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Lundgren EJ, Bergman J, Trepel J, le Roux E, Monsarrat S, Kristensen JA, Pedersen RØ, Pereyra P, Tietje M, Svenning JC. Functional traits-not nativeness-shape the effects of large mammalian herbivores on plant communities. Science 2024; 383:531-537. [PMID: 38301018 DOI: 10.1126/science.adh2616] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 11/30/2023] [Indexed: 02/03/2024]
Abstract
Large mammalian herbivores (megafauna) have experienced extinctions and declines since prehistory. Introduced megafauna have partly counteracted these losses yet are thought to have unusually negative effects on plants compared with native megafauna. Using a meta-analysis of 3995 plot-scale plant abundance and diversity responses from 221 studies, we found no evidence that megafauna impacts were shaped by nativeness, "invasiveness," "feralness," coevolutionary history, or functional and phylogenetic novelty. Nor was there evidence that introduced megafauna facilitate introduced plants more than native megafauna. Instead, we found strong evidence that functional traits shaped megafauna impacts, with larger-bodied and bulk-feeding megafauna promoting plant diversity. Our work suggests that trait-based ecology provides better insight into interactions between megafauna and plants than do concepts of nativeness.
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Affiliation(s)
- Erick J Lundgren
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane City, Queensland, Australia
| | - Juraj Bergman
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Jonas Trepel
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
- Department of Conservation Biology, University of Göttingen, Göttingen, Germany
| | - Elizabeth le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
- Mammal Research Institute, University of Pretoria, Hatfield, South Africa
- Aarhus Institute for Advanced Studies, Aarhus University, Aarhus, Denmark
| | - Sophie Monsarrat
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
- Rewilding Europe, Nijmegen, Netherlands
| | - Jeppe Aagaard Kristensen
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
- Leverhulme Centre for Nature Recovery, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Rasmus Østergaard Pedersen
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Patricio Pereyra
- Consejo Nacional de Investigaciones, Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
- Centro de Investigación Aplicada y Transferencia, Tecnológica en Recursos Marinos Almirante Storni (CIMAS), San Antonio Oeste, Argentina
| | - Melanie Tietje
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Aarhus, Denmark
- Section for Ecoinformatics and Biodiversity, Department of Biology, Aarhus University, Aarhus, Denmark
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Whyte PJ, Henderson DC, Heuer K, Ford AT. Bison and bighorns: Assessing the potential impacts of reintroducing a large herbivore to a mountainous landscape. Ecol Evol 2024; 14:e11008. [PMID: 38414569 PMCID: PMC10897061 DOI: 10.1002/ece3.11008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 01/09/2024] [Accepted: 01/27/2024] [Indexed: 02/29/2024] Open
Abstract
The reintroduction of wildlife can have significant ecological impacts by altering the flow of energy in food webs. Recently, plains bison were reintroduced to part of Banff National Park after a 150-year absence. The large herbivore's reintroduction was expected to have far-reaching effects on the ecosystem due to its significant energy requirements and interactions with habitat and other sympatric species. This study explores the impacts of bison reintroduction on the movement and resource use of another large-bodied grazer, the Rocky Mountain bighorn sheep. Between 2018 and 2021, we collected data from GPS collars fit on 39 bighorn sheep and 11 bison. We analyzed home range patterns, resource selection, and interactions to investigate the potential for interspecific competition, facilitation, and resource complementarity. At the population level, bison and bighorn sheep exhibited low levels of spatial overlap and there was strong evidence of resource separation in all seasons. Interactions between species did not appear to affect sheep movement rates; however, we did see differences in forage selection patterns for sheep with overlapping home ranges with bison. Collectively, results did not support the potential for competition or facilitation between bison and bighorn sheep and instead provided the strongest evidence of complementarity.
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Affiliation(s)
- Peter J. Whyte
- Department of BiologyUniversity of British Columbia—OkanaganKelownaBritish ColumbiaCanada
- Parks CanadaBanff National ParkBanffAlbertaCanada
| | - Darcy C. Henderson
- Canadian Wildlife ServiceEnvironment & Climate Change CanadaKelownaBritish ColumbiaCanada
| | | | - Adam T. Ford
- Department of BiologyUniversity of British Columbia—OkanaganKelownaBritish ColumbiaCanada
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3
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Furey GN, Tilman D. Trade-offs between deer herbivory and nitrogen competition alter grassland forb composition. Oecologia 2024; 204:47-58. [PMID: 38091102 PMCID: PMC10830730 DOI: 10.1007/s00442-023-05485-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 11/14/2023] [Indexed: 12/23/2023]
Abstract
Two of the major factors that control the composition of herbaceous plant communities are competition for limiting soil resources and herbivory. We present results from a 14-year full factorial experiment in a tallgrass prairie ecosystem that crossed nitrogen (N) addition with fencing to exclude white-tailed deer, Odocoileus virginianus, from half the plots. Deer presence was associated with only modest decreases in aboveground plant biomass (14% decrease; -45 ± 19 g m-2) with no interaction with N addition. N addition at 5.44 and 9.52 g N m-2 year-1 led to increases in biomass. There were weak increases in species richness associated with deer presence, but only for no or low added N (1 and 2 g N m-2 year-1). However, the presence of deer greatly impacted the abundances of some of the dominant perennial forb species, but not the dominant grasses. Deer presence increased the abundance of the forb Artemisia ludoviciana by 34 ± 12 SE g m-2 (94%) and decreased the forb Solidago rigida by 32 ± 13 SE g m-2 (79%). We suggest that these changes may have resulted from trade-offs in plant competitive ability for soil N versus resistance to deer herbivory. Field observations suggest deer acted as florivores, mainly consuming the flowers of susceptible forb species. The preferential consumption of flowers of forbs that seem to be superior N competitors appears to create an axis of interspecific niche differentiation. The overpopulation of white-tailed deer in many tallgrass reserves likely structures the abundance of forb species.
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Affiliation(s)
- George N Furey
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Universitetstunet 3, 1433, Ås, Norway.
- Department of Ecology, Evolution and Behavior, College of Biological Sciences, University of Minnesota, St. Paul, MN, USA.
| | - David Tilman
- Department of Ecology, Evolution and Behavior, College of Biological Sciences, University of Minnesota, St. Paul, MN, USA
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA
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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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5
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Pringle RM, Abraham JO, Anderson TM, Coverdale TC, Davies AB, Dutton CL, Gaylard A, Goheen JR, Holdo RM, Hutchinson MC, Kimuyu DM, Long RA, Subalusky AL, Veldhuis MP. Impacts of large herbivores on terrestrial ecosystems. Curr Biol 2023; 33:R584-R610. [PMID: 37279691 DOI: 10.1016/j.cub.2023.04.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Large herbivores play unique ecological roles and are disproportionately imperiled by human activity. As many wild populations dwindle towards extinction, and as interest grows in restoring lost biodiversity, research on large herbivores and their ecological impacts has intensified. Yet, results are often conflicting or contingent on local conditions, and new findings have challenged conventional wisdom, making it hard to discern general principles. Here, we review what is known about the ecosystem impacts of large herbivores globally, identify key uncertainties, and suggest priorities to guide research. Many findings are generalizable across ecosystems: large herbivores consistently exert top-down control of plant demography, species composition, and biomass, thereby suppressing fires and the abundance of smaller animals. Other general patterns do not have clearly defined impacts: large herbivores respond to predation risk but the strength of trophic cascades is variable; large herbivores move vast quantities of seeds and nutrients but with poorly understood effects on vegetation and biogeochemistry. Questions of the greatest relevance for conservation and management are among the least certain, including effects on carbon storage and other ecosystem functions and the ability to predict outcomes of extinctions and reintroductions. A unifying theme is the role of body size in regulating ecological impact. Small herbivores cannot fully substitute for large ones, and large-herbivore species are not functionally redundant - losing any, especially the largest, will alter net impact, helping to explain why livestock are poor surrogates for wild species. We advocate leveraging a broad spectrum of techniques to mechanistically explain how large-herbivore traits and environmental context interactively govern the ecological impacts of these animals.
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Affiliation(s)
- Robert M Pringle
- Department of Ecology & Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
| | - Joel O Abraham
- Department of Ecology & Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - T Michael Anderson
- Department of Biology, Wake Forest University, Winston Salem, NC 27109, USA
| | - Tyler C Coverdale
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Andrew B Davies
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | | | | | - Jacob R Goheen
- Department of Zoology & Physiology, University of Wyoming, Laramie, WY 82072, USA
| | - Ricardo M Holdo
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - Matthew C Hutchinson
- Department of Life & Environmental Sciences, University of California Merced, Merced, CA 95343, USA
| | - Duncan M Kimuyu
- Department of Natural Resources, Karatina University, Karatina, Kenya
| | - Ryan A Long
- Department of Fish and Wildlife Sciences, University of Idaho, Moscow, ID 83844, USA
| | - Amanda L Subalusky
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Michiel P Veldhuis
- Institute of Environmental Sciences, Leiden University, 2333 CC Leiden, The Netherlands
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Acevedo C, Barfield JP. Review: Reproductive physiology of bison and application of assisted reproductive technologies to their conservation. Animal 2023; 17 Suppl 1:100842. [PMID: 37567664 DOI: 10.1016/j.animal.2023.100842] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/22/2023] [Accepted: 04/25/2023] [Indexed: 08/13/2023] Open
Abstract
Bison are an ecologically and culturally important species on the European and North American continents. Their near extirpation was met with conservation efforts that prevented their extinction but left few animals or highly fragmented populations. Contemporary conservation efforts are focused on building ecologically and genetically sustainable bison herds for long-term conservation of the species. Assisted reproductive technologies (ARTs) can play a key role in building these herds by facilitating the movement of genetics in the form of gametes and embryos, while protecting animal well-being and ensuring biosecurity of existing bison herds. In addition, ARTs such as gamete and embryo cryopreservation can be used to protect against future losses of genetic diversity through biobanking. In this review, a brief summary of basic bison reproductive physiology is presented followed by an overview of the current state of ART in Bison bison (American bison) and Bison bonasus (European bison or wisent). Research on ART ranging from artificial insemination to in vitro embryo transfer and cloning is discussed with particular regard to the application of ART for conservation purposes. While significant progress has been made in ART for bison, there are still many opportunities to improve these technologies and expand their impact for bison conservation.
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Affiliation(s)
- Carolina Acevedo
- Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, CO 80521, USA
| | - Jennifer P Barfield
- Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, CO 80521, USA.
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Roy S, Naidu DGT, Bagchi S. Functional substitutability of native herbivores by livestock for soil carbon stock is mediated by microbial decomposers. GLOBAL CHANGE BIOLOGY 2023; 29:2141-2155. [PMID: 36732877 DOI: 10.1111/gcb.16600] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 05/28/2023]
Abstract
Grazing by large mammalian herbivores impacts climate as it can favor the size and stability of a large carbon (C) pool in the soils of grazing ecosystems. As native herbivores in the world's grasslands, steppes, and savannas are progressively being displaced by livestock, it is important to ask whether livestock can emulate the functional roles of their native counterparts. While livestock and native herbivores can have remarkable similarity in their traits, they can differ greatly in their impacts on vegetation composition which can affect soil-C. It is uncertain how these similarities and differences impact soil-C via their influence on microbial decomposers. We test competing alternative hypotheses with a replicated, long-term, landscape-level, grazing-exclusion experiment to ask whether livestock in the Trans-Himalayan ecosystem of northern India can match decadal-scale (2005-2016) soil-C stocks under native herbivores. We evaluate multiple lines of evidence from 17 variables that influence soil-C (quantity and quality of C-input from plants, microbial biomass and metabolism, microbial community composition, eDNA, veterinary antibiotics in soil), and assess their inter-relationships. Livestock and native herbivores differed in their effects on several soil microbial processes. Microbial carbon use efficiency (CUE) was 19% lower in soils under livestock. Compared to native herbivores, areas used by livestock contained 1.5 kg C m-2 less soil-C. Structural equation models showed that alongside the effects arising from plants, livestock alter soil microbial communities which is detrimental for CUE, and ultimately also for soil-C. Supporting evidence pointed toward a link between veterinary antibiotics used on livestock, microbial communities, and soil-C. Overcoming the challenges of sequestering antibiotics to minimize their potential impacts on climate, alongside microbial rewilding under livestock, may reconcile the conflicting demands from food-security and ecosystem services. Conservation of native herbivores and alternative management of livestock is crucial for soil-C stewardship to envision and achieve natural climate solutions.
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Affiliation(s)
- Shamik Roy
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India
| | - Dilip G T Naidu
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India
- Divecha Centre for Climate Change, Indian Institute of Science, Bangalore, India
| | - Sumanta Bagchi
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India
- Divecha Centre for Climate Change, Indian Institute of Science, Bangalore, India
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8
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Bison outperform cattle at restoring their home on the range. Proc Natl Acad Sci U S A 2022; 119:e2213632119. [PMID: 36170245 PMCID: PMC9546598 DOI: 10.1073/pnas.2213632119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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9
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How to help a prairie: bring on the hungry bison. Nature 2022. [PMID: 36045171 DOI: 10.1038/d41586-022-02332-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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