Abstract
The reduction and simplification of grasslands has led to the decline of numerous species of grassland fauna, particularly grassland-obligate birds. Prairie-chickens (Tympanuchus spp.) are an example of obligate grassland birds that have declined throughout most of their distribution and are species of conservation concern. Pyric herbivory has been suggested as a land management strategy for enhancing prairie-chicken habitat and stabilizing declining population trends. We assessed differences in vegetation structure created by pyric herbivory compared to fire-only treatments to determine whether pyric herbivory increased habitat heterogeneity for prairie-chickens, spatially or temporally. Our study was performed at four sites in the southern Great Plains, all within the current or historic distribution of either lesser (T. pallidicinctus), greater (T. cupido), or Attwater’s (T. cupido attwateri) prairie-chickens. Key vegetation characteristics of grass cover and vegetation height in pyric herbivory and fire-only treatments were within the recommended range of values for prairie-chickens during their distinct life history stages. However, patches managed via pyric herbivory provided approximately 5% more forb cover than fire-only treatments for almost 30 months post-fire. Additionally, pyric herbivory extended the length of time bare ground was present after fires. Pyric herbivory also reduced vegetation height and biomass, with mean vegetation height in pyric herbivory treatments lagging behind fire-only treatments by approximately 15 months. Canopy cover in fire-only treatments exceeded levels recommended for prairie-chicken young within 12 months post-fire. However, canopy cover in pyric herbivory treatments never exceeded the maximum recommended levels. Overall, it appears that pyric herbivory improves vegetation characteristics reported as critical to prairie-chicken reproduction. Based on our results, we suggest pyric herbivory as a viable management technique to promote prairie-chicken habitat in the southern Great Plains, while still accommodating livestock production.
Highlights
Over the past century, rangelands have declined worldwide, primarily as a result of anthropogenic land use change [1]
To assess the shifting mosaic both spatially and temporally, we developed a large-scale experiment on sites within the historical distributions of lesser, greater, and Attwater’s prairie-chickens across the diverse ecoregions of the southern Great Plains
Data were collected from Aransas National Wildlife Refuge (Special Use Permit # 21530-1506-DI), Attwater Prairie-chicken National Wildlife Refuge (Special Use Permit # ATW-14004), Packsaddle Wildlife Management Area, and the Tallgrass Prairie Preserve
Summary
Rangelands (grasslands, shrublands, and savannas) have declined worldwide, primarily as a result of anthropogenic land use change [1]. In the Great Plains of North America, past rangeland management practices have reduced the quality of remaining habitat for prairie-chickens [3, 4]. In areas where fire frequency increased (large-scale annual burning in the Flint Hills of Kansas), structural and compositional vegetation characteristics became simplified, often with a net result of lower biodiversity [4, 6, 7]. Areas where fire frequency decreased (virtually the entirety of the Great Plains with the exception of the Flint Hills) were invaded by woody species [4,5,6,7,8]. Evidence suggests a wide range of vegetation structure is essential for conservation of this suite of birds [12,13,14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
