Research Papers
Invertebrate Community Response to a Shifting Mosaic of Habitat

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Abstract

Grazing management has focused largely on promoting vegetation homogeneity through uniform distribution of grazing to minimize area in a pasture that is either heavily disturbed or undisturbed. An alternative management model that couples grazing and fire (i.e., patch burning) to promote heterogeneity argues that grazing and fire interact through a series of positive and negative feedbacks to cause a shifting mosaic of vegetation composition and structure across the landscape. We compared patch burning with traditional homogeneity-based management in tallgrass prairie to determine the influence of the two treatments on the aboveground invertebrate community. Patch burning resulted in a temporal flush of invertebrate biomass in patches transitional between unburned and patches burned in the current year. Total invertebrate mass was about 50% greater in these transitional patches within patch-burned pastures as compared to pastures under traditional, homogeneity-based management. Moreover, the mosaic of patches in patch-burned pastures contained a wider range of invertebrate biomass and greater abundance of some invertebrate orders than did the traditionally managed pastures. Patch burning provides habitat that meets requirements for a broad range of invertebrate species, suggesting the potential for patch burning to benefit other native animal assemblages in the food chain.

Resumen

El manejo del apacentamiento se ha enfocado grandemente en promover la homogeneidad de la vegetación a través de la distribución uniforme del apacentamiento, para minimizar las áreas del potrero que son disturbadas severamente o no son utilizadas. Un modelo de manejo alternativo que conjuga el apacentamiento y fuego (por ejemplo, la quema de parches) para promover la heterogeneidad argumenta que el apacentamiento y el fuego interactúan a través de una serie de estímulos positivos y negativos para causar un mosaico de vegetación que cambia en composición y estructura a través del paisaje. Comparamos la quema de parches con el manejo tradicional, que promueve la homogeneidad, en una pradera de zacates altos para determinar la influencia de los dos tratamientos en la comunidad de invertebrados de la superficie del suelo. La quema de los parches resultó en un incremento abundante temporal de la biomasa de invertebrados en los parches en transición entre los parches no quemados y los quemados en el año en curso. La masa total de invertebrados fue aproximadamente 50% mayor en estos parches en transición, dentro de los potreros con quema de parches en comparación con los potreros con manejo tradicional basado en la homogeneidad. Más aun, el mosaico de parches en los poteros con quema de parches contenía un rango más amplio de biomasa de invertebrados y una mayor abundancia de algunos órdenes de invertebrados que los potreros manejados tradicionalmente. La quema de parches provee un hábitat que reúnen los requerimientos para un amplio rango de especies de invertebrados, sugiriendo el potencial de la quema de parches para beneficiar otros ensambles de animales nativos de la cadena alimenticia.

Section snippets

INTRODUCTION

Little remains of the North American Great Plains ecosystem once maintained by the interaction of fire and grazing herbivores. Grassland fragments and management practices that result in homogenous landscapes reduce the ecological value of remaining prairie (Coppedge et al. 2001; Fuhlendorf and Engle 2001). In contrast, heterogeneity, which links pattern in landscapes to ecological processes, should serve as the foundation for conservation and ecosystem management (Pickett et al. 2003).

Study Area and Experimental Design

The study area is located on the Oklahoma State University Research Range, which has its headquarters (lat 36°3′N; long 97°13′W) about 21 km southwest of Stillwater, Oklahoma. The climate is continental with an average frost-free growing period of 204 d extending from April to October. Average annual precipitation is 831 mm with 65% as rain coming from May to October, and mean annual temperature is 15°C with average daily minimum of -4.3°C in January and average daily maximum of 34°C in August.

RESULTS

Variation in vegetation between treatments and among patches within the Patch Burn pastures reflected different stages of recovery as a function of TSB (Table 1). Within Patch Burn pastures, forb cover peaked in current burned patches and in transitional patches whereas current burned patches contained about 20 times more bare ground than Traditional pastures (Table 1). Litter cover varied by almost a factor of four between current burned patches in Patch Burn pastures and Traditional pastures,

DISCUSSION

Consistent with the fire–grazing interaction model (Fuhlendorf and Engle 2001) and verifying the prediction we hypothesized, invertebrate community composition and invertebrate mass were sensitive to habitat heterogeneity provided by patch burning. As compared to the Traditional pastures, patches within Patch Burn pastures differed in invertebrate mass and the compositional contributions by various orders of invertebrates on the basis of time since burning and focal grazing. The response of

MANAGEMENT IMPLICATIONS

The shifting mosaic created by the Patch Burn treatment provides habitat that meets requirements for a broad range of invertebrate species. Allowing 2 yr for recovery from fire, patch burning is compatible with conservation of invertebrate biodiversity of rangeland, and therefore presents a potentially useful tool for managing prairie with fire and grazing to achieve an array of management objectives (e.g., sustainable livestock grazing enterprises, controlling woody plant invasion, and

ACKNOWLEDGMENTS

We thank John Wier, Timothy Tunnell, Chris Stansberry, and Chad Cummings for contributing to treatment application and for collecting vegetation data. Don Arnold's help with identification of invertebrates made this work possible.

LITERATURE CITED (67)

  • CollinsS.L.

    Fire frequency and community heterogeneity in tallgrass prairie: a field experiment

    Ecology

    (1992)
  • CoppedgeB.R. et al.

    Landscape cover type and pattern dynamics in fragmented southern Great Plains grasslands, USA

    Landscape Ecology

    (2001)
  • CoppedgeB.R. et al.

    Effects of seasonal fire, bison grazing and climatic variation on tallgrass prairie vegetation

    Plant Ecology

    (1998)
  • CoppedgeB.R. et al.

    Bison grazing patterns on seasonally burned tallgrass prairie

    Journal of Range Management

    (1998)
  • CoppockD.L. et al.

    Alteration of bison and black-tailed prairie dog grazing interaction by prescribed burning

    Journal of Wildlife Management

    (1986)
  • DennisP. et al.

    Distribution and abundance of small insects and arachnids in relation to structural heterogeneity of grazed, indigenous grasslands

    Ecological Entomology

    (1998)
  • DuvallV.L. et al.

    Rotation burning: a forage management system of longleaf pine-bluestem ranges

    Journal of Range Management

    (1964)
  • EngleD.M. et al.

    Viewpoint: the response of central North American prairies to seasonal fire

    Journal of Range Management

    (2001)
  • EvansE.W.

    Fire as a natural disturbance to grasshopper assemblages of tallgrass prairie

    Oikos

    (1984)
  • EvansE.W. et al.

    The relations of phytophagous invertebrates and range plants

  • FayP.A.

    Insect diversity in two burned and grazed grasslands

    Environmental Entomology

    (2003)
  • FordeJ.D. et al.

    Grassland habitat management using prescribed burning in Wind Cave National Park, South Dakota

    Prairie Naturalist

    (1984)
  • FreckletonR.P.

    Editorial: the problems of prediction and scale in applied ecology: the example of fire as a management tool

    Journal of Applied Ecology

    (2004)
  • FuhlendorfS.D. et al.

    Restoring heterogeneity on rangelands: ecosystem management based on evolutionary grazing patterns

    BioScience

    (2001)
  • FuhlendorfS.D. et al.

    Application of the fire-grazing interaction to restore a shifting mosaic in tallgrass prairie

    Journal of Applied Ecology

    (2004)
  • FuhlendorfS.D. et al.

    Scaling effects of grazing in a semi-arid savanna

    Journal of Vegetation Science

    (1999)
  • GutheryF.S.

    Slack in the configuration of habitat patches for northern bobwhites

    Journal of Wildlife Management

    (1999)
  • HaddadN.M. et al.

    Contrasting effects of plant richness and composition on insect communities: a field experiment

    American Naturalist

    (2001)
  • HansenJ.H.

    Comparison of insects from burned and unburned areas after a range fire

    Great Basin Naturalist

    (1986)
  • HobbsR.J. et al.

    Fire and grazing in the tallgrass prairie: contingent effects on nitrogen budgets

    Ecology

    (1991)
  • HutchinsonK.J. et al.

    The effects of sheep stocking level on invertebrate abundance, biomass and energy utilization in a temperate, sown grassland

    Journal of Applied Ecology

    (1980)
  • JoernA.

    Variation in grasshopper (Acrididae) densities in response to fire frequency and bison grazing in tallgrass prairie

    Environmental Entomology

    (2004)
  • JoernA.

    Disturbance by fire frequency and bison grazing modulate grasshopper assemblages in tallgrass prairie

    Ecology

    (2005)
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      For example, avian species diversity and richness of grassland-obligate birds are often greater in patch-burned and grazed areas compared with areas with traditional management strategies (Fuhlendorf et al., 2006; Coppedge et al., 2008; Powell, 2008; Holcomb et al., 2014; Hovick et al., 2014). Grassland heterogeneity also tends to favor aboveground invertebrates, as richness and overall abundance are greater on patch-burn and grazed areas than communities associated with standard grassland management (Engle et al., 2008; Doxon et al., 2011). Given that patch-burning and grazing can increase landscape heterogeneity both in composition and structure, this method could be used in areas dominated by non-native grasses to 1) increase factors that are limiting bobwhites such as bare ground, forbs, and subshrubs; and 2) provide heterogeneous patches where access to different habitat attributes is provided.

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    This research was funded by the Oklahoma Agricultural Experiment Station through project S-1822 and USDA-NRI Managed Ecosystems Program (02-00777). This article is published with the approval of the Director, Oklahoma Agricultural Experiment Station.

    At the time of the research, the senior author was Regents Professor, Dept of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK, USA.

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