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Zoology

2010

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Articles 1 - 30 of 183

Full-Text Articles in Life Sciences

Sensitivity And Specificity Of A Nested Polymerase Chain Reaction For Detection Of Lentivirus Infection In Lions (Panthera Leo), H Adams, M Van Vuuren, Stephen Kania, A Bosman, D Keet, J New, Melissa Kennedy Mar 2012

Sensitivity And Specificity Of A Nested Polymerase Chain Reaction For Detection Of Lentivirus Infection In Lions (Panthera Leo), H Adams, M Van Vuuren, Stephen Kania, A Bosman, D Keet, J New, Melissa Kennedy

Stephen A Kania

Feline immunodeficiency virus (FIV) is a lentivirus in the Retroviridae family that causes lifelong infection in domestic cats. The lentivirus of African lions (Panthera leo), referred to as FIVple, is endemic in certain lion populations in eastern and southern Africa. Lentivirus infection leads to immunologic dysfunction and immunosuppressive disease in domestic cats; however, little is known about the pathogenic effects of infection in lions, nor about the epidemiologic impact on free-ranging and captive populations. Whole blood and serum samples were collected opportunistically from free-ranging lions in Kruger National Park, Republic of South Africa (RSA). Whole blood and serum samples were ...


Development Of Temperature Regulation In Nestling Tree Swallows, Richard Marsh Dec 2010

Development Of Temperature Regulation In Nestling Tree Swallows, Richard Marsh

Richard Marsh

No abstract provided.


Adaptations Of The Gray Catbird Dumetella Carolinensis To Long Distance Migration: Energy Stores And Substrate Concentrations In Plasma, Richard Marsh Dec 2010

Adaptations Of The Gray Catbird Dumetella Carolinensis To Long Distance Migration: Energy Stores And Substrate Concentrations In Plasma, Richard Marsh

Richard Marsh

The major body components (water, lean dry, and fat) were measured in the carcasses of Gray Catbirds from which the flight muscles had been removed. Birds were collected from May through October near Ann Arbor, Michigan and during September and October near Gainesville, Florida. Additionally, the glycogen content of muscle and liver and the concentrations of glucose and triglycerides in plasma were determined in catbirds sampled during fall migration in Florida. Catbirds attained maximum body masses of ∼50 g in Florida, largely due to the addition of fat. Relatively lean birds (∼3-4% body fat) in spring through fall weighed approximately ...


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 ...


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 ...


Seasonal And Geographic Variation Of Cold Resistance In House Finches Carpodacus Mexicanus, William Dawson, Richard Marsh, William Buttemer, Cynthia Carey Dec 2010

Seasonal And Geographic Variation Of Cold Resistance In House Finches Carpodacus Mexicanus, William Dawson, Richard Marsh, William Buttemer, Cynthia Carey

Richard Marsh

The house finch (Carpodacus mexicanus) is resident in tropical and subtropical regions as well as in localities having relatively severe winters. The extent of its winter acclimatization was assessed in freshly captured individuals of this species from southern California and Colorado. In severe cold stress tests involving exposure to Tₐ < −60 C, the former did not remain homeothermic any longer in winter than in late spring, whereas the Colorado birds did (8.8 vs. 97.5 min; P < .001). The capacity for winter acclimatization evident in these Colorado individuals was correlated with modest winter fattening, a response lacking in those ...


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 temperature ...


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 ...


The Enzymatic Basis Of High Metabolic Rates In Calling Frogs, Theodore L. Taigen, Kentwood D. Wells, Richard L. Marsh Dec 2010

The Enzymatic Basis Of High Metabolic Rates In Calling Frogs, Theodore L. Taigen, Kentwood D. Wells, Richard L. Marsh

Richard Marsh

Oxygen consumption by male spring peepers (Hyla crucifer) increased linearly with calling rate, reaching peak values of 1.5−1.7 ml O₂/(g⋅h) at the highest calling rates. The intercept of the regression line describing the relationship between metabolism and calling rate does not differ significantly from daytime resting metabolism (0.11 ml O₂/[g⋅h]). Metabolic rate during vigorous locomotor exercise at the same temperature (19 C) was only 1.1 ml O₂/(g⋅h). We measured activities of mitochondrial enzymes in the trunk muscles (internal and external obliques) involved in sound production and in mixed hind ...


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 ...


Brown-Headed Cowbird Parasitism On Endangered Species: Relationships With Neighboring Avian Species, Shannon L. Farrell, Michael L. Morrison, R. Neal Wilkins, R. Douglas Slack, Andrew J. Campomizzi Dec 2010

Brown-Headed Cowbird Parasitism On Endangered Species: Relationships With Neighboring Avian Species, Shannon L. Farrell, Michael L. Morrison, R. Neal Wilkins, R. Douglas Slack, Andrew J. Campomizzi

Western North American Naturalist

Loss of reproductive productivity in hosts of the Brown-headed Cowbird (Molothrus ater), a nest parasite, may limit the success of conservation and recovery efforts that focus on restoring avian habitat. We investigated the relationships between parasitism frequency of 2 vireos—the endangered Black-capped Vireo (Vireo atricapillus) and the White-eyed Vireo (Vireo griseus)—and characteristics of the neighboring avian assemblage. Our objective was to identify assemblage characteristics that are useful for predicting parasitism frequency. We hypothesized that parasitism frequency of the vireos would decrease with increasing alternate host abundance and increase with increasing abundance of cowbirds. All Black-capped Vireo nests (n ...


Rediscovery Of The Neotoma Population On Datil [Turner] Island, Sonora, México, Sergio Ticul Álvarez-Castañeda, Anahid Gutierrez, Mayra De La Paz Dec 2010

Rediscovery Of The Neotoma Population On Datil [Turner] Island, Sonora, México, Sergio Ticul Álvarez-Castañeda, Anahid Gutierrez, Mayra De La Paz

Western North American Naturalist

On Datil [Turner] Island in the Gulf of California, we rediscovered a population ofNeotoma varia, previously thought to be extinct. We captured 5 specimens: 1 was kept as a voucher, and 4 were examined and released. Analysis of previous surveys indicates that N. varia is not common on the island and occupies a very restricted range.


Recolectamos especímenes de Neotoma varia de la Isla Dátil en el Golfo de California, una población anteriormente considerada ya extinta. De los cinco especímenes que recolectamos, cuatro se pusieron en libertad. El análisis de muestreos previos indica que N. varia no es común ...


Trapping Mammals In A Cautious World: The Effect Of Disinfectants On Trap Success, J. A. Wilson, K. E. Mabry Dec 2010

Trapping Mammals In A Cautious World: The Effect Of Disinfectants On Trap Success, J. A. Wilson, K. E. Mabry

Western North American Naturalist

Disinfecting traps that have captured small mammals is one recommendation for preventing occurrence of hantavirus infection; however, the potential effects of disinfection on small mammal trappability have not been investigated thoroughly. We conducted an experiment to compare the effects of 2 disinfectants (Lysol® and household bleach) on the trappability of 4 small mammal species (Peromyscus maniculatus, Neotamias spp., and Spermophilus lateralis). We established triplicate trap grids in 2 forest types (red fir and mixed conifer), each consisting of a 6 × 6 array of Sherman live-traps placed at 10-m intervals. Traps were given 1 of 3 treatments: control (water), Lysol, or ...


Diversity, Phenology, And Elevational Distribution Of Ephemeroptera, Plecoptera, And Trichoptera In American Fork Canyon, Utah, Sarah Walker Judson, C. Riley Nelson Dec 2010

Diversity, Phenology, And Elevational Distribution Of Ephemeroptera, Plecoptera, And Trichoptera In American Fork Canyon, Utah, Sarah Walker Judson, C. Riley Nelson

Western North American Naturalist

Although the aquatic insect fauna of Utah and their associated adult forms are well documented taxonomically and biogeographically, little is known about seasonal and elevational patterns of aquatic insect diversity in individual Wasatch streams. We selected the American Fork River, a relatively pristine stream with little anthropogenic disturbance, as our target stream to investigate elevational distribution and seasonal phenology of adult forms of Ephemeroptera, Plecoptera, and Trichoptera (EPT). From April to October in 2003 through 2005, a total of 71 adult forms of EPT species were documented along the American Fork River. No single sampling period captured more than 30 ...


The Banner-Tailed Kangaroo Rat, Dipodomys Spectabilis (Rodentia: Heteromyidae), In Utah, George V. Oliver, Anthony L. Wright Dec 2010

The Banner-Tailed Kangaroo Rat, Dipodomys Spectabilis (Rodentia: Heteromyidae), In Utah, George V. Oliver, Anthony L. Wright

Western North American Naturalist

We report the discovery in Utah of Dipodomys spectabilis, a species previously unknown to occur in the state. We searched for D. spectabilis in extreme southeastern Utah, south of the San Juan River, and were successful in finding mounds and burrows characteristic of the species and in capturing one individual. This is the northernmost record for D. spectabilis and extends its known range ~84 km northwest of the nearest previously reported locality (Fruitland, San Juan County, New Mexico). A flea, Meringis rectus, collected from D. spectabilis, is also the first record of its species in Utah.


Reportamos el descubrimiento en ...


Note On Occurrence Of Mymaromella Pala Huber And Gibson (Hymenoptera: Mymarommatidae) In Montana: A New State Record, Timothy D. Hatten, Norm Merz, James B. 'Ding' Johnson, Chris Looney, Travis Ulrich, Scott Soults, Roland Capilo, Dwight Bergerone, Paul Anders, Philip Tanimoto, Bahman Shafii Dec 2010

Note On Occurrence Of Mymaromella Pala Huber And Gibson (Hymenoptera: Mymarommatidae) In Montana: A New State Record, Timothy D. Hatten, Norm Merz, James B. 'Ding' Johnson, Chris Looney, Travis Ulrich, Scott Soults, Roland Capilo, Dwight Bergerone, Paul Anders, Philip Tanimoto, Bahman Shafii

Western North American Naturalist

The parasitic wasp Mymaromella pala Huber and Gibson (Hymenoptera: Mymarommatidae) was collected at 4 sites within a canyon reach of the Kootenai River in Lincoln County, Montana. This minute species has only recently been described, but it appears to have a large distribution throughout the United States and to be associated with upland and riparian forests.


La avispa parasitaria Mymaromella pala Huber y Gibson (Hymenoptera: Mymarommatidae) se recolectó en cuatro sitios a lo largo de un cañón del Río Kootenai en Lincoln Co., MT. Hace poco que se describió esta especie diminuta, pero parece tener una distribución extensa en los ...


Front Matter, Vol. 70 No. 4 Dec 2010

Front Matter, Vol. 70 No. 4

Western North American Naturalist

No abstract provided.


End Matter, Vol. 70 No. 4 Dec 2010

End Matter, Vol. 70 No. 4

Western North American Naturalist

No abstract provided.


Retrospective Evaluation Of The Effects Of Human Disturbance And Goldfish Introduction On Endangered Pahrump Poolfish, James E. Deacon, Joshua E. Williams Dec 2010

Retrospective Evaluation Of The Effects Of Human Disturbance And Goldfish Introduction On Endangered Pahrump Poolfish, James E. Deacon, Joshua E. Williams

Western North American Naturalist

Life history data for Pahrump poolfish (Empetrichthys latos latos) collected from 1937 to 1975 were organized and analyzed to improve our understanding of changes caused by human habitat disruption and introduced goldfish (Carassius auratus) at Manse Spring, Nevada. Pahrump poolfish twice demonstrated their ability to recover numerically from a population crash. The first crash followed a November 1961 introduction of a few goldfish and subsequent removal of vegetation by local ranch children intent on turning Manse Spring into a swimming hole. The second crash followed another major habitat disturbance resulting from an unsuccessful attempt to eradicate goldfish in July 1967 ...


European Earwig, Forficula Auricularia L. (Dermaptera: Forficulidae), At The Hanford Reach National Monument, Washington State, Richard S. Zack, Dennis Strenge, Peter J. Landolt, Chris Looney Dec 2010

European Earwig, Forficula Auricularia L. (Dermaptera: Forficulidae), At The Hanford Reach National Monument, Washington State, Richard S. Zack, Dennis Strenge, Peter J. Landolt, Chris Looney

Western North American Naturalist

The European earwig, Forficula auricularia L., was surveyed using pitfall traps at 3 sites at the Hanford Reach National Monument in south central Washington State. Pitfall traps were collected weekly from April 2002 through April 2003. The earwig was consistently taken during all months of the year at a disturbed, weedy site along the Columbia River (White Bluffs Ferry site) but was rare or not collected in 2 less-disturbed shrubsteppe habitats. Highest numbers occurred during April–May, when immatures accounted for the majority of the catch; immatures reached the adult stage during mid-July, and the species is univoltine at the ...


Considerations For Wood River Sculpin Conservation: Historical Occurrence And Sampling Efficiency, Donald W. Zaroban Dec 2010

Considerations For Wood River Sculpin Conservation: Historical Occurrence And Sampling Efficiency, Donald W. Zaroban

Western North American Naturalist

Records of Wood River sculpin (Cottus leiopomus) from 1893 to 2003 were examined and new data were gathered in 2004 and 2006 to estimate the species’ historical range and to search for evidence of changes in its occurrence. Detections of Wood River sculpin were reported in 49 subwatersheds, primarily in the Idaho Batholith ecoregion. The remainder of the Wood River basin was classified as either potential historic range or unknown. Mark-recapture sampling was conducted to estimate the efficiency of electrofishing as a method to detect this sculpin. Sampling efficiency was calculated for 1 upstream pass and 1, 2, and 3 ...


Desiccation Sensitivity And Heat Tolerance Of Prunus Ilicifolia Seeds Dispersed By American Black Bears (Ursus Americanus), Mark Borchert, Claudia M. Tyler Dec 2010

Desiccation Sensitivity And Heat Tolerance Of Prunus Ilicifolia Seeds Dispersed By American Black Bears (Ursus Americanus), Mark Borchert, Claudia M. Tyler

Western North American Naturalist

Carnivore consumption of fruit is a principle means by which many fleshy-fruited plant species achieve long-distance seed dispersal. We examined carnivore dispersal of hollyleaf cherry (Prunus ilicifolia) seeds, specifically assessing the survival, desiccation sensitivity, and germination of seeds found in bear scats. Studies were conducted both in the laboratory and in 2 burn areas in Los Padres National Forest, California. Bear scats containing P. ilicifolia seeds were collected in burned and unburned chaparral. We counted seeds in each scat and noted whether endocarps had tooth punctures or rattled audibly when shaken. For comparative germination trials, we also collected fruits and ...


Mate Sampling In A Natural Population Of Pecos Gambusia, Gambusia Nobilis, John K. Leiser, Kimberly Little, Murray Itzkowitz Dec 2010

Mate Sampling In A Natural Population Of Pecos Gambusia, Gambusia Nobilis, John K. Leiser, Kimberly Little, Murray Itzkowitz

Western North American Naturalist

Much research has been conducted on the mating systems of poeciliid fish in aquaria; however, there are fewer studies that examine mate sampling of these fish in the wild. In general, male poeciliids are characterized as being unselective in their mate choices and will attempt to copulate with seemingly all available females. Females are selective, copulate infrequently, and are often pursued by “ardent” males who may force copulations. To avoid male harassment, females in aquaria will often shelter from males among other females in shoals. Here, we examined the mate-sampling behaviors of male and female Pecos gambusia Gambusia nobilis by ...


Fecal Pellets Of American Pikas (Ochotona Princeps) Provide A Crude Chronometer For Dating Patch Occupancy, Lyle B. Nichols Dec 2010

Fecal Pellets Of American Pikas (Ochotona Princeps) Provide A Crude Chronometer For Dating Patch Occupancy, Lyle B. Nichols

Western North American Naturalist

American pikas (Ochotona princeps) seem to be especially vulnerable to climate change, with recent extinctions of pika populations being attributed to global warming. Incomplete historical location records are currently used to examine changes in pika distributions. A method of determining recent pika distributions in the absence of historical records is needed. Here I report on changes over time of known-age pika fecal pellets up to 36 years old. Predictable changes in diameter, internal consistency, and color of pellets provide a method to approximate the dates of last occupation in patches where pikas have been extirpated.


La pika Americana (Ochotona princeps ...


Distribution Of A Unique Limpet (Gastropoda: Ancylidae) In The Colorado River Drainage Basin, Western North America, Peter Hovingh Dec 2010

Distribution Of A Unique Limpet (Gastropoda: Ancylidae) In The Colorado River Drainage Basin, Western North America, Peter Hovingh

Western North American Naturalist

I determined the distribution of limpets (Gastropoda: Ancylidae: Ferrissia) in the Colorado River and Rio Grande basins by handpicking specimens from the undersides of rocks and vegetation at 16 sites from a total of 495 surveyed sites in Colorado, Utah, New Mexico, and Arizona. Shell morphology, including morphometrics, was compared to species holotype descriptions and museum lots. Ferrissia rivularis occurred in the upper Colorado, Gunnison, and San Juan rivers, and in the upper Rio Grande basin.Ferrissia walkeri, hereafter called the Walker morph, occurred only in the Gila River basin of Arizona and New Mexico. I reviewed the problems of ...


Rock Outcrops Harbor Native Perennials In Type-Converted Coastal Scrub, Robert J. Steers Dec 2010

Rock Outcrops Harbor Native Perennials In Type-Converted Coastal Scrub, Robert J. Steers

Western North American Naturalist

Type-conversion of coastal scrub to exotic annual grassland has been extensive in certain parts of southern California, especially in drier inland locales. Field observations suggest that rock outcrops harbor native perennials associated with coastal scrub vegetation after conversion to exotic annual grassland has occurred. Surveys were conducted to test this observation. In addition, measures of fossorial mammal disturbance, soil depth, exotic annual plant abundance, and soil moisture were collected and used to infer potential mechanisms that may influence patterns of native and exotic vegetation. Results showed that larger outcrops are associated with more native perennial species than smaller outcrops, consistent ...


Nonnative Phragmites Australis Invasion Into Utah Wetlands, Andrew Kulmatiski, Karen H. Beard, Laura A. Meyerson, Jacob R. Gibson, Karen E. Mock Dec 2010

Nonnative Phragmites Australis Invasion Into Utah Wetlands, Andrew Kulmatiski, Karen H. Beard, Laura A. Meyerson, Jacob R. Gibson, Karen E. Mock

Western North American Naturalist

Phragmites australis (Cav.) Trin. ex Steud. (common reed), already one of the world’s most widespread plant species, has realized rapid range expansion in coastal wetlands of North America in the past century, but little is known about P. australis range expansion in inland wetland systems. We used genetic analyses, aerial photographs, field surveys, and a greenhouse experiment to study the extent and mechanism of nonnative P. australis invasion of Utah wetlands. We collected and genetically analyzed 39 herbarium samples across the state and 225 present-day samples from northern Utah’s major wetland complexes. All samples collected before 1993 and ...


The Stream–Lake Ecotone: Potential Habitat For Juvenile Endangered June Suckers (Chasmistes Liorus), Russell B. Rader, Mark C. Belk, Rollin Hotchkiss, Jaron Brown Dec 2010

The Stream–Lake Ecotone: Potential Habitat For Juvenile Endangered June Suckers (Chasmistes Liorus), Russell B. Rader, Mark C. Belk, Rollin Hotchkiss, Jaron Brown

Western North American Naturalist

Potamodromous fish are poorly studied even though they are threatened often by human activities. The June sucker (Chasmistes liorus) is an endangered potamodromous species endemic to Utah Lake. Larval June suckers have not been collected from Utah Lake for at least 3 decades. Recruitment appears to be limited by low temperatures and scarce food, resulting in mass starvation of larval June suckers in the stream environment. We compared water temperature, zooplankton food availability, and small fish abundance in the stream and in 3 habitats along the stream–lake ecotone (dense emergent vegetation, sparse emergent vegetation, and open lake) to test ...


Antipredatory Defense Of Neonatal Pronghorn (Antilocapra Americana) By Yearling Male Pronghorn In Southwestern South Dakota, Christopher N. Jacques, Jonathan A. Jenks Dec 2010

Antipredatory Defense Of Neonatal Pronghorn (Antilocapra Americana) By Yearling Male Pronghorn In Southwestern South Dakota, Christopher N. Jacques, Jonathan A. Jenks

Western North American Naturalist

Antipredatory defense of pronghorn (Antilocapra americana) neonates (≤1 month old) by adult females (>18 months old) is well documented throughout the geographic range of this species. However, reports of male pronghorn defending neonates against predators are limited to a single study in northwestern Wyoming where occurrences were documented of adult males assisting female pronghorn in defending neonates against coyotes (Canis latrans). To our knowledge, defense of neonatal pronghorn by yearling males (12–18 months old) has not been reported previously for this species. We report occurrences of antipredatory defense of neonatal pronghorn by yearling males in southwestern South Dakota.


La ...


Pathology Of An Unusual Lumbar Condition In A Young Black Bear (Ursus Americanus) From The Big Bend Region Of Trans-Pecos Texas, Frederick B. Stangl Jr., Dana R. Mills, Michael W. Haiduk Dec 2010

Pathology Of An Unusual Lumbar Condition In A Young Black Bear (Ursus Americanus) From The Big Bend Region Of Trans-Pecos Texas, Frederick B. Stangl Jr., Dana R. Mills, Michael W. Haiduk

Western North American Naturalist

The skeleton of a young American black bear (Ursus americanus) possessing asymmetrical distortions of the 5 caudalmost lumbar neural spines was recovered from west Texas. We attribute this abnormality, presumed to be congenital, to the absence or atrophy of the right multifidus muscle straddling L3 and to the series of compensatory muscle adjustments required to maintain spinal alignment. This finding may have important management implications for black bears in Texas, given the possibility that our specimen originates from a partially isolated population.


El esqueleto de un oso negro juvenil (Ursus americanus) con distorsiones asimétricas de las cinco espinas neurales lumbares ...