Vernon C. Bleich

There is little question that the distribution and numbers of large mammals have been altered by human activities. In North America, native ungulates have declined substantially since the mid-1800s. There is no baseline, however, against which to measure the magnitude of changes aside from anecdotal accounts or published information derived from a single location at a single point in time and extrapolated to derive a continent-wide population estimate. One example is bighorn sheep (Ovis canadensis), which were estimated to number from 1.5 to 2.0 million individuals in 1850. The literature is replete with references to those numbers, yet the derivation of that ‘estimate’ has not been formally questioned; bighorn sheep, which are endemic to North America, currently number approximately 85,000 individuals. We combined basic math and logic to develop a simple model of population density at differing scales and examined results reductio ad absurdum to question the estimate of 1.5 million bighorn sheep and the magnitude of the hypothesized decline that followed. We evaluated the plausibility of bighorn sheep population densities that must have existed at four spatial scales if there were ≥1.5 million individuals and argue that such numbers likely never existed. Continued use of 1.5 million bighorn sheep as a baseline against which to assess the magnitude of anthropogenic impacts is unwise, inappropriate, and apt to become problematic in the context of the conservation of habitat, populations, or restoration to historical ranges. Credibility matters in science, management, and conservation.

Unmanned aerial vehicles (UAV), often referred to as unmanned aerial systems (UAS) or drones, are experiencing increasing use by wildlife researchers and for a variety of purposes. When equipped with one or more of the various sensors currently available, these remotely operated platforms are being used to conduct aerial surveys of large mammals occupying a diversity of ecosystems, but more so for species that occupy terrain that is neither as rugged nor topographically extreme as that occupied by mountain sheep. Despite some of the potential advantages offered by this technology, UAVs have not been used extensively to survey populations of mountain sheep. In this paper, we provide some background information regarding the (1) utility of these platforms to survey mountain sheep; (2) types of unmanned aerial vehicles currently available; (3) types and limitations of currently available sensors; (4) factors that complicate use of these technologies specifically for surveys of mountain sheep populations; and (5) some additional suggestions, including ways to mitigate some of those complications. For reasons enumerated herein, these aerial platforms and associated sensors currently are used sparingly in mountain sheep habitat, but we predict use will increase substantially as a result of technological advances and the human safety advantages associated with these devices.

Minerals are important nutrients and are essential components of the diets of animals. Nutritional requirements or minimum concentrations of minerals for nutritional health are largely unknown for the majority of large, free-ranging herbivores. We investigated concentrations of 9 trace minerals in mule deer (Odocoileus hemionus) inhabiting 3 distinct geographic areas—Cima Dome, New York Mountains, and the Mid Hills—in the eastern Mojave Desert, San Bernardino Co., California from 2008 to 2016. These areas differed in vegetative communities, topography, water availability, and fire histories. Telemetered mule deer demonstrated high fidelity to each of these areas, and movement by those individuals between study areas was not detected. During our investigation, overall differences occurred in mean concentrations of magnesium (P < 0.001), calcium (P = 0.022), phosphorus (P = 0.023), potassium (P = 0.042), and selenium (P < 0.001) among the 3 geographic areas. Among years, differences occurred in concentrations of the trace elements investigated in the New York Mountains with the exceptions of magnesium and potassium; at Cima Dome with the exceptions of iron, sodium, potassium, and selenium; and in the Mid Hills with the exceptions of magnesium and zinc. A positive upward trend existed between selenium concentration in the New York Mountains and the year of sample collection (P < 0.05), and a similar—albeit not significant—upward trend was discernible in the Mid Hills, but no such relationship was apparent at Cima Dome. These results emphasize the importance of investigating micronutrient status of mule deer on a local scale and temporally and add to the sparse information available on trace mineral concentrations in mule deer. Despite limited samples (≤165), we make available for the first time reference values for mule deer inhabiting the Mojave Desert, to serve as a baseline against which to measure responses to future environmental perturbations or for comparison with deer occupying other disparate ecosystems, and further contribute to the derivation of reference values for mule deer in general.

BOOK REVIEW Bryan Hockett and Eric Dillingham (with contributions by Clifford Alpheus Shaw and Mark O’Brien). 2023. Texas A&M University Press, College Station, TX, USA. 160 pages (hardcover). $85.00. ISBN: 978-1-64843-108-1 www.doi.org/10.51492/cfwj.111.6 The authors of this work, Bryan Hockett and Eric Dillingham, are retired U.S. Government scientists with may years of experience serving the U.S.…

Earth has >8 billion people. Scholarly publications number nearly 7 million annually with >1 million in the life and biomedical sciences, and ≥52 professional journals specializing in conservation, ecology, or related disciplines. The challenges of applying ecological data to conservation and wildlife management can easily become overwhelming. Herein we offer reflective perspectives about the changing face of applied knowledge and engagement from our personal employment histories as ecologists working in agency, university, and non‐governmental organization (NGO) biologist positions. We suggest natural history will always be nature's glue, but knowledge steeped mostly in muddy boots and field biology are no longer the soup du jour of our profession. In many ways, new technologies have changed data collection and the scientific questions asked. Arguably, such change is not welcomed by all, but a change in overlap across decades is needed to sustain and improve upon how the planet's biological diversity can coexist with increasingly difficult human conditions. Given that 80% of the people in the United States live in urban areas, with similar numbers internationally, a future possibility may be an even greater divide between wild nature, ecological services, and enjoyment in the field. This is disturbing. Despite fundamental scientific insights that help understand critical components of the natural world, once society loses touch with nature, what will remain?

Coloration is among the characteristics noted first by observers, and color has a strong influence on how animals are perceived. Abnormal coloration has been reported in a variety of taxa, but less frequently among mammals than other classes of vertebrates. Chromatic disorders occurring among Mammalia include albinism, leucism, piebaldism, melanism, xanthism, erythrism, and isabellinism, but only leucism, melanism, and piebaldism have been confirmed in bighorn sheep (Ovis canadensis); ‘albinism’ has been reported in that taxon, but in the absence confirmatory evidence. Bighorn sheep possessing white, or extremely light-colored pelage, have been described in the literature as albinistic, leucistic, or simply as ‘white’. Isabellinism is a genetic anomaly that manifests as sandy- or cream-colored pelage that appears washed-out and otherwise would be dark in color. Some reports of albinistic, leucistic, or ‘white’ bighorn sheep, however, likely represent animals that were of isabelline coloration. This is the first paper to ascribe this unusual color morph to bighorn sheep, and I (1) provide photographs, references, and other evidence of what appears to be isabellinism in that species; (2) explain why those observing ‘white’ bighorn sheep likely have failed to recognize isabelline coloration; (3) discuss the evolutionary consequences of that anomalous condition in terms of fitness and future adaptation; (4) emphasize the role of what may appear to be meaningless observations in terms of their potential ramifications for understanding or explaining phenomena that heretofore have not been fully explored; and (5) encourage readers to recognize that natural history observations have potentially important implications for the interpretation of adaptation and natural selection, and can provide new insight into prior conclusions or future applications.

BOOK REVIEW Maurice Hornocker (with David Johnson). 2023. Lyons Press, Essex, CT, USA. 295 pages (hardcover). $29.95. ISBN: 978-1-4930-7329-0 www.doi.org/10.51495/cfwj.109.20 My memories are remnants of what field research was, but may never be again. Simplicity and intuition have been relegated if not lost. Feet on the ground have been replaced by the latest technology. Yes,…

BOOK REVIEW Jerry Emory. 2023. University of Chicago Press, Chicago, Illinois, USA. 254 pages (hard cover). $28.00. ISBN 978-0-226-82494-9. www.doi.org/10.51495/cfwj.109.15 For many years I had heard references to the George Wright Society and the George Wright Forum. When this book was published, I seized upon a chance to learn a bit about just what both…

Estimates of body condition or body composition are useful metrics, and consistency among results determined by independent investigators enhances their utility. If concordant, albeit subjective, assessments of body condition can be achieved by personnel possessing differing levels of expertise, there are important implications for generating useful information that otherwise may not be obtained by investigators facing logistic or economic constraints, or difficult field conditions. We used a serendipitous opportunity to explore level of agreement among personnel with disparate levels of anatomical knowledge and familiarity with palpation to index body condition of 55 bighorn sheep ( Ovis canadensis ). Our preliminary results—albeit affected by sample size—suggested the investigators interpreted and applied scoring criteria similarly, despite their differing backgrounds. Given the potential to gain meaningful information on body condition that otherwise may not be attainable, we encourage further evaluation of concordance among independent investigators whenever body condition of bighorn sheep can be rated independently by >1 individual and, further, that the information be shared widely.