Geology topics

John L. Hoogland

Publications and source records attributed to John L. Hoogland.

3 recordsLinked to original sources

USGS2018

Plague in a colony of Gunnison's prairie dogs (Cynomys gunnisoni) despite three years of infusions of burrows with 0.05% deltamethrin to kill fleas

At Valles Caldera National Preserve in New Mexico, US, infusing Gunnison's prairie dog ( Cynomys gunnisoni ) burrows with an insecticide dust containing 0.05% deltamethrin killed fleas which transmit bubonic plague. The reduction in the number of fleas per prairie dog was significant and dramatic immediately after infusions, with a suggestion that the reduction persisted for as long as 12 mo. Despite the lower flea counts, however, a plague epizootic killed >95% of prairie dogs after 3 yr of infusions (once per year). More research is necessary for a better understanding of the efficacy of insecticide dusts at lowering flea counts and protecting prairie dogs from plague.

Journal of Wildlife Diseases↗

USGS2016

Factors that affect parasitism of black-tailed prairie dogs by fleas

Fleas (Insecta: Siphonaptera) are hematophagous ectoparasites that feed on vertebrate hosts. Fleas can reduce the fitness of hosts by interfering with immune responses, disrupting adaptive behaviors, and transmitting pathogens. The negative effects of fleas on hosts are usually most pronounced when fleas attain high densities. In lab studies, fleas desiccate and die under dry conditions, suggesting that populations of fleas will tend to decline when precipitation is scarce under natural conditions. To test this hypothesis, we compared precipitation vs. parasitism of black-tailed prairie dogs ( Cynomys ludovicianus ) by fleas at a single colony during May and June of 13 consecutive years (1976–1988) at Wind Cave National Park, South Dakota, USA. The number of fleas on prairie dogs decreased with increasing precipitation during both the prior growing season (April through August of the prior year) and the just-completed winter–spring (January through April of current year). Due to the reduction in available moisture and palatable forage in dry years, herbivorous prairie dogs might have been food-limited, with weakened behavioral and immunological defenses against fleas. In support of this hypothesis, adult prairie dogs of low mass harbored more fleas than heavier adults. Our results have implications for the spread of plague, an introduced bacterial disease, transmitted by fleas, that devastates prairie dog colonies and, in doing so, can transform grassland ecosystems.

Ecosphere↗

USGS2012

Conflicting research on the demography, ecology, and social behavior of Gunnison's prairie dogs ( Cynomys gunnisoni )

Gunnison's prairie dogs ( Cynomys gunnisoni ) are rare, diurnal, colonial, burrowing, ground-dwelling squirrels. Studies of marked individuals living under natural conditions in the 1970s, 1980s, and 1990s showed that males are heavier than females throughout the year; that adult females living in the same territory are consistently close kin; and that females usually mate with the sexually mature male(s) living in the home territory. Research from 2007 through 2010 challenges all 3 of these findings. Here we discuss how different methods might have led to the discrepancies.

Journal of Mammalogy↗