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Mary Meagher

Publications and source records attributed to Mary Meagher.

8 recordsLinked to original sources
USGS2002

On the origin of brucellosis in bison of Yellowstone National Park: a review

Brucellosis caused by Brucella abortus occurs in the free-ranging bison ( Bison bison ) of Yellowstone and Wood Buffalo National Parks and in elk ( Cervus elaphus ) of the Greater Yellowstone Area. As a result of nationwide bovine brucellosis eradication programs, states and provinces proximate to the national parks are considered free of bovine brucellosis. Thus, increased attention has been focused on the wildlife within these areas as potential reservoirs for transmission to cattle. Because the national parks are mandated as natural areas, the question has been raised as to whether Brucella abortus is endogenous or exogenous to bison, particularly for Yellowstone National Park. We synthesized diverse lines of inquiry, including the evolutionary history of both bison and Brucella , wild animals as Brucella hosts, biochemical and genetic information, behavioral characteristics of host and organism, and area history to develop an evaluation of the question for the National Park Service. All lines of inquiry indicated that the organism was introduced to North America with cattle, and that the introduction into the Yellowstone bison probably was directly from cattle shortly before 1917. Fistulous withers of horses was a less likely possibility. Elk on winter feedgrounds south of Yellowstone National Park apparently acquired the disease directly from cattle. Bison presently using Grand Teton National Park probably acquired brucellosis from feedground elk.

Idaho, Montana, Wyoming↗
USGS1999

Yellowstone and the biology of time: Photographs across a century

Established in 1872, Yellowstone National Park is the oldest and one of the largest national parks in the world. In this remarkable book, scientists Mary Meagher and Douglas B. Houston present 100 sets of photographs that compare the Yellowstone of old with the park of today. Most of the photo sets include three pictures-not the usual two-with many of the original views dating back to the 1870s and 1880s. From the same photo points used by early photographers, Meagher and Houston rephotographed the scenes in the 1970s, and then, following the great fires of 1988, again in the 1990s. The result is an illuminating record of Yellowstone’s dynamic ecosystem and its changes over time. Through close analysis of the photos and reference to the vast amount of available data, Meagher and Houston describe changes in vegetation, growth of wildlife populations, the effect of beaver occupancy on wetland areas, and geothermal and elevational shifts. At the same time they point out the extent to which many sites have not changed-despite important switches in park policy and an increase in human activity. Yellowstone National Park has long been the focus of major ecological debates. Should managers allow wildfires to burn? Should the elk and bison populations be controlled? Are too many people visiting the park? Yellowstone And The Biology Of Time offers a wealth of information to help us answer these questions. A visual treasure, this book will be of value to scientists from various disciplines as well as to the many people who care about Yellowstone and other protected wilderness areas around the world.

Yellowstone National Park↗
USGS1994

Bison in the greater Yellowstone

In the Greater Yellowstone Area, free-ranging bison occur in Jackson Hole, Wyoming, and Yellowstone National Park. The Yellowstone population is discussed, with emphasis on changes in numbers from approximately 400 in 1968 to about 3500 now. Major influences for change initially were natural; more recently the winter road system used by snowmobiles appeared to be the dominant factor. The situation is in a state of flux. Interagency planning is in progress to address management alternatives for conflicts outside the park.

Report↗
USGS1992

Chlamydial-caused infectious keratoconjunctivitis in bighorn sheep of Yellowstone National Park

An epizootic of infectious keratoconjuctivitis occurred in bighorn sheep ( Ovis canadensis ) in Yellowstone National Park during the winter of 1981-82. The causative organism was identified as Chlamydia sp. Mortality related to the epizootic was approximately 60% of an estimated 500 bighorn sheep in the northern range population. The infection probably affected all sex and age classes, but field surveys of live animals and mortality suggested that mature rams died disproportionately. Limited field observations the following winter on individuals having both normal and cloudy-appearing eyes suggested that half of the bighorns then present on the core units of winter range had contracted the disease and survived. By 1988, there were about 300 bighorn sheep in the population.

Idaho, Montana, Wyoming↗