Quantifying Relationships Between Bird And Butterfly Community Shifts And Environmental Change.

Quantifying the manner in which ecological communities respond during a time of decreasing precipitation is a first step in understanding how they will respond to longer-term climate change. Here we coupled analysis of interannual variability in remotely sensed data with analyses of bird and butterfly community changes in montane meadow communities of the Greater Yellowstone Ecosystem. Landsat satellite imagery was used to classify these meadows into six types along a hydrological gradient. The northern portion of the ecosystem, or Gallatin region, has smaller mean patch sizes separated by ridges of mountains, whereas the southern portion of the ecosystem, or Teton region, has much larger patches within the Jackson Hole valley. Both support a similar suite of butterfly and bird species. The Gallatin region showed more overall among-year variation in the normalized difference vegetation index (NDVI) when meadow types were pooled within regions, perhaps because the patch sizes are smaller on average. Bird and butterfly communities showed significant relationships relative to meadow type and NDVI. We identified several key species that are tightly associated with specific meadow types along the hydrological gradient. Comparing taxonomic groups, fewer birds showed specific habitat affinities than butterflies, perhaps because birds are responding to differences in habitat structure among meadow types and using the landscape at a coarser scale than the butterflies. Comparing regions, the Teton region showed higher predictability of community assemblages as compared to the Gallatin region. The Gallatin region exhibited more significant temporal trends with respect to butterflies. Butterfly communities in wet meadows showed a distinctive shift along the hydrological gradient during a drought period (1997–2000). These results imply that the larger Teton meadows will show more predictable (i.e., static) species–habitat associations over the long term, but that the smaller Gallatin meadows may be an area that will exhibit the effects of global climate change fasterSincere thanks go out to the University of Wyoming, National Park Service Research Center (AMK Ranch: Henry Harlow, director) for funding and accommodating our research team over the years. We also thank Brian Miller of the Denver Zoological Foundation for funding, collaboration, and general camaraderie. Data collection during 1997–2000 was funded by a grant from the Environmental Protection Agency (EPA) through their Ecological Assessment and Restoration program. Although funded by the EPA (through grant 96-NCERQA-1A to Debinski et al.), it has not been subjected to the Agency’s peer review and therefore does not necessarily reflect the views of the Agency and no official endorsement should be inferred. Additional funding was provided by the Iowa Space Grant Consortium and the Grand Teton Natural History Association. Statistical consulting was provided by Kirk Moloney and Philip Dixon of Iowa State University. This manuscript was improved by the recommendations of M. Turner, C. Boggs, E. Fleishman, and two anonymous reviewers. Finally, thanks to the many field technicians who have helped over the years, especially Amanda Hetrick and Julie Perret

Evaluating the Utility of Species Distribution Models in Informing Climate Change-Resilient Grassland Restoration Strategy

Tallgrass prairie ecosystems in North America are heavily degraded and require effective restoration strategies if prairie specialist taxa are to be preserved. One common management tool used to restore grassland is the application of a seed-mix of native prairie plant species. While this technique is effective in the short-term, it is critical that species' resilience to changing climate be evaluated when designing these mixes. By utilizing species distribution models (SDMs), species' bioclimatic envelopes–and thus the geographic area suitable for them–can be quantified and predicted under various future climate regimes, and current seed-mixes may be modified to include more climate resilient species or exclude more affected species. We evaluated climate response on plant functional groups to examine the generalizability of climate response among species of particular functional groups. We selected 14 prairie species representing the functional groups of cool-season and warm-season grasses, forbs, and legumes and we modeled their responses under both a moderate and more extreme predicted future. Our functional group “composite maps” show that warm-season grasses, forbs, and legumes responded similarly to other species within their functional group, while cool-season grasses showed less inter-species concordance. The value of functional group as a rough method for evaluating climate-resilience is therefore supported, but candidate cool-season grass species will require more individualized attention. This result suggests that seed-mix designers may be able to use species with more occurrence records to generate functional group-level predictions to assess the climate response of species for which there are prohibitively few occurrence records for modeling

Montane meadow change during drought varies with background hydrologic regime and plant functional group

Climate change models for many ecosystems predict more extreme climatic events in the future, including exacerbated drought conditions. Here we assess the effects of drought by quantifying temporal variation in community composition of a complex montane meadow landscape characterized by a hydrological gradient. The meadows occur in two regions of the Greater Yellowstone Ecosystem (Gallatin and Teton) and were classified into six categories (M1–M6, designating hydric to xeric) based upon Satellite pour l’Observation de la Terre (SPOT) satellite imagery. Both regions have similar plant communities, but patch sizes of meadows are much smaller in the Gallatin region. We measured changes in the percent cover of bare ground and plants by species and functional groups during five years between 1997 and 2007. We hypothesized that drought effects would not be manifested evenly across the hydrological gradient, but rather would be observed as hotspots of change in some areas and minimally evident in others. We also expected varying responses by plant functional groups (forbs vs. woody plants). Forbs, which typically use water from relatively shallow soils compared to woody plants, were expected to decrease in cover in mesic meadows, but increase in hydric meadows. Woody plants, such as Artemisia, were expected to increase, especially in mesic meadows. We identified several important trends in our meadow plant communities during this period of drought: (1) bare ground increased significantly in xeric meadows of both regions (Gallatin M6 and Teton M5) and in mesic (M3) meadows of the Teton, (2) forbs decreased significantly in the mesic and xeric meadows in both regions, (3) forbs increased in hydric (M1) meadows of the Gallatin region, and (4) woody species showed increases in M2 and M5 meadows of the Teton region and in M3 meadows of the Gallatin region. The woody response was dominated by changes in Artemisia spp. and Chrysothamnus viscidiflorus. Thus, our results supported our expectations that community change was not uniform across the landscape, but instead could be predicted based upon functional group responses to the spatial and temporal patterns of water availability, which are largely a function of plant water use and the hydrological gradient.This material is based upon research supported by the National Science Foundation under Grants 0518150 and EPS0814387, the Environmental Protection Agency under STAR Grant R825155, the University of Wyoming National Park Service Research Station, and the Grand Teton Natural History Association. We thank the University of Wyoming National Park Service Research Station (particularly Henry Harlow and Sue Consolo-Murphy) and the U.S. Forest Service for providing support and housing. Philip Dixon provided statistical consulting, and Mark Jakubauskas collaborated in setting up our initial field campaigns. Edward Cook assisted in selection and assessment of PDSI data; and Lisa Graumlich, Andy Bunn, Steve Gray, and Jeremy Littel advised us on climate reconstruction options for the GYE. Scott Creel, Sue Fairbanks, and Matt Kaufmann provided information on elk population trends in the region. Jill Sherwood designed the map. William Clark and two anonomous reviewers provided important suggestions that helped improve the manuscript. Finally, we thank the many research technicians and field assistants who helped in the fieldwork

Effects of fire and grazing on grasshopper sparrow nest survival

ABSTRACT Patch-burn grazing is a management framework designed to promote heterogeneity in grasslands, creating more diverse grassland structure to accommodate the habitat requirements of many grassland species, particularly grassland birds. Published studies on the effects of patch-burn grazing on passerines have been conducted on relatively large (430-980 ha pastures), contiguous grasslands, and only 1 of these studies has investigated the reproductive success of grassland birds. We assessed the effects of the patch-burn grazing and a more traditional treatment on the nesting ecology of grasshopper sparrows (Ammodramus savannarum) in small (<37 ha pastures) grasslands located in southern Iowa from May to August of 2008 and 2009. The study pastures were grazed from May to September and prescribed burns were conducted in the spring. We investigated the effects of treatments on clutch size and modeled grasshopper sparrow nest survival as a function of multiple biological and ecological factors. We found no difference in clutch size between treatments; however, we did find a reduction in clutch size for nests that were parasitized by brown-headed cowbirds (Molothrus ater). Constant daily survival rates were greater in patch-burn grazed pastures than in grazed-and-burned pastures (patch-burn grazed rate x ¼ 0:930 and grazed-and-burned rate x ¼ 0:907). Competitive survival models included year, stage of nest, nest age, and cool-season grass (csg) abundance within 5 m of the nest. Overall, csg abundance had the greatest effect on survival and had a negative influence. Although survival rates were highest in patch-burn grazed pastures, multiple factors influenced grasshopper sparrow survival. Nest survival rates for both treatments were relatively low, and variables other than treatment were more instrumental in predicting grasshopper sparrow survival. We recommend decreasing overall vegetation cover if increasing nesting habitat for grasshopper sparrows is a management goal. In addition, we recommend further investigation of heterogeneity management in fragmented landscapes to better understand how it affects biodiversity in relatively small management units that typify grassland habitats in the Midwest. ß 2011 The Wildlife Society

Bees and Butterflies in Roadside Habitats: Identifying Patterns, Protecting Monarchs, and Informing Management

Pollinating insects provide vital ecosystem services and are facing global declines and habitat loss. Roadsides are increasingly regarded as important potential areas for enhancing pollinator habitat. Understanding which roadsides best support pollinators\u2014and why\u2014is essential to helping locate and prioritize pollinator conservation efforts across roadside networks. To support this effort, we assessed butterfly, bee, and flowering plant species richness and abundance on a set of 63 stratified randomized roadside transects in State-managed rights-of-way in SE Idaho. Our research evaluated pollinator diversity as a function of highway class (interstate, U.S., and state highways), remotely sensed NDVI values (a measure of vegetation greenness), and floral resources. We found that smaller highways and lower (less green) maximum NDVI values were associated with significantly more bee species and total bees. Roadsides bordering sagebrush habitats typically had low NDVI values and higher bee and butterfly species richness, potentially contributing to this observed pattern. Butterfly richness increased in association with higher floral abundance in roadsides. Additionally, we identified and mapped 1,363 roadside patches of milkweed (Asclepias speciosa), larval host plant for the imperiled monarch butterfly (Danaus plexippus), in a survey of over 900 miles of southern Idaho highways. Based on these results and a literature review, we recommend management strategies to promote the health of pollinator populations in Idaho\u2019s rights-of-way and provide data to help ITD prioritize areas for pollinator-friendly management practices and habitat restoration within their highway system

Nature reserves as catalysts for landscape change

Scientists have called repeatedly for a broader conservation agenda that emphasizes not only protected areas but also the landscapes in which those areas are embedded. We describe key advances in the science and practice of engaging private landowners in biodiversity conservation and propose a conceptual model for integrating conservation management on reserves and privately owned lands. The overall goal of our model is to blur the distinction between land management on reserves and the surrounding landscapes in a way that fosters widespread implementation of conservation practices. Reserves assume a new role as natural laboratories where alternative land-use practices, designed to achieve conservation objectives, can be explored. We articulate the details of the model using a case study from the North American tallgrass prairie ecoregion.Peer reviewedNatural Resource Ecology and Managemen