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Alternatives To Fisher's "Exact Test" For Analyzing 2 X 2 Tables With Small Cell Sizes, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Rice (1988a) presents an interesting test for analyzing 2 X 2 contingency tables in the smaller sample size situations. His motivation was to provide an alternative to Fisher's "exact test" and his rationale was based on the application of a prior distribution to the probability of a success, 0, under the null hypothesis. We would like to briefly comment on these aspects of his paper and also discuss another alternative that was proposed a number of years ago.

Boreal Toad In Clear Creek County, Colorado, Richard M. Engeman, Robert W. Connell

United States Department of Agriculture Wildlife Services: Staff Publications

Many amphibian populations worldwide have experienced recent population declines (e.g. Barinaga 1990). Included among these are declines for the boreal toad (Bufo boreas boreas) in the central Rocky Mountains (Corn et al. 1989; Stolzenburg 1989). The extent of the population declines is such that boreal toad populations in the Rocky Mountains have been included on the list of species to be reviewed by the U.S. Fish and Wildlife Service for Threatened or Endangered status (Federal Register 1989). We report here an additional population site for the boreal toad in Colorado.

Herring Gulls, Larus Argentatus, Nesting On Sandusky Bay, Lake Erie, 1989, Richard A. Dolbeer, P.P. Woronecki, T. W. Seamans, B. N. Buckingham, E. C. Cleary

United States Department of Agriculture Wildlife Services: Staff Publications

One of the largest herring gull (Larus argentatus} nesting populations on the Great Lakes is located in an urban setting on Sandusky Bay in the Ohio portion of Lake Erie. The survey reported here, carried out in 1989, indicated a population of 4,250 nests. The population has expanded from a focal point on Turning Point Island to coal piles at the Lower Lake Dock Company, rooftops in downtown Sandusky and breakwalls near Cedar Point. Comparison with data from a survey performed in 1976 indicates the population has grown at an average annual rate of 11.9% during the past 13 years. …

Biochemical And Morphological Characteristics In Maturing Achenes From Purple-Hulled And Oilseed Sunflower Cultivars, Roger W. Bullard, Paul P. Woronecki, Richard A. Dolbeer, J. Russell Mason

United States Department of Agriculture Wildlife Services: Staff Publications

The blackbird feeding preference for sunflower oilseed variety Jacques Discovery (JD) over purple-hulled Neagra de Cluj (NdC) has been attributed to anthocyanin. To test this hypothesis, we compared biochemical and morphological properties in the achene over the maturation period. Comparisons included total phenols, anthocyanin, tannin, fat/oil, protein, nonstructural sugars, and phytomelanin contents, as well as mass properties and moisture content. Only three differences were observed: (1) Hull mass was significantly higher for NdC than JD. (2) Anthocyanins were synthesized by NdC only. (3) JD was higher in oil content. Each of these factors may play a role in reduced preferences …

The Use Of Banding Recovery Data To Estimate Dispersal Rates And Gene Flow In Avian Species: Case Studies In The Red-Winged Blackbird And Common Grackle , William S. Moore, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Dispersal resulting in gene flow strongly affects the evolution of genetic structure in populations. This report describes statistical estimators of dispersal parameters based on USFWS banding recovery records. Finite-area studies of avian species yield estimates of root-mean-square (RMS) dispersal along a transect of about 1 km per generation. In contrast, estimates of RMS dispersal for the Red-winged Blackbird (Agelaiusp hoeniceus) and Common Grackle (Ouiscalus auiscula), based on USFWS banding recovery records, are 94.6 and 111.4 km per generation, respectively. Distributions for both species are extremely leptokurtic, and confidence intervals based on jackknife statistics are large because the estimators are sensitive …

Blackbird And Starling Feeding Behavior On Ripening Corn Ears, Glen E. Bernhardt, Lynda Van Allsbur, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

The behavior of red-winged blackbirds {Agelaius phoemcei/s), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater), and juvenile European starlings (Sturnus vulgaris) feeding on ears of corn was studied in an aviary. The species differed significantly in their propensity to attack (penetrate the husk and feed on kernels) ears of corn. Redwings and starlings were more active attackers than grackles and cowbirds. Female redwings were generally more active attackers than males, but less efficient at opening husks and damaging ears. Redwings and starlings used primarily the gaping technique to penetrate husks and expose kernels. Redwings more commonly penetrated the side of …

Sex-Specific Feeding Habits Of Brown-Headed Cowbirds In Northern Ohio In January, Richard A. Dolbeer, Cynthia R. Smith

United States Department of Agriculture Wildlife Services: Staff Publications

We examined the stomach contents of 57 brown-headed cowbirds (Molothrus ater) collected from a roost in Erie Co., Ohio, on 12 January 1983. Corn was by far the predominant food, averaging 66% of the stomach contents by weight. Seeds from at least five grasses, but primarily Setaria spp., were the second most abundant food category, averaging 21% of the stomach contents. Ragweed {Ambrosia artemisiifolia) seeds (2.6%) were third. Male cowbirds consumed more corn than did the smaller females, whereas females consumed more of the smaller grass seeds. The abundance of corn in harvested fields and feedlots, combined with mild winter …

Survival Analysis For A Red Squirrel Population, Curtis H. Halvorson, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

A 13-year study of an isolated red squirrel (Tamiasciurus hudsonicus) population in Montana has provided the data necessary to analyze their survival. Such long-term, intensive studies of wild populations are rare. When reported, derived (ratio) estimates are used to develop survival information as Gross et al. (1974), and Keith and Windberg (1978) did in respective 9- and 15-year lagomorph studies. A more accurate method, following cohorts, was used by Armitage and Downhower (1974) and Mosby (1969), who presented results for six or more year-classes of sciurids in actuarial tables (Deevey, 1947; Allee et al., 1949).

Serum Concentrations Of Pituitary And Adrenal Hormones In Female Pigs Exposed To Two Photoperiods, Robert R. Kraeling, George B. Rampacek, John W. Mabry, Fred L. Cunningham, Carl A. Pinkert

United States Department of Agriculture Wildlife Services: Staff Publications

Serum concentrations of pituitary and adrenal hormones were determined in lactating sows and ovariectomized (OVX) gilts exposed to 8 h (8L:16D) or 16 h of light (16L:8D). In addition serum prolactin (PRL) concentrations were determined after a thyrotropin releasing hormone (TRH) challenge. At 103 -+ 2 d of gestation or 3 wk after ovariectomy of nullipai'ous gilts on d 7 to 9 of the estrous cycle (d -10), blood samples were collected from jugular vein cannulae at 30-rain intervals for 8 h beginning at 0800 h. Immediately after the last sample, 13 sows and five OVX gilts were assigned to …

Migration Patterns For Age And Sex Classes Of Blackbirds And Starlings, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Red-winged Blackbirds (Agelaius phoeniceus), Brown-headed Cowbirds (Molothrus ater), and Starlings (Sturnus vulgaris) are ubiquitous breeding birds in much of North America. The Common Grackle (Quiscalus quiscula) is an abundant breeding bird east of the Rocky Mountains (Dolbeer and Stehn 1979). Although these species are widely dispersed and generally unassociated during the nesting season, they often associated closely in winter roosts containing up to 10 million birds in the southern United States (Meanley and Webb 1965, Meanley 1971). Little is known about the comparative migration patterns of the four species and the resulting mixture of local breeding populations in winter. Comparative …

In Search Of A Diversity Ethic For Wildlife Managemen, Fred B. Samson, Fritz L. Knopf

United States Department of Agriculture Wildlife Services: Staff Publications

As the century nears its end and demand for food and competition for land escalate, a most important issue facing conservationists will be the preservation of a mosaic of habitats in which can be preserved a representative cross-section of native species. The need to resolve this issue is emphasized in the Global 2000 Report to the President (Council on Environmental Quality 1980) which predicts that, worldwide, 500,000 to 2 million species will become extinct by the year 2000 and that the rate will increase from one per day in 1980 to one per hour by century's end (Myers 1979). Although …

The Effect Of Artificially Extended Photoperiod During Lactation On Maternal Performance Of The Sow, John W. Mabry, Fred L. Cunningham, Robert R. Kraeling, George B. Rampacek

United States Department of Agriculture Wildlife Services: Staff Publications

A 20-stall farrowing facility was partitioned into two separate rooms of 10 stalls each so that photoperiod could be controlled. In addition, temperature and air movement were equalized in the two rooms. The two light regimens utilized were 8 h light: 16 h dark, and 16 h light:8 h dark. A total of 26 sows in two replicates were used. Females were moved into the facility on d 103 -+2 of pregnancy, litters were equalized at birth and weaning was at 28 d of age. Traits evaluated included litter size at birth and weaning, 21-d pig and litter weights, milk …

Mustela Nigripes, Conrad N. Hillman, Tim W. Clark

United States Department of Agriculture Wildlife Services: Staff Publications

CONTEXT AND CONTENT. Order Carnivora, Family Mustelidae, Genus Mustela, Subgenus Putorius. There are about 14 living species of Mustela including three of Putorius. No subspecies of M. nigripes have been recognized.

DIAGNOSIS. Mustela nigripes is about mink-sized; upper parts are yellowish buff, occasionally whitish, especially on the face and venter (Fig. 1); feet are black; tail is tipped with black; mastoid process is notably angular (Fig. 2) (Long, 1965). Ferrets (subgenus Putorius) differ from other Mustela (weasels and mink) in being larger than weasels and in having the following combination of characters: ventral and dorsal pelage without …

Blackbirds And Corn In Ohio, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Damage to corn by blackbirds (Icteridae) has been an economic problem throughout historical times in North America. Ohio, with the highest nesting season population density of red-winged blackbirds (Agelaius phoeniceus) in North America and large acreages of corn, has been a key state in this conflict. Survey of damage from 1968 to 1979 revealed that blackbirds annually destroyed less than 1% of the corn crops in Ohio, a 4- to 6-million dollar loss at 1979 prices. This total dollar loss is somewhat misleading because of the uneven distribution of damage among fields. Over 97% of the cornfields in …

Compensatory Response Of Maturing Corn Kernels Following Simulated Damage By Birds, Paul P. Woronecki, Robert A. Stehn, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

(1) A study was made to measure compensatory growth responses and to estimate losses associated with bird damage to maturing corn.
(2) Corn kernels contain 20-40% of their final biomass at the time they are usually consumed by blackbirds.
(3) Very slight compensation of kernel weight occurred following simulated bird damage to tip kernels.
(4) Heavy bird damage, early in kernel development, increased fungal, sprouting, and insect damage before harvest.
(5) Estimates of bird damage, subsequent secondary damage, and compensation were affected by the amount of damage, maturity of the kernels at the time of damage, and environmental factors before, …

Hazards To Wildlife Associated With 1080 Baiting For California Ground Squirrels, Paul L. Hegdal, Thomas A. Gatz, Kathleen A. Fagerstone, James F. Glahn, George H. Matschke

United States Department of Agriculture Wildlife Services: Staff Publications

Under an Environmental Protection Agency (EPA) Interagency Agreement, we evaluated the hazards to wildlife associated with aerial 1080 (sodium monofluoroacetate) baiting for California ground squirrels (Spermophilus beecheyi fisheri). We conducted the study in Tulare County, in south-central California, in the eastern foothills of the San Joaquin Valley. Vegetation is annual range grasses and associated forbs, under open stands of oak (Quercus spp.), with cottonwood (Populus spp.), California sycamore (Platanus racemosa), and California buckeye (Aesculus californica) along stream bottoms. The study monitored a large-scale operational baiting program conducted in Tulare County by the …

Agricultural Impact Of A Winter Population Of Blackbirds And Starlings, Richard A. Dolbeer, Paul P. Woronecki, Allen R. Stickley Jr., Stephen B. White

United States Department of Agriculture Wildlife Services: Staff Publications

The major concentration of blackbirds and Starlings (Sturnus vulgaris) in North America occurs in the southeastern United States where an estimated 350 million Red-winged Blackbirds (Agelaius phoeniceus) , Common Grackles (Quiscalus quiscula) , Brown-headed Cowbirds (Molothrus ater) , and Starlings congregate in winter roosts (Meanley 1971, 1975, 1977). An estimated 75-100 major (containing >l million birds) roosts form in the southeastern states each year. Increasing attention is being given to many of these roosts because of nuisance problems, reputed health hazards, and agricultural damage associated with them. Although considerable effort has been directed toward developing methods for reducing roosting populations …

Movement And Migration Patterns Of Red-Winged Blackbirds: A Continental Overview, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

From 1924 through 1974, about 11,000 recoveries accumulated from the banding of over 700,000 Red-winged Blackbirds(Agelaius phoeniceus) in North America. A few studies have examined some of these data for specific localities during certain times of the year; however, no attempt has been made to examine the total recovery data to compile a general picture of continental movement and migration patterns. Increasing attention is being given to blackbird (Icteridae) and Starling (Sturnus vulgaris) populations in North America because of their reported crop depredations, health hazards, and nuisance aspects, especially when congregating in large roosts (Meanley,1975;Graham, 1976). Solutions to these problems …

Reproduction In The Red Squirrel (Tamiasciurus Hudsonicus) In Colorado, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

Information on reproduction of the red squirrel (Tamiasciumrs hudsonicus) can be gleaned from studies in the northeastern United States (Klugh, 1927; Hamilton, 1939; Layne, 1954) and in western Canada (Miller, 1970; Smith, 1968; Kemp and Keith, 1971; Wood, 1967). However, there is a paucity of information on reproduction from the mountainous regions of the western United States. This paper presents reproductive information on the red squirrel from Colorado and helps fill this void. In addition, the reproductive strategy of red squirrels is briefly compared with that of snowshoe hares.

Winter Behavior Of The Eastern Box Turtle, Terrapene C. Carolina L., In Eastern Tennessee, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

A field study of winter movements and depths and types of hibernacula of the eastern box turtle, Terrapene carolina carolina L., was undertaken from October 1968-January 1969.