1
|
Sells SN, Podruzny KM, Nowak JJ, Smucker TD, Parks TW, Boyd DK, Nelson AA, Lance NJ, Inman RM, Gude JA, Bassing SB, Loonam KE, Mitchell MS. Integrating basic and applied research to estimate carnivore abundance. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2714. [PMID: 36184581 DOI: 10.1002/eap.2714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 06/07/2022] [Accepted: 06/16/2022] [Indexed: 06/16/2023]
Abstract
A clear connection between basic research and applied management is often missing or difficult to discern. We present a case study of integration of basic research with applied management for estimating abundance of gray wolves (Canis lupus) in Montana, USA. Estimating wolf abundance is a key component of wolf management but is costly and time intensive as wolf populations continue to grow. We developed a multimodel approach using an occupancy model, mechanistic territory model, and empirical group size model to improve abundance estimates while reducing monitoring effort. Whereas field-based wolf counts generally rely on costly, difficult-to-collect monitoring data, especially for larger areas or population sizes, our approach efficiently uses readily available wolf observation data and introduces models focused on biological mechanisms underlying territorial and social behavior. In a three-part process, the occupancy model first estimates the extent of wolf distribution in Montana, based on environmental covariates and wolf observations. The spatially explicit mechanistic territory model predicts territory sizes using simple behavioral rules and data on prey resources, terrain ruggedness, and human density. Together, these models predict the number of packs. An empirical pack size model based on 14 years of data demonstrates that pack sizes are positively related to local densities of packs, and negatively related to terrain ruggedness, local mortalities, and intensity of harvest management. Total abundance estimates for given areas are derived by combining estimated numbers of packs and pack sizes. We estimated the Montana wolf population to be smallest in the first year of our study, with 91 packs and 654 wolves in 2007, followed by a population peak in 2011 with 1252 wolves. The population declined ~6% thereafter, coincident with implementation of legal harvest in Montana. Recent numbers have largely stabilized at an average of 191 packs and 1141 wolves from 2016 to 2020. This new approach accounts for biologically based, spatially explicit predictions of behavior to provide more accurate estimates of carnivore abundance at finer spatial scales. By integrating basic and applied research, our approach can therefore better inform decision-making and meet management needs.
Collapse
Affiliation(s)
- Sarah N Sells
- Wildlife Biology Program, University of Montana, Missoula, Montana, USA
| | | | | | - Ty D Smucker
- Montana Fish, Wildlife and Parks, Great Falls, Montana, USA
| | - Tyler W Parks
- Montana Fish, Wildlife and Parks, Missoula, Montana, USA
| | - Diane K Boyd
- Montana Fish, Wildlife and Parks, Kalispell, Montana, USA
| | | | | | | | - Justin A Gude
- Montana Fish, Wildlife and Parks, Helena, Montana, USA
| | - Sarah B Bassing
- School of Environmental and Forest Sciences, University of Washington, Seattle, Washington, USA
| | - Kenneth E Loonam
- Department of Fish and Wildlife, Oregon State University, Corvallis, Oregon, USA
| | | |
Collapse
|
2
|
Sells SN, Mitchell MS, Podruzny KM, Ausband DE, Emlen DJ, Gude JA, Smucker TD, Boyd DK, Loonam KE. Competition, prey, and mortalities influence gray wolf group size. J Wildl Manage 2022. [DOI: 10.1002/jwmg.22193] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sarah N. Sells
- Montana Cooperative Wildlife Research Unit, Wildlife Biology Program, 205 Natural Sciences Building University of Montana, Missoula Montana 59812 USA
| | - Michael S. Mitchell
- U.S. Geological Survey, Montana Cooperative Wildlife Research Unit, Wildlife Biology Program, 205 Natural Sciences Building University of Montana Missoula Montana 59812 USA
| | | | - David E. Ausband
- U.S. Geological Survey, Idaho Cooperative Fish and Wildlife Research Unit, 875 Perimeter Drive MS 1141 University of Idaho Moscow Idaho 83844 USA
| | - Douglas J. Emlen
- Division of Biological Sciences University of Montana Missoula Montana 59812
| | - Justin A. Gude
- Montana Fish, Wildlife and Parks 1420 E. 6th St. Helena MT 59620
| | - Ty D. Smucker
- Montana Fish, Wildlife and Parks 4600 Giant Springs Road Great Falls MT 59405
| | - Diane K. Boyd
- Montana Fish, Wildlife and Parks 490 North Meridian Road Kalispell MT 59901
| | - Kenneth E. Loonam
- Montana Cooperative Wildlife Research Unit, Wildlife Biology Program, 205 Natural Sciences Building University of Montana, Missoula Montana 59812 USA
| |
Collapse
|
3
|
Sells SN, Mitchell MS, Ausband DE, Luis AD, Emlen DJ, Podruzny KM, Gude JA. Economical defence of resources structures territorial space use in a cooperative carnivore. Proc Biol Sci 2022; 289:20212512. [PMID: 35016539 PMCID: PMC8753142 DOI: 10.1098/rspb.2021.2512] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 12/08/2021] [Indexed: 01/14/2023] Open
Abstract
Ecologists have long sought to understand space use and mechanisms underlying patterns observed in nature. We developed an optimality landscape and mechanistic territory model to understand mechanisms driving space use and compared model predictions to empirical reality. We demonstrate our approach using grey wolves (Canis lupus). In the model, simulated animals selected territories to economically acquire resources by selecting patches with greatest value, accounting for benefits, costs and trade-offs of defending and using space on the optimality landscape. Our approach successfully predicted and explained first- and second-order space use of wolves, including the population's distribution, territories of individual packs, and influences of prey density, competitor density, human-caused mortality risk and seasonality. It accomplished this using simple behavioural rules and limited data to inform the optimality landscape. Results contribute evidence that economical territory selection is a mechanistic bridge between space use and animal distribution on the landscape. This approach and resulting gains in knowledge enable predicting effects of a wide range of environmental conditions, contributing to both basic ecological understanding of natural systems and conservation. We expect this approach will demonstrate applicability across diverse habitats and species, and that its foundation can help continue to advance understanding of spatial behaviour.
Collapse
Affiliation(s)
- Sarah N. Sells
- Montana Cooperative Wildlife Research Unit, Wildlife Biology Program, University of Montana, Missoula, MT, USA
| | - Michael S. Mitchell
- US Geological Survey, Montana Cooperative Wildlife Research Unit, Wildlife Biology Program, University of Montana, Missoula, MT, USA
| | - David E. Ausband
- US Geological Survey, Idaho Cooperative Fish and Wildlife Research Unit, University of Idaho, Moscow, ID, USA
| | - Angela D. Luis
- Wildlife Biology Program, University of Montana, Missoula, MT, USA
| | - Douglas J. Emlen
- Division of Biological Sciences, University of Montana, Missoula, MT, USA
| | | | | |
Collapse
|
4
|
|
5
|
O'Neil ST, Vucetich JA, Beyer DE, Hoy SR, Bump JK. Territoriality drives preemptive habitat selection in recovering wolves: Implications for carnivore conservation. J Anim Ecol 2020; 89:1433-1447. [PMID: 32145068 DOI: 10.1111/1365-2656.13199] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 02/05/2020] [Indexed: 11/29/2022]
Abstract
According to the ideal-free distribution (IFD), individuals within a population are free to select habitats that maximize their chances of success. Assuming knowledge of habitat quality, the IFD predicts that average fitness will be approximately equal among individuals and between habitats, while density varies, implying that habitat selection will be density dependent. Populations are often assumed to follow an IFD, although this assumption is rarely tested with empirical data, and may be incorrect when territoriality indicates habitat selection tactics that deviate from the IFD (e.g. ideal-despotic distribution or ideal-preemptive distribution). When territoriality influences habitat selection, species' density will not directly reflect components of fitness such as reproductive success or survival. In such cases, assuming an IFD can lead to false conclusions about habitat quality. We tested theoretical models of density-dependent habitat selection on a species known to exhibit territorial behaviour in order to determine whether commonly applied habitat models are appropriate under these circumstances. We combined long-term radiotelemetry and census data from grey wolves Canis lupus in the Upper Peninsula of Michigan, USA to relate spatiotemporal variability in wolf density to underlying classifications of habitat within a hierarchical state-space modelling framework. We then iteratively applied isodar analysis to evaluate which distribution of habitat selection best described this recolonizing wolf population. The wolf population in our study expanded by >1,000% during our study (~50 to >600 individuals), and density-dependent habitat selection was most consistent with the ideal-preemptive distribution, as opposed to the ideal-free or ideal-despotic alternatives. Population density of terrestrial carnivores may not be positively correlated with the fitness value of their habitats, and density-dependent habitat selection patterns may help to explain complex predator-prey dynamics and cascading indirect effects. Source-sink population dynamics appear likely when species exhibit rapid growth and occupy interspersed habitats of contrasting quality. These conditions are likely and have implications for large carnivores in many systems, such as areas in North America and Europe where large predator species are currently recolonizing their former ranges.
Collapse
Affiliation(s)
- Shawn T O'Neil
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr., Houghton, MI, USA
| | - John A Vucetich
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr., Houghton, MI, USA
| | - Dean E Beyer
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr., Houghton, MI, USA.,Wildlife Division, Michigan Department of Natural Resources, 1990 U.S. Hwy 41 So, Marquette, MI, USA
| | - Sarah R Hoy
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr., Houghton, MI, USA
| | - Joseph K Bump
- Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, St. Paul, MN, USA
| |
Collapse
|
6
|
Ditmer MA, Fieberg JR, Moen RA, Windels SK, Stapleton SP, Harris TR. Moose movement rates are altered by wolf presence in two ecosystems. Ecol Evol 2018; 8:9017-9033. [PMID: 30271563 PMCID: PMC6157672 DOI: 10.1002/ece3.4402] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 06/22/2018] [Accepted: 07/02/2018] [Indexed: 11/08/2022] Open
Abstract
Predators directly impact prey populations through lethal encounters, but understanding nonlethal, indirect effects is also critical because foraging animals often face trade-offs between predator avoidance and energy intake. Quantifying these indirect effects can be difficult even when it is possible to monitor individuals that regularly interact. Our goal was to understand how movement and resource selection of a predator (wolves; Canis lupus) influence the movement behavior of a prey species (moose; Alces alces). We tested whether moose avoided areas with high predicted wolf resource use in two study areas with differing prey compositions, whether avoidance patterns varied seasonally, and whether daily activity budgets of moose and wolves aligned temporally. We deployed GPS collars on both species at two sites in northern Minnesota. We created seasonal resource selection functions (RSF) for wolves and modeled the relationship between moose first-passage time (FPT), a method that discerns alterations in movement rates, and wolf RSF values. Larger FPT values suggest rest/foraging, whereas shorter FPT values indicate travel/fleeing. We found that the movements of moose and wolves peaked at similar times of day in both study areas. Moose FPTs were 45% lower in areas most selected for by wolves relative to those avoided. The relationship between wolf RSF and moose FPT was nonlinear and varied seasonally. Differences in FPT between low and high RSF values were greatest in winter (-82.1%) and spring (-57.6%) in northeastern Minnesota and similar for all seasons in the Voyageurs National Park ecosystem. In northeastern Minnesota, where moose comprise a larger percentage of wolf diet, the relationship between moose FPT and wolf RSF was more pronounced (ave. across seasons: -60.1%) than the Voyageurs National Park ecosystem (-30.4%). These findings highlight the role wolves can play in determining moose behavior, whereby moose spend less time in areas with higher predicted likelihood of wolf resource selection.
Collapse
Affiliation(s)
- Mark A. Ditmer
- Conservation DepartmentMinnesota ZooApple ValleyMinnesota
- Department of Fisheries, Wildlife, and Conservation BiologyUniversity of MinnesotaSt. PaulMinnesota
| | - John R. Fieberg
- Department of Fisheries, Wildlife, and Conservation BiologyUniversity of MinnesotaSt. PaulMinnesota
| | - Ron A. Moen
- Department of BiologyNatural Resources Research InstituteUniversity of Minnesota DuluthDuluthMinnesota
| | | | - Seth P. Stapleton
- Conservation DepartmentMinnesota ZooApple ValleyMinnesota
- Department of Fisheries, Wildlife, and Conservation BiologyUniversity of MinnesotaSt. PaulMinnesota
| | - Tara R. Harris
- Conservation DepartmentMinnesota ZooApple ValleyMinnesota
- Department of Fisheries, Wildlife, and Conservation BiologyUniversity of MinnesotaSt. PaulMinnesota
| |
Collapse
|
7
|
Female breeding dispersal in wolverines, a solitary carnivore with high territorial fidelity. EUR J WILDLIFE RES 2018. [DOI: 10.1007/s10344-018-1164-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
8
|
O'Neil ST, Bump JK, Beyer DE. Spatially varying density dependence drives a shifting mosaic of survival in a recovering apex predator ( Canis lupus). Ecol Evol 2017; 7:9518-9530. [PMID: 29187986 PMCID: PMC5696399 DOI: 10.1002/ece3.3463] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/24/2017] [Accepted: 08/31/2017] [Indexed: 11/06/2022] Open
Abstract
Understanding landscape patterns in mortality risk is crucial for promoting recovery of threatened and endangered species. Humans affect mortality risk in large carnivores such as wolves (Canis lupus), but spatiotemporally varying density dependence can significantly influence the landscape of survival. This potentially occurs when density varies spatially and risk is unevenly distributed. We quantified spatiotemporal sources of variation in survival rates of gray wolves (C. lupus) during a 21‐year period of population recovery in the Upper Peninsula of Michigan, USA. We focused on mapping risk across time using Cox Proportional Hazards (CPH) models with time‐dependent covariates, thus exploring a shifting mosaic of survival. Extended CPH models and time‐dependent covariates revealed influences of seasonality, density dependence and experience, as well as individual‐level factors and landscape predictors of risk. We used results to predict the shifting landscape of risk at the beginning, middle, and end of the wolf recovery time series. Survival rates varied spatially and declined over time. Long‐term change was density‐dependent, with landscape predictors such as agricultural land cover and edge densities contributing negatively to survival. Survival also varied seasonally and depended on individual experience, sex, and resident versus transient status. The shifting landscape of survival suggested that increasing density contributed to greater potential for human conflict and wolf mortality risk. Long‐term spatial variation in key population vital rates is largely unquantified in many threatened, endangered, and recovering species. Variation in risk may indicate potential for source‐sink population dynamics, especially where individuals preemptively occupy suitable territories, which forces new individuals into riskier habitat types as density increases. We encourage managers to explore relationships between adult survival and localized changes in population density. Density‐dependent risk maps can identify increasing conflict areas or potential habitat sinks which may persist due to high recruitment in adjacent habitats.
Collapse
Affiliation(s)
- Shawn T O'Neil
- School of Forest Resources and Environmental Science Michigan Technological University Houghton MI USA.,Present address: U.S. Geological Survey Western Ecological Research Center 800 Business Park Dr. Suite D Dixon CA, 95620
| | - Joseph K Bump
- Department of Fisheries, Wildlife and Conservation Biology University of Minnesota St. Paul MN USA
| | - Dean E Beyer
- School of Forest Resources and Environmental Science Michigan Technological University Houghton MI USA.,Wildlife Division Michigan Department of Natural Resources Marquette MI USA
| |
Collapse
|
9
|
Uboni A, Smith DW, Stahler DR, Vucetich JA. Selecting habitat to what purpose? The advantage of exploring the habitat–fitness relationship. Ecosphere 2017. [DOI: 10.1002/ecs2.1705] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Alessia Uboni
- School of Forest Resources and Environmental Science Michigan Technological University 1400 Townsend Dr. Houghton Michigan 49931 USA
| | - Douglas W. Smith
- Yellowstone Center for Resources Wolf Project PO Box 168 Yellowstone National Park Wyoming 82190 USA
| | - Daniel R. Stahler
- Yellowstone Center for Resources Wolf Project PO Box 168 Yellowstone National Park Wyoming 82190 USA
| | - John A. Vucetich
- School of Forest Resources and Environmental Science Michigan Technological University 1400 Townsend Dr. Houghton Michigan 49931 USA
| |
Collapse
|
10
|
Dick D, Ayllón D. FloMan-MF: Floodplain Management for the Moor Frog − a simulation model for amphibian conservation in dynamic wetlands. Ecol Modell 2017. [DOI: 10.1016/j.ecolmodel.2017.01.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
11
|
Pape R, Löffler J. Seasonality of habitat selection shown to buffer alpine reindeer pastoralism against climate variability. Ecosphere 2015. [DOI: 10.1890/es15-00169.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
12
|
Uboni A, Smith DW, Mao JS, Stahler DR, Vucetich JA. Long‐ and short‐term temporal variability in habitat selection of a top predator. Ecosphere 2015. [DOI: 10.1890/es14-00419.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Alessia Uboni
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931 USA
| | - Douglas W. Smith
- Yellowstone Center for Resources, Wolf Project, P.O. Box 168, Yellowstone National Park, Wyoming 82190 USA
| | - Julie S. Mao
- Colorado Parks and Wildlife, 0088 Wildlife Way, Glenwood Springs, Colorado 81601 USA
| | - Daniel R. Stahler
- Yellowstone Center for Resources, Wolf Project, P.O. Box 168, Yellowstone National Park, Wyoming 82190 USA
| | - John A. Vucetich
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931 USA
| |
Collapse
|