Publications
Filter Total Items: 2085
Influence of habitat, sex, age, and drought on the diet of Townsend's ground squirrels Influence of habitat, sex, age, and drought on the diet of Townsend's ground squirrels
We assayed diets of Townsend's ground squirrels (Spermophilus townsendii) in a semi-arid shrub steppe in Idaho by analyzing 1,432 fecal samples during 1991–1994. Dietary composition differed between adults and juveniles but not between males and females. Sand-berg's bluegrass (Poa secunda), a perennial bunchgrass, was the most common item in diets. Diets varied among habitats that...
Authors
Beatrice Van Horne, Robert L. Schooley, Peter B. Sharpe
Organochlorine pesticides, PCBs, and mercury in hawk, falcon, eagle, and owl eggs from the Lipetsk, Voronezh, Novgorod and Saratov regions, Russia, 1992-1993 Organochlorine pesticides, PCBs, and mercury in hawk, falcon, eagle, and owl eggs from the Lipetsk, Voronezh, Novgorod and Saratov regions, Russia, 1992-1993
Fifty-two eggs (one per nest) of 12 species of raptors were collected in 1992-93 for contaminant analysis in three southern European locations in Russia. One Peregrine Falcon (Falco peregrinus) egg was also collected farther northwest in the Novgorod region. A high DDE concentration (27.3 ppm, wet weight [w/w]) in the Peregrine Falcon egg raised concern for the species in European Russia...
Authors
Charles J. Henny, S.A. Ganusevich, F.P. Ward, T.R. Schwartz, A.L. Mischenko, V.N. Moseikin, V.S. Sarychev
Effects of pesticides on Canada Geese Effects of pesticides on Canada Geese
This paper summarizes published and unpublished sources relating to exposure of Canada geese (Branta canadensis) to pesticides, emphasizing documented episodes of poisoning by organochlorine (OC), organophosphorus (OP), and carbamate compounds. Canada geese accumulate the lipid-soluble OC compounds, although they have a lower potential for biomagnification of these pesticides than...
Authors
L. J. Blus
Diet and morphology of extant and recently extinct northern bears Diet and morphology of extant and recently extinct northern bears
I examined the relationship of diets to skull morphology of extant northern bears and used this information to speculate on diets of the recently extinct cave (Ursus spelaeus) and short-faced (Arctodus simus) bears. Analyses relied upon published skull measurements and food habits of Asiatic (U. thibetanus) and American (U. americanus) black bears, polar bears (U. maritimus), various...
Authors
David J. Mattson
Large-scale fire disturbance: From concepts to models Large-scale fire disturbance: From concepts to models
No abstract available.
Authors
D. L. Peterson
Stenocybe fragmenta, a new species of Mycocaliciaceae with fragmenting spores Stenocybe fragmenta, a new species of Mycocaliciaceae with fragmenting spores
The new species Stenocybe fragmenta (Ascomycota, Mycocaliciaceae) is described from western North America. The species was collected from twigs of Cercocarpus montanus and Rhamnus purshiana. Stenocybe fragmenta is characterized by 5–7 septate, 18–30 μm long ascospores that fragment at maturity. This is the first report of spore fragmentation among the Mycocaliciaceae.
Authors
E.B. Peterson, Jouko Rikkinen
Vulnerability of desert biological soil crusts to wind erosion: The influences of crust development, soil texture, and disturbance Vulnerability of desert biological soil crusts to wind erosion: The influences of crust development, soil texture, and disturbance
Biological soil crusts, consisting of cyanobacteria, green algae, lichens, and mosses, are important in stabilizing soils in semi-arid and arid lands. Integrity of these crusts is compromised by compressional disturbances such as foot, vehicle, or livestock traffic. Using a portable wind tunnel, we found threshold friction velocities (TFVs) of undisturbed crusts well above wind forces...
Authors
Jayne Belnap, Dale A. Gillette
Age determination in turtles: Evidence of annual deposition of scute rings Age determination in turtles: Evidence of annual deposition of scute rings
No abstract available.
Authors
David J. Germano, R. Bruce Bury
Demographic and growth responses of a guerrilla and a phalanx perennial grass in competitive mixtures Demographic and growth responses of a guerrilla and a phalanx perennial grass in competitive mixtures
The advantages of guerrilla and phalanx growth for the guerrilla Elymus lanceolatus ssp. lanceolatus and phalanx E. l. ssp. wawawaiensis were evaluated over 2 years in two taxon mixtures with a range of densities of each subspecies and under two levels of watering. Ramet numbers and biomass of the guerrilla subspecies were higher than those of the phalanx grass in the first year but in...
Authors
L. David Humphrey, David A. Pyke
Impact of alternative regeneration methods on genetic diversity in coastal Douglas-fir Impact of alternative regeneration methods on genetic diversity in coastal Douglas-fir
Genetic implications of natural and artificial regeneration following three regeneration methods (group selection, shelterwood, and clearcut) were investigated in coastal Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) using genetic markers (17 allozyme loci). In general, harvesting followed by either natural or artificial regeneration resulted in offspring populations...
Authors
W.T. Adams, J. Zuo, J.Y. Shimizu, J. C. Tappeiner
Spatial distribution of breeding passerine bird habitats in a shrubsteppe region of southwestern Idaho Spatial distribution of breeding passerine bird habitats in a shrubsteppe region of southwestern Idaho
A paper describing the similarities and differences between trichomoniasis and pox infection. The need for laboratory diagnosis to differentiate between them is indicated.
Authors
Steven T. Knick, J.T. Rotenberry