Source: UNIVERSITY OF WYOMING submitted to
EVALUATING THE INFLUENCE OF CLIMATE CHANGE ON THE COMMINGLING OF LIVESTOCK AND WILD UNGULATES: QUANTIFYING THE RISKS ACROSS WYOMING RANGELAN
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1004588
Grant No.
2015-67012-22896
Project No.
WYO-00623-15
Proposal No.
2014-01928
Multistate No.
(N/A)
Program Code
A7201
Project Start Date
Dec 1, 2014
Project End Date
Nov 30, 2016
Grant Year
2015
Project Director
Merkle, J. A.
Recipient Organization
UNIVERSITY OF WYOMING
1000 E UNIVERSITY AVE DEPARTMENT 3434
LARAMIE,WY 82071-2000
Performing Department
(N/A)
Non Technical Summary
The rangelands of the Mountain West support both livestock and wild ungulate species, and the degree of commingling between them is a growing challenge for livestock and wildlife managers. Disease transmission and livestock depredation by shared predators are two risks that are strongly influenced by commingling, with potentially high economic costs for the livestock industry. Climate change is altering plant phenology, which strongly influences the seasonal distribution of wild ungulates. Yet, it remains unclear how such landscape-level changes in the forage that wild ungulates track will influence interactions with livestock. To proactively manage rangelands in the face of climate change, a mechanistic understanding of where commingling hotspots exist and how they will be altered is required. The goal of the proposed work is to develop a framework for understanding the ecology of wildlife-livestock commingling, with particular focus on how climate change will influence the distribution of wild ungulates and livestock on shared range. I will carry out this project using existing GPS collar data on elk (Cervus elaphus) and bighorn sheep (Ovis canadensis) in six study areas across Wyoming rangelands. Three study areas in the Greater Yellowstone Ecosystem occur in systems where elk commingle with cattle, influencing livestock depredation and transmission of Brucella abortis from elk to livestock (n = 359 collared individuals). The other three study areas represent examples where bighorn sheep have the potential to interact with domestic sheep and become infected by Pasteurella spp. - a pathogen that causes pneumonia outbreaks in bighorn sheep (n = 77 collared individuals). My objectives are threefold. First, I will examine how changes in plant phenology influence elk and bighorn sheep seasonal habitat use by testing and refining the Green Wave Hypothesis - a novel framework for understanding the link between animal movement and plant phenology. Second, I will quantify the distribution of cattle and sheep by developing a spatially-explicit temporal landscape of livestock within each study area. Finally, I will combine results from objectives 1 and 2 and develop predictions of how climate change is likely to influence the present and future distribution of commingling hotspots. Outcomes will provide information to identify the locations where proactive management can alleviate risks posed by climate change. The proposed project will address the important societal challenge of mitigating and adapting to climate change variability by providing the knowledge livestock and wildlife managers need to adapt to new risks. The proposed work simultaneously contributes to the AFRI program area priority of agriculture economics and rural communities, because it will provide tools to reduce ranching costs associated with disease or depredation, thereby enhancing the viability of ranching operations. I expect the results of this study to stimulate the growth of a new applied field focused on the ecology and management of wildlife-livestock commingling.
Animal Health Component
0%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1210790107060%
1350830106040%
Knowledge Area
135 - Aquatic and Terrestrial Wildlife; 121 - Management of Range Resources;

Subject Of Investigation
0790 - Rangelands, other; 0830 - Wild animals;

Field Of Science
1070 - Ecology; 1060 - Biology (whole systems);
Goals / Objectives
The major goal is to develop a framework for understanding the ecology of wildlife-livestock commingling, particularly with regard to landscape-level changes in plant phenology that climate change will bring. The project has the following three goals.Objective 1. Examine how changes in plant phenology influence elk and bighorn sheep seasonal habitat use in areas that overlap with livestock. Specifically, I will develop habitat selection models to test and refine the link between plant phenology and animal movement.Objective 2. Characterize the spatio-temporal distribution of cattle and sheep by determining how range managers move livestock across seasonal grazing allotments. Specifically, I will compile past grazing records on public and private lands and develop a spatially-explicit temporal landscape prediction of livestock distribution.Objective 3. Develop predictions of how climate change is likely to influence the present and future distribution of commingling hotspots. In this final step, I will use projections of phenological alterations caused by climate change to predict the distribution of both livestock and wild ungulates, and where they commingle. Commingling hotspots will be evaluated from the perspective of B. abortus transmission from elk to cattle, Pasteurella spp. transmission from domestic to bighorn sheep, and elk-cattle commingling in areas occupied by wolves and grizzly bears.
Project Methods
Objective 1. Phenology tracking in elk and bighorn sheep. To determine how changes in plant phenology influence large ungulate habitat use, I will develop seasonal Step Selection Function (SSF) movement models, which are based on a comparison of connected GPS locations (i.e., observed steps) with un-used steps where an animal could have gone. With this model in place, I can evaluate an animal's GPS movement path to determine if individuals choose habitats in early phenological stages, as predicted by the green wave hypothesis (GWH), and identify the role of memory during movement. To characterize phenological variation on the landscape, I will use the normalized difference vegetation index (NDVI), which is a remotely-sensed metric of "greenness" widely used as a measure of plant phenology. To empirically investigate how memory may simultaneously influence phenology tracking by ungulates, I will characterize each step with additional variables that characterize the past experience of the individual animal. I will build two sets of models; those testing phenology tracking as predicted by the GWH, and those that include memory variables. Models will be parameterized using likelihood methods under a mixed effects conditional logistic regression framework. Objective 2. Spatio-temporal distribution of livestock. For each study area, I will identify and geo-code each cattle or sheep pasture that overlaps with observed GPS locations of collared wild ungulates, and develop a database of stocking rate, and turnout and pull-off dates. For public lands (which constitute the majority of the study areas), I will compile publically available information from the U.S. Forest Service, U.S. Bureau of Land Management, and U.S. Natural Resources Conservation Service. For the remaining private lands, I will compile this information through site visits or by phone, depending on feasibility. Once the information is compiled, I will use kernel methods to develop livestock density estimates in each pasture on a daily basis throughout the year. Then, using a space-time modeling approach, where each pixel (i.e., pasture) on the landscape has a livestock density estimate, I will develop a time-based distribution of livestock throughout the study period. The product will provide daily maps of the distribution of livestock within each study area to be compared with current and future wild ungulate distribution. Objective 3. Identifying commingling hotspots under climate change. To determine how climate change will influence the present and future distribution of commingling hotspots, I will estimate wild ungulate distribution based on predicted changes to the onset and speed of vegetation growth. I will develop scenarios for 0 to 100 years (by increments of 10) into the future. Using the mean NDVI as a baseline, I will simulate 90 different landscapes by altering NDVI profiles at each pixel. First, I will alter NDVI profiles to take into account variation in predicted change in delayed first green-up. Second, I will alter NDVI profiles to take into account the extremes in rate of green-up that could realistically be observed in the future. These simulated landscapes provide reasonable changes in plant phenology due to climate change. Predicting distribution of wild ungulates. Using the simulated landscapes, along with parameter estimates from Objective 1, I will develop population-level utilization distributions for each species and each study area that can be compared with livestock distribution. SSF movement models will be translated into a population-based time-series simulation following Potts et al. (2014). With this method, the probability distribution of animals across the landscape can be calculated for each time interval, and the summation of these distributions reveals the population-level distribution. For each of the simulated landscapes, I will calculate a seasonal and annual steady state distribution for elk and bighorn sheep. If the results of Objective 1 indicate that memory influences phenology tracking, I will specify a burn-in period of 1 year to develop spatial memory for the simulated individuals. Identifying future commingling hotspots. To identify the present and future distribution of commingling hotspots, I will compare seasonal forecasts of wild ungulate distribution with the time-based distribution of livestock (Objective 2). I will first identify the date of arrival and departure from summer and winter ranges for elk and bighorn sheep based on climate change simulations. The results will shed light on how climate change will affect the timing of migration and residence time on seasonal ranges, ultimately affecting when livestock managers can turnout livestock onto seasonal pastures. Second, I will compare seasonal wild ungulate distributions with the time-based distribution of livestock using well-developed utilization distribution comparison techniques. To identify commingling hotspots in each study area, I will subtract seasonal probability distributions of wild ungulates from livestock distribution, providing an index of commingling risk. Finally, to identify areas where climate-induced commingling risk will change, I will develop maps where the index of risk for each of the 90 simulated landscapes is subtracted by the simulated distribution without climate change effects. This analysis will indicate which pastures will be subject to the most change over time. Temporal trends in the spatial distribution of commingling hotspots due to climate change will provide livestock and wildlife managers information to forecast and proactively manage (e.g., modify turnout dates) the risks involved with B. abortus transmission from elk to cattle, Pasteurella spp. transmission from domestic to bighorn sheep, and depredation by wolves and grizzly bears. Efforts. I will: 1) update my personal research, ResearchGate , and LinkedIn websites with information, goals, objectives, and results of the research program; 2) by Aug 2015, present initial research findings from Objective 1 at WY Chapter of The Wildlife Society (TWS) annual conference; 3) by Nov 2015, submit publication(s) pertaining to Objective 1; 4) by Aug 2016, present results from Objective 3 at WY Chapter of TWS annual conference, and present published results at the Ecological Society of America annual conference; 5) by Oct 2016, present applied aspects of published results at TWS annual conference; 6) by Nov 2016, submission of final publications from Objective 3. Evaluation. Each activity specified in the timeline will be used as a milestone to evaluate progress towards my objectives. In addition, I will develop a written update (every four months) explaining how my training has influenced my career development and mentoring objectives. This document will be shared with Dr. Kauffman (mentor), so progress can be evaluated. The main indicators of success will be presentations and submission of research findings to peer-review journals. Indicators will also include successful mentoring of undergraduate and graduate students, development of collaborations among involved stakeholders, completion of teaching proposed seminar, and publication acceptance in broad-reaching, high-quality journals. My dissemination plan is directly related to my timeline of activities, where each year I will present findings at state, and international research conferences, provide outreach to livestock and wildlife managers, and publish findings in peer-review journals.

Progress 12/01/14 to 11/30/16

Outputs
Target Audience:My efforts have reached the following audiences: 1) research ecologists and biologists; 2) wildlife biologists; 3) wildlife and livestock managers; 4) habitat ecologists and managers; and 5) land managers. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?-I have been able to interact and work with a number of stake holders in Wyoming, including wildlife biologists from Wyoming Game and Fish Department, a livestock manager with USDA APHIS, land managers from BLM and the State of Wyoming, and a few private land owners within the elk study areas. - I have been able to interact with Dr. Matt Kauffman (Professor, University of Wyoming) and Dr. Kevin Monteith (Assistant Professor, University of Wyoming) in one-on-one discussion/training meetings, in a group comprised of the three of us, and in a group with their graduate students discussing a graduate student's project. - With Dr. Matt Kauffman as a co-PI, we have raised over $100,000 in funding to continue the work that I am doing and seek out a few other avenues for understanding the ecology andconservation of migratory ungulates. - I was the sole/lead instructor for 2 graduate level courses: Zoo 5890-04 (3 credits, spring 2016)- Quantitative analysis of animal movement and habitat selection; Zoo 5890-08 (2 credits, fall 2015) - Introduction to R. - I attended and presented my work at the following conferences: 1) Society for Integrative and Comparitive Biology Annual Meeting, Portland, OR, 2016; 2) WY Chapter of The Wildlife Society Annual Conference, Cody, WY, 2016; 13th Biennial Scientific Conference on the Greater Yellowstone, Jackson Lake Lodge, WY, 2016. - I co-organizeda symposium entitled, "Science and management: turning disconnect into synergy" at The Wildlife Society Annual Conference, 2016. How have the results been disseminated to communities of interest?I have presented all or parts of this work at the following professional research conferences or seminars: - "Evaluating fitness outcomes of habitat selection behavior." Merkle, J.A. Alaska Science Center, Anchorage, AK. 2016. - "The importance of temporal habitat dynamics for understanding animal behavior and distribution." Merkle, J.A. University of Idaho, 2015. - "Linking plant phenology and elk migratory behavior to predict brucellosis risk in the Yellowstone ecosystem." Merkle, J.A., Cross, P.C., Scurlock, B.M., and Kauffman, M.J. Presentation in Symposium entitled "Are migratory animals superspreaders of disease?" Society for Integrative and Comparative Biology Annual Meeting, Portland, OR, 2016. - "The role of memory in shaping migratory behavior." Merkle, J.A., Sawyer, H., and Kauffman, M.J. The WY Chapter of The Wildlife Society Annual Conference, Cody, WY, 2016. - "Linking spring phenology with mechanistic models of elk movement to predict brucellosis transmission risk." Merkle, J.A., Cross, P.C., Scurlock, B.M., and Kauffman, M.J. 13th Biennial Scientific Conference on the Greater Yellowstone, Jackson Lake Lodge, WY, 2016. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? All of these goals and objectives have been accomplished and have are either published or in preparation for submission in the following journal articles: Merkle, J.A., P.C. Cross, B.M. Scurlock, and M.J. Kauffman. Linking plant phenology and elk migratory behavior to predict brucellosis risk in the Yellowstone ecosystem. Rejected from Journal of Animal Ecology after being sent out to review. In the process of being resubmitted toEcological Applications. Merkle, J.A., K.L. Monteith, E.O. Aikens, M.M. Hayes, K.R. Hershey, A.D. Middleton, B.A. Oates, H. Sawyer, B.M. Scurlock, M.J. Kauffman. 2016. Large herbivores surf waves of green-up in spring. Proceedings of the Royal Society B 283:20160456.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Merkle, J.A., K.L. Monteith, E.O. Aikens, M.M. Hayes, K.R. Hershey, A.D. Middleton, B.A. Oates, H. Sawyer, B.M. Scurlock, M.J. Kauffman. 2016. Large herbivores surf waves of green-up in spring. Proceedings of the Royal Society B 283:20160456.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Merkle, J.A., J.R. Potts, and D. Fortin. 2017. Energy benefits and emergent space use patterns of an empirically parameterized model of memory-based patch selection. Oikos 126(2): 185196.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Sigaud, M., J.A. Merkle, S.G. Cherry, and D. Fortin. 2017. Collective decision-making promotes fitness loss in a fusion-fission society. Ecology Letters 20(1): 3340.
  • Type: Journal Articles Status: Under Review Year Published: 2017 Citation: Aikens, E.O., M.J. Kauffman, J.A. Merkle, S.P. Dwinnell, G.L. Fralick, and K.L. Monteith. The greenscape shapes surfing of spring resource waves in a large migratory herbivore. Under review with Ecology Letters.
  • Type: Journal Articles Status: Under Review Year Published: 2017 Citation: Merkle, J.A., J.L. Polfus, J.J. Derbridge, and K.S. Heinmeyer. Dietary niche partitioning among black bears, grizzly bears and wolves in a multi-prey ecosystem. Under review with Canadian Journal of Zoology.
  • Type: Journal Articles Status: Under Review Year Published: 2017 Citation: Barocas, A., R. Hefner, M. Ucko, J.A. Merkle, and E. Geffen. Arabian wolves spatially favor but temporally avoid human activity in an extremely arid landscape. Under review with Journal of Animal Ecology.
  • Type: Journal Articles Status: Under Review Year Published: 2017 Citation: Middleton, A.D., J.A. Merkle, D.E. McWhirter, J.G. Cook, R.C. Cook, M.D. Jimenez, P.J. White, and M.J. Kauffman. Green-wave surfing affects fitness in a large migratory herbivore. Under review with Proceedings of the National Academy of Science.
  • Type: Journal Articles Status: Other Year Published: 2017 Citation: Merkle, J.A., P.C. Cross, B.M. Scurlock, and M.J. Kauffman. Linking plant phenology and elk migratory behavior to predict brucellosis risk in the Yellowstone ecosystem. Rejected from Journal of Animal Ecology after being sent out to review. Preparing to resubmit to Ecological Applications.
  • Type: Journal Articles Status: Other Year Published: 2017 Citation: Morrison T.A., J.A. Merkle, E.O. Aikens, J.L. Beck, R.B. Boone, S.P. Dwinnell, B. Griffith, G.C. Hopcraft, A.D. Middleton, K.L. Montieth, B.A. Oates, H. Sawyer, K.T. Smith, J.A. Stabach, K.L. Taylor, and M.J. Kauffman. Fidelity constrains movements of migratory ungulates. Rejected from Ecology Letters after review. Preparing to resubmit to Oikos.


Progress 12/01/14 to 11/30/15

Outputs
Target Audience:My efforts have reached the following audiences:1) research ecologists and biologists; 2)wildlife biologists; 3)wildlife and livestockmanagers; 4) habitat ecologists andmanagers;and 5) land managers. Changes/Problems:I have only two changes to report. 1) Afterdiscussions with domestic sheep managers and bighorn sheep managers, it has become clear that the state of Wyoming wild-domestic sheep conflict management plans are set in stone for the foreseeable future. Therefore, any new research that comes to light will likely not be considered for years to come. This information only affects our objectives in that I will not carry out objectives 2 and3 with respect to bighorn sheep. I will only focus on predicting comingling risk between elk and cattle with respect to brucellosis transmission risk. Nonetheless, I am still carrying out objective 1 with respect to bighorn sheep because there is still a lack of information on understanding the link between plant phenology and behavior in bighorn sheep. 2) In discussions with livestock managers, it seems that our livestock distribution data on private lands will not be as robust as originally proposed. For example, in a previous project, local managers attempted to develop a database of livestock distribution on privatelandsthrough discussions with landowners, and this endeavor proved to be rather difficult and led to an incomplete database which was unusable. We have decided on using private land parcel data that has been classified for grazing livestock. Such data are similar to the proposed butlackthe temporal component. In other words, within a parcel, we will be unable to quantify where and whenlandowners graze their livestock, only that the parcel likely has livestock somewhere on it. What opportunities for training and professional development has the project provided?-I have been able to interact and work with a number of stake holders in Wyoming, includingwildlife biologists from Wyoming Game and Fish Department, a livestock manager with USDA APHIS, land managers from BLM and the State of Wyoming, and a few private land owners within the elk study areas. - I have been able to interact with Dr. Matt Kauffman (Professor, University of Wyoming) and Dr. Kevin Monteith (Assistant Professor, University of Wyoming) in one-on-one discussion/training meetings, in agroup comprised of the three of us, andin a group with theirgraduate students discussing a graduate student'sproject. -I completed the Wildlife Society's Leadership Institute training course, which consisted of multipleessay/workbook/readingassignments and numerous group discussions on the topic of leadership over the course of 5 months. -I attended the following conferences: 1) United States Department of Agriculture - National Institute of Food and Agriculture Project Directors' Meeting, Washington DC,2015; 2)Annual meeting of the Ecological Society of America,Baltimore, MD, 2015; 3)22nd Annual conference of The Wildlife Society, Winnipeg, Manitoba, 2015, 4)Brucellosis Research Group Meeting, Jackson, WY, 2015; 5) The Wyoming Chapter of The Wildlife Society annual meeting, Lander, WY, 2015; 6)Sustaining Big Game Migrations in the West:Science, Policy, and People,An Emerging Issues Forum, Laramie, WY, 2015. How have the results been disseminated to communities of interest?I have presented researchfindings from this study at the following professional research conferences: "Can ungulates actually select areas at peak rate of green-up?" Merkle, J.A., Kauffman, M.J., Monteith, K.L., Aikens, E.O., Hayes, M.M., Hersey, K.R., Sawyer, H., and Scurlock, B.M. The Wyoming Chapter of The Wildlife Society and Wyoming Landscape Conservation Initiative annual conference, Lander, Wyoming, 2015. "Do large herbivores surf NDVI-based rate of green-up?" Merkle, J.A., Kauffman, M.J., Monteith, K.L., Aikens, E.O., Hayes, M.M., Hersey, K.R., Sawyer, H., and Scurlock, B.M. 22nd Annual conference of The Wildlife Society, Winnipeg, Manitoba, 2015. "Linking plant phenology and elk migratory behavior to predict brucellosis risk in the Yellowstone ecosystem." Merkle, J.A. United States Department of Agriculture - National Institute of Food and Agriculture Project Directors' Meeting, Washington DC, 2015. I have also presented researchfindings from this study at the following management orientedconferences: "Predicting brucellosis transmission risk using phenology-based movement models of elk." Merkle, J.A. WyomingAnnual Cooperator's Meeting, with presence from Wyoming Game and Fish Department, U.S. Fish and Wildlife Service, and U.S. Geological Survey. Cheyenne, WY, 2015. "Linking plant phenology and elkmigratory behavior to predictbrucellosis risk in Wyoming." Merkle, J.A., Cross, P.C., Scurlock, B.M., and Kauffman, M.J.Brucellosis Research Group Meeting, Jackson, WY, 2015. What do you plan to do during the next reporting period to accomplish the goals?My plans during the next reporting period are to: 1)Submit a manuscript that tests one of the main assumptions about how migratory elk and bighorn sheep track and select temporally changing resources over time. This analysis was an important first step in developing the elk movement models. The analyses are complete, and the manuscript is written.I just need to make some final changes and get co-author approval prior to submission. 2) Develop and analyze movement models that incorporate memory and past experience into how elk and bighorn sheep track and select temporally changing resources during their migration. This analysis will be written up into a scientific publication. 3) Use the results from above to continue refiningelk movement models andsimulations of elk distribution during the brucellosis transmissionrisk season. 4) Develop maps of elk distribution during the brucellosis transmission risk season for a variety of years with varying observed and simulatedweather patterns, and make them available to wildlife and livestock managers through a web-based mapping platform that includes private lands and the livestockgrazing allotment information on public lands. 5) Write up the movement modeling and elk distribution simulationresults into a manuscript for publication. 6) Present results at local and regional professional conferences as well as the local Brucellosis Research Group Meeting, which includes all of the local managementpartners who will benefit from the project's results. 7) Teach a graduate level course on quantitative methods in animal movement and habitat selection modeling.

Impacts
What was accomplished under these goals? For objective 1, I havecompiled the elk and bighorn sheep GPS collardatabases,anddeveloped, and parameterized, elk movement models. For objective 2, I have compiled livestock grazing allotment information on public lands, as well as a database of private lands that are classifiedfor livestock use in the elk study areas. For objective 3, I have completedinitial simulations of elk distribution during the brucellosis transmissionrisk season using snow and vegetation data from heavy and light snow years.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Fortin, D., J.A. Merkle, M. Sigaud, S.G. Cherry, S. Plante, A. Drolet, M. Labrecque. 2015. Temporal dynamics in the foraging decisions of large herbivores. Animal Production Science 55(3): 376383.
  • Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Cherry, S.G., J.A. Merkle, D. Fortin, M. Sigaud, and G.A. Wilson. Genetic and population viability for plains bison (Bison bison bison) residing at the interface between protected and private lands. Under review with Canadian Journal of Zoology.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Losier, C., S. Couturier, M-H. St-Laurent, P. Drapeau, C. Dussault, T. Rudolph, V. Brodeur, J.A. Merkle, and D. Fortin. 2015. Adjustments in habitat selection to changing availability induce fitness costs for a threatened ungulate. Journal of Applied Ecology 52(2): 496504.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Merkle, J.A., S.G. Cherry, and D. Fortin. 2015. Bison distribution under conflicting foraging strategies: site fidelity versus energy maximization. Ecology 96:17931801.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Derbridge, J.J., J.A. Merkle, M.E. Bucci, P. Callahan, J.L. Koprowski, J.L. Polfus, and P.R. Krausman. 2015. Experimentally derived ?13C and ?15N discrimination factors for gray wolves and the impact of prior information in Bayesian mixing models. PloS ONE 10(3): e0119940.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Merkle, J.A., M. Sigaud, and D. Fortin. 2015. To follow or not? How animals in fusion-fission societies handle conflicting information during group decision-making. Ecology Letters 18(8): 799806.
  • Type: Other Status: Published Year Published: 2015 Citation: Merkle, J.A. 2015. Invited Book Review of Ecology of Climate Change: the Importance of Biotic Interactions. Journal of Wildlife Management 79(7): 1208:1209.
  • Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Merkle, J.A., J.R. Potts, and D. Fortin. Energy benefits and emergent space use patterns of memory-based patch selection. Under review with Oikos.
  • Type: Journal Articles Status: Submitted Year Published: 2015 Citation: Siguad, M., J.A. Merkle, S.G. Cherry, and D. Fortin. Collective decision-making promotes fitness loss in a fusion-fission society. Submitted to Nature.