basin, Wyoming. An oil and gas developer, in cooperation with the Bureau of Land Management, applied adaptive management measures to reduce impacts to greater sage-grouse and other wildlife. Researchers measured nest survival in mitigated and non-mitigated areas, as well as in relatively unaltered areas without oil and gas development. Nest survival was determined by the evidence of at least one successfully hatched egg, a standard measurement in avian scientific studies.
The scientists discovered that on-site mitigation techniques increased the number of surviving greater sage-grouse nests relative to areas where no mitigation techniques were applied. Among mitigation techniques studied, piping discharge water to a treatment facility instead of constructing an on-site reservoir resulted in higher nest survival in the surrounding area.
“One theory is that reservoir water attracts new predators such as the striped skunk to the area where they eat greater sage-grouse eggs and destroy the nest,” said Chris Kirol, a research biologist with Big Horn Environmental Consultants and lead author of the study.
“Although we did find that nests located in areas outside of energy development had the highest survival rates, which agrees with the larger body of sage-grouse research, properly targeted mitigation techniques can benefit greater sage-grouse nest survival,” said Kirol. “Our results can help inform future adaptive management and greater sage-grouse conservation efforts in sagebrush habitat affected by energy development.”
Greater sage-grouse live in parts of 11 states and two Canadian provinces in western North America. The U.S. Fish and Wildlife Service is formally reviewing the status of greater sage-grouse to determine if the species is warranted for listing under the Endangered Species Act.
BY: KATHLEEN TUCK PUBLISHED 4:15 PM / MARCH 1, 2015