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Macgillivray's Warbler In Cedar County, Nebraska, Mark A. Brogie, David A. Stage

Nebraska Bird Review

MacGillivray's Warbler (Oporornis tolmiei) is considered by Johnsgard (1980) to be a rare spring and fall migrant in western Nebraska. with most records from the Panhandle. but reported from as far east as Platte Co. Bray et al (1986) consider it regular and cite a specimen taken in Boone Co.. Whatever the status. this warbler is infrequently encountered in Nebraska. and separating this species from Mourning Warbler (Oporornis philadelphia) can often be difficult. Some authorities believe the two to be conspecific, although Hall (1979) found very few hybrid specimens and Salt (1973) found that they did …

The Eighty-Sixth (1987) Annual Meeting

Nebraska Bird Review

The eighty-sixth Annual Meeting was held in Valentine 15, 16, and 17 May, 1987, in conjunction with the South Dakota Ornithologists' Union. A previous joint meeting was held in Yankton, S. D. in 1959. Total attendance at some part of this meeting was 116; 6 who were members of both societies, 57 members of NOU only, 39 members of SDOU only, and 14 nonmembers. Friday night George Vandel, of the SD Game, Fish, and Parks Commission, spoke on the program, sponsored by the International Association of Fish and Wildlife Agencies, for the identification and preservation of shorebird habitat. At the …

Karyotypic Analysis Of Five Rodents And A Marsupial From Belize, Central America, David W. Burton, John W. Bickham, Hugh H. Genoways, Timothy J. Mccarthy

University of Nebraska State Museum: Mammalogy Papers

Karyotypes and chromosomal banding patterns of six species of small mammals from Belize are presented and discussed in light of relevant data in the literature. Individuals of Heteromys desmarestianus had FN values of 72, which differs from previous reports. G-bands were obtained and compared to fluorescent bands (DAPI) and with the location of NOR sites. The karyotypes of Peromyscus mexicanus, Sigmodon hispidus, Oryzomys couesi, and Ototylomys phyllotis are identical to the karyotypes for these species described in the literature. Active NORs were located on four pairs of chromosomes in O. phyllotis and fluorescent bands obtained with the …

Kentucky Warbler (Vol. 63, No. 2), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.

Comparisons Of Performance & Carcass Traits Of Littermate Boars & Barrows, Hiromi Hirano

Masters Theses & Specialist Projects

The purpose of this study was to determine differences between littermate boars and barrows for performance and carcass traits in the Iowa and Northeast Iowa Swine Testing Stations. Data were obtained from 917 litters including 1,804 boars and 917 barrows. The data included 1,086 boars and 581 barrows from the Iowa Station at Ames, Iowa, and 718 boars and 336 barrows from the Northeast Iowa Station at New Hampton, Iowa. The Iowa Station data were obtained over a period of 12 seasons from the fall of 1979 through the fall of 1985, and the data from the Northeast Iowa Station …

Comparing Different Methods For Determining Moisture In Wheat Using Nesr Infrared Reflectance Spectroscopy, Weider Chang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One hundred wheat samples, with moisture ranging from 14.42 %to 7.66 %, were used to test the moisture loss from grinding, the accuracy of moisture content from two different electric moisture meters, and the accuracy and precision of Near Infrared Reflectance Spectroscopy whole wheat moisture determination.

Fifty samples were ground through three grinders, Wiley, Cemotec, and UDY Cyclone grinder. Moisture content was determined from these ground samples, and compared with whole wheat moisture. The Cemotec grinder caused the least amount of moisture loss, followed by Wiley and then UDY Cyclone.

Fifty whole wheat samples were used to calibrate the Tecator …

Wood And Forage Production In Cleared And Thinned Dry Tropical Woodland: Implications To Goat Nutrition, Walter H. Schacht

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wood for firewood, fence posts and construction material and forage for domestic livestock are key resources in the caatinga vegetation zone of northeastern Brazil. This experiment was designed as a preliminary assessment of thinned caatinga as the basis of a production system which optimizes forage and wood production. Two levels of thinning (25% and 55% tree canopy cover) were compared to cleared (0% tree canopy cover) and undisturbed (95% tree canopy cover) caatinga in terms of forage and wood production and goat nutrition.

Clearing and thinning of caatinga vegetation resulted in higher amounts of available forage through the wet ·season …

Effects Of Grazing Intensity By Sheep On The Production Of Atriplex Nummularia And Sheep Live Weight In Jordan, Kamal I. Tadros

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rangelands in Jordan are deteriorated due to a combination of harsh environmental conditions and human misuse. Jordan is importing increasingly large quantities of meat and animal products to meet the demand from its growing population. Sheep are supplementarily fed during the dry season and large quantities of grain supplements are imported every year.

Significant success has been attained in the establishment of Atriplex nummularia Lindl. (ATNU) in Jordan. There is, however, a general lack of adequate research to determine if ATNU is effectively utilized by local sheep, to what extent it is utilized and to what extent it tolerates grazing. …

Economic Aspects Of Reproductive Problems In Utah And Southeastern Idaho Dairy Herds, Steve Lemrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One hundred eighty-seven survey questionnaires asking for reproductive information for 1985 were sent to dairymen in Utah and Southeastern Idaho. Forty- two herds with current DHI information and whose owners or managers completed and returned the questionnaire were used to estimate economic losses due to reproductive problems, especially excessive days open, in Utah and Southeastern Idaho.

Average days open for herds surveyed were 122.4 days with a standard deviation of 22.6 days, and a range of 89 to 177 days. Several factors were significantly correlated with days open including services per conception, previous calving interval, and missed heats. Missed heats …

Comparative Study Of Elongated Chromosomes In Sheep And Goats And A Proposed Standard, Stephen H. Mensher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A cell synchronization technique was used that consistently yielded numerous elongated chromosomes, which are necessary for producing high-resolution G-banding. The prometaphase stage of contraction was determined to have the greatest utility for detailed comparative analysis and, therefore, was used in the preparation of the proposed standard high-resolution karyotypes and idiogram.

A proposed standard high-resolution G-band karyotype of the domestic sheep and goat is presented, along with a high-resolution G-band idiogram of the goat. The karyotypes presented contain considerably more bands than contemporary karyotypes and provide much greater resolution for linear differentiation. The X chromosome of the sheep is acrocentric, rather …

Selected Parameters Of Reproduction In Rambouillet And St. Croix Ewes, Ronald Cole Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experiments were conducted to determine the genetic reproductive potential of Rambouillet and St. Croix ewes . Ovulation rate (monthly) and estrus (daily) were observed for two years on 10 ewes of each breed to establish seasonal patterns . Both breeds demonstrated seasonal anestrus from May through July. Ovulation rates reached 2.0 or greater for both breeds during September to November, and decreased to 1.25 by March. Breeding groups for St. Croix and Rambouillet ewes were bred each February and August for five years to establish lambing performance at six month intervals. Age at first lambing was earlier for St. Croix …

Compounds In Bovine Urine Which Change In Concentration During The Estrous Cycle: Possible Pheromones, Scott Kay Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the last thirty years it has become increasingly apparent that pheromones play a major role in animal communication. Of economic interest to agriculturalists is the role pheromones play in signaling the state of estrus. The ability to efficiently detect estrus is becoming increasingly important, especially in the management of dairy and beef herds, where artificial insemination is used extensively. The understanding of pheromones may eventually provide a solution to this problem.

The purpose of this study was to identify one or more compounds in the urine of cattle which undergo a change in concentration during the estrous cycle.

In …

Adaptation Of Striped Bass To Sea Water Following Direct Transfer From Freshwater: Morphological, Biochemical, And Physiological Parameters, Judy A. King

Electronic Theses and Dissertations

There has been heightened interest in the biology of striped bass (Morone saxatilis) because of increased pollution in their native spawning grounds and because of their extensive use in landlocked sport fisheries. Their euryhalinity makes them an excellent species for osmoregulation studies. The objective of this research was to study the rate of adaptation of striped bass gills to sea water (3% salt) after direct transfer from freshwater using biochemical (ion transport enzyme levels), physiological (chloride efflux), and ultrastructural methods. Striped bass have specialized osmoregulatory cells located on the interlamellar and afferent surfaces of their gill filaments as shown by …

Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry

Dartmouth Scholarship

As a population, Cocos Finches exhibit a broad range of feeding behaviors spanning those of several families of birds on the mainland, while individuals feed as specialists year-round. Although this extreme intraspecific variability occurs as predicted in a tropical oceanic island environment, these specializations challenge contemporary ecological theory in that they are not attributable to individual differences in age, sex, gross morphology, or opportunistic exploitation of patchy resources. Instead, they appear to originate and be maintained behaviorally, possibly via observational learning. This phenomenon adds another direction to the evolutionary radiation of the Darwin's Finches and underscores the necessity for detailed …

Bird Territories: A Key To Understanding Bird Behavior, Robert A. Askins

Biology Faculty Publications

No abstract provided.

Diving Birds Of North America: 5 Comparative Pair-Forming And Copulatory Behaviors, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

All species of loons, grebes, and auks are monogamous, with adults forming strong pair bonds that are established or reestablished each year, probably during the spring prenesting period. The extent of remating by birds mated the previous year in these groups is still largely undocumented, though at least in alcids it is fairly high, given the relatively long life-spans and the tendencies of the birds to return year after year to essentially the same territory and sometimes to the same nest site. Such conditions would promote reestablishment of contracts between previously paired birds, since it is not believed that in …

Diving Birds Of North America: Literature Cited, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

14 pages, with more than 500 references.

Animal Brutality For Fun And Profit

Close Up Reports

HSUS field staff cracks down on bizarre animal spectacles

Diving Birds Of North America: Frontmatter, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Contents
List of Illustrations and Tables
Preface

Diving Birds Of North America: Species Accounts — Loons (Gaviidae), Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Loons are large diving birds having long, straight, and acutely pointed bills, with feathers covering the lores (region between eye and bill) and extending to the linear nostrils. There are 10 functional primaries and 22–23 secondaries, the inner secondaries shorter than the primaries. Molting of the remiges (flight feathers) is simultaneous, and the wings are not used for underwater propulsion. The 16–20 rectrices (tail feathers) are short and stiff. The body feathers are shiny and water-resistant; aftershafts and adult down feathers are present. The legs are set extremely far back on the body, making standing very difficult and walking or …

Diving Birds Of North America: Species Accounts — Grebes (Podicipedidae), Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Grebes are small to medium-sized diving birds having bills that vary from short and rather blunt tipped to long and acutely pointed, with bare lores and head feathers not extending to the linear or oval nostrils. There are 11 functional primaries and 17–22 secondaries, the inner secondaries longer than the primaries. Molting of the primaries is simultaneous; the wings are not used for underwater propulsion, which is provided by the feet. The rectrices are soft, rudimentary, and hidden. The body feathers are small, water-resistant, and shiny. Aftershafts and adult down feathers are present. The legs are set extremely far back …

Diving Birds Of North America: 3 Comparative Egocentric And Locomotory Behaviors, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

As used here, "egocentric behavior" means those categories of individual survival and maintenance behaviors that are exclusive of such social interactions as aggressive, sexual, and parental behaviors, which will be considered in detail in the individual species accounts and also will be separately summarized in chapter 5. A discussion of the ecological aspects of foraging behavior will also be deferred until chapter 4, though behavioral aspects of underwater locomotion and prey catching will be considered here.

Diving Birds Of North America: 1 General Attributes And Evolutionary Relationships, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Loons, grebes, and auks comprise a rather large number of species of aquatic diving birds that are fairly unfamiliar to most people, inasmuch as they tend to spend much of their time well away from shore and, when approached on the water, usually dive inconspicuously and reappear a considerable distance away. Thus in many areas grebes, simply called "helldivers," are often confused with coots or even diving ducks. Many people know loons only by their wild, penetrating cries and romantically associate them with northern woods and lakes, while auks are symbolic of arctic coastal cliffs. But ornithologists can find fascinating …

Diving Birds Of North America: 4 Comparative Diets And Foraging Ecologies, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Auks, loons, and grebes are birds whose anatomies and behaviors have been sharply influenced by their foraging niche adaptations. In each species these have evolved through natural selection over extended periods of geologic time as a reflection of available food resources, the presence of competing species, and the limitations on innate variations in anatomy, physiology, and behavior imposed by available genetic mutations and recombinations. To a very considerable degree the auks, loons, and grebes seem to have adjusted to the effects of interspecific competition by evolving differences in bill shape and body size that sometimes open specific new foraging niche …

Diving Birds Of North America: Index, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

This index is limited to the English vernacular and Latin names of species and subspecies of loons, grebes, and auks discussed individually in this book. Complete indexing is confined to entries for the English vernacular names of species as used in this book. The principal account of each species is indicated by italic page numbers.

[Publisher’s note: The PDF files of the complete book and all chapters have been converted to text via optical character recognition, and may be word-searched from Adobe Reader or Acrobat.]

Diving Birds Of North America: Appendices, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Sources of Scientific and Vernacular Names
Keys to Identification of Loons, Grebes, and Auks
Key to Families of Loons, Grebes, and Auks
Key to Species of North American Loons
Key to Species of North American Grebes
Key to Species of North American Auks
Major North American Auk Colonies
Summer Abundance and Breeding Status of Grebes at Selected National Wildlife Refuges

Diving Birds Of North America: Species Accounts — Auks (Alcidae), Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Auks are small to medium-sized diving birds having bills that are variably pointed and compressed but never acuminate and are sometimes covered with colorful horny sheaths in breeding adults. Feathering densely covers the lores and often extends to the nostrils, which vary from linear to oval. There are 10 functional primaries and 15–19 secondaries; the greater secondary and primary coverts are usually lengthened. Molting of the primaries is usually simultaneous but is gradual in some species; the wings are used for underwater propulsion, and the feet are then used mainly for steering. The 12–18 rectrices are short and normal in …

Diving Birds Of North America: 2 Comparative Distributions And Structural Adaptations, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

The geographic distributions of the loons, auks, and grebes are primarily reflections of the evolutionary histories of each of the groups, past climatic and geologic phenomena, and present-day climatic and ecological conditions. Thus all the loons and auks are Northern Hemisphere birds, which presumably have never been able to bridge the tropical barrier into the Southern Hemisphere, where seemingly suitable breeding habitat might exist in, for example, southern South America and Tierra del Fuego. Indeed, the breeding distribution of the Northern American loons is distinctly arctic oriented, with the greatest species density north of the boundaries of arctic tundra in …

Diving Birds Of North America: Color Plates, Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

1. Arctic loon, adult in breeding plumage. Photo by author.
2. Red-throated loon, nesting adult. Photo by Kenneth W. Fink.
3. Yellow-billed loon, adult in breeding plumage. Photo by Kenneth W. Fink.
4. Common loon, nesting adult. Photo by Kenneth W. Fink.
5. Pied-billed grebe, adult in breeding plumage. Photo by author.
6. Least grebe, adult and young. Painting by Mark E. Marcuson.
7. Red-necked grebe, nesting adult. Photo by author.
8. Eared grebe, adults with young. Photo by Kenneth W. Fink.
9. Horned grebe, nesting adult. Photo by Kenneth W. Fink.
10. Western grebe, adult with young. Photo by …

Diving Birds Of North America [Complete Book], Paul A. Johnsgard

Diving Birds of North America by Paul A. Johnsgard

Considering the great nostalgic attraction of such birds as the common loon for people who have lived at least part of their lives around the lakes of Canada and the northern United States, and given the endearing visual appeal of species like puffins and auklets, it is rather surprising that there are so few books on these groups of aquatic birds. During my childhood summers at our Minnesota lake cottage I used to spend hours watching loons and red-necked grebes, and I marveled at their wonderful diving ability and powerful voices. Much later, the wild puffins and massed breeding colonies …