1
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Bravo C, Sarasa M, Bretagnolle V, Pays O. Hedgerows interact with forests to shape the abundance of mesopredators and their predation rate on eggs in farmland landscapes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 901:165712. [PMID: 37517728 DOI: 10.1016/j.scitotenv.2023.165712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 08/01/2023]
Abstract
Nest predation is the main cause of reproductive failure, particularly in ground-nesting birds on farmlands. Understanding the links between nest predation and habitat change can help design effective management schemes to constrain the negative impact of predation pressure on birds. However, the mechanisms underlying the relationships between landscape attributes, predator distribution, and nest predation are still unclear. Here, we use an experimental approach to examine the effects of distance to the hedgerow as well as hedgerow and forest densities on the abundance of major mesopredators of ground nests of our study area (i.e., corvids) and on the predation rate of artificial ground nests (n = 2576). We found evidence that landscape configuration influenced predation patterns differently depending on the predator species. Nest predation by corvids was more likely in homogeneous and open agricultural landscapes with a low density of forest and hedgerows, whereas predation by other predators was more likely close to hedgerows. Nest predation by corvids and the abundance of corvids also tended to be lower in landscapes dominated by grasslands. Other variables such as road density and distance to human settlements had contrasted effects on the likelihood of a nest being depredated by corvids, i.e., no effect with proximity to human settlements and decreasing trend with road density. Altogether, our results suggest that landscape features interact with mesopredator distribution and their predation rates of ground nests. Therefore, from a conservation and management perspective, a heterogeneous agricultural landscape that includes a mixture of crops associated with patches of forests, hedgerows, and grasslands offering alternative food to generalist predators should contribute to reducing ground-nesting bird predation.
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Affiliation(s)
- Carolina Bravo
- Centre d'Etudes Biologiques de Chizé, UMR 7372, CNRS and La Rochelle Université, F-79360 Beauvoir-sur-, Niort, France; Univ Angers, BIODIVAG, 49000 Angers, France.
| | - Mathieu Sarasa
- BEOPS, 1 Esplanade Compans Caffarelli, 31000, Toulouse, France; Fédération Nationale des Chasseurs, 92136 Issy-les-Moulineaux cedex, France
| | - Vincent Bretagnolle
- Centre d'Etudes Biologiques de Chizé, UMR 7372, CNRS and La Rochelle Université, F-79360 Beauvoir-sur-, Niort, France; LTSER «Zone Atelier Plaine & Val de Sèvre», CNRS, 79360, Villiers-en-Bois, France
| | - Olivier Pays
- Univ Angers, BIODIVAG, 49000 Angers, France; REHABS International Research Laboratory, CNRS-Université Lyon 1-Nelson Mandela University, George Campus, Madiba drive, 6531 George, South Africa
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2
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Hancock GRA, Grayshon L, Burrell R, Cuthill I, Hoodless A, Troscianko J. Habitat geometry rather than visual acuity limits the visibility of a ground-nesting bird's clutch to terrestrial predators. Ecol Evol 2023; 13:e10471. [PMID: 37720061 PMCID: PMC10501817 DOI: 10.1002/ece3.10471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 08/10/2023] [Accepted: 08/18/2023] [Indexed: 09/19/2023] Open
Abstract
The nests of ground-nesting birds rely heavily on camouflage for their survival, and predation risk, often linked to ecological changes from human activity, is a major source of mortality. Numerous ground-nesting bird populations are in decline, so understanding the effects of camouflage on their nesting behavior is relevant to their conservation concerns. Habitat three-dimensional (3D) geometry, together with predator visual abilities, viewing distance, and viewing angle, determine whether a nest is either visible, occluded, or too far away to detect. While this link is intuitive, few studies have investigated how fine-scale geometry is likely to help defend nests from different predator guilds. We quantified nest visibility based on 3D occlusion, camouflage, and predator visual modeling in northern lapwings, Vanellus vanellus, on different land management regimes. Lapwings selected local backgrounds that had a higher 3D complexity at a spatial scale greater than their entire clutches compared to local control sites. Importantly, our findings show that habitat geometry-rather than predator visual acuity-restricts nest visibility for terrestrial predators and that their field habitats, perceived by humans as open, are functionally closed with respect to a terrestrial predator searching for nests on the ground. Taken together with lapwings' careful nest site selection, our findings highlight the importance of considering habitat geometry for understanding the evolutionary ecology and management of conservation sites for ground-nesting birds.
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Affiliation(s)
| | | | - Ryan Burrell
- Faculty of Science and TechnologyBournemouth UniversityDorsetUK
| | - Innes Cuthill
- School of Biological SciencesUniversity of BristolBristolUK
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3
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Mason LR, Green RE, Hirons GJ, Skinner AM, Peault SC, Upcott EV, Wells E, Wilding DJ, Smart J. Experimental diversionary feeding of red kites Milvus milvus reduces chick predation and enhances breeding productivity of northern lapwings Vanellus vanellus. J Nat Conserv 2021. [DOI: 10.1016/j.jnc.2021.126051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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4
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Jellesmark S, Ausden M, Blackburn TM, Gregory RD, Hoffmann M, Massimino D, McRae L, Visconti P. A counterfactual approach to measure the impact of wet grassland conservation on U.K. breeding bird populations. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2021; 35:1575-1585. [PMID: 33415751 DOI: 10.1111/cobi.13692] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
Wet grassland populations of wading birds in the United Kingdom have declined severely since 1990. To help mitigate these declines, the Royal Society for the Protection of Birds has restored and managed lowland wet grassland nature reserves to benefit these and other species. However, the impact of these reserves on bird population trends has not been evaluated experimentally due to a lack of control populations. We compared population trends from 1994 to 2018 among 5 bird species of conservation concern that breed on these nature reserves with counterfactual trends created from matched breeding bird survey observations. We compared reserve trends with 3 different counterfactuals based on different scenarios of how reserve populations could have developed in the absence of conservation. Effects of conservation interventions were positive for all 4 targeted wading bird species: Lapwing (Vanellus vanellus), Redshank (Tringa totanus), Curlew (Numenius arquata), and Snipe (Gallinago gallinago). There was no positive effect of conservation interventions on reserves for the passerine, Yellow Wagtail (Motacilla flava). Our approach using monitoring data to produce valid counterfactual controls is a broadly applicable method allowing large-scale evaluation of conservation impact.
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Affiliation(s)
- Sean Jellesmark
- Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, Gower Street, London, WC1E 6BT, U.K
- Institute of Zoology, Zoological Society of London, London, U.K
| | - Malcolm Ausden
- RSPB Centre for Conservation Science, The Lodge, Sandy, Bedfordshire, SG19 2DL, U.K
| | - Tim M Blackburn
- Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, Gower Street, London, WC1E 6BT, U.K
- Institute of Zoology, Zoological Society of London, London, U.K
| | - Richard D Gregory
- Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, Gower Street, London, WC1E 6BT, U.K
- RSPB Centre for Conservation Science, The Lodge, Sandy, Bedfordshire, SG19 2DL, U.K
| | - Mike Hoffmann
- Institute of Zoology, Zoological Society of London, London, U.K
| | - Dario Massimino
- British Trust for Ornithology, The Nunnery, Thetford, IP24 2PU, U.K
| | - Louise McRae
- Institute of Zoology, Zoological Society of London, London, U.K
| | - Piero Visconti
- International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, Laxenburg, A-2361, Austria
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5
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Khorozyan I. Dealing with false positive risk as an indicator of misperceived effectiveness of conservation interventions. PLoS One 2021; 16:e0255784. [PMID: 34352882 PMCID: PMC8342041 DOI: 10.1371/journal.pone.0255784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 07/23/2021] [Indexed: 11/18/2022] Open
Abstract
As human pressures on the environment continue to spread and intensify, effective conservation interventions are direly needed to prevent threats, reduce conflicts, and recover populations and landscapes in a liaison between science and conservation. It is practically important to discriminate between true and false (or misperceived) effectiveness of interventions as false perceptions may shape a wrong conservation agenda and lead to inappropriate decisions and management actions. This study used the false positive risk (FPR) to estimate the rates of misperceived effectiveness of electric fences (overstated if reported as effective but actually ineffective based on FPR; understated otherwise), explain their causes and propose recommendations on how to improve the representation of true effectiveness. Electric fences are widely applied to reduce damage to fenced assets, such as livestock and beehives, or increase survival of fenced populations. The analysis of 109 cases from 50 publications has shown that the effectiveness of electric fences was overstated in at least one-third of cases, from 31.8% at FPR = 0.2 (20% risk) to 51.1% at FPR = 0.05 (5% risk, true effectiveness). In contrast, understatement reduced from 23.8% to 9.5% at these thresholds of FPR. This means that truly effective applications of electric fences were only 48.9% of all cases reported as effective, but truly ineffective cases were 90.5%, implying that the effectiveness of electric fences was heavily overstated. The main reasons of this bias were the lack of statistical testing or improper reporting of test results (63.3% of cases) and interpretation of marginally significant results (p < 0.05, p < 0.1 and p around 0.05) as indicators of effectiveness (10.1%). In conclusion, FPR is an important tool for estimating true effectiveness of conservation interventions and its application is highly recommended to disentangle true and false effectiveness for planning appropriate conservation actions. Researchers are encouraged to calculate FPR, publish its constituent statistics (especially treatment and control sample sizes) and explicitly provide test results with p values. It is suggested to call the effectiveness “true” if FPR < 0.05, “suggestive” if 0.05 ≤ FPR < 0.2 and “false” if FPR ≥ 0.2.
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Affiliation(s)
- Igor Khorozyan
- Department of Conservation Biology, Georg-August-Universität, Göttingen, Germany
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6
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Habitats supporting wader communities in Europe and relations between agricultural land use and breeding densities: A review. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2021.e01657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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7
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Christensen DL, Harmon KC, Wehr NH, Price MR. Mammal-exclusion fencing improves the nesting success of an endangered native Hawaiian waterbird. PeerJ 2021; 9:e10722. [PMID: 33717665 PMCID: PMC7931714 DOI: 10.7717/peerj.10722] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/16/2020] [Indexed: 11/30/2022] Open
Abstract
Invasive predator control is often critical to improving the nesting success of endangered birds, but methods of control vary in cost and effectiveness. Poison-baiting or trapping and removal are relatively low-cost, but may have secondary impacts on non-target species, and may not completely exclude mammals from nesting areas. Mammal-exclusion fencing has a substantial up-front cost, but due to cost savings over the lifetime of the structure and the complete exclusion of mammalian predators, this option is increasingly being utilized to protect threatened species such as ground-nesting seabirds. However, non-mammalian predators are not excluded by these fences and may continue to impact nesting success, particularly in cases where the fence is designed for the protection of waterbirds, open to an estuary or wetland on one side. Thus, there remains a research gap regarding the potential gains in waterbird nesting success from the implementation of mammal-exclusion fencing in estuarine systems. In this study, we compared the nesting success of endangered Hawaiian Stilts (Ae‘o; Himantopus mexicanus knudseni) within a mammal-exclusion fence to that of breeding pairs in a nearby wetland where trapping was the sole means for removing invasive mammals. We predicted success would be greater for breeding pairs inside the exclusion fence and the hatchlings inside the enclosure would spend more time in the nesting area than hatchlings at the unfenced site. During a single breeding season following construction of a mammal-exclusion fence, we used motion-activated game cameras to monitor nests at two sites, one site with mammal-exclusion fencing and one site without. Clutch sizes and hatch rates were significantly greater at the fenced site than the unfenced site, but time spent by chicks in the nesting area did not differ between sites. These results add to the mounting body of evidence that demonstrates the effectiveness of mammal-exclusion fencing in protecting endangered birds and suggests it can aid endangered Hawaiian waterbirds toward recovery. These results also suggest that the single greatest predatory threat to the Hawaiian Stilt may be invasive mammals, despite a host of known non-mammalian predators including birds, crabs, turtles, and bullfrogs, as the complete exclusion of mammals resulted in significant gains in nesting success. As additional fences are built, future studies are necessary to compare nesting success among multiple sites and across multiple seasons to determine potential gains in fledging success and recruitment.
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Affiliation(s)
- Dain L Christensen
- Department of Natural Resources and Environmental Management, College of Tropical Agriculture and Human Resources, University of Hawaii at Mānoa, Honolulu, Hawaii, United States of America
| | - Kristen C Harmon
- Department of Natural Resources and Environmental Management, College of Tropical Agriculture and Human Resources, University of Hawaii at Mānoa, Honolulu, Hawaii, United States of America
| | - Nathaniel H Wehr
- Department of Natural Resources and Environmental Management, College of Tropical Agriculture and Human Resources, University of Hawaii at Mānoa, Honolulu, Hawaii, United States of America
| | - Melissa R Price
- Department of Natural Resources and Environmental Management, College of Tropical Agriculture and Human Resources, University of Hawaii at Mānoa, Honolulu, Hawaii, United States of America
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8
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Binny RN, Innes J, Fitzgerald N, Pech R, James A, Price R, Gillies C, Byrom AE. Long‐term biodiversity trajectories for pest‐managed ecological restorations: eradication vs. suppression. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1439] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rachelle N. Binny
- Manaaki Whenua‐Landcare Research Lincoln New Zealand
- Te Pūnaha Matatini New Zealand
| | - John Innes
- Manaaki Whenua‐Landcare Research Hamilton New Zealand
| | | | - Roger Pech
- Manaaki Whenua‐Landcare Research Lincoln New Zealand
| | - Alex James
- Te Pūnaha Matatini New Zealand
- School of Mathematics and Statistics University of Canterbury Christchurch New Zealand
| | - Robbie Price
- Manaaki Whenua‐Landcare Research Hamilton New Zealand
| | - Craig Gillies
- Department of Conservation, Biodiversity Group Hamilton New Zealand
| | - Andrea E. Byrom
- Manaaki Whenua‐Landcare Research Lincoln New Zealand
- NZ Biological Heritage National Science Challenge New Zealand
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9
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Smith D, King R, Allen BL. Impacts of exclusion fencing on target and non-target fauna: a global review. Biol Rev Camb Philos Soc 2020; 95:1590-1606. [PMID: 32725786 DOI: 10.1111/brv.12631] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 12/21/2022]
Abstract
Exclusion fencing is a common tool used to mitigate a variety of unwanted economic losses caused by problematic wildlife. While the potential for agricultural, ecological and economic benefits of pest animal exclusion are often apparent, what is less clear are the costs and benefits to sympatric non-target wildlife. This review examines the use of exclusion fencing in a variety of situations around the world to elucidate the potential outcomes of such fencing for wildlife and apply this knowledge to the recent uptake of exclusion fencing on livestock properties in the Australian rangelands. In Australia, exclusion fences are used to eliminate dingo (Canis familiaris dingo) predation on livestock, prevent crop-raiding by emus (Dromaius novaehollandiae), and enable greater control over total grazing pressure through the reduction of macropods (Macropodidae) and feral goats (Capra hircus). A total of 208 journal articles were examined for location, a broad grouping of fence type, and the reported effects the fence was having on the study species. We found 51% of the literature solely discusses intended fencing effects, 42% discusses unintended effects, and only 7% considers both. Africa has the highest proportion of unintended effects literature (52.0%) and Australia has the largest proportion of literature on intended effects (34.2%). We highlight the potential for exclusion fencing to have positive effects on some species and negative effects on others (such as predator exclusion fencing posing a barrier to migration of other species), which remain largely unaddressed in current exclusion fencing systems. From this review we were able to identify where and how mitigation strategies have been successfully used in the past. Harnessing the potential benefits of exclusion fencing while avoiding the otherwise likely costs to both target and non-target species will require more careful consideration than this issue has previously been afforded.
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Affiliation(s)
- Deane Smith
- University of Southern Queensland, Institute for Life Sciences and the Environment, Toowoomba, Queensland, 4350, Australia
| | - Rachel King
- University of Southern Queensland, School of Sciences, Toowoomba, Queensland, 4350, Australia
| | - Benjamin L Allen
- University of Southern Queensland, Institute for Life Sciences and the Environment, Toowoomba, Queensland, 4350, Australia.,Centre for African Conservation Ecology, Nelson Mandela University, Port Elizabeth, 6034, South Africa
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10
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Ringma J, Barnes MD, Bode M. Australian birds could benefit from predator exclusion fencing. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Affiliation(s)
- Jeremy Ringma
- School of Global, Urban and Social StudiesRMIT University Melbourne Victoria Australia
| | - Megan D. Barnes
- School of Biological SciencesThe University of Queensland Brisbane Queensland Australia
| | - Michael Bode
- Science and Engineering Faculty, Mathematical Sciences, Applied and Computational MathematicsQueensland University of Technology Brisbane Queensland Australia
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11
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Plard F, Bruns HA, Cimiotti DV, Helmecke A, Hötker H, Jeromin H, Roodbergen M, Schekkerman H, Teunissen W, Jeugd H, Schaub M. Low productivity and unsuitable management drive the decline of central European lapwing populations. Anim Conserv 2019. [DOI: 10.1111/acv.12540] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Plard
- Swiss Ornithological Institute Sempach Switzerland
| | - H. A. Bruns
- Michael‐Otto Institut im NABU Bergenhusen Germany
| | | | - A. Helmecke
- Michael‐Otto Institut im NABU Bergenhusen Germany
| | - H. Hötker
- Michael‐Otto Institut im NABU Bergenhusen Germany
| | - H. Jeromin
- Michael‐Otto Institut im NABU Bergenhusen Germany
| | - M. Roodbergen
- SOVON Vogelonderzoek Nederland Nijmegen The Netherlands
| | | | - W. Teunissen
- SOVON Vogelonderzoek Nederland Nijmegen The Netherlands
| | - H. Jeugd
- Netherlands Institute of Ecology – Dutch Centre for Avian Migration and Demography Wageningen The Netherlands
| | - M. Schaub
- Swiss Ornithological Institute Sempach Switzerland
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12
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Franks SE, Roodbergen M, Teunissen W, Carrington Cotton A, Pearce‐Higgins JW. Evaluating the effectiveness of conservation measures for European grassland-breeding waders. Ecol Evol 2018; 8:10555-10568. [PMID: 30464827 PMCID: PMC6238142 DOI: 10.1002/ece3.4532] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/27/2018] [Accepted: 08/19/2018] [Indexed: 11/16/2022] Open
Abstract
Farmland birds are among the most threatened bird species in Europe, largely as a result of agricultural intensification which has driven widespread biodiversity losses. Breeding waders associated with grassland and arable habitats are particularly vulnerable and a frequent focus of agri-environment schemes (AES) designed to halt and reverse population declines. We review existing literature, providing a quantitative assessment of the effectiveness of policy and management interventions used throughout Europe to improve population and demographic metrics of grassland-breeding waders. Targeted AES and site protection measures were more likely to be effective than less targeted AES and were ten times more likely to be effective than would be expected by chance, particularly for population trend and productivity metrics. Positive effects of AES and site protection did not appear synergistic. Management interventions which had the greatest chance of increasing population growth or productivity included modification of mowing regimes, increasing wet conditions, and the use of nest protection. Success rates varied according to the species and metric being evaluated. None of the policy or management interventions we evaluated were associated with a significant risk of negative impacts on breeding waders. Our findings support the use of agri-environment schemes, site protection, and management measures for grassland-breeding wader conservation in Europe. Due to publication bias, our findings are most applicable to intensively managed agricultural landscapes. More studies are needed to identify measures that increase chick survival. Despite broadly effective conservation measures already in use, grassland-breeding waders in Europe continue to decline. More research is needed to improve the likelihood and magnitude of positive outcomes, coupled with wider implementation of effective measures to substantially increase favorable land management for these species.
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Affiliation(s)
| | - Maja Roodbergen
- Sovon Dutch Centre for Field OrnithologyNijmegenThe Netherlands
| | - Wolf Teunissen
- Sovon Dutch Centre for Field OrnithologyNijmegenThe Netherlands
| | | | - James W. Pearce‐Higgins
- British Trust for OrnithologyThetfordUK
- Conservation Science Group, Department of ZoologyUniversity of CambridgeCambridgeUK
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13
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Roos S, Smart J, Gibbons DW, Wilson JD. A review of predation as a limiting factor for bird populations in mesopredator-rich landscapes: a case study of the UK. Biol Rev Camb Philos Soc 2018; 93:1915-1937. [PMID: 29790246 DOI: 10.1111/brv.12426] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 04/19/2018] [Accepted: 04/25/2018] [Indexed: 11/26/2022]
Abstract
The impact of increasing vertebrate predator numbers on bird populations is widely debated among the general public, game managers and conservationists across Europe. However, there are few systematic reviews of whether predation limits the population sizes of European bird species. Views on the impacts of predation are particularly polarised in the UK, probably because the UK has a globally exceptional culture of intensive, high-yield gamebird management where predator removal is the norm. In addition, most apex predators have been exterminated or much depleted in numbers, contributing to a widely held perception that the UK has high numbers of mesopredators. This has resulted in many high-quality studies of mesopredator impacts over several decades. Here we present results from a systematic review of predator trends and abundance, and assess whether predation limits the population sizes of 90 bird species in the UK. Our results confirm that the generalist predators Red Fox (Vulpes vulpes) and Crows (Corvus corone and C. cornix) occur at high densities in the UK compared with other European countries. In addition, some avian and mammalian predators have increased numerically in the UK during recent decades. Despite these high and increasing densities of predators, we found little evidence that predation limits populations of pigeons, woodpeckers and passerines, whereas evidence suggests that ground-nesting seabirds, waders and gamebirds can be limited by predation. Using life-history characteristics of prey species, we found that mainly long-lived species with high adult survival and late onset of breeding were limited by predation. Single-brooded species were also more likely to be limited by predation than multi-brooded species. Predators that depredate prey species during all life stages (i.e. from nest to adult stages) limited prey numbers more than predators that depredated only specific life stages (e.g. solely during the nest phase). The Red Fox and non-native mammals (e.g. the American Mink Neovison vison) were frequently identified as numerically limiting their prey species. Our review has identified predator-prey interactions that are particularly likely to result in population declines of prey species. In the short term, traditional predator-management techniques (e.g. lethal control or fencing to reduce predation by a small number of predator species) could be used to protect these vulnerable species. However, as these techniques are costly and time-consuming, we advocate that future research should identify land-use practices and landscape configurations that would reduce predator numbers and predation rates.
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Affiliation(s)
- Staffan Roos
- RSPB Centre for Conservation Science, Edinburgh, EH12 9DH, U.K
| | - Jennifer Smart
- RSPB Centre for Conservation Science, Sandy, SG19 2DL, U.K.,School of Biological Science, University of East Anglia, Norwich, NR4 7TJ, U.K
| | | | - Jeremy D Wilson
- RSPB Centre for Conservation Science, Edinburgh, EH12 9DH, U.K
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14
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Factors influencing the success of within-field AES fallow plots as key sites for the Northern Lapwing Vanellus vanellus in an industrialised agricultural landscape of Central Europe. J Nat Conserv 2017. [DOI: 10.1016/j.jnc.2016.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Laidlaw RA, Smart J, Smart MA, Gill JA. Scenarios of habitat management options to reduce predator impacts on nesting waders. J Appl Ecol 2016. [DOI: 10.1111/1365-2664.12838] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Rebecca A. Laidlaw
- School of Biological Sciences; University of East Anglia; Norwich Research Park Norwich NR4 7TJ UK
| | - Jennifer Smart
- RSPB Centre for Conservation Science; Royal Society for the Protection of Birds; The Lodge Sandy SG19 2DL UK
| | - Mark A. Smart
- Royal Society for the Protection of Birds; The Lodge Sandy SG19 2DL UK
| | - Jennifer A. Gill
- School of Biological Sciences; University of East Anglia; Norwich Research Park Norwich NR4 7TJ UK
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16
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Leigh SG, Smart J, Gill JA. Impacts of grassland management on wader nest predation rates in adjacent nature reserves. Anim Conserv 2016. [DOI: 10.1111/acv.12283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. G. Leigh
- School of Biological Sciences; University of East Anglia; Norwich UK
| | - J. Smart
- RSPB Centre for Conservation Science; Sandy UK
| | - J. A. Gill
- School of Biological Sciences; University of East Anglia; Norwich UK
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17
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Carpio AJ, Hillström L, Tortosa FS. Effects of wild boar predation on nests of wading birds in various Swedish habitats. EUR J WILDLIFE RES 2016. [DOI: 10.1007/s10344-016-1016-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Simple finite element methods for approximating predator-prey dynamics in two dimensions using MATLAB. Bull Math Biol 2015; 77:548-78. [PMID: 25616741 DOI: 10.1007/s11538-015-0062-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 01/05/2015] [Indexed: 10/24/2022]
Abstract
We describe simple finite element schemes for approximating spatially extended predator-prey dynamics with the Holling type II functional response and logistic growth of the prey. The finite element schemes generalize 'Scheme 1' in the paper by Garvie (Bull Math Biol 69(3):931-956, 2007). We present user-friendly, open-source MATLAB code for implementing the finite element methods on arbitrary-shaped two-dimensional domains with Dirichlet, Neumann, Robin, mixed Robin-Neumann, mixed Dirichlet-Neumann, and Periodic boundary conditions. Users can download, edit, and run the codes from http://www.uoguelph.ca/~mgarvie/ . In addition to discussing the well posedness of the model equations, the results of numerical experiments are presented and demonstrate the crucial role that habitat shape, initial data, and the boundary conditions play in determining the spatiotemporal dynamics of predator-prey interactions. As most previous works on this problem have focussed on square domains with standard boundary conditions, our paper makes a significant contribution to the area.
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