Category Archives: Science to Solutions

Research Says, Adjusting Grazing Practices Can Improve Prairie-Chicken Habitat

When it comes to creating the diverse grassland structure that lesser prairie-chickens need, prescribed burning–and particularly patch-burn grazing–is a go-to, cost-efficient management strategy. But weather conditions in the semi-arid southern Great Plains can stand in the way of implementing prescribed fire plans. That’s why range managers need a variety of conservation practices in their toolbox to create and maintain the mosaic of grassland habitat that lesser prairie-chickens and other grassland-dependent wildlife species depend on.

A new study by researchers at Kansas State University identifies specific grazing practices—targeted forage utilization goals, decreased stocking density, and larger pastures—that create the varied grassland habitat structure that lesser prairie-chickens need. The latest Science to Solutions report from the Natural Resources Conservation Service-led Lesser Prairie-Chicken Initiative describes the research and what it means for on-the-ground management strategies.

Read the Science to Solutions report, “Grazing Practices Foster Diverse Grassland Habitat.”

What the Study Found

Past research has shown that intensive grazing management (standardized forage utilization goals, smaller pastures, and short-duration grazing periods) can harm grassland ecosystem function, and that producers can increase grassland structural diversity by properly adjusting forage utilization goals, decreasing stocking density, and increasing pasture pasture size.

The recently released study, led by John Kraft, is the first to assess whether these structural diversity-producing grazing strategies have a significant effect on lesser prairie-chicken habitat selection.

The new research shows that  non-breeding lesser prairie-chickens preferred grasslands with 35-45% forage utilization and that use steadily declined when forage utilization topped 50%. Breeding females placed all nests in pastures with less than 40% forage utilization, and the greatest number of nests were placed on sites with forage utilization between 0 and 20%. As grazing pressure increased, daily nest survival fell.

Using computer modeling, researchers then investigated how lesser prairie-chickens utilize grasslands managed with grazing strategies known to increase structural diversity. They found that, regardless of the forage utilization value, lesser prairie-chicken habitat use increased significantly with lower stocking densities, and that larger pasture size increased habitat use. Their findings have important implications for range management within the lesser prairie-chicken’s active range in the southern Great Plains.

What it Means for Range Management

Female prairie-chickens nest in habitat with tall, dense vegetation, then move their broods to habitat with more insect-rich forbs and more bare ground, which allows for greater mobility for chicks. When range management does not create adequate grassland structural variety to meet changing seasonal needs, lesser prairie-chicken populations decline. (Photo: David Haukos)

Stocking density is a crucial indicator for maintaining or improving lesser prairie-chicken habitat. Many ranchers have adopted intensive grazing management practices in which pastures are subdivided into smaller paddocks. This increases stocking density and reduces the quality of the resulting habitat for lesser prairie-chickens. Range managers can reduce stocking density by selectively removing cross fencing to make pasture areas bigger, shifting toward a continuous grazing system. While there is much debate on the merits of rotational and continuous grazing systems, the superiority of one system over another in terms of livestock production and ecosystem health is not widely accepted among professionals.

In rangelands that already have the diverse vegetative structure that lesser prairie-chickens require, range managers can maintain large-scale (i.e., across pastures) heterogeneity through a mix of low-to-moderate forage utilization goals between pastures. Small-scale heterogeneity (i.e., within pasture) can be maintained by implementing low stocking densities, greater pasture areas, and shorter deferment periods.

In rangelands where vegetative structure suitable for nesting is limited, or where the most important grass species for nesting are also among the most palatable, longer deferment and rest-rotation may be needed to restore or create advantageous vegetative structure. Further, periodic, year-long deferment is likely essential to maintain the integrity of grazed lands regardless of plant community composition.

The Science to Solutions report identifies specific management practices to improve lesser prairie-chicken habitat–Read them on page 4 of the report.

The bottom line? While the combined effects of prescribed fire and grazing (patch-burn grazing) offer an exceptional tool for optimizing lesser prairie-chicken habitat and livestock production, a particular assemblage of vegetative diversity-promoting grazing practices can help maintain and improve lesser prairie-chicken habitat when range conditions preclude the use of fire.

Patch-Burn Grazing Fires Up Prairie-Chicken Habitat

For lesser prairie-chickens, good habitat is a complex thing. Structural diversity is key, because a prairie-chicken’s habitat needs change with the seasons. While courtship sites (leks) tend toward short-statured vegetation, females prefer to nest in tall, dense grassland vegetation, then move their chicks to more open, forb-dominated, insect-rich habitat.

New research shows that patch-burn grazing creates the mosaic of grassland habitat structure that prairie-chickens depend on. A new Science to Solutions paper from the Lesser Prairie-Chicken Initiative (LPCI) describes the research and its implications for range management.

Read the Science to Solutions story

The research team, led by Jonathan Lautenbach of Kansas State University, addressed two central questions: How does patch-burn grazing influence grassland composition and structure? How do lesser prairie-chickens use the mosaic that patch-burn grazing creates?

Lautenbach found that, throughout the year, females chose vegetation patches where the combined effects of fire and grazing produced vegetation characteristics that matched their changing seasonal needs. Specifically, females selected greater time-since-fire patches (>2-years post-fire) for nesting, 2-year post-fire patches during the spring lekking season, 1- and 2-year post-fire patches during the summer brooding period, and 1-year post-fire units during the nonbreeding season.

Researchers have also found that patch-burn grazing yields good livestock performance by stabilizing weight gain in the face of rainfall fluctuations. That means patch-burn grazing offers a successful strategy to significantly improve both lesser prairie-chicken habitat and livestock production.

Historic Forces: The Dynamic Duo of Fire and Grazing

Historically, fire and grazing acted together to shape prairie vegetation. Ignited by Plains Indians and lightning, fire killed encroaching woody plants and prompted the vigorous re-sprouting and germination of prairie vegetation. This succulent new growth of grasses and forbs attracted herds of large herbivores, which selectively grazed the recently burned area. The resulting landscape was a mosaic of burned areas scattered among grassland patches of varied ages since burning.

Most current range management in the Great Plains decouples fire and grazing. When fire is over-applied (for example, by burning entire pastures), livestock don’t have the choice between burned and unburned prairie, and a uniform grassland structure results. On the other end of
the management spectrum, fire suppression also reduces grassland structural and species diversity.

Grassland uniformity reduces drought resiliency, which decreases livestock productivity. Uniformity also negatively impacts grassland wildlife, particularly grassland birds, since some species require varying vegetation structure across the landscape to complete their life cycles.

Further, without regularly occurring fires, fire-intolerant woody plants encroach, significantly reducing both livestock forage and grassland wildlife habitat (see LPCI’s Science to Solutions #1 on redcedar encroachment and Science to Solutions #3 on mesquite encroachment).

Male lesser prairie-chicken on a lek (mating display area) within the patch-burn grazing study area. The lek site had been burned just three days earlier. Photo: Jonathan Lautenbach.

What the Science Means for Management

The Natural Resources Conservation Service-led Lesser Prairie-Chicken Initiative provides technical and financial assistance to farmers and ranchers to voluntarily improve habitat for lesser prairie-chickens. Lautenbach’s study, funded in part by LPCI, helps identify which range management strategies are most effective in benefitting bird and herd.

Patch-burned pasture within Lautenbach’s study site on the Hashknife Ranch in south-central Kansas.

Past research has shown the clear benefits of patch-burn grazing on livestock productivity. Specifically, cattle in pastures with two or more patches gained weight independent of rainfall, indicating that patch-burn grazing helps buffer climatic variation and stabilizes livestock productivity—a critically important attribute in the drought- prone southern Great Plains.

Also, research shows that, while both conventional prescribed burning and patch burning reduce wildfire fuels and redcedar encroachment, patch-burning does so while maintaining habitat for grassland-dependent wildlife.

Lautenbach’s study adds to evidence of the win-win nature of patch-burn grazing for livestock and wildlife, specifically showing that lesser prairie-chickens use the diverse patchwork to meet their needs for nesting, brood- rearing, and over-wintering.

The findings show that the scale and configuration of prescribed burns really matter. During the study, no females were observed nesting in year-of-fire patches, which lack thermal and hiding cover. Creating a mosaic of grassland patches of varied age-since-fire (rather than conventional whole-pasture burning) is a crucial part of the conservation equation.

To achieve the combined conservation strategies of removing redcedar and increasing grassland heterogeneity, Lautenbach’s research team recommends implementing prescribed fire in a patch-burn grazing system with a 4-6 year burn interval for any given patch.

The researchers note that their study was conducted in the eastern portion of the lesser prairie-chicken’s distribution. Regional differences in rainfall, soil types, and vegetation, create four different eco-regions, across the lesser prairie- chicken’s occupied distribution in the southern Great Plains. Within these ecoregions the recommended fire return interval will change, with areas receiving less rainfall having a greater fire-return interval (e.g. 7-10 years for any given patch).

Check out all of LPCI’s Science to Solutions papers on LPCI’s Resources page.

Science to Solutions: New Mapping Tool Helps Target Woody Encroachment

Lesser prairie-chickens avoid prairie habitat with just one redcedar per acre. In the southwestern part of their range, they strongly prefer sites with less than one percent mesquite cover. Range managers need to be able to detect very low densities of encroaching woody plants on the landscape  to target effective conservation efforts. The Lesser Prairie-Chicken Initiative’s latest Science to Solutions paper describes a new mapping tool that offers that capacity and more.

Read SCIENCE TO SOLUTIONS: New Mapping Tool Helps Target Woody Encroachment

The new, high-resolution mapping tool will allow range managers to evaluate the landscape-level impacts of woody encroachment on both lesser prairie-chicken and greater sage-grouse habitat even at very low densities. This precise information helps target conservation actions and monitor results.

A team of scientists from USDA Natural Resources Conservation Service, Colorado State University, The Nature Conservancy, University of Wyoming, University of Montana, Oregon State University, US Geological Survey, University of Minnesota, and New Mexico State University produced the mapping tool.

A  research paper on the mapping tool and its applications was published earlier this month in a special edition of Rangeland Ecology & Management, the scientific journal of the Society for Range Management, focused on the effects and management of woody encroachment as it relates to habitat for lesser prairie-chickens and greater sage-grouse.

A full-day symposium on the research showcased in the January 2017 issue of Rangeland Ecology & Management will take place on January 31, 2017, at the Society for Range Management annual conference. The symposium will be live-streamed on the Sage Grouse Initiative website (live-streaming is free and open to the public).

LPCI’s Science to Solutions summary explains the tool and its applications, particularly as it relates to lesser prairie-chicken habitat conservation.

SCIENCE TO SOLUTIONS: LPCI Conservation Practices Boost Lesser Prairie-Chicken Occupancy

Habitat conservation practices make a difference for lesser prairie-chickens. That’s the finding of a recent scientific study—the first part of a multi-year study—described in a new report from the Lesser Prairie-Chicken Initiative (LPCI).

LPCI, led by USDA’s Natural Resources Conservation Service (NRCS), works with partner screen-shot-2016-10-17-at-10-52-52-amorganizations and ranchers to improve habitat and address threats to the bird. Since 2010, more than 1 million acres of habitat in the southern Great Plains have been restored on working lands.

NRCS works with partners to monitor the outcomes of targeted assistance to private landowners, which helps determine if LPCI’s conservation practices are making a difference. However, accurately estimating wildlife populations be challenging with uncommon, widely dispersed species like the lesser prairie-chicken.

A recent study identified a new model for assessing lesser prairie-chicken populations, and it shows encouraging evidence that NRCS-recommended conservation practices through LPCI are working and that large blocks of intact prairie are important to prairie-chicken conservation.

Download the new Science to Solutions report.

The study assessed one year of data from the annual aerial survey of lesser prairie-chicken lek sites conducted by the Western Association of Fish and Wildlife Agencies, and it looked at four factors that might impact site occupancy—patch size of native vegetation, percent of land cover managed with prescribed grazing; percent of land cover enrolled in the USDA’s Conservation Reserve Program (CRP); and density of primary roads. The research team intends to continue with a multi-year study that assesses additional variables.

Lesser prairie-chickens face many threats, including habitat loss and fragmentation from row-crop agriculture, fire suppression, unmanaged grazing, development, and drought. The species currently occupies just 16 percent of its historic range.

2015-survey-grid-lowres-copy

Map of current and historical range of the lesser prairie-chicken, showing sites surveyed during the 2013 range-wide aerial survey. The data from this survey was repurposed to assess LEPC habitat occupancy. (Click on map for larger view).

But in western Kansas, lesser prairie-chickens have reoccupied portions of their historical range and have even moved into areas outside that historical range. The range expansion coincides with former croplands enrolled and maintained as grasslands through CRP, as well as native grasslands managed using LPCI prescribed grazing practices.

A team of researchers tested whether there was a quantifiable link between land managed with prescribed grazing or enrolled in CRP and the likelihood of prairie-chickens occupying a landscape. Their results indicate that these habitat conservation efforts are working.

After developing an expanded model for assessing lesser prairie-chicken populations, the team found that occupancy increases as prairie patch-size increases, as well as in landscapes with ongoing conservation practices. Specifically, the results indicate that when lands are using prescribed grazing or enrolled in CRP, the likelihood of lesser prairie-chickens occupying that habitat increases significantly.

The report’s management recommendations include:

  • Enrolling acreage within the lesser prairie-chicken active range in prescribed grazing or CRP.
  • Maintaining large blocks of native prairie across the range through sustainable ranching.
  • Identifying potential landscapes with willing landowners to develop conservation easements, particularly if combined with prescribed grazing and other proven habitat conservation practices.
  • Implementing prescribed grazing on dispersed patches throughout large blocks of rangeland.
  • Cultivating diverse stands of CRP-enrolled grasslands that serve as connective tissue to larger patches of native prairie.
  • Retaining CRP acreage as grasslands after contract expiration.
Lesser prairie-chickens benefit from LPCI prescribed grazing. The study showed strong positive relationship between percent prescribed grazing and probability of occupancy.

Lesser prairie-chickens benefit from LPCI prescribed grazing. The study showed strong positive relationship between percent prescribed grazing and probability of occupancy.

NRCS outlined its three-year plan for lesser prairie-chicken conservation in its Lesser Prairie Chicken Initiative FY16-18 Conservation Strategy report, which encourages adoption of many of the above practices—such as prescribed grazing, using easements to protect key habitat corridors, and providing assistance to convert expiring CRP lands to grazing—on 500,000 additional acres.

Learn more about these findings by downloading the new Science to Solutions report. This report is part of the Science to Solutions series offered through NRCS, LPCI and the Sage Grouse Initiative.

 

 

SCIENCE TO SOLUTIONS: Redcedar Removal Restores Lesser Prairie-Chicken Habitat

The science is in! A new study by researchers from Kansas State University and US Geological Survey resoundingly confirms that redcedar encroachment on the Southern Great Plains greatly impacts lesser prairie-chickens.

Screen Shot 2016-03-24 at 9.56.18 AMRead our Science to Solutions report about the study and the LPCI management recommendations the study informs.

Using GPS transmitters, researchers tracked the movements of 58 female lesser prairie-chickens  for two years on 35,000 acres of private land in south-central Kansas. They measured the response of the prairie-chickens to trees 3 feet or taller, 80% of which were eastern redcedars. Three key findings emerged:

  • Female lesser prairie-chickens did not nest in grasslands with more than 1 tree per acre.
  • They avoided trees by about 1000 feet on average when selecting habitat and nest sites.
  • They stopped using grasslands altogether when tree density reached 3 trees/acre.

LEPCs in the study area were forty times more likely to use habitats with tree densities of 0 trees/acre than habitats with 2 trees/acre. The findings make it clear that removing redcedar, even when present at very low densities, is critical to LEPC conservation.

The Lesser Prairie-Chicken Initiative (LPCI) uses science to develop management practices that will most efficiently and effectively improve habitat for lesser prairie-chickens, delivering the greatest return on investment.

In response to this latest study, LPCI has released its first Science to Solutions paper, “Redcedar Removal Restores LEPC Habitat,” identifying conservation practices aligned with these scientific findings. The recommendations center on three key strategies:

  • Focus on stands with low-density redcedar encroachment, giving priority to sites within LEPC focal areas and connectivity zones, and sites already occupied by LEPC or adjacent to occupied sites.
  • Use mechanical cutting or prescribed fire to remove all redcedar trees on treated acres.
  • Use prescribed fire to maintain or restore open grasslands. Regular use of prescribed fire is a cost-effective way to prevent woody encroachment on grasslands.

Read the full Science to Solutions paper for details!