Otobius megnini (Acarina: Argasidae) in the Ears of Pronghorn Antelope (Antilocapra americana) in New Mexico

Radiochemical procedures were used to determine strontium-90 distribution and concentrations in dentary bone samples taken from three positions on the mandibles of female pronghorn antelopes (Antilocapra americana americana) collected in October 1964 in the Newell study area, Alberta. No significant differences in pCi of 90Sr per gram of calcium were found between mandible position means, and females in the same age-classes showed no individual variations in 90Sr burdens. The differences in mean 90Sr concentrations between age-classes were highly significant, with the youngest and oldest animals showing the largest and smallest 90Sr burdens, respectively.

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Influence of Range Condition on Pronghorn (Antilocapra americana) and Cattle Diets in Southern New Mexico

Journal of Applied Animal Research ◽

10.1080/09712119.2009.9707021 ◽

2009 ◽

Vol 36 (1) ◽

pp. 13-16

Author(s):

F. Clemente ◽

J. L. Holechek ◽

R. Valdez ◽

G. D. Mendoza

Keyword(s):

New Mexico ◽

Antilocapra Americana ◽

Range Condition

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Threat of predation: do ungulates behave aggressively towards different members of a coyote pack?

Canadian Journal of Zoology ◽

10.1139/z98-232 ◽

1999 ◽

Vol 77 (3) ◽

pp. 499-503 ◽

Cited By ~ 13

Author(s):

Eric M Gese

Keyword(s):

Body Size ◽

Aggressive Behavior ◽

Cervus Elaphus ◽

Yellowstone National Park ◽

National Park ◽

Bison Bison ◽

Antilocapra Americana ◽

Wild Canids ◽

Pronghorn Antelope ◽

Large Groups

Wild ungulates have evolved a variety of antipredator strategies to deter or escape predation by carnivores. Among wild canids, the dominant pair of a pack often initiates attacks upon prey. Previous observations in Yellowstone National Park, Wyoming, showed that the alpha pair in a coyote (Canis latrans) pack most often leads attacks on ungulates during winter. We were interested in determining whether ungulates can distinguish (perhaps by body size or posture) which members of a coyote pack are the alpha individuals, and whether they initiate and direct aggressive behavior towards those members of the pack that pose the greatest threat of predation to themselves and (or) their offspring. During 2507 h of behavioral observations on 54 coyotes between January 1991 and June 1993, we observed 51 interactions between coyotes and adult elk (Cervus elaphus), bison (Bison bison), and pronghorn antelope (Antilocapra americana) in Yellowstone National Park. The interactions analyzed here are those in which the ungulate appeared to initiate aggressive behavior towards the coyote(s) and were not a response to an attack by the predators. We found that aggression by ungulates towards coyotes was highest during the summer months, when calves and fawns were present; female ungulates were more frequently aggressive than males. The frequency of aggression of adult ungulates towards small and large groups of coyotes was equal to the frequency of occurrence of these groups. Ungulates directed aggressive behavior more frequently towards alpha coyotes and were less aggressive towards beta coyotes and pups. Large ungulates, particularly elk and bison, appeared to perceive that alpha coyotes posed a greater threat to themselves and their offspring. The smaller ungulate, the pronghorn antelope, directed aggressive behavior equally towards all coyotes. Adult ungulates were probably responding to the larger body size of the alpha coyotes and the tendency of alpha coyotes to travel at the front of the pack.

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Comparación de dos métodos de liberación del berrendo, Antilocapra americana (Artiodactyla: Antilocapridae) en Coahuila, México

Revista de Biología Tropical ◽

10.15517/rbt.v65i3.29447 ◽

2017 ◽

Vol 65 (3) ◽

pp. 1208

Author(s):

Hugo Sotelo Gallardo ◽

Armando J. Contreras Balderas ◽

Alejandro Espinosa Treviño

Keyword(s):

New Mexico ◽

Mortality Rate ◽

Antilocapra Americana ◽

Mammal Species ◽

High Interest ◽

New Information ◽

Capture Stress ◽

Reintroduction Success ◽

Release Method ◽

Fast Release

The reintroduction of missing mammal species in former habitats has recently been of high interest. In Mexico, there have been several attempts to reintroduce Antilocapra since 1967, but until now none of the trials has been successful. Nowadays, different releasing methods have been practiced for mammal species, including soft and hard release ones. The aim of this study was to provide new information, and to evaluate the success of a recent release. The study was based on the monitoring of 100 individuals (70 females, 30 males) captured in New Mexico, USA, to be released in Maderas del Carmen, Coahuila, Mexico, in two different groups. The first group (fast release) of 45 specimens (20 females, 25 males) was released in the valley at the beginning of March 2009. The second one (soft release), with 55 individuals (50 female, 5 male), was released in March 2010. For both groups, we compared the mortality rate between dispersal and soft-release vs. hard-release methods. Our results showed that the release with adaptation gave highly significant results (χ2= 2, α= 0.05, p= 0.0001)). The comparison of mortality and dispersion among both methods was highly contrasting: with soft-release we obtained 4 % and 13 % of success, against 23 % and 46 %, respectively. Considering these results, we recommend the soft-release method to be used in future reintroduction attempts of Antilocapra, since more than 50 % of specimens from hard-releases died because of capture stress, or were dispersed, and thus reduced the reintroduction success chances.

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