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Case studies of Sharp-tailed Grouse (Tympanuchus phasianellus) population dynamics before and during re-introduction of fire to northern mixed-grass prairies that lacked fire for multiple decades are unavailable. At a 108-km² northern mixedgrass prairie refuge in North Dakota, fire was suppressed from the early 1900s through late 1970s. Nine management units (total area 16.8 km², 15.7% of the refuge) received initial prescribed fire treatments during 1979-1984. The mean annual density of male Sharp-tailed Grouse attending leks on these units during 1981-1985 (9.0 males/km²) was twice that on the same units during 1961-1965 (4.2 males/km²), amid the fire exclusion era; nonoverlap of 90% CIs encompassing the means suggested a significant treatment effect. However, densities of males on units managed without prescribed fire during 1961-1965 and 1981-1985 did not change between the two periods. By 1987, fire had been re--introduced to >50% of the refuge overall. Mean annual abundance (i.e., total numbers) of lekking males on the entire refuge did not differ between 1961-1965 and 1981-1985 but was significantly greater during 1989-1993 than during 1961-1965 and 1981-1985. Changes in density and abundance of lekking males coincided with fire-induced reductions in woody cover and increases in herbaceous cover. Our study illustrates the marked capacity of Sharp-tailed Grouse to respond to reductions of tree and shrub cover resulting from prescribed fire in northern mixed-grass prairie and the species' attraction to habitat disturbance in general. [ABSTRACT FROM AUTHOR]

Presents a study that measured the reproductive success and nesting density of Cooper's hawks in the Souris River basin of north-central North Dakota during 1994 to 1996 and 1998 to 2000. Background on Cooper's hawk; Methodology; Differences in nest success of studied woodland types.

Presents a note on a study which examined the post-fledgling movement of juvenile Piping Plovers in North America's northern Great Plains. Factors influencing post-fledgling survival of plovers; Method used in observing plovers.

To more effectively manage remaining native grasslands and decliningpopulations of prairie passerine birds, linkages between disturbanceregimes, vegetation, and bird abundance need to be more fully understood. Therefore, we examined bird-habitat relationships on mixed-grass prairie at Lostwood National Wildlife Refuge (NWR) in northwestern North Dakota, where prescribed fire has been used as a habitat management tool since the 1970s. We sampled bird abundance on upland prairie at 310 point count locations during 1993 and 1994 breeding seasons.We also measured vegetation structure and composition at each location. Complete fire histories were available for each point, with over 80% having been burned one to four times in the previous 15 years. Post-fire succession generally transformed vegetation structure from short, sparse, and grassy with few forbs and low litter immediately after fire, to increasing and moderate amounts of forbs, litter, and shrubs two to eight years postfire, to tall, dense shrubby prairie with little forb, grass or litter understory when fire was absent (>80 years). Most grassland birds (six of nine species examined) at Lostwood NWR were absent from prairie untreated with fire. Species richness and abundances of Baird's Sparrows (Ammodramus bairdii), Bobolinks (Dolichonyx oryzivorus), Grasshopper Sparrows (A. savannarum), Le Conte'sSparrows (A. leconteii), Sprague's Pipits (Anthus spraguef), and Western Meadowlarks (Sturnella neglecta) were positively related to an index of amount of fire, and these species were absent from unburned units. In contrast, Common Yellowthroats (Geothlypis trichas) and Clay-colored Sparrows (Spizella pallida) both reached highest abundance on unburned prairie. To provide maximum grassland bird diversity, managers of mesic, mixed-grass prairie generally should provide areas with short (2-4 year), moderate (5-7 year), and long (8-10 year, or more) fire return intervals. Because long-term rest may create habitat unfavo [ABSTRACT FROM AUTHOR]

A pair of Cooper's Hawks (Accipiter cooperii) successfully fledged young from an unusually low nest in dense shrubs in northwestern NorthDakota. [ABSTRACT FROM AUTHOR]

A pair of Cooper's Hawks (Accipiter cooperii) successfully fledged young from an unusually low nest in dense shrubs in northwestern NorthDakota. [ABSTRACT FROM AUTHOR]