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Defourneaux M, Barrio IC, Boulanger-Lapointe N, Speed JDM. Long-term changes in herbivore community and vegetation impact of wild and domestic herbivores across Iceland. AMBIO 2024; 53:1124-1135. [PMID: 38402492 PMCID: PMC11182994 DOI: 10.1007/s13280-024-01998-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 01/18/2024] [Accepted: 02/08/2024] [Indexed: 02/26/2024]
Abstract
Changes in wild and domestic herbivore populations significantly impact extensive grazing systems, particularly in low productive environments, where increasing wild herbivore populations are perceived as a threat to farming. To assess the magnitude of these changes in Iceland, we compiled time series on herbivore populations from 1986 to 2020 and estimated changes in species densities, metabolic biomass, and consumption of plant biomass in improved lands and unimproved rangelands. We compared estimates of consumption rates to past and present net primary production. Overall, the herbivore community composition shifted from livestock to wildlife dominated. However, wild herbivores only contributed a small fraction (14%) of the total herbivore metabolic biomass and consumption (4-7%), and livestock dominated the overall herbivore biomass. These insights highlight the necessity of developing improved local integrated management for both wild and domestic herbivores where they coexist.
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Affiliation(s)
- Mathilde Defourneaux
- Faculty of Environmental and Forest Sciences, Agricultural University of Iceland, Árleyni 22, Keldnaholt, 112, Reykjavík, Iceland.
| | - Isabel C Barrio
- Faculty of Environmental and Forest Sciences, Agricultural University of Iceland, Árleyni 22, Keldnaholt, 112, Reykjavík, Iceland
| | | | - James D M Speed
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology, 7491, Trondheim, Norway
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2
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Svenning JC, Buitenwerf R, Le Roux E. Trophic rewilding as a restoration approach under emerging novel biosphere conditions. Curr Biol 2024; 34:R435-R451. [PMID: 38714176 DOI: 10.1016/j.cub.2024.02.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2024]
Abstract
Rewilding is a restoration approach that aims to promote self-regulating complex ecosystems by restoring non-human ecological processes while reducing human control and pressures. Rewilding is forward-looking in that it aims to enhance functionality for biodiversity, accepting and indeed promoting the dynamic nature of ecosystems, rather than fixating on static composition or structure. Rewilding is thus especially relevant in our epoch of increasingly novel biosphere conditions, driven by strong human-induced global change. Here, we explore this hypothesis in the context of trophic rewilding - the restoration of trophic complexity mediated by wild, large-bodied animals, known as 'megafauna'. This focus reflects the strong ecological impacts of large-bodied animals, their widespread loss during the last 50,000 years and their high diversity and ubiquity in the preceding 50 million years. Restoring abundant, diverse, wild-living megafauna is expected to promote vegetation heterogeneity, seed dispersal, nutrient cycling and biotic microhabitats. These are fundamental drivers of biodiversity and ecosystem function and are likely to gain importance for maintaining a biodiverse biosphere under increasingly novel ecological conditions. Non-native megafauna species may contribute to these effects as ecological surrogates of extinct species or by promoting ecological functionality within novel assemblages. Trophic rewilding has strong upscaling potential via population growth and expansion of wild fauna. It is likely to facilitate biotic adaptation to changing climatic conditions and resilience to ecosystem collapse, and to curb some negative impacts of globalization, notably the dominance of invasive alien plants. Finally, we discuss the complexities of realizing the biodiversity benefits that trophic rewilding offers under novel biosphere conditions in a heavily populated world.
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Affiliation(s)
- Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark.
| | - Robert Buitenwerf
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
| | - Elizabeth Le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark; Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, Mammal Research Institute, University of Pretoria, Pretoria 0028, South Africa
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3
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Kaštovská E, Mastný J, Konvička M. Rewilding by large ungulates contributes to organic carbon storage in soils. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 355:120430. [PMID: 38428182 DOI: 10.1016/j.jenvman.2024.120430] [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: 11/06/2023] [Revised: 02/16/2024] [Accepted: 02/17/2024] [Indexed: 03/03/2024]
Abstract
The concept of rewilding, which focuses on managing ecosystem functions through self-regulation by restoring trophic interactions through introduced animal species with little human intervention, has gained increasing attention as a proactive and efficient approach to restoring ecosystems quickly and on a large scale. However, the science of rewilding has been criticized for being largely theory-based rather than evidence-based, with available data being geographically biased towards the Netherlands and Scandinavian countries, and a lack of objective data on rewilding effects on soil processes and C sequestration. In response to a call for data-driven experimental rewilding projects focused on national contexts, we collected unique data on the effects of large herbivore rewilding on soil properties from eight sites in the Czech Republic. These include sites with a wide range of edaphic characteristics that were grazed by Exmoor ponies, European bison, and back-bred Bos primigenius cattle (singly or in combination) for 2-6 years on areas ranging from ≈30 to ≈250 ha. Despite the relatively short duration of rewilding actions and considerable variability in the response rate of soil properties to grazing, our results indicate improved nutrient availability (evidenced by higher nitrification rate or higher soluble nitrogen concentration) and accelerated ecosystem metabolism (higher soil microbial biomass and dissolved carbon content). On longer-grazed pastures, rewilding contributed to soil carbon sequestration associated with increased water holding capacity and improved soil structure. However, other soil properties (reduced dissolved P concentration or total P content) showed signs of low P availability in the soils of the rewilding sites. Therefore, carcass retention should be considered where possible. Our data, although limited in number and geographic coverage, allow us to conclude that large ungulate rewilding has the potential to enhance soil carbon sequestration and related ecosystem services in rewilding areas. At the same time, we urge similar monitoring as an essential part of other rewilding projects, which will ultimately allow much more robust conclusions about the effects of this management on soils.
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Affiliation(s)
- Eva Kaštovská
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic.
| | - Jiří Mastný
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic.
| | - Martin Konvička
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic; Biology Centre CAS, Institute of Entomology, 37005 České Budějovice, Czech Republic.
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4
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Buckley YM, Torsney A. When function, not origin, matters. Science 2024; 383:478-479. [PMID: 38301019 DOI: 10.1126/science.adn4126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Native and introduced megaherbivores similarly affect plant diversity and abundance.
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Affiliation(s)
- Yvonne M Buckley
- Co-Centre for Climate + Biodiversity and Water, School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
| | - Andrew Torsney
- School of Natural Sciences, Zoology, Trinity College Dublin, Dublin 2, Ireland
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5
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Bergman J, Pedersen RØ, Lundgren EJ, Lemoine RT, Monsarrat S, Pearce EA, Schierup MH, Svenning JC. Worldwide Late Pleistocene and Early Holocene population declines in extant megafauna are associated with Homo sapiens expansion rather than climate change. Nat Commun 2023; 14:7679. [PMID: 37996436 PMCID: PMC10667484 DOI: 10.1038/s41467-023-43426-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023] Open
Abstract
The worldwide extinction of megafauna during the Late Pleistocene and Early Holocene is evident from the fossil record, with dominant theories suggesting a climate, human or combined impact cause. Consequently, two disparate scenarios are possible for the surviving megafauna during this time period - they could have declined due to similar pressures, or increased in population size due to reductions in competition or other biotic pressures. We therefore infer population histories of 139 extant megafauna species using genomic data which reveal population declines in 91% of species throughout the Quaternary period, with larger species experiencing the strongest decreases. Declines become ubiquitous 32-76 kya across all landmasses, a pattern better explained by worldwide Homo sapiens expansion than by changes in climate. We estimate that, in consequence, total megafauna abundance, biomass, and energy turnover decreased by 92-95% over the past 50,000 years, implying major human-driven ecosystem restructuring at a global scale.
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Affiliation(s)
- Juraj Bergman
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark.
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark.
| | - Rasmus Ø Pedersen
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Erick J Lundgren
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, Australia
| | - Rhys T Lemoine
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Sophie Monsarrat
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Rewilding Europe, Toernooiveld 1, 6525 ED, Nijmegen, The Netherlands
| | - Elena A Pearce
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Mikkel H Schierup
- Bioinformatics Research Centre, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
- Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, DK-8000, Aarhus C, Denmark
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6
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Pahl CC, Ruedas LA. Big boned: How fat storage and other adaptations influenced large theropod foraging ecology. PLoS One 2023; 18:e0290459. [PMID: 37910492 PMCID: PMC10619836 DOI: 10.1371/journal.pone.0290459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 08/08/2023] [Indexed: 11/03/2023] Open
Abstract
Dinosaur foraging ecology has been the subject of scientific interest for decades, yet much of what we understand about it remains hypothetical. We wrote an agent-based model (ABM) to simulate meat energy sources present in dinosaur environments, including carcasses of giant sauropods, along with living, huntable prey. Theropod dinosaurs modeled in this environment (specifically allosauroids, and more particularly, Allosaurus Marsh, 1877) were instantiated with heritable traits favorable to either hunting success or scavenging success. If hunter phenotypes were more reproductively successful, their traits were propagated into the population through their offspring, resulting in predator specialists. If selective pressure favored scavenger phenotypes, the population would evolve to acquire most of their calories from carrion. Data generated from this model strongly suggest that theropods in sauropod-dominated systems evolved to detect carcasses, consume and store large quantities of fat, and dominate carcass sites. Broadly speaking, selective forces did not favor predatory adaptations, because sauropod carrion resource pools, as we modeled them, were too profitable for prey-based resource pools to be significant. This is the first research to test selective pressure patterns in dinosaurs, and the first to estimate theropod mass based on metabolic constraints.
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Affiliation(s)
- Cameron C. Pahl
- Department of Biology and Museum of Vertebrate Biology, Science Research and Teaching Center—246, Portland State University, Portland, Oregon, United States of America
| | - Luis A. Ruedas
- Department of Biology and Museum of Vertebrate Biology, Science Research and Teaching Center—246, Portland State University, Portland, Oregon, United States of America
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7
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Mills KL, Belant JL, Beukes M, Dröge E, Everatt KT, Fyumagwa R, Green DS, Hayward MW, Holekamp KE, Radloff FGT, Spong G, Suraci JP, Van der Weyde LK, Wilmers CC, Carter NH, Sanders NJ. Tradeoffs between resources and risks shape the responses of a large carnivore to human disturbance. Commun Biol 2023; 6:986. [PMID: 37848509 PMCID: PMC10582050 DOI: 10.1038/s42003-023-05321-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 09/04/2023] [Indexed: 10/19/2023] Open
Abstract
Wide-ranging carnivores experience tradeoffs between dynamic resource availabilities and heterogeneous risks from humans, with consequences for their ecological function and conservation outcomes. Yet, research investigating these tradeoffs across large carnivore distributions is rare. We assessed how resource availability and anthropogenic risks influence the strength of lion (Panthera leo) responses to disturbance using data from 31 sites across lions' contemporary range. Lions avoided human disturbance at over two-thirds of sites, though their responses varied depending on site-level characteristics. Lions were more likely to exploit human-dominated landscapes where resources were limited, indicating that resource limitation can outweigh anthropogenic risks and might exacerbate human-carnivore conflict. Lions also avoided human impacts by increasing their nocturnal activity more often at sites with higher production of cattle. The combined effects of expanding human impacts and environmental change threaten to simultaneously downgrade the ecological function of carnivores and intensify human-carnivore conflicts, escalating extinction risks for many species.
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Affiliation(s)
- Kirby L Mills
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA.
| | - Jerrold L Belant
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA
| | - Maya Beukes
- Senckenberg Research Institute and Nature Museum, Terrestrial Zoology, Frankfurt, Germany
| | - Egil Dröge
- WildCRU, Department of Biology, University of Oxford, Tubney, UK
- Zambian Carnivore Programme, Mfuwe, Zambia
| | - Kristoffer T Everatt
- Panthera, New York, NY, USA
- Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, South Africa
- Greater Limpopo Carnivore Programme, Limpopo, Mozambique
| | - Robert Fyumagwa
- Wildlife Conservation Initiative, Arusha, United Republic of Tanzania
| | - David S Green
- Institute for Natural Resources, Portland State University, Portland, OR, USA
| | - Matt W Hayward
- Conservation Science Research Group, School of Environmental and Life Science, University of Newcastle, Callaghan, NSW, Australia
- Centre for African Conservation Ecology, Nelson Mandela University, Qgeberha, South Africa
- Centre for Wildlife Management, University of Pretoria, Tshwane, South Africa
| | - Kay E Holekamp
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
- Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, Michigan, MI, USA
| | - F G T Radloff
- Department of Conservation and Marine Sciences, Faculty of Applied Sciences, Cape Peninsula University of Technology, Cape Town, South Africa
| | - Göran Spong
- Molecular Ecology Group, SLU, 901 83, UMEÅ, Sweden
| | | | - Leanne K Van der Weyde
- Cheetah Conservation Botswana, Gaborone, Botswana
- San Diego Zoo Institute for Conservation Research, Escondido, CA, USA
| | | | - Neil H Carter
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, USA
| | - Nathan J Sanders
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
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8
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Mungi NA, Jhala YV, Qureshi Q, le Roux E, Svenning JC. Megaherbivores provide biotic resistance against alien plant dominance. Nat Ecol Evol 2023; 7:1645-1653. [PMID: 37652995 DOI: 10.1038/s41559-023-02181-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 07/26/2023] [Indexed: 09/02/2023]
Abstract
While human-driven biological invasions are rapidly spreading, finding scalable and effective control methods poses an unresolved challenge. Here, we assess whether megaherbivores-herbivores reaching ≥1,000 kg of body mass-offer a nature-based solution to plant invasions. Invasive plants are generally adapted to maximize vegetative growth. Megaherbivores, with broad dietary tolerances, could remove large biomass of established plants, facilitating new plant growth. We used a massive dataset obtained from 26,838 camera stations and 158,979 vegetation plots to assess the relationships between megaherbivores, native plants and alien plants across India (~121,330 km2). We found a positive relationship between megaherbivore abundance and native plant richness and abundance, and a concomitant reduction in alien plant abundance. This relationship was strongest in protected areas with midproductive ecosystem and high megaherbivore density but it was lost in areas where thicket-forming alien plants predominated (>40% cover). By incorporating the role of ecosystem productivity, plants traits and densities of megaherbivores on megaherbivore-vegetation relationships, our study highlights a function of megaherbivores in controlling alien plant proliferation and facilitating diverse native plants in invaded ecosystems. The study shows great potential for megafauna-based trophic rewilding as a nature-based solution to counteract dominance of plant invasions.
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Affiliation(s)
- Ninad Avinash Mungi
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark.
- Wildlife Institute of India, Dehradun, India.
| | | | | | - Elizabeth le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) & Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
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9
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Bibi F, Cantalapiedra JL. Plio-Pleistocene African megaherbivore losses associated with community biomass restructuring. Science 2023; 380:1076-1080. [PMID: 37289876 DOI: 10.1126/science.add8366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 05/10/2023] [Indexed: 06/10/2023]
Abstract
Fossil abundance data can reveal ecological dynamics underpinning taxonomic declines. Using fossil dental metrics, we reconstructed body mass and mass-abundance distributions in Late Miocene to recent African large mammal communities. Despite collection biases, fossil and extant mass-abundance distributions are highly similar, with unimodal distributions likely reflecting savanna environments. Above 45 kilograms, abundance decreases exponentially with mass, with slopes close to -0.75, as predicted by metabolic scaling. Furthermore, communities before ~4 million years ago had considerably more large-sized individuals, with a greater proportion of total biomass allocated in larger size categories, than did later communities. Over time, individuals and biomass were redistributed into smaller size categories, reflecting a gradual loss of large-sized individuals from the fossil record paralleling the long-term decline of Plio-Pleistocene large mammal diversity.
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Affiliation(s)
- Faysal Bibi
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, 10115 Berlin, Germany
| | - Juan L Cantalapiedra
- GloCEE-Global Change Ecology and Evolution Research Group, Department of Life Sciences, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain
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10
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Hanberry BB, Faison EK. Re-framing deer herbivory as a natural disturbance regime with ecological and socioeconomic outcomes in the eastern United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161669. [PMID: 36681343 DOI: 10.1016/j.scitotenv.2023.161669] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 06/17/2023]
Abstract
Natural disturbances are critical ecosystem processes, with both ecological and socioeconomic benefits and disadvantages. Large herbivores are natural disturbances that have removed plant biomass for millions of years, although herbivore influence likely has declined during the past thousands of years corresponding with extinctions and declines in distributions and abundances of most animal species. Nonetheless, the conventional view, particularly in eastern North America, is that herbivory by large wild herbivores is at unprecedented levels, resulting in unnatural damage to forests. Here, we propose consideration of large herbivores as a natural disturbance that also imparts many crucial ecological advantages, using white-tailed deer (Odocoileus virginianus), the only wild large herbivore remaining throughout the eastern U.S., as our focal species. We examined evidence of detrimental effects of browsing on trees and forbs. We then considered that deer contribute to both fuel reduction and ecological restoration of herbaceous plants and historical open forests of savannas and woodlands by controlling tree and shrub densities, mimicking the consumer role of fire. Similarly to other disturbances, deer disturbance 'regimes' are uneven in severity across different ecosystems and landscapes, resulting in heterogeneity and diversity. In addition to biodiversity support and fuel reduction, socioeconomic benefits include >$20 billion dollars per year by 10 million hunters that support jobs and wildlife agencies, non-consumptive enjoyment of nature by 80 million people, cultural importance, and deer as ecological ambassadors, whereas costs include about $5 billion and up to 450 human deaths per year for motor vehicle accidents, along with crop damage and disease transmission. From a perspective of historical ecology rather than current baselines, deer impart a fundamental disturbance process with many ecological benefits and a range of socioeconomic effects.
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Affiliation(s)
- Brice B Hanberry
- USDA Forest Service, Rocky Mountain Research Station, Rapid City, SD 57702, United States of America.
| | - Edward K Faison
- Highstead, PO Box 1097, Redding, CT 06875, United States of America
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11
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du Toit JT. Steps to operationalize a rewilding decision: Focus on functional types. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1114856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
If transparent and inclusive stakeholder discussion delivers a consensus for active rewilding, then five steps are recommended for operationalizing that decision, focused initially on the large herbivore assemblage. Consideration of large predators could follow, contingent upon the establishment of prey populations. First, determine the potential biomass density (kg/km2) of large mammalian herbivores in the target landscape. Regression models based on rainfall or primary productivity are helpful if applicable, otherwise comparative studies are needed. Second, use empirical data from reference ecosystems to apportion biomass density among functional types, crudely defined by body size and feeding type (grazer, browser, mixed feeder). Third, identify specific functional traits (coarse grazing, endozoochory, etc.) of particular local importance. Fourth, identify species within each functional type that are already present, estimate their potential biomass densities, and thus identify the shortfall within each cell of the body size x feeding type matrix. A candidate set of native and non-native (surrogate) species is then identified to make up the shortfalls. This is followed by an iterative process of estimating equilibrium population sizes, stakeholder acceptance, and viability of each potential population. Fifth, stakeholders must be inclusively re-engaged to visualize the potential assemblage, its expected functional interactions, the ecosystem services to be delivered, and the long-term costs (including opportunity costs) and benefits. When a plan is supported, local stakeholders should be integrated as active participants in the implementation, monitoring, and championing of their rewilding project.
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12
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Pérez-Barbería FJ, Gómez JA, Gordon IJ. Legislative hurdles to using traditional domestic livestock in rewilding programmes in Europe. AMBIO 2023; 52:585-597. [PMID: 36580270 PMCID: PMC9849629 DOI: 10.1007/s13280-022-01822-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 07/12/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
Rewilding is a restoration strategy that aims to return anthropogenic ecosystems to a "self-organized" state, by reinstating trophic complexity through disturbance (e.g. predation, herbivory), dispersal and connectivity. In depopulated areas of Europe, lite versions of rewilding, that maintain but minimize the management of rewilding species (e.g. predators, large herbivores) is gaining support. Livestock rewilding (LR) is a form of rewilding-lite, that uses livestock landraces as keystone species in the restoration of herbivory (the functional integrity of ecosystems) offering ecosystem services, such as ecotourism and the sale of livestock population surpluses, that can mitigate the economic and social effects of rural depopulation. Many challenges remain to implementing LR, including (i) more empirical evidence is required of the feasibility of LR across a variety of habitats and conditions, and (ii) understanding the hurdles that legislation poses for LR, the latter being the aim of this study. To accomplish this, we reviewed the EU legislation on environmental protection, animal health and welfare, identification and traceability, and ownership and civil responsibility, to assess how this might apply to LR. Although there is no specific EU legislation prohibiting LR, the review indicates that it is not clear what legislation applies to LR, as LR's status lies between that of livestock and wild species. As such the existing legislation can be a serious impediment to the development of LR programmes. We highlight the needs for a legal definition, and status of LR species and their ownership. We propose ways to adapt this legislation to support the application of LR programmes in abandoned areas of EU, for example, by using legal exceptions intended for livestock under extensive animal farming systems.
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Affiliation(s)
- F. Javier Pérez-Barbería
- Biodiversity Research Institute (University of Oviedo Spanish Research Council Principado de Asturias), 33600 Mieres, Asturias Spain
- Department of Agroforestry Science and Technology and Genetics, Institute of Regional Development, Game and Livestock Resources Unit, University of Castilla-La Mancha, IREC, 02071 Albacete, Spain
| | - J. Angel Gómez
- Consejería Agricultura, Agua y Desarrollo Rural Castilla-La Mancha, Oficina Comarcal Agraria, C/Brunete, 21, La Roda, 02630 Albacete, Spain
| | - Iain J. Gordon
- Australian National University | ANU Fenner School of Environment & Society, Canberra, ACT Australia
- 5 Lawson Street, Mysterton, QLD 4812 Australia
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Christianen MJA, Smulders FOH, Vonk JA, Becking LE, Bouma TJ, Engel SM, James RK, Nava MI, de Smit JC, van der Zee JP, Palsbøll PJ, Bakker ES. Seagrass ecosystem multifunctionality under the rise of a flagship marine megaherbivore. GLOBAL CHANGE BIOLOGY 2023; 29:215-230. [PMID: 36330798 PMCID: PMC10099877 DOI: 10.1111/gcb.16464] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/09/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Large grazers (megaherbivores) have a profound impact on ecosystem functioning. However, how ecosystem multifunctionality is affected by changes in megaherbivore populations remains poorly understood. Understanding the total impact on ecosystem multifunctionality requires an integrative ecosystem approach, which is especially challenging to obtain in marine systems. We assessed the effects of experimentally simulated grazing intensity scenarios on ecosystem functions and multifunctionality in a tropical Caribbean seagrass ecosystem. As a model, we selected a key marine megaherbivore, the green turtle, whose ecological role is rapidly unfolding in numerous foraging areas where populations are recovering through conservation after centuries of decline, with an increase in recorded overgrazing episodes. To quantify the effects, we employed a novel integrated index of seagrass ecosystem multifunctionality based upon multiple, well-recognized measures of seagrass ecosystem functions that reflect ecosystem services. Experiments revealed that intermediate turtle grazing resulted in the highest rates of nutrient cycling and carbon storage, while sediment stabilization, decomposition rates, epifauna richness, and fish biomass are highest in the absence of turtle grazing. In contrast, intense grazing resulted in disproportionally large effects on ecosystem functions and a collapse of multifunctionality. These results imply that (i) the return of a megaherbivore can exert strong effects on coastal ecosystem functions and multifunctionality, (ii) conservation efforts that are skewed toward megaherbivores, but ignore their key drivers like predators or habitat, will likely result in overgrazing-induced loss of multifunctionality, and (iii) the multifunctionality index shows great potential as a quantitative tool to assess ecosystem performance. Considerable and rapid alterations in megaherbivore abundance (both through extinction and conservation) cause an imbalance in ecosystem functioning and substantially alter or even compromise ecosystem services that help to negate global change effects. An integrative ecosystem approach in environmental management is urgently required to protect and enhance ecosystem multifunctionality.
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Affiliation(s)
- Marjolijn J. A. Christianen
- Aquatic Ecology and Water Quality Management GroupWageningen University & ResearchWageningenThe Netherlands
- Marine Evolution and Conservation GroupGroningen Institute for Evolutionary Life Sciences, University of GroningenGroningenThe Netherlands
| | - Fee O. H. Smulders
- Aquatic Ecology and Water Quality Management GroupWageningen University & ResearchWageningenThe Netherlands
| | - Jan Arie Vonk
- Department of Freshwater and Marine EcologyInstitute for Biodiversity and Ecosystem Dynamics (IBED), University of AmsterdamAmsterdamThe Netherlands
| | - Leontine E. Becking
- Aquaculture and Fisheries groupWageningen University & Research CentreWageningenThe Netherlands
| | - Tjeerd J. Bouma
- Department of Estuarine and Delta Systems, Royal Netherlands Institute for Sea Research (NIOZ)YersekeThe Netherlands
- Department of Physical Geography, Faculty of GeosciencesUtrecht UniversityUtrechtThe Netherlands
| | - Sabine M. Engel
- STINAPA, Bonaire National Parks FoundationBonaireCaribbean Netherlands
| | - Rebecca K. James
- Department of Estuarine and Delta Systems, Royal Netherlands Institute for Sea Research (NIOZ)YersekeThe Netherlands
- Biogeochemistry and Modeling of the Earth System GroupUniversité libre de BruxellesBruxellesBelgium
| | - Mabel I. Nava
- Sea Turtle Conservation BonaireBonaireCaribbean Netherlands
| | - Jaco C. de Smit
- Department of Estuarine and Delta Systems, Royal Netherlands Institute for Sea Research (NIOZ)YersekeThe Netherlands
- Department of Physical Geography, Faculty of GeosciencesUtrecht UniversityUtrechtThe Netherlands
| | - Jurjan P. van der Zee
- Marine Evolution and Conservation GroupGroningen Institute for Evolutionary Life Sciences, University of GroningenGroningenThe Netherlands
| | - Per J. Palsbøll
- Marine Evolution and Conservation GroupGroningen Institute for Evolutionary Life Sciences, University of GroningenGroningenThe Netherlands
- Center for Coastal StudiesProvincetownMassachusettsUSA
| | - Elisabeth S. Bakker
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
- Wildlife Ecology and Conservation Group, Wageningen University & ResearchWageningenThe Netherlands
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Gulick AG, Johnson RA, Palma LA, Kusel AM, Pollock CG, Hillis‐Starr Z, Bolten AB, Bjorndal KA. An underwater Serengeti: Seagrass‐mediated effects on intake and cultivation grazing behavior of a marine megaherbivore. Ecosphere 2022. [DOI: 10.1002/ecs2.4259] [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)
- Alexandra G. Gulick
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
| | - Robert A. Johnson
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
| | - Laura A. Palma
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
| | - Ashley M. Kusel
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
| | - Clayton G. Pollock
- Division of Resource Management and Research, Buck Island Reef National Monument National Park Service Christiansted St. Croix US Virgin Islands
| | - Zandy Hillis‐Starr
- Division of Resource Management and Research, Buck Island Reef National Monument National Park Service Christiansted St. Croix US Virgin Islands
| | - Alan B. Bolten
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
| | - Karen A. Bjorndal
- Archie Carr Center for Sea Turtle Research and Department of Biology University of Florida Gainesville Florida USA
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