Passerine Use of Grasslands Managed With Two Grazing Regimes on the Missouri Coteau in North Dakota

Several rotational grazing systems have been implemented on the Missouri Coteau in central and northcentral North Dakota as part of the Prairie Pothole Joint Venture (PP N). The impacts these systems have on grassland passerines are not fully understood. Objectives for this study include determining relative abundance, species composition and reproductive success of passerines as well as vegetation characteristics for rotational and traditional season-long grazing regimes. Passerine relative abundance and species richness were determined on rotational grazing systems during 1995-1997 and on season-long grazed pastures during 1996-1997 using 122 fixed, 100 m radius, point counts. Relative abundance was assessed by recording singing males or breeding pairs heard or seen during each count. Twenty-five grassland species were recorded in 1995, 30 in 1996 and 29 in 1997. Grasshopper sparrows, brown-headed cowbirds, and clay-colored sparrows occurred most frequently on point counts. No differences occurred between grazing regimes for species richness or relative abundance in 1996. However, in 1997, rotational grazing systems had higher species relative abundance and species richness compared to the season-long grazed pastures. Savannah sparrow, grasshopper sparrow, western meadowlark, bobolink, and Baird's sparrow all have been previously cited as being negatively affected from grazing. These grassland birds were grouped into a grazing sensitive guild, which had a higher mean relative abundance on rotational grazing systems compared with season-long pastures in 1997, but was not significantly higher in 1996. Reproductive success by species was estimated on 6 randomly selected points for each study site in 1996 and 1997 using behavioral cues. Reproductive success estimates of bird species did not differ between grazing regimes for either year. A total of 18 vegetation characteristics were used to determine differences between grazing regimes. Forb cover and shrub density were greater (P<0.05) on season-long grazed pastures in 1996 but not in 1997. Average litter depth was higher on rotational grazing systems (P<0.05) in 1997, but was not significantly different in 1996. Prescribed rotational grazing systems implemented in the Chase Lake and Northern Coteau PPN project areas benefited landowner livestock operations without negatively impacting grassland passerines.

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis - Open Access

Discipline thesis:degree_discipline

Wildlife and Fisheries Science

Year

1998

Author dc:creator

• Schneider, Natoma A.

Contributors dc:contributor

• Kenneth F. Higgins

• grasslands
• grazing
• passerine
• missouri coteau
• north dakota
• Natural Resources and Conservation

Statement dc:rights

• Copyright © 1998 Natoma A. Schneider. All rights reserved.

Language dc:language

en

Repository record dc:identifier

https://openprairie.sdstate.edu/etd/393

OAI identifier oai:identifier

oai:openprairie.sdstate.edu:etd-1393