Lester D. Flake

Food Habits of Four Species of Rodents on a Short-Grass Prairie in Colorado

Food habits of four rodents ( Dipodomys ordii, Onychomys leucogaster, Peromyscus maniculatus , and Spermophilus tridecemlineatus ) of a short-grass prairie ecosystem in northeastern Colorado were studied in 1969 and 1970 through microscopic analysis of stomach contents. Mean per cent volumes of animal matter in diets of these rodents over the entire study were: D. ordii , 4.4 per cent; O. leucogaster , 73.9 per cent; P. maniculatus , 39.0 per cent; and S. tridecemlineatus , 44.0 per cent. The greatest amount of seasonal variation in per cent volume animal matter in the diet was in P. maniculatus . Animal matter in diets of all four species was composed almost entirely of arthropods and a few parts of vertebrates. The most common arthropods included adult and larval Coleoptera, larval Lepidoptera, and grasshoppers (except in D. ordii ). Plant matter in the diets of all species included leaves, stems, and flowering parts of various species of grasses, sedges, forbs, and shrubs, seeds (unidentified), and tissues of mosses, lichens, and fungi. Seeds were the most common type of plant matter in diets of D. ordii and P. maniculatus , whereas plant matter in S. tridecemlineatus and O. leucogaster was more equally divided between seeds and nonseed parts of grasses (and sedges) and forbs. Much seasonal variation in types and relative amounts of different kinds of plant and animal matter was noted.

DIURNAL VISIBILITY AND ACTIVITY OF BLUE-WINGED TEAL AND MALLARD BROODS1

Activities of blue-winged teal (Anas discors) and mallard (A. 1>latyrhynchos) broods were recorded continuously from sunrise to sunset in South Dakota during 1976. Observations totaling 255 brood-days were evaluated by species and age-class. Morning and evening feeding peaks became more pronounced, and visibility increased, with brood age. Swimming activity decreased, and visihle loaflng, sleeping, and depth of subsurface feeding increased in older broods. Behavior of class-I ducklings was similar in both species. Class-II and -III mallard broods loafed more and fed less in open water than did teal broods of the same age. Wind speeds in excess of 24 kmlhour and air temperatures above 23 C were associated with decreased brood visibility. Recommendations are made for increasing the accuracy and efficiency of brood inventories.

Grassland bird densities in seral stages of mixed-grass prairie

Abstract Birds associated with prairie ecosystems are declining and the ecological condition (seral stage) of remaining grassland communities may be a factor. Livestock grazing intensity influences the seral stage of grassland communities and resource managers lack information to assess how grassland birds are affected by these changes. We estimated bird density, species diversity, and species richness on 37 sites in 4 seral stages of western wheatgrass [Pascopyrum smithii (Rydb.) A. Löve]-green needlegrass [Nassella viridula (Trin.) Barkworth] communities of the Fort Pierre National Grassland. Bird species richness did not differ among seral stages (P = 0.57), but bird species diversity was greater (P < 0.10) in early seral stages compared to late-intermediate seral stages. Grasshopper sparrow (Ammodramus savannarum Gmlin), bobolink (Dolichonyx oryzivorus Linnaeus), dickcissel (Spiza americana Gmlin), and brown-headed cowbird (Molothrus ater Boddaert) density increased (P < 0.10) from early to late seral stages. Burrowing owl (Athene cunicularia Molina), upland sandpiper (Bartramia longicauda Bechstein), chestnut-collared longspur (Calcarius ornatus Townsend), and horned lark (Eremophila alpestris Linnaeus) density decreased (P < 0.10) from early to late seral stages. Western meadowlarks (Sturnella neglecta Audubon) were more abundant in early (P = 0.05) and early-intermediate (P = 0.01) seral stages than late seral stages. Birds with habitat requirements including tall vegetation and residual cover were more abundant in later seral stages. Early seral stages were beneficial to birds that prefer short grass and sparse vegetative cover. Seral stage was an effective predictor of density for many bird species. A mosaic that includes all seral stages is necessary to maximize grassland bird species diversity and abundance across the landscape. Managers can assess the effects on grassland birds of management actions that alter the seral stage of the vegetation.

Breeding Waterfowl Populations and Their Distribution in South Dakota

Ground counts and random sampling techniques were used to census breeding waterfowl populations in South Dakota in 1973 and 1974. The estimated total of breeding pairs was 1,067,500 in 1973 and 439,600 in 1974. Drought conditions occurred concurrent with the reduced 1974 populations. Blue-winged teal (Anas discors) was the major species, followed by mallard (A. platyrhynchos), pintail (A. acuta), and gadwall (A. strepera). Less than 5 percent of the total breeding pairs were diving ducks (Aythyini). Redhead (Aythya americana) was the primary diving duck species. Striking differences in densities of breeding pairs occurred among the major physiographic regions of the state. Waterfowl densities were highest in the glaciated eastern half of South Dakota, particularly in the northern periphery of the Coteau des Prairies and in the major portion of the Coteau du Missouri. Over 75 percent of the diving ducks were located on the Coteau des Prairies. The non-glaciated western half of the state had relatively low waterfowl densities but contained 20.7 percent of the total breeding pairs in 1973 and 30.8 percent in 1974. J. WILDL. MANAGE. 40(1):50-59 Specific information on the distribution and abundance of breeding waterfowl in South Dakota is important if waterfowl resources are to receive consideration in relation to current and future land and water development. North Americas prairie pothole region, within which most of the eastern half of South Dakota is included, has provided approximately one-half of the continental duck production from 10 percent of the total production area (Smith et al. 1964). Furthermore, South Dakota and North Dakota are the only prairie states that still retain a high proportion of their original prairie pothole wetlands (Burwell and Sugden 1964). The Dakotas are important among the contiguous 48 states in total waterfowl production and produce waterfowl that migrate to many other states, particularly in the Atlantic, Mississippi, and

Waterfowl Pair Use of Natural and Man-Made Wetlands in South Dakota

Use of natural ponds and lakes, streams, stock ponds, and dugouts by pairs of waterfowl was examined in South Dakota in May and June 1973 and 1974. Prairie ponds and lakes, primarily of glacial origin, comprised 75 and 68%, respectively, of the total area and number of wetlands in South Dakota. Stock ponds comprised 14% of the area and 21% of wetlands, and dugouts 1% and 12% of the wetland area and numbers, respectively. Semipermanent wetlands and stock ponds contained proportionally more pairs of most species than other wetland categories. Densities of blue-winged teal (Anas discors), pintails (A. acuta), northern shovelers (A. clypeata), and green-winged teal (A. crecca) declined sharply on semipermanent wetlands and stock ponds during the 1974 drought. Lack of water in ephemeral, temporary, and seasonal wetlands apparently decreased use of the remaining more permanent wetlands (natural or man-made) by these species. J. WILDL. MANAGE. 43(2):375-383 Pairs of waterfowl in South Dakota may exceed 1 million during spring in good water years, but major year-to-year fluctuations occur in response to wetland conditions (Brewster et al. 1976). Seventy percent or more of these pairs are associated with the glaciated portion of South Dakota east of the Missouri River; a part of the prairie pothole region of North America (Brewster et al. 1976). Glacial wetlands comprise the major wetland habitat in the state; however, many stock ponds and dugouts are also available. The purpose of this study was to investigate use of stock ponds, dugouts, streams, and various classes of glacial wetlands by pairs of waterfowl, and to inventory and determine the distribution of various wetland classes in South Dakota. This information is important in evaluating effects of past and present changes in wetland drainage and construction of stock ponds and dugouts. Similar studies were conducted in North Dakota (Stewart and Kantrud 1973, Kantrud and Stewart 1977). Financial support was provided by the South Dakota Agricultural Experiment Station (Project A-038-SDAK and B-045SDAK). We express appreciation to W. G. Brewster, G. D. Mack, and M. R. McEnroe for their assistance in data collection; to W. L. Tucker for providing recommendations on sampling procedures; and to K. F. Higgins, R. L. Linder, C. G. Scalet, and M. E. Anderson for their review and comments on the manuscript. We thank all the landowners who allowed access to their land.

Survival and habitat use by ring-necked pheasants during two disparate winters in South Dakota

Severe winter weather in the Northern Great Plains of North America can alter availability of winter cover and cause increased mortality of ring-necked pheasants (Phasianus colchicus). We monitored pheasant survival and habitat use via radiotelemetry during the second most severe winter in eastern South Dakota since 1892. We captured and radiomarked 48 female ring-necked pheasants at the onset of the 1996-97 winter and monitored survivors through spring at 3 sites in eastern South Dakota. We also monitored 58 female ring-necked pheasants at the same sites during the 1995-96 winter, a winter characterized by below average temperature and average snowfall (winter severity rank: 35th). Survival of radiomarked hens in 1995-96 (0.61 [SE = 0.07]) was higher (P 75 cm), cattail (Typha spp.) wetland, and corn food plot habitats in winter 1995-96, and early winter 1996-97. Shelterbelt and corn food plot ranked highest for pheasants that survived to the second half of the 1996-97 winter. We conclude that shelterbelt and food plot habitats are essential to the survival of pheasants in eastern South Dakota during extreme winter weather conditions.

A comparison of two waterfowl brood survey techniques

Aerial surveys, brood beat outs, road surveys, and brood observations have been used to estimate numbers of waterfowl broods (M. E. Anderson, unpubl. reps., South Dakota Dep. Game, Fish, and Parks Fed. Aid Proj. W-17-R-7 and 8,1953, 1955; Bennett 1967). M. C. Hammond (unpubl. rep., U.S. Bur. Sport Fish and Wildl., 1970) summarized several brood survey techniques and suggested that combining 2 or more techniques might be desirable for increased accuracy in some detailed waterfowl studies. The objective of this study was to compare 2 techniques, flush counts and hidden observation counts, for censusing duck broods on livestock watering ponds (stock ponds).

Merriam's Turkey Nest Survival and Factors Affecting Nest Predation by Mammals

Abstract Nest success is an important parameter affecting population fluctuations of wild turkeys (Meleagris gallopavo). Factors influencing mammalian predation on turkey nests are complicated and not well understood. Therefore, we assessed nest hazard risk by testing competing hypotheses of Merriams turkey (M. g. merriami) nest survival in a ponderosa pine (Pinus ponderosa) ecosystem during 2001–2003. We collected nesting information on 83 female Merriams turkeys; annual nest success averaged 50% for adult females (range = 45–59%) and 83% for yearling females (range = 75–100%). Proportional hazard modeling indicated that precipitation increased the hazard of nest mortality. However, estimated hazard of nest predation was lowered when incubating females had greater shrub cover and visual obstruction around nests. Coyotes (Canis latrans) were the primary predator on turkey nests. We hypothesize that precipitation is the best predictor of nest survival for first nests because coyotes use olfaction effectively to find nesting females during wet periods. Temporally, as the nesting season progressed, precipitation declined and vegetation cover increased and coyotes may have more difficulty detecting nests under these conditions later in the nesting period. The interaction of concealment cover with precipitation indicated that nest hazard risk from daily precipitation was reduced with greater shrub cover. Management activities that promote greater shrub cover may partially offset the negative effects of greater precipitation events.

Management considerations to enhance use of stock ponds by waterfowl broods.

Use of 36 livestock watering ponds by mallard (Anas playtrhynchos), blue-winged teal (A. discors), and total broods was tested against 32 habitat variables from 1977 and 1978. Pond size, shallow water areas with submersed vegetation, number of natural wetlands in a 1.6-km radius, and emersed vegetation composed of smartweed (Polygonum spp.) and spikerush (Eleocharis spp.) were associated with increased use of ponds by total broods. When analyzed by species, small grain on the surrounding section and height and density of shoreline vegetation were associated with increased use of ponds by mallard broods; percent of shoreline with trees and percent arrowhead (Sagittaria spp.)/water plantain (Alisma spp.) were associated with decreased use of ponds by mallard broods. Percent river bulrush (S. cirpus fluviatilis)/burreed (Sparganium spp.) was associated with decreased use of ponds by blue-winged teal.

HABITAT OF BIRDS IN PONDEROSA PINE AND ASPEN/BIRCH FOREST IN THE BLACK HILLS, SOUTH DAKOTA

Abstract Birds with both eastern and western distributions occur in the Black Hills of western South Dakota. This forest is mostly ponderosa pine (Pinus ponderosa) and is managed for timber. Logging alters forest characteristics and the bird community. We studied habitat relations of breeding songbirds at the stand- and site-level scales in ponderosa pine and quaking aspen (Populus tremuloides)/paper birch (Betula papyrifera) forest. Sixty bird species were observed ≤50 m from count points. Species richness was greater in aspen/birch than in ponderosa pine. Species richness was generally lower in ponderosa pine with >40% overstory canopy cover (OCC) than in ponderosa pine with ≤40% OCC and than aspen/birch of any structural stage. Seven bird species were associated with the ponderosa pine, while four species were associated with aspen/birch. Bird associations at the stand-level were further refined by OCC and diameter-at-breast-height (DBH) structural stage of each forest type. Habitats for most birds in the Black Hills can be managed using current forest inventory descriptions that include OCC and DBH. However, Red-naped Sapsuckers (Sphyrapicus nuchalis), Red-breasted Nuthatches (Sitta canadensis), White-breasted Nuthatches (S. carolinensis), Ovenbirds (Seiurus aurocapillus), and Western Tanagers (Piranga ludoviciana) were strongly associated with site-level vegetation characteristics. Snag density, snag condition, and deciduous trees beneath the ponderosa pine canopy should be included in forest inventories to better quantify habitats for these birds.