Climate Change May Pose Substantial Future Risk to Sagebrush Habitat in Southwestern Wyoming plus 1 more

[USGS Newsroom <noreply+feedproxy@xxxxxxxxxx>]

Title: USGS Newsroom

Climate Change May Pose Substantial Future Risk to Sagebrush Habitat in Southwestern Wyoming plus 1 more

---

Climate Change May Pose Substantial Future Risk to Sagebrush Habitat in Southwestern Wyoming

Posted: 10 Apr 2015 07:00 AM PDT

Summary: Climate change may pose a substantial future risk for sagebrush habitat in southwestern Wyoming, and thus adversely affect the regional summer habitat and nesting areas of sage-grouse, according to a new study by the United States Geological Survey

---

Contact Information:

Catherine Puckett ( Phone: 352-377-2469 );

---

Sioux Falls, SD. — Climate change may pose a substantial future risk for sagebrush habitat in southwestern Wyoming, and thus adversely affect the regional summer habitat and nesting areas of sage-grouse, according to a new study by the United States Geological Survey.  

For the study, scientists used nearly 30 years of Earth observation data to analyze past climate patterns in 3,216 square miles (8,330square kilometers) of southwestern Wyoming to forecast sagebrush abundance in 2050. Wyoming is a stronghold for populations of greater sage-grouse, a species being considered for listing as threatened or endangered by the U.S. Fish and Wildlife Service. The species is dependent upon sagebrush habitat.

“Historic disturbances of fire, development and invasive species have altered the sagebrush landscape, but climate change may represent the habitat’s greatest future risk,” said Collin Homer, the USGS scientist who led the study. “Warming temperatures, combined with less snow and rain, will favor species other than sagebrush, as well as increase sagebrush habitat’s vulnerability to fire, insects, disease and invasive species.”

The authors noted that intact, healthy sagebrush systems increase sage-grouse resilience to negative effects of climate change whereas less intact and more marginal habitats decrease the species’ resilience.

Homer and his colleagues examined the impact of historical precipitation change on key components of sagebrush ecosystems from 1984 to 2011. These historical patterns, discerned from long-term records of the Landsat satellite series (a joint effort of USGS and NASA), were then combined with IPCC (Intergovernmental Panel on Climate Change) precipitation scenarios to model and forecast the most likely changes in sagebrush habitat from 2006 to 2050.

Researchers found that projected precipitation patterns for 2050 resulted in decreasing amounts of sagebrush and other shrubs, grasses, and flowering plants (forbs), while increasing the amount of bare ground.  When these changes were translated to sage grouse habitat, researchers found this resulted in a potential loss of 12 percent of sage-grouse nesting habitat and about 4 percent of sage-grouse summer habitat by 2050.  Results also demonstrate the vulnerability of semi-arid lands, such as sagebrush habitat, to precipitation changes because of their already low soil moisture content.

This new research explores how to bring climate change results to a more localized scale, in this case units as small as a quarter of an acre. “Using Landsat and downscaled climate scenarios to enable future forecasts of greater sage-grouse habitat can provide critical information on a more local or regional scale for managers to help them better plan now for the future,” said Homer.

Greater sage-grouse occur in parts of 11 U.S. states and two Canadian provinces in western North America.  These birds rely on sagebrush ecosystems, which constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. 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.

Dynamic Dead Zones Alter Fish Catches in Lake Erie

Posted: 09 Apr 2015 11:00 AM PDT

Summary: New research shows that Lake Erie’s dead zones are actually quite active, greatly affecting fish distributions, catch rates and the effectiveness of fishing gear

---

Contact Information:

Marisa Lubeck, USGS ( Phone: 303-202-4765 ); Irene Miles, Illinois-Indiana Sea Grant ( Phone: 217-333-8055 );

---

New research shows that Lake Erie’s dead zones are actually quite active, greatly affecting fish distributions, catch rates and the effectiveness of fishing gear.  

Scientists with the U.S. Geological Survey, the Illinois-Indiana Sea Grant and partners recently found that dead zones caused by hypoxia, the depletion of oxygen in water, are unexpectedly variable in Lake Erie, sometimes disappearing and reemerging elsewhere in the matter of hours. They also found that fish like yellow perch cluster at the edges of these areas. The discovery of erratic dead zones can help commercial fishers and scientists determine where and how to effectively catch and study fish.

The study, conducted near Fairport Harbor, Ohio, during August and September of 2011-2013, was recently published in the Canadian Journal of Fisheries and Aquatic Sciences.

“We were amazed by how quickly hypoxic areas moved during our study,” said Richard Kraus, a USGS scientist and the lead author. “These findings can help managers sustain valuable fish populations in Lake Erie, which is one of the world’s largest commercial fisheries.” 

Hypoxia at the bottom of Lake Erie occurs during the summer as a result of biological activity in the colder bottom layer that consumes dissolved oxygen in the water. The warmer surface layer floats on top, preventing oxygen from mixing down to the bottom. The researchers used sensors to measure oxygen levels and lakebed temperatures, and found that dead zones are frequently moving as a result of internal waves in the lake.

Although bottom waters might be a refuge for cool-water fish species, hypoxia can force fish to seek less suitable habitats. Acoustic surveys during the study revealed that when fish shift because of seasonal hypoxia, they cluster at the edges of dead zones rather than avoiding hypoxic areas entirely. Using fishing gear like trawls and nets, the scientists caught fish at the highest rates along dead zone boundaries. 

“Our study shows that Lake Erie contains a patchwork of low and high-density fish populations,” said Paris Collingsworth, a Great Lakes Ecosystem Specialist with Sea Grant. “This understanding of fish distributions can inform policy decisions, such as how many walleye, yellow perch and others can be fished from the lake.” 

The USGS and Illinois-Indiana Sea Grant partnered with the Ohio Department of Natural Resources, the Ohio State University and the Environmental Protection Agency on the new study. 

For more information, please visit the Department of the Interior’s Northeast Climate Science Center and the Upper Midwest and Great Lakes Landscape Conservation Cooperative websites.