Area Requirements of Grassland Birds: A Regional Perspective

Abstract Area requirements of grassland birds have not been studied except in tallgrass prairie. We studied the relation between both species-occurrence and density and patch size by conducting 699 fixed-radius point counts of 15 bird species on 303 restored grassland areas in nine counties in four northern Great Plains states. Northern Harrier (Circus cyaneus), Sedge Wren (Cistothorus platensis), Clay-colored Sparrow (Spizella pallida), Grasshopper Sparrow (Ammodramus savannarum), Baird's Sparrow (Ammodramus bairdii), Le Conte's Sparrow (Ammodramus leconteii), and Bobolink (Dolichonyx oryzivorus) were shown to favor larger grassland patches in one or more counties. Evidence of area sensitivity was weak or ambivalent for Eastern Kingbird (Tyrannus tyrannus), Common Yellowthroat (Geothlypis trichas), Savannah Sparrow (Passerculus sandwichensis), and Western Meadowlark (Sturnella neglecta). Red-winged Blackbirds (Agelaius phoeniceus) preferred larger patches in some counties, and smaller patches in others. Mourning Doves (Zenaida macroura) and Brown- headed Cowbirds (Molothrus ater) tended to favor smaller grassland patches. Three species showed greater area sensitivity in counties where each species was more common. Five species demonstrated some spatial pattern of area sensitivity, either north to south or east to west. This study demonstrates the importance of replication in space; results from one area may not apply to others because of differences in study design, analytical methods, location relative to range of the species, and surrounding landscapes.

Download Full-text

Conservation of Grassland Birds in an Urbanizing Landscape: A Historical Perspective

The Condor ◽

10.1093/condor/104.3.643 ◽

2002 ◽

Vol 104 (3) ◽

pp. 643-651 ◽

Cited By ~ 2

Author(s):

Zach F. Jones ◽

Carl E. Bock

Keyword(s):

Great Plains ◽

Open Space ◽

Grassland Birds ◽

Athene Cunicularia ◽

Passerculus Sandwichensis ◽

Ammodramus Savannarum ◽

Dolichonyx Oryzivorus ◽

Lanius Ludovicianus ◽

Shortgrass Prairie ◽

Sturnella Neglecta

Abstract Landscape alterations resulting from urban expansion are among those factors negatively impacting Great Plains grassland birds. The City and County of Boulder, Colorado, manage one of the largest grassland open-space systems in North America, but it is embedded in an area of rapid urban growth. We compared bird count data from the 1980s and 1990s with checklist information about the Boulder grassland avifauna between 1900 and 1937, with the goal of determining what proportion and which species of the historical grassland avifauna are being sustained on Boulder open space. Of 29 native species present in 1900, 22 (76%) appeared on our counts in the 1990s. Formerly common species that disappeared or declined mostly were birds associated with shortgrass prairie, including Burrowing Owl (Athene cunicularia), Common Nighthawk (Chordeiles minor), Loggerhead Shrike (Lanius ludovicianus), and Lark Bunting (Calamospiza melanocorys). By contrast, species associated with mixed and tallgrass habitats increased or held steady, including Vesper Sparrow (Pooecetes gramineus), Savannah Sparrow (Passerculus sandwichensis), Grasshopper Sparrow (Ammodramus savannarum), Bobolink (Dolichonyx oryzivorus), and Western Meadowlark (Sturnella neglecta). We conclude that municipal open spaces can support populations of many Great Plains grassland birds, but that sustaining species associated with the shortgrass prairie may prove especially challenging. Conservación de Aves de Pastizal en un Paisaje de Crecimiento Urbano: Una Perspectiva Histórica Resumen. La alteración del paisaje causada por la expansión urbana es uno de los factores que impacta negativamente a las aves de los pastizales de los “Great Plains.” La ciudad y el condado de Boulder, Colorado, maneja uno de los sistemas de espacios abiertos de pastizal más grande de Norteamérica, el cual se encuentra rodeado por un área de crecimiento urbano. Comparamos datos de conteo de aves de los 1980s y 1990s con informacíon de la avifauna de Boulder entre 1900 y 1937, con el propósito de determinar qué proporción y cuántas especies de las aves de pastizal registradas históricamente se mantuvieron en los espacios abiertos de Boulder. De 29 especies nativas presentes en 1900, 22 (76%) aparecen en nuestros conteos de los 1990s. Especies anteriormente comunes pero que desaparecieron o disminuyeron en cantidad, fueron aves relacionadas principalmente con praderas de pasto corto, incluyendo Athene cunicularia, Chordeiles minor, Lanius ludovicianus y especialmente Calomospiza melanocorys. Por el contrario, especies asociadas a hábitats mixtos o de pasto alto han aumentado o se han mantenido, incluyendo Pooecetes gramineus, Passerculus sandwichensis, Ammodramus savannarum, Dolichonyx oryzivorus y Sturnella neglecta. Concluimos que los espacios abiertos municipales pueden sostener poblaciones de varias especies de aves de pastizal. Sin embargo, será más difícil mantener aquellas especies que prefieren praderas de pasto corto, porque las áreas continuas y amplias que necesitan, ya no existen.

Download Full-text

Developing spatial models to guide conservation of grassland birds in the U.S. Northern Great Plains

The Condor ◽

10.1650/condor-17-14.1 ◽

2017 ◽

Vol 119 (3) ◽

pp. 506-525 ◽

Cited By ~ 9

Author(s):

Neal D. Niemuth ◽

Michael E. Estey ◽

Sean P. Fields ◽

Brian Wangler ◽

Andy A. Bishop ◽

...

Keyword(s):

Great Plains ◽

Grassland Birds ◽

Spatial Models ◽

Northern Great Plains ◽

The U.S

Download Full-text

Effects of Prescribed Burns and Bison (Bos Bison) Grazing on Breeding Bird Abundances in Tallgrass Prairie

The Auk ◽

10.1093/auk/123.1.183 ◽

2006 ◽

Vol 123 (1) ◽

pp. 183-197 ◽

Cited By ~ 5

Author(s):

Alexis F. L A. Powell

Keyword(s):

Tallgrass Prairie ◽

Grassland Birds ◽

Bird Species ◽

Breeding Bird ◽

Data Set ◽

Prescribed Burns ◽

Grasshopper Sparrow ◽

Flint Hills ◽

Bos Bison ◽

Henslow's Sparrow

Abstract Grassland birds have declined more than any other avian assemblage in North America, with nearly every species showing negative population trends. In the Flint Hills of Kansas, the largest remnant of the tallgrass prairie biome, annual spring burning of rangeland has recently replaced burning every 2–3 years. I examined effects of different burning and bison (Bos bison) grazing regimes on June abundances of seven bird species using a 23-year data set from the Konza Prairie Biological Station. Fire significantly affected the abundances of six of the seven species. Effects varied among species but, notably, four grass-dependent species—Grasshopper Sparrow (Ammodramus savannarum), Henslow’s Sparrow (A. henslowii), Dickcissel (Spiza americana), and Eastern Meadowlark (Sturnella magna)— and the shrub-dependent Bell’s Vireo (Vireo bellii)—were least abundant or absent at sites in the breeding season immediately following burning. Upland Sandpipers (Bartramia longicauda) were most abundant at sites in the season following burning, whereas Brown-headed Cowbirds (Molothrus ater) exhibited no significant response. Bison grazing increased abundance of Upland Sandpiper and Grasshopper Sparrow, nearly eliminated Henslow’s Sparrow, and (in combination with recent fire) lowered the abundance of Dickcissel. Although fire and grazing are natural forces that maintain tallgrass prairie, their action was, until recently, intermittent and patchy, providing grassland birds with a variety of levels of disturbance. If the vast Flint Hills prairie is to serve as a grassland bird stronghold, the region-wide practice of annual burning with intensive grazing must be replaced with alternatives that restore heterogeneity to the landscape. Efectos de las Quemas Programadas y del Pastoreo de los Bisontes sobre la Abundancia de Aves Reproductivas en Praderas de Pasto Alto

Download Full-text

Edge Avoidance by Nesting Grassland Birds: A Futile Strategy in a Fragmented Landscape

The Auk ◽

10.1093/auk/122.2.618 ◽

2005 ◽

Vol 122 (2) ◽

pp. 618-636 ◽

Cited By ~ 5

Author(s):

Rosalind B. Renfrew ◽

Christine A. Ribic ◽

Jamie L. Nack

Keyword(s):

Nest Predation ◽

Bos Taurus ◽

Grassland Birds ◽

Nest Density ◽

Fragmented Landscape ◽

Spermophilus Tridecemlineatus ◽

Grassland Bird ◽

Passerculus Sandwichensis ◽

Dolichonyx Oryzivorus ◽

Vegetation Height

Abstract Some grassland passerine species are considered area-sensitive, but the mechanisms underlying that phenomenon are not understood, particularly on grazed grasslands. Area sensitivity may result from edge avoidance or higher nest predation near edges, both of which may be influenced by predator activity or cattle-induced vegetational differences between pasture edge and interior. We assessed the effect of distance to edge on nest density and predation Savannah Sparrows (Passerculus sandwichensis), Grasshopper Sparrows (Ammodramus savannarum), Bobolinks (Dolichonyx oryzivorus), and meadowlarks (Sturnella spp.) along wooded and nonwooded edges of Wisconsin pastures in 1998-2000 and the activity of potential mammalian nest predators along those edges in 2000-2001. We found a positive relationship between nest density and distance from edge for all edge types combined, but that was not the result of effects of wooded edges: we found no difference in density between nests located <50 or <100 m from wooded versus nonwooded (crop or grassland) edges. Models that included combinations of vegetation structure (e.g. concealment), initiation date, year, or edge variables (or all four) were poor predictors of the probability of nest predation. Placing nests away from edges, therefore, did not reduce the risk of nest predation. Eight species known to prey on grassland bird nests were documented along pasture edges, raccoon (Procyon lotor) being the most common. Frequency of raccoon and thirteen-lined ground squirrel (Spermophilus tridecemlineatus) visitation was higher along wooded edges and nonwooded edges, respectively. Cattle (Bos taurus) activity did not differentially affect vegetation height-density along edges compared with that in the pasture interior. Possible reasons for predation risk being similar in both pasture interiors and edges in a fragmented landscape include the ease with which predators can move within pastures, high percentage of resident grassland predators, and small size (median = 47.2 ha) of pastures.

Download Full-text

Geographic Variation in Brown-Headed Cowbird (Molothrus Ater) Parasitism on Dickcissels (Spiza Americana) in Great Plains Tallgrass Prairie

The Auk ◽

10.1093/auk/122.2.648 ◽

2005 ◽

Vol 122 (2) ◽

pp. 648-660 ◽

Cited By ~ 2

Author(s):

William E. Jensen ◽

Jack F. Cully

Keyword(s):

Geographic Variation ◽

Great Plains ◽

Tallgrass Prairie ◽

Brood Parasitism ◽

Molothrus Ater ◽

Grassland Birds ◽

Spiza Americana ◽

Flint Hills ◽

Cowbird Parasitism ◽

Study Sites

Abstract The incidence of brood parasitism by Brown-headed Cowbirds (Molothrus ater; hereafter “cowbirds“) within host species typically reflects the continental pattern in cowbird abundance across North America, where parasitism is heaviest in the Great Plains. However, we found considerable variation in cowbird parasitism on Dickcissel (Spiza americana) nests within a subregion of the Great Plains (the Flint Hills), where the highest levels of cowbird parasitism on grassland bird nests had been previously reported. Local parasitism frequencies on Dickcissel nests varied latitudinally across the Flint Hills, ranging from 0% to 92% of nests parasitized. Interestingly, we found no obvious patterns in habitat or host attributes that were associated with this steep geographic gradient in brood parasitism. Cowbird parasitism on Dickcissel nests was not correlated with the vertical density of local prairie vegetation, mean nest distance to edge, proportion of forest to grassland habitat surrounding study sites (≤5 to 10 km), geographic variation in host abundance, or Dickcissel density or nest initiation dates. Parasitism frequencies and intensities (number of cowbird eggs per parasitized nest) on Dickissel nests were only significantly related to variation in local female cowbird density. Dickcissel clutch size and apparent fledging success were negatively correlated with local cowbird parasitism levels. Geographic patterns in cowbird abundance within and among regions should be considered when establishing conservation areas for grassland birds or other cowbird hosts of concern.

Download Full-text

Inventory of Lowland-Breeding Birds on the Alaska Peninsula

Journal of Fish and Wildlife Management ◽

10.3996/082017-jfwm-070 ◽

2018 ◽

Vol 9 (2) ◽

pp. 637-658

Author(s):

Susan E. Savage ◽

T. Lee Tibbitts ◽

Kristin A. Sesser ◽

Robb A.S. Kaler

Keyword(s):

Survey Design ◽

Bird Species ◽

Common Species ◽

Habitat Associations ◽

Passerculus Sandwichensis ◽

Alaska Peninsula ◽

Point Counts ◽

Sandhill Crane ◽

Calcarius Lapponicus ◽

Tall Shrub

Abstract We conducted the first systematic inventory of birds in the lowlands (areas ≤100 m above sea level) of the Alaska Peninsula during summers of 2004–2007 to determine their breeding distributions and habitat associations in this remote region. Using a stratified random survey design, we allocated sample plots by elevation and land cover with a preference for wetland cover types used by shorebirds, a group of particular interest to land managers. We surveyed birds during 10-min counts at 792 points across 52, 5 km × 5 km sample plots distributed from south of the Naknek River (58.70°N,157.00°W) to north of Port Moller (56.00°N,160.52°W). We detected 95 bird species including 19 species of shorebirds and 34 species (36% of total) considered at the time to be of conservation concern for the land managers in the region. The most numerous shorebirds on point counts were dunlin Calidris alpina, short-billed dowitcher Limnodromus griseus, and Wilson's snipe Gallinago delicata. We found the breeding-season endemic marbled godwit Limosa fedoa beringiae at 20 plots within a 3,000-km2 area from north of Ugashik Bay to just north of Port Heiden and east to the headwaters of the Dog Salmon and Ugashik rivers. The most abundant passerines on point counts were American tree sparrow Spizelloides arborea, Lapland longspur Calcarius lapponicus, and savannah sparrow Passerculus sandwichensis. Sandhill crane Antigone canadensis, glaucous-winged gull Larus glaucescens, and greater scaup Aythya marila were also relatively abundant. We categorized habitat associations for 30 common species and found that lowland herbaceous vegetation supported wetland-focused species including sandhill crane, marbled godwit, short-billed dowitcher, and dunlin; whereas, dwarf shrub-ericaceous vegetation supported tundra-associated species such as willow ptarmigan Lagopus lagopus, rock sandpiper Calidris ptilocnemis, and American pipit Anthus rubescens. Tall shrub vegetation was important to several species of warblers and sparrows, as well as one species of shorebird (greater yellowlegs Tringa melanoleuca). We found that point counts augmented with incidental observations provided an almost complete inventory of lowland-breeding species on the study area. These data form a baseline to monitor any future changes in bird distribution and abundance on the Alaska Peninsula.

Download Full-text

Effects of habitat type on bird nesting in the desert grasslands of central Mexico: conservation implications

Oryx ◽

10.1017/s0030605310000426 ◽

2010 ◽

Vol 44 (3) ◽

pp. 448-454 ◽

Cited By ~ 1

Author(s):

César Posadas-Leal ◽

Leonardo Chapa-Vargas ◽

José Tulio Arredondo-Moreno ◽

Elisabeth Huber-Sannwald

Keyword(s):

Nest Survival ◽

Grassland Birds ◽

Habitat Type ◽

Bird Species ◽

Central Mexico ◽

Habitat Types ◽

Passerculus Sandwichensis ◽

Conservation Implications ◽

Study Sites ◽

Agricultural Areas

AbstractPopulations of North American grassland birds have suffered drastic declines. The causes of these declines are only partially understood and may vary among regions. During the 2004 and 2005 breeding seasons we recorded survival information from 220 nests of four bird species in nine study sites representing three habitat types of the desert grasslands of central Mexico, where grassland birds had not yet been studied. We predicted that land-use change from shortgrass steppe to heavily grazed savannah-type grasslands and agriculture would negatively affect nesting success, number of fledglings and nest abundance. We also examined temporal effects on reproductive success. We found some evidence that nest survival of savannah sparrows Passerculus sandwichensis, loggerhead shrikes Lanius ludovicianus and white-winged doves Zenaida asiatica varied with date, and that nest survival of the dove was lowest in agricultural sites. However, confidence intervals were large, suggesting that other variables were also important. Whereas white-winged dove nests were notably more abundant in agricultural areas compared to the other habitat types, western meadowlark Sturnella neglecta nests were not found in agricultural areas. Ploughing caused the largest proportion of nest failures in agricultural areas and, on average, all species fledged fewer young per nest in agricultural areas. Therefore, minimizing agriculture and adjusting harvest times could enhance conservation of grassland-nesting birds in central Mexico. Our study also suggests that inter-annual variation in rainfall can change the onset of nesting by at least 2 months.

Download Full-text

Quantifying specialist avifaunal decline in grassland birds of the Northern Great Plains

Ecosphere ◽

10.1002/ecs2.2523 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 5

Author(s):

Maureen D. Correll ◽

Erin H. Strasser ◽

Adam W. Green ◽

Arvind O. Panjabi

Keyword(s):

Great Plains ◽

Grassland Birds ◽

Northern Great Plains

Download Full-text

Trends in Bird Densities at a Remnant Fescue Grassland in Saskatchewan

The Canadian Field-Naturalist ◽

10.22621/cfn.v131i2.1904 ◽

2017 ◽

Vol 131 (2) ◽

pp. 170-178

Author(s):

Bohdan Pylypec

Keyword(s):

Grassland Birds ◽

Athene Cunicularia ◽

Passerculus Sandwichensis ◽

Burrowing Owl ◽

Dolichonyx Oryzivorus ◽

The Past ◽

Anthus Spragueii ◽

Horned Lark ◽

Sprague's Pipit ◽

The 1960S

Populations of grassland birds in North America have declined greatly in the past five decades. Hypothesized drivers of decline include habitat loss, fragmentation, and adverse impacts from human activities. At a remnant fescue grassland in Saskatoon, Saskatchewan numbers of Savannah Sparrow (Passerculus sandwichensis), Western Meadowlark (Sturnella neglecta), Brewer’s Blackbird (Euphagus cyanocephalus), and Vesper Sparrow (Pooecetes gramineus) have been stable. Numbers of clay-colored Sparrow (Spizella pallida) have increased since the 1960s. Sprague’s Pipit (Anthus spragueii), Upland Sandpiper (Bartramia longicauda), and Burrowing Owl (Athene cunicularia) are no longer present. Baird’s Sparrow (Ammodramus bairdii), Bobolink (Dolichonyx oryzivorus), and Horned Lark (Eremophila alpestris) have become irregular visitors. In the past 50 years, 91 species have been observed displaying territorial behaviour, feeding, nesting, or migrating at this remnant native grassland. With encroaching urban development and increased human influence at the prairie and surrounding area, the impacts on the bird communities at the site in the future are unknown.

Download Full-text

Bobolink (Dolichonyx oryzivorus) Declines Follow Bison (Bison bison) Reintroduction on Private Conservation Grasslands

Animals ◽

10.3390/ani11092661 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2661

Author(s):

Rachel H. Kaplan ◽

Kristen M. Rosamond ◽

Sandra Goded ◽

Alaaeldin Soultan ◽

Alex Glass ◽

...

Keyword(s):

Breeding Season ◽

Grassland Birds ◽

Bird Species ◽

Bison Bison ◽

Conservation Strategy ◽

Bird Conservation ◽

Dolichonyx Oryzivorus ◽

Breeding Populations ◽

Species Of Conservation Concern ◽

Bird Breeding

Among the most rapidly declining birds in continental North America, grassland birds evolved with American bison (Bison bison) until bison nearly became extinct due to overhunting. Bison populations have subsequently rebounded due to reintroductions on conservation lands, but the impacts of bison on grassland nesting birds remain largely unknown. We investigated how bison reintroduction, together with other land management and climate factors, affected breeding populations of a grassland bird species of conservation concern, the Bobolink (Dolichonyx oryzivorus). We quantified population changes in Bobolinks over an 18-year period in conservation grasslands where bison were reintroduced, compared with adjacent grasslands grazed by cattle and where hay was harvested after the bird breeding season. Four years after bison reintroduction, the bison population in the study area had doubled, while Bobolink abundance declined 62% and productivity declined 84%. Our findings suggest that bison reintroduction as a conservation strategy may be counterproductive in grassland fragments where overgrazing, trampling, and other negative impacts drive declines in grassland breeding birds. Where bird conservation is an objective, small grassland reserves may therefore be inappropriate sites for bison reintroduction. To maximize conservation benefits to birds, land managers should prioritize protecting grassland birds from disturbance during the bird breeding season.

Download Full-text