Ryan Long, Ph.D.
Associate Professor of Wildlife Sciences
- Ph.D., Biological Sciences, Idaho State University, May 2013, Minor in Biology Education
- M.S., Wildlife Resources, University of Idaho, May 2007
- B.S., Wildlife Biology, University of Alaska Fairbanks, May 2004
Ecology and conservation of large mammals
physiological ecology of endotherms
resource selection modeling
wildlife population ecology
Gaynor, K.M., P. Branco, J.S. Brashares, D. D’Emille, P. Granli, R.A. Long, and J. Poole. 2018. Effects of human settlement and roads on diel activity patterns of elephants (Loxodonta africana). African Journal of Ecology: In press.
Spitz, D., D. Clark, M.J. Wisdom, M. Rowland, B. Johnson, R.A. Long, and T. Levi. 2018. Fire history influences large-herbivore behavior at circadian, seasonal, and successional scales. Ecological Applications: In press.
Monteith, K.L., R.A. Long, T.R. Stephenson, V.C. Bleich, R.T. Bowyer, and T.N. LaSharr. 2018. Horn size and nutrition in mountain sheep: can ewe handle the truth? Journal of Wildlife Management 82:67-84.
Long, R.A., A. Wambua, J.R. Goheen, T.M. Palmer, and R.M. Pringle. 2017. Climatic variation modulates the indirect effects of large herbivores on small-mammal habitat use. Journal of Animal Ecology 86:739-748.
Tarnita, C.E., J.A. Bonachela, E. Sheffer, J.A. Guyton, T.C. Coverdale, R.A. Long, and R.M. Pringle. 2017. A theoretical foundation for multi-scale regular vegetation patterns. Nature 541:398-401 (Cover article).
Long, R.A., R.T. Bowyer, W.P. Porter, P. Mathewson, K.L. Monteith, S.L. Findholt, B.L. Dick, and J.G. Kie. 2016. Linking habitat selection to fitness-related traits in herbivores: the role of the energy landscape. Oecologia 181:709-720.
Seidler, R.G., R.A. Long, J. Berger, S. Bergen, and J.P. Beckmann. 2015. Identifying impediments to long-distance migration to facilitate conservation. Conservation Biology 29:99-109.
Long, R.A., R.T. Bowyer, W.P. Porter, P. Mathewson, K.L. Monteith, and J.G. Kie. 2014. Behavior and nutritional condition buffer a large-bodied endotherm against direct and indirect effects of climate. Ecological Monographs 84:513-532.
Monteith, K.L., R.A. Long, V.C. Bleich, J.R. Heffelfinger, P.R. Krausman, and R.T. Bowyer. 2013. The effects of harvest, culture, and climate on trends in size of horn-like structures in trophy ungulates. Wildlife Monographs 183.
Lendrum, P.E., C.R. Anderson, Jr., R.A. Long, J.G. Kie, and R.T. Bowyer. 2012. Habitat selection by mule deer during migration: effects of landscape structure and natural-gas development. Ecosphere 3:art82.
Anderson, E.D., R.A. Long, M.P. Atwood, J.G. Kie, T.R. Thomas, P. Zager, and R.T. Bowyer. 2012. Winter resource selection by female mule deer Odocoileus hemionus: functional response to spatiotemporal changes in habitat. Wildlife Biology 18:153-163.
Aho, K.A., R.A. Long, J.G. Kie, and R.T. Bowyer. 2010. A new index for measuring perpendicularity of animal movements in relation to patch boundaries. Ecological Modelling 221:2003-2007.
Long, R.A., J.G. Kie, R.T. Bowyer, and M.A. Hurley. 2009. Resource selection and movements by female mule deer: effects of reproductive stage. Wildlife Biology 15:288-298.
Long, R.A., J.L. Rachlow, and J.G. Kie. 2009. Sex-specific responses of North American elk to habitat manipulation. Journal of Mammalogy 90:423-432.
Long, R.A., J.D. Muir, J.L. Rachlow, and J.G. Kie. 2009. A comparison of two modeling approaches for evaluating wildlife-habitat relationships. Journal of Wildlife Management 73:294-302.
- Alumni Award for Excellence (UI, 2017)
- The Wildlife Society Publication Award for Outstanding Monograph (UI, 2016)
- Alumni Award for Excellence (UI, 2015)
- Outstanding Graduate Researcher in Biology (ISU, 2013)
- American Society of Mammalogists Fellowship (2012)
- U.S. Environmental Protection Agency Science to Achieve Results (STAR) Fellowship (2010-2013)
Allometry of Behavior in Spatially Patterned Resource Landscapes
Behavioral plasticity is constrained by morphology and physiology; because these often scale allometrically with body size, so should behavior. Indeed, the allometry of behavior is predicted to emerge from the interaction of (a) size-varying traits that influence animal performance (e.g., energy requirements), and (b) biotic and abiotic habitat attributes, such as the distribution of resources and microclimates. This project integrates observational, experimental, molecular, and modeling approaches to shed new light on the mechanisms that underpin animal behavior and population dynamics in an African savanna ecosystem that is both spatially and seasonally heterogeneous. The study system (Gorongosa National Park, Mozambique) is characterized by spatially patterned termite mounds that govern the distribution of vegetation, nutrients, and microclimates at broad spatial scales, and that are heavily used by three congeneric antelope species (bushbuck, nyala, and kudu, all Tragelaphus spp.) that vary five-fold in body size. This combination of factors presents an ideal opportunity to study the effects of body size and resource distribution on behavior and population dynamics. The unifying concepts of allometric scaling and resource heterogeneity mean that our insights will be generalizable and applicable across ecosystems, including to the management of North American wildlife populations. Broader impacts include development of an immersive, interdisciplinary field course offered to both U.S. and Mozambican students, broad public dissemination of research results via scientifically rigorous short films, and collaboration with park officials to develop effective wildlife-management policies.
Study Location: Gorongosa National Park, Mozambique.
Timeline: This project was initiated in the fall of 2017 in collaboration with Dr. Rob Pringle and Dr. Corina Tarnita at Princeton University. Two PhD students are currently working on the project: Hallie Walker in the Long Lab and Justine Atkins in the Tarnita lab.
Linking Nutrition to Lamb Survival, Movement, and Disease Transmission in Bighorn Sheep
Disease (primarily pneumonia) has been linked to the episodic decline of bighorn sheep populations throughout their range, including in Idaho. Yet, a complete understanding of the factors that influence susceptibility of bighorn sheep to disease, or of the factors that influence the spread of disease within and among populations, remains elusive. Nutritional condition integrates a variety of complex responses of ungulates to their environment, and individuals in poor condition often have both a higher probability of contracting disease and a lower probability of survival once infected. Moreover, nutritional condition can strongly influence animal movements, which has important implications for the spread of disease. Some evidence suggests that because of their unique physiology and life history, bighorn sheep may be more sensitive to variation in the quality, abundance, or distribution of forage resources than other species of ungulates. The degree to which spatiotemporal variation in the nutritional landscape might modulate disease dynamics in bighorn sheep, however, has not been evaluated. This project is designed to address two broad categories of questions:
Lamb survival: Is early lamb survival modulated by nutrition in two bighorn sheep herds that occupy different nutritional landscapes in Idaho?
- Is late-winter body condition of ewes related to subsequent neonatal mortality from a variety of sources?
- How does late-winter body condition influence use of the nutritional landscape by ewes, and how do those behavioral decisions affect lamb survival?
- How does variation in the nutritional landscape across space and time influence movements of ewes, and what are the ramifications of those movements for lamb survival?
Landscape-scale movements: Is the movement of bighorn sheep within and among populations (and associated potential for spread of disease) influenced by the nutritional landscape in concert with individual traits such as age, sex, and nutritional condition?
- To what degree are movements within sheep populations related to population density, demography, nutritional condition, disease status, and the nutritional landscape?
- Is the propensity of sheep to foray (frequency, duration, distance, return, or disperse) related to factors such as their body condition, the quality of the nutritional landscape within versus outside of their home range, their disease status, or the proximity and density of groups of sheep outside of their home range?
Study Location: Idaho, USA.
Timeline: This project was initiated in the fall of 2017 and is being conducted by Nikie Bilodeau for her MS degree (lamb survival) and Aniruddha Belsare as part of his CMCI post-doc (landscape-scale movement modeling).
Thermal Ecology of Grizzly Bears
The grizzly bear is an iconic species in western North America. Yet, for a variety of reasons, management of grizzly bears is often fraught with controversy. There are currently two populations of grizzly bears in the contiguous United States, both of which are being considered for delisting from the Endangered Species Act. As part of this process, the U.S. Fish and Wildlife service has evaluated the relative contribution of food resources (i.e., quality, availability and distribution of key food resources) to the stability of these populations. In contrast, the potential for climate change to directly influence the distribution and performance of grizzly populations by increasing costs of thermoregulation and activity has received little attention. Large-bodied animals such as grizzly bears have smaller surface-area-to-volume ratios and thicker boundary layers than their smaller-bodied counterparts, and are thus subject to greater constraints on heat dissipation than smaller animals. This biophysical first principle suggests that as temperatures continue to rise, grizzly bears may be forced to invest more resources (i.e., energy and water) into regulating their body temperature, especially near the southern extent of their range. Nevertheless, the relative contribution of thermoregulatory costs to the overall energy budget of grizzly bears is poorly understood, and thus the potential for rising temperatures to limit population distributions has not been evaluated. Furthermore, understanding the relative influence of physical activity and environmental factors on heat balance in grizzly bears could provide important insights into the degree to which bears will be forced to alter their behavior as the climate continues to warm, as well as into what changes in behavior are most likely to occur. The objectives of this project are:
- To understand the relative contribution of thermoregulatory costs to the overall energy budget of a grizzly bear as a function of activity levels and environmental conditions.
- To understand the relative contribution of thermoregulatory costs to the spatiotemporal distribution of grizzly bears, and to predict how that contribution is likely to change as the climate continues to warm.
Study Location: Washington State University, Washington, USA.
Timeline: This project was initiated in the fall of 2017 in collaboration with Dr. Charlie Robbins and Tony Carnahan at Washington State University. We are working with the captive grizzly bears at WSU, and Savannah Rogers is conducting this project for her MS degree.
Predicting Vital Rates of Elk
Pregnancy rates, which in ungulates are directly affected by nutritional condition in late summer, can strongly influence the finite rate of increase of a population (λ). As a result, information on pregnancy rates can be used by managers to predict population trends and make decisions ranging from allowable harvest to access restrictions. Reliably quantifying variation in nutritional condition and/or associated vital rates, however, has previously required the capture and handling of numerous individuals from each population of interest, making those data expensive, time-consuming, and risky to collect. Modern vegetation indices such as NDVI and EVI provide a mechanism for mapping the nutritional landscape available to ungulates, but thus far few researchers have attempted to link those indices with on-the-ground measures of forage quality and abundance, as well as behavior, condition, and vital rates of large herbivores. The primary objectives of this project are to: 1) model the relationship between remotely sensed vegetation indices and empirical estimates of spatiotemporal variation in forage quality and abundance for elk; and 2) combine the resulting forage model with data on elk habitat selection and pregnancy rates to model spatiotemporal variation in pregnancy rates as a function of habitat quality at a Statewide scale.
Study Location: Idaho, USA.
Timeline: This project was initiated in the fall of 2015 and is being conducted by Sierra Robatcek for her MS degree.
The Elephants of Gorongosa: An Integrated Approach to Conservation and Conflict Mitigation in the Shadow of War
Elephants are the world’s largest extant land mammal, and are an iconic species throughout sub-Saharan Africa. Nevertheless, elephants regularly come into conflict with humans, and management of elephant populations is often fraught with controversy. Gorongosa National Park, in central Mozambique, was once home to more than 2,000 elephants. Most (>90%) of those elephants were killed to feed soldiers during the Mozambican Civil War (1977-1992) and to fund the purchase of arms and ammunition through the sale of ivory. Subsequent recovery of the Park’s elephant population under the auspices of the Gorongosa Restoration Project (GRP) has been an unparalleled conservation success story. However, as this population has recovered, increased crop-raiding by elephants along park boundaries (now heavily cultivated) has threatened to undo restoration efforts, with conflicts between elephants and farmers posing a serious threat to the overall success of the GRP. Human-elephant conflict at Gorongosa is a complex issue that requires urgent attention to avoid further diminishing the tolerance of farmers and simultaneously jeopardizing elephants’ survival. Implementing effective non-lethal strategies for preventing crop damage by these elephants is a complicated task, and the objectives of this project are to:
- Collect detailed data on elephant crop damage;
- Quantify temporal and spatial patterns of crop raiding by intensive monitoring of individuals with satellite collars;
- Evaluate the effectiveness of different strategies for deterring elephants from crop raiding, including bee hives, chili fences, and combinations of the two.
Study Location: Gorongosa National Park, Mozambique.
Timeline: This project was completed in the spring of 2018 by Paola Branco for her MS degree.
Workshops OrganizedSpatial Distribution, Movement, and Home Range Analysis
I have taught half of this week-long workshop (co-taught with Dr. John Kie) twice at the USFWS National Conservation Training Center (2011 and 2012) and five times at the Idaho State University GIS Center (2012-2015).
Analysis of Resource Selection by Animals
I presented this 2-day workshop on resource selection analysis (background, theory, and application) to the Wyoming Cooperative Fish and Wildlife Research Unit at the University of Wyoming in 2013 and 2018, to the Department of Natural Resources and Environmental Science at the University of Nevada Reno in 2014, to the Oregon Chapter of the Wildlife Society in 2018, and to the Caesar Kleberg Wildlife Research Institute at Texas A&M University in 2018.