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Grassland birds

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Bird Friendly Beef: Exploring The Impacts Of Regenerative Forage Production, B. Rigley, J. Gilley, Aem Johnson Feb 2024

Bird Friendly Beef: Exploring The Impacts Of Regenerative Forage Production, B. Rigley, J. Gilley, Aem Johnson

IGC Proceedings (1997-2023)

In the eastern US, managed hayfields and pasturelands represent a significant portion of remaining available grassland bird habitat, hosting several declining species including the eastern meadowlark (Sturnella magna) and the grasshopper sparrow (Ammodramus savannarum). However, these working landscapes have deteriorated in their ability to support grassland birds in recent decades due to more frequent and early hay cuttings and intensive grazing. Since the conservation of grassland birds is inextricably linked to agricultural systems, for conservation to be effective, land management must aim to benefit both producers and birds. Regenerative agriculture is an emerging approach that incorporates …


The Effects Of Native Perennial Cover On Physiological Indicators Of Habitat Quality For Sparrows In California Coastal Prairie Rangelands, Madeleine A. Ybarra Jan 2024

The Effects Of Native Perennial Cover On Physiological Indicators Of Habitat Quality For Sparrows In California Coastal Prairie Rangelands, Madeleine A. Ybarra

Cal Poly Humboldt theses and projects

Prescribed grazing management can have myriad effects on wildlife, with low to moderate grazing being associated with an increased abundance of some grassland birds. Specifically, Grasshopper Sparrow (Ammodramus savannarum) and Savannah Sparrow (Passerculus sandwichensis) abundance have been shown to be positively associated with both grazing and a higher percentage of native plant cover. However, measures of abundance provide an incomplete assessment of habitat quality for birds. Physiological and morphological measurements can help indicate environmental stress in individual birds, which reveals more information about habitat quality. We measured body condition and heterophil:lymphocyte ratios to gauge avian stress …


Avian Diversity, Abundance, And Nest Success Among Managed Prairies And Agricultural Plots In Oklahoma And Texas, Phillip J. Leonard, Douglas R. Wood, Wayne E. Meyer Dec 2017

Avian Diversity, Abundance, And Nest Success Among Managed Prairies And Agricultural Plots In Oklahoma And Texas, Phillip J. Leonard, Douglas R. Wood, Wayne E. Meyer

The Prairie Naturalist

Over the last 50 years, grassland birds experienced rapid declines due to habitat loss and degradation as a result of agricultural practices. Our objective was to document the diversity, abundance, and nest success of bird communities using managed prairie and agricultural plots at the Tishomingo National Wildlife Refuge (NWR) in southern Oklahoma and Hagerman NWR in northern Texas. From April 1 to July 15, 2013–2014, point count surveys, nest searches, nest monitoring, and vegetation sampling were conducted among three habitat treatments: managed prairie, unharvested wheat, and fallow agricultural plots. Species richness values for potential nesting species were higher in managed …


Strategic Habitat Conservation For Declining Grassland Wildlife Populations In The Oaks And Prairies Joint Venture, James Giocomo, Johnathan Hayes, Kenneth Gee, Jeff Raasch, Robert Perez Nov 2017

Strategic Habitat Conservation For Declining Grassland Wildlife Populations In The Oaks And Prairies Joint Venture, James Giocomo, Johnathan Hayes, Kenneth Gee, Jeff Raasch, Robert Perez

National Quail Symposium Proceedings

Degradation and conversion of functioning grassland ecosystems in North America has driven significant declines in grassland wildlife populations across multiple taxa. In an effort to address declines in the grasslands of Oklahoma and Texas, a number of governmental agencies and Non-Governmental Organizations have partnered to form the Oaks and Prairies Joint Venture (OPJV) to more strategically and collaboratively deliver conservation actions in this region. With northern bobwhite (Colinus virginianus) as the flagship species, OPJV has worked to implement a fully integrated Strategic Habitat Conservation framework that works at multiple scales to conduct biological planning, landscape conservation design, habitat …


Ecological Determinants Of Avian Productivity And Aviation Risk In Semi-Natural Grasslands, Tara Jenise Conkling May 2016

Ecological Determinants Of Avian Productivity And Aviation Risk In Semi-Natural Grasslands, Tara Jenise Conkling

Theses and Dissertations

Growing concerns about climate change, foreign oil dependency, and environmental quality have fostered interest in perennial native grasses (e.g. switchgrass [Panicum virgatum]) for bioenergy production while also maintaining biodiversity and ecosystem function. However, biofuel cultivation in marginal landscapes such as airport grasslands may have detrimental effects on aviation safety as well as demography and conservation efforts for grassland birds including Dickcissels (Spiza americana). In 2011–2013 I studied the response of avian populations to vegetation composition and harvest frequency of switchgrass monocultures and native warm-season grass (NWSG) mixtures at B. Bryan farms in Clay Co. MS, USA. Four treatments incorporating switchgrass …


Predicted Avian Responses To Bioenergy Development Scenarios In An Intensive Agricultural Landscape, Daniel R. Uden, Craig R. Allen, Rob B. Mitchell, Tim D. Mccoy, Qingfeng Guan Jan 2014

Predicted Avian Responses To Bioenergy Development Scenarios In An Intensive Agricultural Landscape, Daniel R. Uden, Craig R. Allen, Rob B. Mitchell, Tim D. Mccoy, Qingfeng Guan

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Conversion of native prairie to agriculture has increased food and bioenergy production but decreased wildlife habitat. However, enrollment of highly erodible cropland in conservation programs has compensated for some grassland loss. In the future, climate change and production of second-generation perennial biofuel crops could further transform agricultural landscapes and increase or decrease grassland area. Switchgrass (Panicum virgatum) is an alternative biofuel feedstock that may be economically and environmentally superior to maize (Zea mays) grain for ethanol production on marginally productive lands. Switchgrass could benefit farmers economically and increase grassland area, but there is uncertainty as to how conversions between rowcrops, …


Use Of Seeded Exotic Grasslands By Wintering Birds, Andrew D. George, Timothy J. O'Connell, Karen R. Hickman, David M. Lesliee Jr. Dec 2013

Use Of Seeded Exotic Grasslands By Wintering Birds, Andrew D. George, Timothy J. O'Connell, Karen R. Hickman, David M. Lesliee Jr.

The Prairie Naturalist

Despite widespread population declines of North American grassland birds, effects of anthropogenic disturbance on wintering habitat of this guild remain poorly understood. We compared avian abundance and habitat structure in fields planted to the exotic grass Old World bluestem (Bothriochloa ischaemum; OWB) to that in native mixed-grass prairie. During winters of 2007–2008 and 2008–2009, we conducted bird and vegetation surveys in six native grass and six OWB fields in Garfield, Grant, and Alfalfa counties, Oklahoma. We recorded 24 species of wintering birds in native fields and 14 species in OWB monocultures. While vegetation structure was similar between field …


Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper Oct 2012

Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper

Great Plains Research: A Journal of Natural and Social Sciences

Many species of grassland birds are area sensitive, which may exacerbate the ecological effects of the extensive loss and fragmentation of grasslands that has taken place across the northern Great Plains. However, the reasons for this area sensitivity are unclear, as vegetation structure, matrix composition, and restriction of movements among patches do not seem to provide viable explanations for species native to grasslands. Con specific attraction, whereby species are behaviorally stimulated to select habitat or establish territories near individuals of the same species, may help explain this area sensitivity. We review and discuss theoretical and empirical research on avian conspecific …


Avian Habitat Response To Grazing, Haying, And Biofuels Production In Native Warm-Season Forages In The Mid-South, Jessie Lee Birckhead Aug 2012

Avian Habitat Response To Grazing, Haying, And Biofuels Production In Native Warm-Season Forages In The Mid-South, Jessie Lee Birckhead

Masters Theses

Declines in grassland birds have been attributed to loss of habitat, habitat degradation, and changes in land management. In the Mid-South, pasture and hayfield management has focused on maintaining dense stands of non-native forages that do not provide suitable vegetative structure for grassland birds or northern bobwhite. Native warm-season grasses have been promoted for livestock forage and biofuels feedstock. However, little information exists on how these practices affect habitat for grassland songbirds or northern bobwhite in the Mid-South. We conducted a study of two cattle grazing treatments, two hay harvest treatments and a biofuels harvest treatment on vegetative structure for …


Agricultural Landuse Change Impacts On Bioenergy Production, Avifauna, And Water Use In Nebraska's Rainwater Basin, Daniel R. Uden Jul 2012

Agricultural Landuse Change Impacts On Bioenergy Production, Avifauna, And Water Use In Nebraska's Rainwater Basin, Daniel R. Uden

School of Natural Resources: Dissertations, Theses, and Student Research

Agriculture is an economically important form of landuse in the North American Great Plains. Since 19th Century European settlement, conversion of grasslands to rowcrops has increased food and bioenergy production, but has decreased wildlife habitat. Future agricultural landuse changes may be driven by alternative energy demands and regional climatic changes. Landuse change and its drivers could affect bioenergy production, wildlife populations and natural resources, and considering the potential impacts of impending changes in advance could assist with preparations for an uncertain future.

This study addressed how the conversion of marginally productive agricultural lands in the Rainwater Basin region of …


Multi-Scale Response Of Upland Birds To Targeted Agricultural Conservation, Kristine Oswald Evans May 2012

Multi-Scale Response Of Upland Birds To Targeted Agricultural Conservation, Kristine Oswald Evans

Theses and Dissertations

As human populations rise exponentially, agricultural production systems must be adapted to sustain ecosystem function. Government administered agricultural conservation programs may actualize greater gains in ecosystem services, including wildlife population gains, if conservation practices designed to target specific environmental outcomes are implemented strategically in agricultural landscapes. I evaluated multi-scale, multi-species, and multi-season avian population responses to a targeted native herbaceous buffer practice (CP33: Habitat Buffers for Upland Birds) under the continuous sign-up Conservation Reserve Program administered by the U.S. Department of Agriculture. CP33 is the first conservation practice targeted directly to support habitat and population recovery objectives of a national …


Identification Of Sprague's Pipit Nest Predators, Stephen K. Davis, Stephanie L. Jones, Kimberly Dohms, Teslin Holmes Jan 2012

Identification Of Sprague's Pipit Nest Predators, Stephen K. Davis, Stephanie L. Jones, Kimberly Dohms, Teslin Holmes

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Nest predation is the primary factor influencing grassland songbird reproductive success. Understanding factors driving spatial and temporal variation in nest survival requires that we identify the primary nest predators and factors influencing predator abundance and behavior. Predation events are rarely witnessed, and the identification of nest predators is inferred, often incorrectly, from nest remains or observations of potential predators. We used video photography to identify predators of Sprague's Pipit (Anthus spragueii) nests in Saskatchewan and Montana. We monitored 60 nests in Saskatchewan and 11 nests in Montana and documented at least ten different species preying upon eggs and …


Nest Defense- Grassland Bird Responses To Snakes, Kevin Ellison, Christine Ribic Jan 2012

Nest Defense- Grassland Bird Responses To Snakes, Kevin Ellison, Christine Ribic

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Predation is the primary source of nest mortality for most passerines; thus, behaviors to reduce the impacts of predation are frequently quantified to study learning, adaptation, and coevolution among predator and prey species. Video surveillance of nests has made it possible to examine real-time parental nest defense. During 1999-2009, we used video camera systems to monitor 518 nests of grassland birds. We reviewed video of 48 visits by snakes to 34 nests; 37 of these visits resulted in predation of active nests. When adult birds encountered snakes at the nest (n = 33 visits), 76% of the encounters resulted …


Bird Productivity And Nest Predation In Agricultural Grasslands, C.A. Ribic, Michael Guzy, Travis Anderson, David Sample, Jamie Nack Jan 2012

Bird Productivity And Nest Predation In Agricultural Grasslands, C.A. Ribic, Michael Guzy, Travis Anderson, David Sample, Jamie Nack

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Effective conservation strategies for grassland birds in agricultural landscapes require understanding how nesting success varies among different grassland habitats. A key component to this is identifying nest predators and how these predators vary by habitat. We quantified nesting activity of obligate grassland birds in three habitats [remnant prairie, cool-season grass Conservation Reserve Program (CRP) fields, and pastures) in southwest Wisconsin, 2002-2004. We determined nest predators using video cameras and examined predator activity using track stations. Bobolink (Dolichonyx oryzivorus) and Henslow's Sparrow (Ammodramus henslowii) nested primarily in CRP fields, and Grasshopper Sparrow (A. savannarum) in …


Avian Response To Production Stands Of Native Warm-Season Grasses In The Mid-South, Andrew Steven West Aug 2011

Avian Response To Production Stands Of Native Warm-Season Grasses In The Mid-South, Andrew Steven West

Masters Theses

Grassland birds have declined more than any other guild of birds in North America, largely due to loss and degradation of native grasslands. The Conservation Reserve Program (CRP) has restored some native warm-season grasses (NWSG), but grassland birds continued to decline (-1.1% annually) partly due to the limited acreage converted (1% of southeastern US). Using NWSG in production settings provides profit incentive to landowners while reducing dependency on government programs. Studies examining these production practices and their effect on grassland birds east of the Great Plains are limited. During 2009 – 2010, I surveyed 102 NWSG fields in Kentucky and …


Effects Of Prescribed Burning On Grassland Nesting Birds On Conservation Reserve Program Areas In Gove County, Kansas, Justin Vern Hamilton May 2011

Effects Of Prescribed Burning On Grassland Nesting Birds On Conservation Reserve Program Areas In Gove County, Kansas, Justin Vern Hamilton

Master's Theses

Great Plains grasslands were once one of the largest ecosystems in North America. However, farming, ranching, urban development, widespread fire suppression, and numerous other factors have created a great loss of this habitat in central North America. Organisms that depend on that habitat, such as grassland nesting birds, also have declined. The Conservation Reserve Program (CRP), which was established in 1985, paid landowners to remove land with highly erodible soils from production and plant it with perennial vegetation. Increases in CRP acreages brought about increases in numbers of several bird species that were in decline before the program existed. Prescribed …


Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz Jan 2010

Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz

Faculty Publications

The Conservation Reserve Program (CRP) is a voluntary cropland set-aside program where environmentally-sensitive cropland is retired to a conservation practice. Grassland birds should benefit because most CRP is grass habitat and because amount of land in CRP is highest in agriculture-dominated areas of the United States where grassland habitat has been most impacted. We used the Breeding Bird Survey and Common Land Unit (CLU) data (spatially-explicit data of farm field boundaries and land cover) to identify relations between types and configurations of CRP and grassland bird abundance in 3 Midwestern states. All 13 species we studied were related to at …


Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds, Kristel K. Bakker, Kenneth F. Higgins Jan 2009

Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds, Kristel K. Bakker, Kenneth F. Higgins

Natural Resource Management Faculty Publications

Little is known about how avian relationships to tracts of native sod prairie compare with avian relationships to single and multiple species of cool- and warm-season grassland plantings. We compared grassland bird species richness and density in 5 grassland cover types (n = 97) in the tallgrass prairie region of eastern South Dakota and western Minnesota, 2001–2004. Grassland bird species richness was significantly higher in native sod prairies than it was in all planted cover types except warm-season mixes. Grasslands dominated by exotic species did not support as many grassland bird species or have species densities as high as grasslands …


A Landscape Approach To Grassland Bird Conservation In The Prairie Pothole Region Of The Northern Great Plains, Frank Royce Quamen Jan 2008

A Landscape Approach To Grassland Bird Conservation In The Prairie Pothole Region Of The Northern Great Plains, Frank Royce Quamen

Graduate Student Theses, Dissertations, & Professional Papers

Prairie is one of the most imperiled ecosystems, and grassland birds have experienced steeper and more consistent declines than any other group of birds in North America. Habitat-based planning tools are a cornerstone of conservation in forested ecosystems, but remain a novel approach in grasslands. In Chapter 2, I develop spatially-explicit habitat models as decision support tools for conservation. I survey birds, measure local vegetation and quantify landscape features at 952 sites in western Minnesota and northwest Iowa. Findings indicate that cropland provides little habitat for grassland songbirds and that hayland does not compensate for loss of grasslands. Multiscale models …


Us Department Of Agriculture, Wildlife Services, National Wildlife Research Center, Brian E. Washburn, Thomas W. Seamans May 2007

Us Department Of Agriculture, Wildlife Services, National Wildlife Research Center, Brian E. Washburn, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

Herbaceous vegetation comprises the main habitat type in cool-seasons grasslands and can be managed by various methods. We compared changes in plant communities and bird and mammal use of grasslands that were not managed, managed by mechanical methods (mowing), or managed by chemical methods (plant growth regulator). This 1-year study was conducted from May through October 2003 in Erie County, Ohio. Twelve circular 1.5 ha plots were established: 4 were not managed, 4 were mowed to maintain vegetation height between 9–15 cm, and 4 were sprayed with a plant growth regulator and mowed when vegetation exceeded 15 cm. We monitored …


Grassland Birds In Restored Grassland Of The Rainwater Basin Region In Nebraska, Jill Sporrong Utrup, Craig A. Davis Jan 2007

Grassland Birds In Restored Grassland Of The Rainwater Basin Region In Nebraska, Jill Sporrong Utrup, Craig A. Davis

Great Plains Research: A Journal of Natural and Social Sciences

Conservationists and managers mention grassland restorations as a conservation strategy to reverse the decline of grassland bird populations in the Great Plains. In the Rainwater Basin Region of southcentral Nebraska, state and federal resource agencies have used grassland restorations to protect wetlands from sedimentation and agrichemical runoff. These grassland restorations may also provide important habitat for breeding grassland birds. In this paper, we describe the abundance, composition, nesting success, and habitat requirements of breeding birds in grassland restorations in the Rainwater Basin Region. We observed 14 grassland bird species in 12 grassland restorations. The most abundant species were dickcissels ( …


Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen Mar 2006

Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen

The Prairie Naturalist

We conducted a two-year survey of breeding birds in the Sheyenne National Grassland, North Dakota, to estimate total populations of breeding birds. The Grassland is of interest because it provides wildlife habitat and recreational birding opportunities. Indicated breeding pairs were counted on 100-m wide belt transects during morning surveys from late May to early July in 2002 and 2003. We surveyed approximately 6 to 7% of the Grassland each year. The most abundant species in both years were grasshopper sparrow (Ammodramus savannarum), red-winged blackbird (Agelaius phoeniceus), claycolored sparrow (Spizella pallida), Savannah sparrow (Passerculus …


Changes In Land Cover And Breeding Bird Populations With Restoration Of Riparian Habitats In East-Central Iowa, Thomas J. Benson, James J. Dinsmore, William L. Hohman Jan 2006

Changes In Land Cover And Breeding Bird Populations With Restoration Of Riparian Habitats In East-Central Iowa, Thomas J. Benson, James J. Dinsmore, William L. Hohman

Journal of the Iowa Academy of Science: JIAS

Conversion of Midwestern riparian areas for agricultural production has greatly altered their function and suitability for birds and other wildlife. Recently, however, restoration of riparian functions has been a major focus of land management agencies in the Midwest. We used historic land-use data to describe land-cover changes since European settlement and the subsequent effects of habitat restoration efforts on the landscape along a section of the Iowa River in east-central Iowa. We then used bird-density data collected in a subset of the study area in 2001 and 2002 to estimate changes in breeding bird populations of the entire study area …


Proximate And Landscape Factors Influence Grassland Bird Distributions, Mary Ann Cunningham, Douglas H. Johnson Jan 2006

Proximate And Landscape Factors Influence Grassland Bird Distributions, Mary Ann Cunningham, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled …


Influences Of Management Regimes On Breeding Bird Densities And Habitat In Mixed-Grass Prairie: An Example From North Dakota, Andrea A. Lueders, Patricia L. Kennedy, Douglas H. Johnson Jan 2006

Influences Of Management Regimes On Breeding Bird Densities And Habitat In Mixed-Grass Prairie: An Example From North Dakota, Andrea A. Lueders, Patricia L. Kennedy, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

It is well known that North American grassland bird populations appear to be declining (Igl and Johnson 1997, Sauer et al. 2004). Most of these birds breed and winter in North America, so declines are likely associated with continental processes (Knopf 1994). Scientists have also observed parallel declines among species that have overlapping breeding ranges but disparate wintering distributions (Igl and Johnson 1997). These patterns suggest declines may be linked to problems on the breeding grounds.


Avian Response To Meadow Restoration In The Central Great Plains, Rosalind B. Renfrew, Douglas H. Johnson, Gary R. Lingle, W. Douglas Robinson Jan 2006

Avian Response To Meadow Restoration In The Central Great Plains, Rosalind B. Renfrew, Douglas H. Johnson, Gary R. Lingle, W. Douglas Robinson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Native grassland is one of the most heavily degraded of all North American ecosystems, and restoration of altered grasslands is a tool used to mitigate some of the biological ramifications of past land use practices. Providing habitat for grassland-dependent bird species often is one of the many goals of restoration. We evaluated the efficacy of meadow restoration for breeding birds in the Nebraska Platte River Valley by comparing the bird community and vegetation structure on 25 natural (original sod) and 25 restored meadows. We conducted principal components analyses on the vegetation structure and on the bird community, and modeled the …


Grassland Bird Use Of Crp Fields That Differ By Age-Class And Cover Type, Kristel K. Bakker, Sarah L. Eggebo, Kenneth F. Higgins, David E. Naugle Jan 2004

Grassland Bird Use Of Crp Fields That Differ By Age-Class And Cover Type, Kristel K. Bakker, Sarah L. Eggebo, Kenneth F. Higgins, David E. Naugle

Proceedings of the North American Prairie Conferences

During the past 50 years increasing agricultural practices have transformed native habitats into row~crop fields, making the Conservation Reserve Program (CRP) grass lands important habitat for wildlife populations. Limited information exists on how nongame grassland bird species relate to different stand ages and cover types of Conservation Reserve Program. Conservation Reserve Program grassland study sites (n = 42) were stratified by stand age (old [10-13 years] and new [0-3 years] grasslands), and cover types (CPI-cool-season grasslands and CPZ-warm-season grasslands) in eastern South Dakota. Field age rather than cover type was more predictive of grassland bird occurrence and density. Sedge wrens …


Could The Area-Sensitivity Of Some Grassland Birds Be Affected By Landscape Composition?, David Joseph Horn, Rolf R. Koford Jan 2004

Could The Area-Sensitivity Of Some Grassland Birds Be Affected By Landscape Composition?, David Joseph Horn, Rolf R. Koford

Proceedings of the North American Prairie Conferences

Several grassland bird species have been shown to be area sensitive. This area sensitivity occurs when a species' frequency of occurrence, or relative abundance, tends to be lower in smaller fields. The detection of area sensitivity, however, is not consistent among studies because a species may exhibit area sensitivity in one study, but not in another. We tested the hypothesis that a species' area sensitivity varies depending on the amount of grassland in the landscape. The study took place in central North Dakota during the 1996 and 1997 breeding seasons on 46 fields enrolled in the Conservation Reserve Program (CRP). …


Guidelines For Finding Nests Of Passerine Birds In Tallgrass Prairie, Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson Jul 2003

Guidelines For Finding Nests Of Passerine Birds In Tallgrass Prairie, Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The productivity of birds is one of the most critical components of their natural history affected by habitat quality. Birds might occur at high densities in a given habitat patch but have low nesting success. Such "population sinks" would not be detected if observers relied solely on estimates of bird density. Therefore, it is essential to monitor nests and determine their outcomes. Although interest in grassland-nesting passerines has increased greatly during the last decade, we still know little about factors affecting their nesting success. To stimulate more research in this area, we summarize several methods for nest-searching and provide suggestions …


Effects Of Field Size And Landscape Composition On Grassland Birds In South-Central Iowa, David Joseph Horn, Rolf R. Koford, Malinda L. Braland Jan 2002

Effects Of Field Size And Landscape Composition On Grassland Birds In South-Central Iowa, David Joseph Horn, Rolf R. Koford, Malinda L. Braland

Journal of the Iowa Academy of Science: JIAS

Many species of grassland birds have been shown to avoid smaller fields. The avoidance of smaller fields, however, has not been consistently reported; avoidance may occur in one study, but not in another. To examine one possible reason for these inconsistencies, we examined how landscape composition influenced the relations between occurrence or abundance and field size. The study took place during the 1998 breeding season on 44 Conservation Reserve Program (CRP) fields located in Adair, Ringgold, and Union counties. The relations between occurrence, abundance, and field size were not influenced by landscape composition for any species.

Grasshopper Sparrow, Ammodramus savannarum, …