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Erau Spring 2013 Newsletter, Paul Eschenfelder Jan 2013

Erau Spring 2013 Newsletter, Paul Eschenfelder

Paul F. Eschenfelder

No abstract provided.


Rocky Mountain Birds: Birds And Birding In The Central And Northern Rockies, Paul A. Johnsgard Jul 2012

Rocky Mountain Birds: Birds And Birding In The Central And Northern Rockies, Paul A. Johnsgard

Paul Johnsgard

“The Rocky Mountain region has fascinated me ever since I traveled to Glacier and Yellowstone National Parks as a teenager, and saw for the first time such wonderful birds as ospreys, American dippers, and Lew­is’s woodpeckers.” This book is in part based on the author’s earlier Birds of the Rocky Moun­tains (1986, revised 2009), but over a third of the original text has been eliminated. The rest has been updated, expanded and modified to be less technical and more useful to birders in the field. Bird enthusiasts will find viewing loca­tions and updated contact information for hundreds of sites in …


A Nebraska Bird-Finding Guide, Paul A. Johnsgard Jul 2012

A Nebraska Bird-Finding Guide, Paul A. Johnsgard

Paul Johnsgard

Nebraska lies in the transition zone between North American eastern and western avifaunas and is home to more than 200 breeding and 150 migrant species. This definitive guide to Nebraska birdwatching by the state’s preeminent ornithologist includes a county-by-county rundown of the best sites, a calendar of migrations, an annotated checklist of regularly occurring Nebraska birds, and recommendations for optical equipment, publications and reference materials, and contact information for conservation and ornithological groups. It features 48 maps as well as photographs and drawings by the author. Paul Johnsgard, Foundation Professor Emeritus of Biological Sciences at the University of Nebraska–Lincoln, is …


Development Of Endothermy In Nestling Bank Swallows (Riparia Riparia), Richard L. Marsh Dec 2010

Development Of Endothermy In Nestling Bank Swallows (Riparia Riparia), Richard L. Marsh

Richard Marsh

Body temperature (Tb) measurements after exposure to air temperatures (Tₐ) of 20 C or 27 C for 2 h in conjunction with metabolism measurements were used to describe the timing of and basis for developing temperature regulation in nestling swallows. As growth proceeds from hatching to 10 g there is a gradual increase in the Tb after exposure to low Tₐ. As growth continues beyond this point, the ability of nestlings to maintain Tb above Tₐ improves rapidly, such that nestlings weighing over 14 g are completely homeothermic when exposed to 20 C. Conductance (C, in cal [g⋅h⋅°C]⁻¹) decreases throughout …


Effects On Nestling Age And Burrow Depth On Co₂ And O₂ Concentrations In The Burrows Of Bank Swallows (Riparia Riparia), Steven J. Wickler, Richard L. Marsh Dec 2010

Effects On Nestling Age And Burrow Depth On Co₂ And O₂ Concentrations In The Burrows Of Bank Swallows (Riparia Riparia), Steven J. Wickler, Richard L. Marsh

Richard Marsh

Gas samples were taken from the nest chambers of bank swallows (Riparia riparia) and analyzed for CO₂ and O₂ content. The mean CO₂ content was 2.62% with a maximum value of 5.58%, and the mean O₂ content was 17.83% with a minimum value of 14.61%. There was a positive and significant correlation of increasing CO₂ content with both increasing nestling age and increasing total metabolizing mass (adults plus young). With increasing metabolizing mass there is a linear increase in CO₂ content, which suggests no active regulation of gas concentrations. Burrow depth also affected CO₂, particularly in burrows with older nestlings. …


Winter Fattening In The American Goldfinch And The Possible Role Of Temperature In Its Regulation, William R. Dawson, Richard L. Marsh Dec 2010

Winter Fattening In The American Goldfinch And The Possible Role Of Temperature In Its Regulation, William R. Dawson, Richard L. Marsh

Richard Marsh

We investigated whether environmental temperature has any causal role in the winter fattening in certain finches of the subfamily Carduelinae. Correlational analyses between fat content of American goldfinches (Carduelis tristis) and various short- and long-term measures of temperature provide no evidence for a proximate role of this environmental variable in determining the degree of fattening of these birds in southeastern Michigan. Their fat content shows the best correlations (r = −.61 to −.63) with the long-term average minimum temperature or record low temperature for the date of capture. Furthermore, inclusion of long-term thermal measures in multivariate analyses excludes from significance …


Adaptations Of The Gray Catbird Dumetella Carolinensis To Long-Distance Migration: Flight Muscle Hypertrophy Associated With Elevated Body Mass, Richard L. Marsh Dec 2010

Adaptations Of The Gray Catbird Dumetella Carolinensis To Long-Distance Migration: Flight Muscle Hypertrophy Associated With Elevated Body Mass, Richard L. Marsh

Richard Marsh

The size and composition (lean-dry, water, and fat contents) of the flight muscles of the catbird were investigated as a function of the large seasonal changes in body mass which occur in this species. The mass of the pectoralis muscle is highly positively correlated with body mass, leading to an elevation in muscle mass of ∼35% during fall premigratory fattening. The changes in muscle mass are brought about by coordinated variations in all major components of the muscles which were measured. High-oxidative, fast-twitch fibers represent 88% of the total fibers in the pectoralis muscle. The cross-sectional area of the muscle …


Measurement Of Maximum Oxygen Consumption In Guinea Fowl Numida Meleagris Indicates That Birds And Mammals Display A Similar Diversity Of Aerobic Scopes During Running, David J. Ellerby, Maryellen Cleary, Richard L. Marsh, Cindy I. Buchanan Dec 2010

Measurement Of Maximum Oxygen Consumption In Guinea Fowl Numida Meleagris Indicates That Birds And Mammals Display A Similar Diversity Of Aerobic Scopes During Running, David J. Ellerby, Maryellen Cleary, Richard L. Marsh, Cindy I. Buchanan

Richard Marsh

Judgement of exercise performance in birds has been hampered by a paucity of data on maximal aerobic capacity. We measured the maximal rate of oxygen consumption (V̇o₂,max) in running guinea fowl Numida meleagris, a bird that has been used in several previous studies of avian running. Mean V̇o₂,max during level treadmill running was 97.5±3.7 mL O&8322; kg⁻¹ min⁻¹ (mean ± SEM, N=5). V̇o₂,max was on average 6% higher when the birds ran uphill compared with the value during level running (paired t-test, P=0.041, N=5). The mean basal rate of oxygen consumption (V̇o₂,bmr) of the same individuals was 7.9±0.5 mL kg⁻¹ …


Birdstrike Mitigation - Beyond The Airport, Paul Eschenfelder, Russ Defusco Aug 2010

Birdstrike Mitigation - Beyond The Airport, Paul Eschenfelder, Russ Defusco

Paul F. Eschenfelder

No abstract provided.


Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza Jul 2010

Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Michael P Lombardo

Homosexual courtship behavior in non-human animals is well known (Ford and Beach 1980) and occurs in a wide variety of taxa. However, homosexual copulations, especially between males, are less well known. In birds, males mounting other males have been observed in the colonially breeding Cattle Egret (Bubulcus ibis) (Fujioka and Yamagishi 1981) and Common Murre (Uria aalge) (Birkhead et al. 1985, Hatchwell 1988). Neither Fujioka and Yamagishi (1981) nor Birkhead et al. (1985) and Hatchwell (1988) reported whether cloacal contact occurred during their observations of male-male mountings. Here we describe homosexual copulations by male Tree Swallows …


Using Biodiversity Data To Assess Species--Habitat Relationships In Glacier National Park, Montana, Diane M. Debinski, Peter F. Brussard Nov 1994

Using Biodiversity Data To Assess Species--Habitat Relationships In Glacier National Park, Montana, Diane M. Debinski, Peter F. Brussard

Diane M. Debinski

Biodiversity surveys are becoming increasingly popular. However, standard analysis techniques for these data have not yet been developed. This paper explores the use of multivariate ordination techniques for assessing species—habitat relationships using biodiversity data. The research was conducted in Glacier National Park, Montana, and birds and butterflies were chosen as the taxonomic groups of study. Biodiversity assessment sites were established throughout a range of habitats and monitored from 1987 through 1989. Presence/absence sampling over the total number of sampling sites was used to classify species commonness and rarity. Approximately 86% of the historically recorded butterflies and 70% of the historically …


Odor Detection Thresholds In Tree Swallows And Cedar Waxwings, Larry Clark Jan 1991

Odor Detection Thresholds In Tree Swallows And Cedar Waxwings, Larry Clark

Larry Clark

No abstract provided.