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Enns GE, Jex B, Boyce MS. Diverse migration patterns and seasonal habitat use of Stone's sheep ( Ovis dalli stonei). PeerJ 2023; 11:e15215. [PMID: 37342360 PMCID: PMC10278595 DOI: 10.7717/peerj.15215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 03/20/2023] [Indexed: 06/22/2023] Open
Abstract
We describe temporal and spatial patterns of seasonal space-use and migration by 16 GPS-collared Stone's sheep (Ovis dalli stonei) from nine bands in the Cassiar Mountains of northern British Columbia, Canada. Our objectives were to identify the timing of spring and fall migrations, characterize summer and winter ranges, map and describe migration routes and use of stopover sites, and document altitudinal change across seasons. Our last objective was to assess individual migration strategies based on patterns of geographic migration, altitudinal migration, or residency. Median start and end dates of the spring migration were 12 and 17 Jun (range: 20 May to 05 Aug), and of the fall migration were 30 Aug and 22 Sep (range: 21 Aug to 07 Jan). The median area of winter and summer ranges for geographic migrants were 630.8 ha and 2,829.0 ha, respectively, with a broad range from about 233.6 to 10,196.2 ha. Individuals showed high fidelity to winter ranges over the limited duration of the study. The winter and summer ranges of most individuals (n = 15) were at moderate to high elevations with a median summer elevation of 1,709 m (1,563-1,827 m) and 1,673 m (1,478-1,751 m) that varied <150 m between ranges. Almost all collared females (n = 14) exhibited changes in elevation use that coincide with abbreviated altitudinal migration. Specifically, these females descended to lower spring elevations from their winter range (Δ > 150 m), and then gradually moved up to higher-elevation summer ranges (Δ > 150 m). In the fall, they descended to lower elevations (Δ > 100 m) before returning to their higher winter ranges. The median distance travelled along geographic migration routes was 16.3 km (range: 7.6-47.4 km). During the spring migration, most geographic migrants (n = 8) used at least one stopover site (median = 1.5, range: 0-4), while almost all migrants (n = 11) used stopover sites more frequently in the fall (median = 2.5, range: 0-6). Of the 13 migratory individuals that had at least one other collared individual in their band, most migrated at about the same time, occupied the same summer and winter ranges, used similar migration routes and stopover sites, and exhibited the same migration strategy. We found collared females exhibited four different migration strategies which mostly varied across bands. Migration strategies included long-distance geographic migrants (n = 5), short-distance geographic migrants (n = 5), vacillating migrants (n = 2), and abbreviated altitudinal migrants (n = 4). Different migratory strategies occurred within one band where one collared individual migrated and two did not. We conclude that female Stone's sheep in the Cassiar Mountains displayed a diverse assemblage of seasonal habitat use and migratory behaviors. By delineating seasonal ranges, migration routes and stopover sites, we identify potential areas of priority that can help inform land-use planning and preserve the native migrations of Stone's sheep in the region.
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Affiliation(s)
- Grace E. Enns
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- WSP Canada, Calgary, Alberta, Canada
| | - Bill Jex
- Fish & Wildlife Branch, British Columbia Ministry of Forests, Smithers, British Columbia, Canada
| | - Mark S. Boyce
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
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2
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Sergeant CJ, Sexton EK, Moore JW, Westwood AR, Nagorski SA, Ebersole JL, Chambers DM, O'Neal SL, Malison RL, Hauer FR, Whited DC, Weitz J, Caldwell J, Capito M, Connor M, Frissell CA, Knox G, Lowery ED, Macnair R, Marlatt V, McIntyre JK, McPhee MV, Skuce N. Risks of mining to salmonid-bearing watersheds. SCIENCE ADVANCES 2022; 8:eabn0929. [PMID: 35776798 PMCID: PMC10883362 DOI: 10.1126/sciadv.abn0929] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Mining provides resources for people but can pose risks to ecosystems that support cultural keystone species. Our synthesis reviews relevant aspects of mining operations, describes the ecology of salmonid-bearing watersheds in northwestern North America, and compiles the impacts of metal and coal extraction on salmonids and their habitat. We conservatively estimate that this region encompasses nearly 4000 past producing mines, with present-day operations ranging from small placer sites to massive open-pit projects that annually mine more than 118 million metric tons of earth. Despite impact assessments that are intended to evaluate risk and inform mitigation, mines continue to harm salmonid-bearing watersheds via pathways such as toxic contaminants, stream channel burial, and flow regime alteration. To better maintain watershed processes that benefit salmonids, we highlight key windows during the mining governance life cycle for science to guide policy by more accurately accounting for stressor complexity, cumulative effects, and future environmental change.
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Affiliation(s)
- Christopher J Sergeant
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, AK 99801, USA
| | - Erin K Sexton
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
| | - Jonathan W Moore
- Earth2Ocean Research Group, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Alana R Westwood
- School for Resource and Environmental Studies, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Sonia A Nagorski
- Environmental Science Program, University of Alaska Southeast, Juneau, AK 99801, USA
| | | | - David M Chambers
- Center for Science in Public Participation, Bozeman, MT 59715, USA
| | - Sarah L O'Neal
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA 98105, USA
| | - Rachel L Malison
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
| | - F Richard Hauer
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
| | - Diane C Whited
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
| | - Jill Weitz
- Salmon Beyond Borders, Juneau, AK 99801, USA
| | - Jackie Caldwell
- Lands, Resources, and Fisheries, Taku River Tlingit First Nation, Atlin, BC V0W 1A0, Canada
| | | | - Mark Connor
- Lands, Resources, and Fisheries, Taku River Tlingit First Nation, Atlin, BC V0W 1A0, Canada
| | - Christopher A Frissell
- Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA
- Department of Hydrology, Salish Kootenai College, Pablo, MT 59855, USA
| | - Greg Knox
- SkeenaWild Conservation Trust, Terrace, BC V8G 1M9, Canada
| | - Erin D Lowery
- Environment, Land, and Licensing Business Unit, Seattle City Light, Seattle, WA 98104, USA
| | | | - Vicki Marlatt
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Jenifer K McIntyre
- School of the Environment, Puyallup Research and Extension Center, Washington State University, Puyallup, WA 98371, USA
| | - Megan V McPhee
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, AK 99801, USA
| | - Nikki Skuce
- Northern Confluence Initiative, Smithers, BC V0J 2N0, Canada
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3
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Sullaway GH, Shelton AO, Samhouri JF. Synchrony erodes spatial portfolios of an anadromous fish and alters availability for resource users. J Anim Ecol 2021; 90:2692-2703. [PMID: 34553382 DOI: 10.1111/1365-2656.13575] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/30/2021] [Indexed: 11/30/2022]
Abstract
Environmental forces can create spatially synchronous dynamics among nearby populations. However, increased climate variability, driven by anthropogenic climate change, will likely enhance synchrony among spatially disparate populations. Population synchrony may lead to greater fluctuations in abundance, but the consequences of population synchrony across multiple scales of biological organization, including impacts to putative competitors, dependent predators or human communities, are rarely considered in this context. Chinook salmon Oncorhynchus tshawytscha stocks distribute across the Northeast Pacific, creating spatially variable portfolios that support large ocean fisheries and marine mammal predators, such as killer whales Orcinus orca. We rely on a multi-population model that simulates Chinook salmon ocean distribution and abundance to understand spatial portfolios, or variability in abundance within and among ocean distribution regions, of Chinook salmon stocks across 17 ocean regions from Southeast Alaska to California. We found the expected positive correlation between the number of stocks in an ocean region and spatial portfolio strength; however, increased demographic synchrony eroded Chinook salmon spatial portfolios in the ocean. Moreover, we observed decreased resource availability within ocean fishery management jurisdictions but not within killer whale summer habitat. We found a strong portfolio effect across both Southern Resident and Northern Resident killer whale habitats that was relatively unaffected by increased demographic synchrony, likely a result of the large spatial area included in these habitats. However, within the areas of smaller fishing management jurisdictions we found a weakening of Chinook salmon portfolios and increased but inconsistent likelihood of low abundance years as demographic synchrony increased. We suggest that management and conservation actions that reduce spatial synchrony can enhance short-term ecosystem resilience by promoting the stabilizing effect multiple stocks have on aggregate Chinook salmon populations and overall resource availability.
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Affiliation(s)
- Genoa H Sullaway
- Lynker, under contract to Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA
| | - Andrew O Shelton
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA
| | - Jameal F Samhouri
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA
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4
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Price MHH, Moore JW, Connors BM, Wilson KL, Reynolds JD. Portfolio simplification arising from a century of change in salmon population diversity and artificial production. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13835] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael H. H. Price
- Earth to Ocean Research Group Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - Jonathan W. Moore
- Earth to Ocean Research Group Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - Brendan M. Connors
- Earth to Ocean Research Group Department of Biological Sciences Simon Fraser University Burnaby BC Canada
- Fisheries and Oceans Canada Institute of Oceans Sciences Sidney BC Canada
| | - Kyle L. Wilson
- Earth to Ocean Research Group Department of Biological Sciences Simon Fraser University Burnaby BC Canada
| | - John D. Reynolds
- Earth to Ocean Research Group Department of Biological Sciences Simon Fraser University Burnaby BC Canada
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Chasco B, Burke B, Crozier L, Zabel R. Differential impacts of freshwater and marine covariates on wild and hatchery Chinook salmon marine survival. PLoS One 2021; 16:e0246659. [PMID: 33561177 PMCID: PMC7872236 DOI: 10.1371/journal.pone.0246659] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 01/22/2021] [Indexed: 11/24/2022] Open
Abstract
Large-scale atmospheric conditions in the Northeast Pacific Ocean affect both the freshwater environment in the Columbia River Basin and marine conditions along the coasts of Oregon, Washington, and British Columbia, resulting in correlated conditions in the two environments. For migrating species, such as salmonids that move through multiple habitats, these correlations can amplify the impact of good or poor physical conditions on growth and survival, as movements among habitats may not alleviate effects of anomalous conditions. Unfortunately, identifying the mechanistic drivers of salmon survival in space and time is hindered by these cross-habitat correlations. To address this issue, we modeled the marine survival of Snake River spring/summer Chinook salmon with multiple indices of the marine environment and an explicit treatment of the effect of arrival timing from freshwater to the ocean, and found that both habitats contribute to marine survival rates. We show how this particular carryover effect of freshwater conditions on marine survival varies by year and rearing type (hatchery or wild), with a larger effect for wild fish. As environmental conditions change, incorporating effects from both freshwater and marine habitats into salmon survival models will become more important, and has the additional benefit of highlighting how management actions that affect arrival timing may improve marine survival.
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Affiliation(s)
- Brandon Chasco
- Fish Ecology Division, National Marine Fisheries Service, National Oceanic and Atmospheric Association, Newport, Oregon, United States of America
- * E-mail:
| | - Brian Burke
- Fish Ecology Division, National Marine Fisheries Service, National Oceanic and Atmospheric Association, Seattle, Washington, United States of America
| | - Lisa Crozier
- Fish Ecology Division, National Marine Fisheries Service, National Oceanic and Atmospheric Association, Seattle, Washington, United States of America
| | - Rich Zabel
- Fish Ecology Division, National Marine Fisheries Service, National Oceanic and Atmospheric Association, Seattle, Washington, United States of America
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6
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Walsworth TE, Baldock JR, Zimmerman CE, Schindler DE. Interaction between watershed features and climate forcing affects habitat profitability for juvenile salmon. Ecosphere 2020. [DOI: 10.1002/ecs2.3266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Timothy E. Walsworth
- Department of Watershed Sciences and the Ecology Center Utah State University Logan Utah84322USA
- School of Aquatic and Fishery Sciences University of Washington Seattle Washington98105USA
| | - Jeffrey R. Baldock
- School of Aquatic and Fishery Sciences University of Washington Seattle Washington98105USA
- Wyoming Cooperative Fish and Wildlife Research Unit Department of Zoology and Physiology University of Wyoming Laramie Wyoming82071USA
| | | | - Daniel E. Schindler
- School of Aquatic and Fishery Sciences University of Washington Seattle Washington98105USA
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7
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Pelletier MC, Ebersole J, Mulvaney K, Rashleigh B, Gutierrez MN, Chintala M, Kuhn A, Molina M, Bagley M, Lane C. Resilience of aquatic systems: Review and management implications. AQUATIC SCIENCES 2020; 82:1-44. [PMID: 32489242 PMCID: PMC7265686 DOI: 10.1007/s00027-020-00717-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Our understanding of how ecosystems function has changed from an equilibria-based view to one that recognizes the dynamic, fluctuating, nonlinear nature of aquatic systems. This current understanding requires that we manage systems for resilience. In this review, we examine how resilience has been defined, measured and applied in aquatic systems, and more broadly, in the socioecological systems in which they are embedded. Our review reveals the importance of managing stressors adversely impacting aquatic system resilience, as well as understanding the environmental and climatic cycles and changes impacting aquatic resources. Aquatic resilience may be enhanced by maintaining and enhancing habitat connectivity as well as functional redundancy and physical and biological diversity. Resilience in aquatic socioecological system may be enhanced by understanding and fostering linkages between the social and ecological subsystems, promoting equity among stakeholders, and understanding how the system is impacted by factors within and outside the area of immediate interest. Management for resilience requires implementation of adaptive and preferably collaborative management. Implementation of adaptive management for resilience will require an effective monitoring framework to detect key changes in the coupled socioecological system. Research is needed to (1) develop sensitive indicators and monitoring designs, (2) disentangle complex multi-scalar interactions and feedbacks, and (3) generalize lessons learned across aquatic ecosystems and apply them in new contexts.
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Affiliation(s)
- Marguerite C Pelletier
- Office of Research and Development, Center for Environmental Measurement and Modeling, Atlantic Coastal Environmental Sciences Division, U.S. Environmental Protection Agency, Narragansett, RI, USA
| | - Joe Ebersole
- Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecology Division, U.S. Environmental Protection Agency, Corvallis, OR, USA
| | - Kate Mulvaney
- Office of Research and Development, Center for Environmental Measurement and Modeling, Atlantic Coastal Environmental Sciences Division, U.S. Environmental Protection Agency, Narragansett, RI, USA
| | - Brenda Rashleigh
- Office of Research and Development, Center for Public Health and Environmental Assessment, U.S. Environmental Protection Agency, Narragansett, RI, USA
| | | | - Marnita Chintala
- Office of Research and Development, Center for Environmental Measurement and Modeling, Atlantic Coastal Environmental Sciences Division, U.S. Environmental Protection Agency, Narragansett, RI, USA
| | - Anne Kuhn
- Office of Research and Development, Center for Environmental Measurement and Modeling, Atlantic Coastal Environmental Sciences Division, U.S. Environmental Protection Agency, Narragansett, RI, USA
| | - Marirosa Molina
- Office of Research and Development, Center for Environmental Measurement and Modeling, Watershed and Ecosystem Characterization Division, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Mark Bagley
- Office of Research and Development, Center for Environmental Measurement and Modeling, Watershed and Ecosystem Characterization Division, U.S. Environmental Protection Agency, Cincinnati, OH, USA
| | - Chuck Lane
- Office of Research and Development, Center for Environmental Measurement and Modeling, Watershed and Ecosystem Characterization Division, U.S. Environmental Protection Agency, Cincinnati, OH, USA
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8
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Sturrock AM, Carlson SM, Wikert JD, Heyne T, Nusslé S, Merz JE, Sturrock HJW, Johnson RC. Unnatural selection of salmon life histories in a modified riverscape. GLOBAL CHANGE BIOLOGY 2020; 26:1235-1247. [PMID: 31789453 PMCID: PMC7277499 DOI: 10.1111/gcb.14896] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 09/29/2019] [Indexed: 05/26/2023]
Abstract
Altered river flows and fragmented habitats often simplify riverine communities and favor non-native fishes, but their influence on life-history expression and survival is less clear. Here, we quantified the expression and ultimate success of diverse salmon emigration behaviors in an anthropogenically altered California river system. We analyzed two decades of Chinook salmon monitoring data to explore the influence of regulated flows on juvenile emigration phenology, abundance, and recruitment. We then followed seven cohorts into adulthood using otolith (ear stone) chemical archives to identify patterns in time- and size-selective mortality along the migratory corridor. Suppressed winter flow cues were associated with delayed emigration timing, particularly in warm, dry years, which was also when selection against late migrants was the most extreme. Lower, less variable flows were also associated with reduced juvenile and adult production, highlighting the importance of streamflow for cohort success in these southernmost populations. While most juveniles emigrated from the natal stream as fry or smolts, the survivors were dominated by the rare few that left at intermediate sizes and times, coinciding with managed flows released before extreme summer temperatures. The consistent selection against early (small) and late (large) migrants counters prevailing ecological theory that predicts different traits to be favored under varying environmental conditions. Yet, even with this weakened portfolio, maintaining a broad distribution in migration traits still increased adult production and reduced variance. In years exhibiting large fry pulses, even marginal increases in their survival would have significantly boosted recruitment. However, management actions favoring any single phenotype could have negative evolutionary and demographic consequences, potentially reducing adaptability and population stability. To recover fish populations and support viable fisheries in a warming and increasingly unpredictable climate, coordinating flow and habitat management within and among watersheds will be critical to balance trait optimization versus diversification.
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Affiliation(s)
- Anna M. Sturrock
- Center for Watershed SciencesUniversity of California, DavisDavisCAUSA
| | - Stephanie M. Carlson
- Department of Environmental Science, Policy, and ManagementUniversity of California, BerkeleyBerkeleyCAUSA
| | | | - Tim Heyne
- California Department of Fish and WildlifeLa GrangeCAUSA
| | - Sébastien Nusslé
- Department of Environmental Science, Policy, and ManagementUniversity of California, BerkeleyBerkeleyCAUSA
| | - Joseph E. Merz
- Institute of Marine SciencesUniversity of California Santa CruzSanta CruzCAUSA
- Cramer Fish SciencesWest SacramentoCAUSA
| | - Hugh J. W. Sturrock
- Department of Epidemiology & BiostatisticsUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Rachel C. Johnson
- Center for Watershed SciencesUniversity of California, DavisDavisCAUSA
- Fisheries Ecology DivisionSouthwest Fisheries Science CenterNational Marine Fisheries ServiceSanta CruzCAUSA
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9
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Freshwater C, Anderson SC, Holt KR, Huang A, Holt CA. Weakened portfolio effects constrain management effectiveness for population aggregates. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01966. [PMID: 31257710 PMCID: PMC6900020 DOI: 10.1002/eap.1966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/24/2019] [Accepted: 06/14/2019] [Indexed: 06/09/2023]
Abstract
Population diversity can reduce temporal variability in aggregate population abundances in a process known as the portfolio effect. Portfolio effects may weaken, however, due to greater synchrony among component populations. While weakened portfolio effects have been previously documented, the consequences of reduced stability on meeting conservation goals for population aggregates that are harvested (e.g., stock aggregates in fisheries) are rarely quantified. Here, we demonstrate how changes in variability within components, synchrony among components, and population productivity interact to influence the probability of achieving an array of management objectives for Fraser River sockeye salmon: a stock aggregate of high economic, ecological, and cultural value. We first present evidence that component variability and synchrony have increased over the last two decades, consistent with a weakening portfolio effect. We then parameterize a stochastic, closed-loop model that simulates the population dynamics of each stock, the fishery that harvests the stock aggregate, and the management framework used to establish mixed-stock exploitation rates. We find that while median aggregate abundance and catch through time were relatively insensitive to greater aggregate variability, catch stability and performance metrics associated with achieving management targets generally declined as component variability and synchrony increased. A notable exception we observed is that harvest control means that scale exploitation rates based on aggregate abundance may be more effective as synchrony increases. Reductions in productivity led to broad declines in performance, but also moderated the impacts of component variability and synchrony on the proportion of component stocks above management targets and catch stability. Our results suggest that even precautionary management strategies that account for declines in productivity may underestimate risk, particularly to socioeconomic objectives, if they fail to consider changes in aggregate variability. Adequately incorporating changes in portfolio effect strength may be particularly relevant when developing recovery strategies that are robust to climate change, which is likely to increase synchrony and component variability.
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Affiliation(s)
- Cameron Freshwater
- Fisheries and Oceans CanadaPacific Biological Station3190 Hammond Bay RoadNanaimoBritish ColumbiaV9T 6N7Canada
| | - Sean C. Anderson
- Fisheries and Oceans CanadaPacific Biological Station3190 Hammond Bay RoadNanaimoBritish ColumbiaV9T 6N7Canada
| | - Kendra R. Holt
- Fisheries and Oceans CanadaInstitute of Ocean Sciences9860 West Saanich RoadSidneyBritish ColumbiaV8L 5T5Canada
| | - Ann‐Marie Huang
- Fisheries and Oceans CanadaPacific Biological Station3190 Hammond Bay RoadNanaimoBritish ColumbiaV9T 6N7Canada
| | - Carrie A. Holt
- Fisheries and Oceans CanadaPacific Biological Station3190 Hammond Bay RoadNanaimoBritish ColumbiaV9T 6N7Canada
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10
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Lowrey B, Proffitt KM, McWhirter DE, White PJ, Courtemanch AB, Dewey SR, Miyasaki HM, Monteith KL, Mao JS, Grigg JL, Butler CJ, Lula ES, Garrott RA. Characterizing population and individual migration patterns among native and restored bighorn sheep ( Ovis canadensis). Ecol Evol 2019; 9:8829-8839. [PMID: 31410283 PMCID: PMC6686647 DOI: 10.1002/ece3.5435] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/19/2019] [Accepted: 06/08/2019] [Indexed: 01/20/2023] Open
Abstract
Migration evolved as a behavior to enhance fitness through exploiting spatially and temporally variable resources and avoiding predation or other threats. Globally, landscape alterations have resulted in declines to migratory populations across taxa. Given the long time periods over which migrations evolved in native systems, it is unlikely that restored populations embody the same migratory complexity that existed before population reductions or regional extirpation.We used GPS location data collected from 209 female bighorn sheep (Ovis canadensis) to characterize population and individual migration patterns along elevation and geographic continuums for 18 populations of bighorn sheep with different management histories (i.e., restored, augmented, and native) across the western United States.Individuals with resident behaviors were present in all management histories. Elevational migrations were the most common population-level migratory behavior. There were notable differences in the degree of individual variation within a population across the three management histories. Relative to native populations, restored and augmented populations had less variation among individuals with respect to elevation and geographic migration distances. Differences in migratory behavior were most pronounced for geographic distances, where the majority of native populations had a range of variation that was 2-4 times greater than restored or augmented populations. Synthesis and applications. Migrations within native populations include a variety of patterns that translocation efforts have not been able to fully recreate within restored and augmented populations. Theoretical and empirical research has highlighted the benefits of migratory diversity in promoting resilience and population stability. Limited migratory diversity may serve as an additional factor limiting demographic performance and range expansion. We suggest preserving native systems with intact migratory portfolios and a more nuanced approach to restoration and augmentation in which source populations are identified based on a suite of criteria that includes matching migratory patterns of source populations with local landscape attributes.
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Affiliation(s)
- Blake Lowrey
- Fish and Wildlife Ecology and Management Program, Department of EcologyMontana State UniversityBozemanMTUSA
| | | | | | - Patrick J. White
- Yellowstone Center for Resources, Yellowstone National ParkNational Park ServiceMammothWYUSA
| | | | | | | | - Kevin L. Monteith
- Haub School of Environment and Natural Resources, Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and PhysiologyUniversity of WyomingLaramieWYUSA
| | - Julie S. Mao
- Colorado Parks and WildlifeGlenwood SpringsCOUSA
| | | | | | - Ethan S. Lula
- Fish and Wildlife Ecology and Management Program, Department of EcologyMontana State UniversityBozemanMTUSA
| | - Robert A. Garrott
- Fish and Wildlife Ecology and Management Program, Department of EcologyMontana State UniversityBozemanMTUSA
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11
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Matthies BD, Jacobsen JB, Knoke T, Paul C, Valsta L. Utilising portfolio theory in environmental research - New perspectives and considerations. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 231:926-939. [PMID: 30602254 DOI: 10.1016/j.jenvman.2018.10.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 09/22/2018] [Accepted: 10/14/2018] [Indexed: 06/09/2023]
Abstract
Modern Portfolio Theory is a well-established method in economic research for considering the risks and returns in asset allocations and the potential benefits of diversification for risk averse agents. Thus, it is a useful tool for guiding sustainability discourse under uncertain future states. Existing discussions around the method's use in environmental research have evolved during over the 75 years of its application, leading to a continued renewal of perspectives on utilising it. We classify the environmental questions where portfolio theory has been applied, and critically discuss the methodological approaches taken; providing a stepping stone for future use of the method. This article provides a framework for its application in environmental research using the following questions: 1) what is the type of research or management question and objective(s) of the decision-maker(s); 2) what are the definitions of the assets to be included in the portfolio; 3) what are the ways that returns are valued, discounted, distributed and weighted; 4) what is the most appropriate way for risks to be accounted for and managed, including the selection of the appropriate model and taking into account risk preferences; and 5) what are the definitions of constraints in the programming problem.
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Affiliation(s)
- Brent D Matthies
- Helsinki Institute of Sustainability Science, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27 (Latokartaanonkaari 7), 00014, Helsinki, Finland; Dasos Capital Oy, Itämerentori 2, 00180, Helsinki, Finland.
| | - Jette Bredahl Jacobsen
- Section for Environment and Natural Resources, Rolighedsvej 23, 1958 Frb. C, Old Building Living Room, Building: A107, Copenhagen, Denmark.
| | - Thomas Knoke
- Institute of Forest Management, Hans-Carl-von-Carlowitz-Platz 2, 85354, Freising, Germany.
| | - Carola Paul
- Department of Forest Economics and Forest Management, Georg-August-University Goettingen, Busway 3, 37077, Göttingen, Germany.
| | - Lauri Valsta
- Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27 (Latokartaanonkaari 7), 00014, Helsinki, Finland.
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12
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DeFilippo LB, Schindler DE, Ohlberger J, Schaberg KL, Foster MB, Ruhl D, Punt AE. Recruitment variation disrupts the stability of alternative life histories in an exploited salmon population. Evol Appl 2019; 12:214-229. [PMID: 30697335 PMCID: PMC6346651 DOI: 10.1111/eva.12709] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/14/2018] [Accepted: 08/23/2018] [Indexed: 11/26/2022] Open
Abstract
Males of many fish species exhibit alternative reproductive tactics, which can influence the maturation schedules, fishery productivity, and resilience to harvest of exploited populations. While alternative mating phenotypes can persist in stable equilibria through frequency-dependent selection, shifts in tactic frequencies have been observed and can have substantial consequences for fisheries. Here, we examine the dynamics of precocious sneaker males called "jacks" in a population of sockeye salmon (Oncorhynchus nerka) from Frazer Lake, Alaska. Jacks, which are of little commercial value due to their small body sizes, have recently been observed at unusually high levels in this stock, degrading the value of regional fisheries. To inform future strategies for managing the prevalence of jacks, we used long-term monitoring data to identify what regulates the frequencies of alternative male phenotypes in the population over time. Expression of the jack life history could not be explained by environmental factors expected to influence juvenile body condition and maturation probability. Instead, we found a strong positive association between the proportion of individuals maturing as jacks within a cohort and the prevalence of jacks among the males that sired that cohort. Moreover, due to differences in age-at-maturity between male phenotypes, and large interannual variability in recruitment strength, jacks from strong year-classes often spawn among older males from the weaker recruitments of earlier cohorts. Through such "cohort mismatches," which are amplified by size-selective harvest on older males, jacks frequently achieve substantial representation in the breeding population, and likely high total fertilizations. The repeated occurrence of these cohort mismatches appears to disrupt the stabilizing influence of frequency-dependent selection, allowing the prevalence of jacks to exceed what might be expected under equilibrium conditions. These results emphasize that the dynamics of alternative life histories can profoundly influence fishery performance and should be explicitly considered in the management of exploited populations.
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Affiliation(s)
- Lukas B. DeFilippo
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashington
| | - Daniel E. Schindler
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashington
| | - Jan Ohlberger
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashington
| | - Kevin L. Schaberg
- Alaska Department of Fish and GameDivision of Commercial Fisheries Westward Region OfficeKodiakAlaska
| | - Matt Birch Foster
- Alaska Department of Fish and GameDivision of Commercial Fisheries Westward Region OfficeKodiakAlaska
| | - Darin Ruhl
- Alaska Department of Fish and GameDivision of Commercial Fisheries Westward Region OfficeKodiakAlaska
| | - André E. Punt
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashington
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13
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Cunningham CJ, Westley PAH, Adkison MD. Signals of large scale climate drivers, hatchery enhancement, and marine factors in Yukon River Chinook salmon survival revealed with a Bayesian life history model. GLOBAL CHANGE BIOLOGY 2018; 24:4399-4416. [PMID: 29774975 DOI: 10.1111/gcb.14315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 02/26/2018] [Accepted: 04/07/2018] [Indexed: 05/24/2023]
Abstract
Understanding how species might respond to climate change involves disentangling the influence of co-occurring environmental factors on population dynamics, and is especially problematic for migratory species like Pacific salmon that move between ecosystems. To date, debate surrounding the causes of recent declines in Yukon River Chinook salmon (Oncorhynchus tshawytscha) abundance has centered on whether factors in freshwater or marine environments control variation in survival, and how these populations at the northern extremity of the species range will respond to climate change. To estimate the effect of factors in marine and freshwater environments on Chinook salmon survival, we constructed a stage-structured assessment model that incorporates the best available data, estimates incidental marine bycatch mortality in trawl fisheries, and uses Bayesian model selection methods to quantify support for alternative hypotheses. Models fitted to two index populations of Yukon River Chinook salmon indicate that processes in the nearshore and marine environments are the most important determinants of survival. Specifically, survival declines when ice leaves the Yukon River later in the spring, increases with wintertime temperature in the Bering Sea, and declines with the abundance of globally enhanced salmon species consistent with competition at sea. In addition, we found support for density-dependent survival limitations in freshwater but not marine portions of the life cycle, increasing average survival with ocean age, and age-specific selectivity of bycatch mortality in the Bering Sea. This study underscores the utility of flexible estimation models capable of fitting multiple data types and evaluating mortality from both natural and anthropogenic sources in multiple habitats. Overall, these analyses suggest that mortality at sea is the primary driver of population dynamics, yet under warming climate Chinook salmon populations at the northern extent of the species' range may be expected to fare better than southern populations, but are influenced by foreign salmon production.
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Affiliation(s)
- Curry J Cunningham
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska
| | - Peter A H Westley
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska
| | - Milo D Adkison
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska
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14
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Terui A, Ishiyama N, Urabe H, Ono S, Finlay JC, Nakamura F. Metapopulation stability in branching river networks. Proc Natl Acad Sci U S A 2018; 115:E5963-E5969. [PMID: 29895695 PMCID: PMC6042068 DOI: 10.1073/pnas.1800060115] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intraspecific population diversity (specifically, spatial asynchrony of population dynamics) is an essential component of metapopulation stability and persistence in nature. In 2D systems, theory predicts that metapopulation stability should increase with ecosystem size (or habitat network size): Larger ecosystems will harbor more diverse subpopulations with more stable aggregate dynamics. However, current theories developed in simplified landscapes may be inadequate to predict emergent properties of branching ecosystems, an overlooked but widespread habitat geometry. Here, we combine theory and analyses of a unique long-term dataset to show that a scale-invariant characteristic of fractal river networks, branching complexity (measured as branching probability), stabilizes watershed metapopulations. In riverine systems, each branch (i.e., tributary) exhibits distinctive ecological dynamics, and confluences serve as "merging" points of those branches. Hence, increased levels of branching complexity should confer a greater likelihood of integrating asynchronous dynamics over the landscape. We theoretically revealed that the stabilizing effect of branching complexity is a consequence of purely probabilistic processes in natural conditions, where within-branch synchrony exceeds among-branch synchrony. Contrary to current theories developed in 2D systems, metapopulation size (a variable closely related to ecosystem size) had vague effects on metapopulation stability. These theoretical predictions were supported by 18-y observations of fish populations across 31 watersheds: Our cross-watershed comparisons revealed consistent stabilizing effects of branching complexity on metapopulations of very different riverine fishes. A strong association between branching complexity and metapopulation stability is likely to be a pervasive feature of branching networks that strongly affects species persistence during rapid environmental changes.
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Affiliation(s)
- Akira Terui
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108;
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
| | - Nobuo Ishiyama
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
| | - Hirokazu Urabe
- Salmon and Freshwater Fisheries Research Institute, Hokkaido Research Organization, 061-1433 Eniwa, Japan
| | - Satoru Ono
- Institute of Environmental Sciences, Hokkaido Research Organization, 060-0819 Sapporo, Japan
| | - Jacques C Finlay
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108
| | - Futoshi Nakamura
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
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15
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Chasco BE, Kaplan IC, Thomas AC, Acevedo-Gutiérrez A, Noren DP, Ford MJ, Hanson MB, Scordino JJ, Jeffries SJ, Marshall KN, Shelton AO, Matkin C, Burke BJ, Ward EJ. Competing tradeoffs between increasing marine mammal predation and fisheries harvest of Chinook salmon. Sci Rep 2017; 7:15439. [PMID: 29158502 PMCID: PMC5696463 DOI: 10.1038/s41598-017-14984-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/16/2017] [Indexed: 11/09/2022] Open
Abstract
Many marine mammal predators, particularly pinnipeds, have increased in abundance in recent decades, generating new challenges for balancing human uses with recovery goals via ecosystem-based management. We used a spatio-temporal bioenergetics model of the Northeast Pacific Ocean to quantify how predation by three species of pinnipeds and killer whales (Orcinus orca) on Chinook salmon (Oncorhynchus tshawytscha) has changed since the 1970s along the west coast of North America, and compare these estimates to salmon fisheries. We find that from 1975 to 2015, biomass of Chinook salmon consumed by pinnipeds and killer whales increased from 6,100 to 15,200 metric tons (from 5 to 31.5 million individual salmon). Though there is variation across the regions in our model, overall, killer whales consume the largest biomass of Chinook salmon, but harbor seals (Phoca vitulina) consume the largest number of individuals. The decrease in adult Chinook salmon harvest from 1975-2015 was 16,400 to 9,600 metric tons. Thus, Chinook salmon removals (harvest + consumption) increased in the past 40 years despite catch reductions by fisheries, due to consumption by recovering pinnipeds and endangered killer whales. Long-term management strategies for Chinook salmon will need to consider potential conflicts between rebounding predators or endangered predators and prey.
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Affiliation(s)
- Brandon E Chasco
- Contractor to Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA. .,Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, 97331, USA.
| | - Isaac C Kaplan
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
| | - Austen C Thomas
- Smith-Root, Research Division, 16603 NE, 50th Avenue, Vancouver, WA, 98686, USA
| | | | - Dawn P Noren
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
| | - Michael J Ford
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
| | - M Bradley Hanson
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
| | | | | | - Kristin N Marshall
- Fishery Resource Analysis and Monitoring Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98117, USA
| | - Andrew O Shelton
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
| | - Craig Matkin
- North Gulf Oceanic Society, 3430 Main St. Suite B1, Homer, Alaska, 99603, USA
| | - Brian J Burke
- Fish Ecology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98117, USA
| | - Eric J Ward
- Conservation Biology Division, NOAA NMFS Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725, Montlake Blvd. East, Seattle, WA, 98112, USA
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16
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Yamane L, Botsford LW, Kilduff DP. Tracking restoration of population diversity via the portfolio effect. J Appl Ecol 2017. [DOI: 10.1111/1365-2664.12978] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lauren Yamane
- Department of Wildlife, Fish, and Conservation Biology; University of California, Davis; Davis CA USA
| | - Louis W. Botsford
- Department of Wildlife, Fish, and Conservation Biology; University of California, Davis; Davis CA USA
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17
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Shah P, Mallory ML, Ando AW, Guntenspergen GR. Fine-resolution conservation planning with limited climate-change information. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2017; 31:278-289. [PMID: 27346847 DOI: 10.1111/cobi.12793] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 06/18/2016] [Accepted: 06/22/2016] [Indexed: 06/06/2023]
Abstract
Climate-change induced uncertainties in future spatial patterns of conservation-related outcomes make it difficult to implement standard conservation-planning paradigms. A recent study translates Markowitz's risk-diversification strategy from finance to conservation settings, enabling conservation agents to use this diversification strategy for allocating conservation and restoration investments across space to minimize the risk associated with such uncertainty. However, this method is information intensive and requires a large number of forecasts of ecological outcomes associated with possible climate-change scenarios for carrying out fine-resolution conservation planning. We developed a technique for iterative, spatial portfolio analysis that can be used to allocate scarce conservation resources across a desired level of subregions in a planning landscape in the absence of a sufficient number of ecological forecasts. We applied our technique to the Prairie Pothole Region in central North America. A lack of sufficient future climate information prevented attainment of the most efficient risk-return conservation outcomes in the Prairie Pothole Region. The difference in expected conservation returns between conservation planning with limited climate-change information and full climate-change information was as large as 30% for the Prairie Pothole Region even when the most efficient iterative approach was used. However, our iterative approach allowed finer resolution portfolio allocation with limited climate-change forecasts such that the best possible risk-return combinations were obtained. With our most efficient iterative approach, the expected loss in conservation outcomes owing to limited climate-change information could be reduced by 17% relative to other iterative approaches.
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Affiliation(s)
- Payal Shah
- Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa, 904-0495, Japan
| | - Mindy L Mallory
- Department of Agricultural and Consumer Economics, University of Illinois at Urbana Champaign, Urbana, IL, 61801, U.S.A
| | - Amy W Ando
- Department of Agricultural and Consumer Economics, University of Illinois at Urbana Champaign, Urbana, IL, 61801, U.S.A
- Resources for the Future, Washington, D.C., 20036, U.S.A
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18
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Brennan SR, Schindler DE. Linking otolith microchemistry and dendritic isoscapes to map heterogeneous production of fish across river basins. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2017; 27:363-377. [PMID: 27875020 DOI: 10.1002/eap.1474] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/22/2016] [Accepted: 11/02/2016] [Indexed: 06/06/2023]
Abstract
Production patterns of highly mobile species, such as anadromous fish, often exhibit high spatial and temporal heterogeneity across landscapes. Such variability is often asynchronous in time among habitats, which stabilizes production at aggregate scales of complexity. Reconstructing production patterns explicitly in space and time across multiple scales, however, remains difficult but is important for prioritizing habitat conservation. This is especially true for fishes inhabiting river basins due to long-range dispersal, high mortality at early life stages, complex population structure and elusive life history variation. We develop a new approach for mapping production patterns of Pacific salmon across a large river basin by integrating otolith microchemistry and dendritic isoscape models. The geographically continuous Bayesian assignment framework presented here yielded high accuracies (>90%) and relatively high precisions (precisions <4%; i.e., assignment areas of <530 river km of the 13 100 km total river length) when used to determine the natal source of known-origin juvenile Chinook salmon captured throughout the study region. Integrating these methods enabled us to base estimates of provenance and habitat use of individuals on a per location basis using strontium isotopic data throughout the continuous spatial domain of a river network. Such a framework provides substantial advantages over the more common nominal approach to employing otolith microchemistry to reconstruct movement patterns of fish. In doing so, we reconstructed the spatial production patterns of adult Chinook salmon returning to a large watershed in Bristol Bay, Alaska and illustrate the power of such an approach to conservation efforts.
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Affiliation(s)
- Sean R Brennan
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, 98105, USA
| | - Daniel E Schindler
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, 98105, USA
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19
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Fullerton AH, Anzalone S, Moran P, Van Doornik DM, Copeland T, Zabel RW. Setting spatial conservation priorities despite incomplete data for characterizing metapopulations. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:2558-2578. [PMID: 27865061 DOI: 10.1002/eap.1411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 06/13/2016] [Accepted: 06/22/2016] [Indexed: 06/06/2023]
Abstract
Management of spatially structured species poses unique challenges. Despite a strong theoretical foundation, practitioners rarely have sufficient empirical data to evaluate how populations interact. Rather, assumptions about connectivity and source-sink dynamics are often based on incomplete, extrapolated, or modeled data, if such interactions are even considered at all. Therefore, it has been difficult to evaluate whether spatially structured species are meeting conservation goals. We evaluated how estimated metapopulation structure responded to estimates of population sizes and dispersal probabilities and to the set of populations included. We then compared outcomes of alternative management strategies that target conservation of metapopulation processes. We illustrated these concepts for Chinook salmon (Oncorhynchus tshawytscha) in the Snake River, USA. Our description of spatial structure for this metapopulation was consistent with previous characterizations. We found substantial differences in estimated metapopulation structure when we had incomplete information about all populations and when we used different sources of data (three empirical, two modeled) to estimate dispersal, whereas responses to population size estimates were more consistent. Together, these findings suggest that monitoring efforts should target all populations occasionally and populations that play key roles frequently and that multiple types of data should be collected when feasible. When empirical data are incomplete or of uneven quality, analyses using estimates produced from an ensemble of available datasets can help conservation planners and managers weigh near-term options. Doing so, we found trade-offs in connectivity and source dominance in metapopulation-level responses to alternative management strategies that suggest which types of approaches may be inherently less risky.
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Affiliation(s)
- A H Fullerton
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - S Anzalone
- University of Western Washington, 516 High Street, Bellingham, Washington, 98225, USA
| | - P Moran
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - D M Van Doornik
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - T Copeland
- Idaho Department of Fish and Game, Southwest Region, 1414 E Locust Lane, Nampa, Idaho, 83686, USA
| | - R W Zabel
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
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20
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Armstrong JB, Takimoto G, Schindler DE, Hayes MM, Kauffman MJ. Resource waves: phenological diversity enhances foraging opportunities for mobile consumers. Ecology 2016; 97:1099-112. [PMID: 27349088 DOI: 10.1890/15-0554.1] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Time can be a limiting constraint for consumers, particularly when resource phenology mediates foraging opportunity. Though a large body of research has explored how resource phenology influences trophic interactions, this work has focused on the topics of trophic mismatch or predator swamping, which typically occur over short periods, at small spatial extents or coarse resolutions. In contrast many consumers integrate across landscape heterogeneity in resource phenology, moving to track ephemeral food sources that propagate across space as resource waves. Here we provide a conceptual framework to advance the study of phenological diversity and resource waves. We define resource waves, review evidence of their importance in recent case studies, and demonstrate their broader ecological significance with a simulation model. We found that consumers ranging from fig wasps (Chalcidoidea) to grizzly bears (Ursus arctos) exploit resource waves, integrating across phenological diversity to make resource aggregates available for much longer than their component parts. In model simulations, phenological diversity was often more important to consumer energy gain than resource abundance per se. Current ecosystem-based management assumes that species abundance mediates the strength of trophic interactions. Our results challenge this assumption and highlight new opportunities for conservation and management. Resource waves are an emergent property of consumer-resource interactions and are broadly significant in ecology and conservation.
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21
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Kovach RP, Luikart G, Lowe WH, Boyer MC, Muhlfeld CC. Risk and efficacy of human-enabled interspecific hybridization for climate-change adaptation: response to Hamilton and Miller (2016). CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2016; 30:428-430. [PMID: 26918487 DOI: 10.1111/cobi.12678] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 10/19/2015] [Indexed: 06/05/2023]
Affiliation(s)
- Ryan P Kovach
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Glacier National Park West Glacier, MT, 59936, U.S.A
| | - Gordon Luikart
- Flathead Lake Biological Station, University of Montana, Polson, MT, 59860, U.S.A
| | - Winsor H Lowe
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, U.S.A
| | | | - Clint C Muhlfeld
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Glacier National Park West Glacier, MT, 59936, U.S.A
- Flathead Lake Biological Station, University of Montana, Polson, MT, 59860, U.S.A
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22
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DuFour MR, May CJ, Roseman EF, Ludsin SA, Vandergoot CS, Pritt JJ, Fraker ME, Davis JJ, Tyson JT, Miner JG, Marschall EA, Mayer CM. Portfolio theory as a management tool to guide conservation and restoration of multi-stock fish populations. Ecosphere 2015. [DOI: 10.1890/es15-00237.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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23
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Changing central Pacific El Niños reduce stability of North American salmon survival rates. Proc Natl Acad Sci U S A 2015; 112:10962-6. [PMID: 26240365 DOI: 10.1073/pnas.1503190112] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable--including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions.
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24
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Truchy A, Angeler DG, Sponseller RA, Johnson RK, McKie BG. Linking Biodiversity, Ecosystem Functioning and Services, and Ecological Resilience. ADV ECOL RES 2015. [DOI: 10.1016/bs.aecr.2015.09.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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