Adaptive Management in Native Grasslands Managed by the U.S. Fish and Wildlife Service—Implications for Grassland Birds

Open-File Report 2018-1152
Prepared in cooperation with the U.S. Fish and Wildlife Service
By: , and 

Links

  • Document: Report (7.60 MB pdf)
  • Appendixes:
    • Appendix 1 (1.10 MB pdf) Testing the influence of management regime and year on vegetation structure variables on two grass types on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 2 (1.03 MB pdf) Testing the influence of post-management treatments on vegetation structure variables on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 3 (1.76 MB pdf) Testing the influence of management regime and year on floristic composition variables collected on two grass types on Federal lands managed under an adaptive- management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 4 (1.25 MB pdf) Testing the influence of post-management treatments on vegetation composition variables on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 5 (4.46 MB pdf) Testing the influence of management regime and year on breeding densities (pairs per 100 ha) of 35 common bird species and grassland bird species of conservation concern on two grass types on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 6 (2.21 MB pdf) Testing the influence of post-management treatments on breeding densities (pairs per 100 ha) of 35 common breeding bird species and grassland species of conservation concern on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
    • Appendix 7 (463 kB pdf) Model selection results for candidate sets of models relating vegetation structure and vegetation composition and other variables to breeding densities (pairs per 100 ha) of 23 common breeding birds species and grassland species of conservation concern on Federal lands managed under an adaptive-management framework by the U.S. Fish and Wildlife Service in North Dakota, South Dakota, Minnesota, and Montana, 2011–13
  • Data Release: USGS data release – Adaptive management in native grasslands managed by the U.S. Fish and Wildlife Service: Implications for grassland birds, 2011–2013 data release
  • Download citation as: RIS | Dublin Core

Abstract

Burning and grazing are natural processes in native prairies that also serve as important tools in grassland management to conserve plant diversity, to limit encroachment of woody and invasive plants, and to maintain or improve prairies. Native prairies managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region of the northern Great Plains have been extensively invaded by nonnative, cool-season species of grasses. These invasions were believed to reflect a common management history of long-term rest and little or no defoliation by natural processes (burning and grazing). To address the challenges associated with these invasive species, the FWS embraced a collaborative approach in 2008, in partnership with U.S. Geological Survey, to restore native prairies on lands managed by FWS. This approach is known as the Native Prairie Adaptive Management (NPAM) initiative and was based on the application of an adaptive decision-support framework to assist managers in selecting management actions despite uncertainty and in maximizing learning from management outcomes. The primary objective of this approach was to increase the composition of native grasses and forbs on native, unbroken sod while minimizing costs. The alternative management actions that were used to meet this objective include grazing, burning, burning and grazing, and rest (no action).

A major challenge for FWS resource managers participating in the NPAM initiative was the recognition that other taxa, besides native grasses and forbs, may be affected by the alternative management practices, thus complicating the adaptive-management cycle and deepening the uncertainty. Specifically, many grassland birds are sensitive to changes in vegetation composition and structure, and thus management that alters vegetation also may affect bird populations. The primary objectives of this study were to assess the effects of alternative management actions on grassland birds on FWS-owned grasslands that are managed under the adaptive-management framework, and to assess the association of vegetation structure and composition as mechanisms for triggering grassland bird responses to management.

We surveyed breeding birds and sampled vegetation on 89 native prairie NPAM units managed by the FWS during 2011–13, including 55 units in 2011, 87 units in 2012, and 87 units in 2013. The NPAM units were in 19 FWS refuge complexes and wetland management districts, including 14 complexes in FWS Region 6 (North Dakota, South Dakota, and Montana) and 5 complexes in FWS Region 3 (Minnesota). Generalized linear mixed models were used to evaluate the effects of management actions on vegetation structure, vegetation composition, and densities of common bird species. Vegetation structure and composition varied among study units and years, and many of these differences were linked to specific management activities or to the recency of those activities. We recorded 110 bird species in the 89 adaptive-management units. Models of bird abundance reflected not only disturbance-derived changes in vegetation structure and species-specific vegetation preferences but also the influence of defoliation treatments. Vegetation composition was less important to grassland birds than vegetation structure; in particular, mean vertical obstruction (vegetation height-density), bare-ground cover, and litter depth positively or negatively influenced densities of some grassland bird species. The diversity of bird responses to management in this study underscores the complexity of natural grassland systems and the need for heterogeneity management in grasslands in this region.

Suggested Citation

Igl, L.D., Newton, W.E., Grant, T.A., and Dixon, C.S., 2018, Adaptive management in native grasslands managed by the U.S. Fish and Wildlife Service—Implications for grassland birds: U.S. Geological Survey Open-File Report 2018–1152, 61 p., https://doi.org/10.3133/ofr20181152.

ISSN: 2331-1258 (online)

Study Area

Table of Contents

  • Acknowledgments
  • Abstract
  • Introduction
  • Objectives
  • Study Area and Methods
  • Vegetation and Bird Responses to Adaptive Management
  • Implications for Grassland Birds
  • Summary
  • References
  • Appendixes 1–7

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title Adaptive management in native grasslands managed by the U.S. Fish and Wildlife Service—Implications for grassland birds
Series title Open-File Report
Series number 2018-1152
DOI 10.3133/ofr20181152
Year Published 2018
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Northern Prairie Wildlife Research Center
Description Report: viii, 59 p.; Appendixes 1-7; Data Release
Country United States
State Minnesota, Montana, North Dakota, South Dakota
Other Geospatial Prairie Pothole Region
Online Only (Y/N) Y
Additional Online Files (Y/N) Y