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Lo Parrino E, Ficetola GF, Devin M, Manenti R, Falaschi M. Integrating adult occurrence and reproduction data to identify conservation measures for amphibians. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024:e14343. [PMID: 39166831 DOI: 10.1111/cobi.14343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 04/09/2024] [Accepted: 05/04/2024] [Indexed: 08/23/2024]
Abstract
Monitoring programs are pivotal to establishing sound management. Due to economic, logistic, and time limitations, monitoring programs often overlook differences among life-history stages. However, species occurrence does not necessarily mean population viability, and it is unclear to what extent monitoring programs that do not consider separately adult presence and reproduction provide effective management indications. Unfortunately, collecting data on certain life stages requires high sampling effort, leading to a trade-off between model reliability and resources needed for monitoring. We collected data on presence and reproduction of amphibians by monitoring 207 waterbodies in Lombardy (northern Italy) in 2017-2022. We then used multistate occupancy models to test whether certain environmental features, namely, pond area, hydroperiod, forest cover, shade, aquatic vegetation, and predators' presence, differentially affected adult occurrence and breeding probabilities of multiple amphibian species. To assess optimal sampling efforts, we modeled the detection probabilities of adults and reproduction across multiple species. Finally, we identified the optimal monitoring strategy under different scenarios of resource availability, comparing adult-only monitoring versus joint assessment of the occurrence of adults and reproduction. In many cases, the main drivers of adult occurrence and reproduction did not coincide because most investigated ecological variables affected one life stage or the other. Forest area, for instance, increased occurrence probabilities of adults of the endemic Rana latastei but showed no effect on their reproduction probabilities. Quantitative estimates of the sampling effort showed that occurrence of adults was easier to spot in 4 out of 7 species. Multicriteria decision analyses showed that when resources were scarce, monitoring adults was the optimal strategy for those 4 species. Conversely, with more resources, monitoring both adults and reproduction emerged as the best strategy for all the considered species. Integrated monitoring of adults and reproduction is essential to comprehensively identify effective conservation measures for amphibians.
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Affiliation(s)
- Elia Lo Parrino
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, Laboratoire d'Écologie Alpine, Grenoble, France
| | - Michel Devin
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Raoul Manenti
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Mattia Falaschi
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
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2
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Coppari L, Di Gregorio M, Corti C, Merilli S, Mulargia M, Cogoni R, Manenti R, Ficetola GF, Lunghi E. Four years monitoring of the endangered European plethodontid salamanders. Sci Data 2024; 11:706. [PMID: 38937493 PMCID: PMC11211419 DOI: 10.1038/s41597-024-03555-y] [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: 02/26/2024] [Accepted: 06/19/2024] [Indexed: 06/29/2024] Open
Abstract
The ongoing biodiversity crisis is strongly threatening amphibians, mostly because of their peculiar physiology, their sensitivity to climate change and the spread of diseases. Effective monitoring involving assessments of pressure effects across time and estimation of population trends play a key role in mitigating amphibian decline. To improve implementation of standardized protocols and conservation efforts, we present here a dataset related to one of the amphibian genera whose onservation status is considered the most declining according to the IUCN. We report information on 66 populations of the endangered European cave salamanders, genus Speleomantes, that was collected through a standardized monitoring along a four-year period (2021-2024). Demographics data of the populations and fitness-related data of single individuals are reported. Furthermore, we include 3,836 high quality images of individuals that can allow to perform studies aiming to assess the phenotypic variability within the genus, and to perform long-term capture-mark-recaptured studies.
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Affiliation(s)
- Luca Coppari
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | | | - Claudia Corti
- Natural History Museum of the University of Firenze, Museo "La Specola", Firenze, Italy
- Speleo Club Firenze, Firenze, Italy
| | | | | | - Roberto Cogoni
- Unione Speleologica Cagliaritana, Quartu Sant'Elena, Cagliari, Italy
| | - Raoul Manenti
- Department of Environmental Science and Policy, University of Milano, Milano, Italy
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, University of Milano, Milano, Italy
- Laboratoire d'Écologie Alpine (LECA), University of Grenoble Alpes, CNRS, Grenoble, France
| | - Enrico Lunghi
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
- Natural Oasis, Prato, Italy.
- Unione Speleologica Calenzano, Calenzano (Florence), Italy.
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3
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Bollen M, Palencia P, Vicente J, Acevedo P, Del Río L, Neyens T, Beenaerts N, Casaer J. Assessing trends in population size of three unmarked species: A comparison of a multi-species N-mixture model and random encounter models. Ecol Evol 2023; 13:e10595. [PMID: 37841226 PMCID: PMC10570904 DOI: 10.1002/ece3.10595] [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: 06/07/2023] [Revised: 08/19/2023] [Accepted: 09/25/2023] [Indexed: 10/17/2023] Open
Abstract
Estimation of changes in abundances and densities is essential for the research, management, and conservation of animal populations. Recently, technological advances have facilitated the surveillance of animal populations through the adoption of passive sensors, such as camera traps (CT). Several methods, including the random encounter model (REM), have been developed for estimating densities of unmarked populations but require additional information. Hierarchical abundance models, such as the N-mixture model (NMM), can estimate abundances without performing additional fieldwork but do not explicitly estimate the area effectively sampled. This obscures the interpretation of its densities and requires its users to focus on relative measures of abundance instead. Hence, the main objective of our study is to evaluate if REM and NMM yield consistent results qualitatively. Therefore, we compare relative trends: (i) between species, (ii) between years and (iii) across years obtained from annual density/abundance estimates of three species (fox, wild boar and red deer) in central Spain monitored by a camera trapping network for five consecutive winter periods. We reveal that NMM and REM provided density estimates in the same order of magnitude for wild boar, but not for foxes and red deer. Assuming a Poisson detection process in the NMM was important to control for inflation of abundance estimates for frequently detected species. Both methods consistently ranked density/abundance across species (between species trend), but did not always agree on relative ranks of yearly estimates within a single population (between years trend), nor on its linear population trends across years (across years trend). Our results suggest that relative trends are generally consistent when the range of variability is large, but can become inconsistent when the range of variability is smaller.
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Affiliation(s)
- Martijn Bollen
- Centre for Environmental SciencesUHasselt – Hasselt UniversityDiepenbeekBelgium
- Data Science InstituteUHasselt – Hasselt UniversityDiepenbeekBelgium
- Research Institute for Nature and ForestBrusselsBelgium
| | - Pablo Palencia
- Instituto de Investigación en Recursos Cinegéticos (IREC)CSIC‐ UCLM‐ JCCMCiudad RealSpain
- Dipartamiento di Scienze VeterinarieUniversità Degli Studi di TorinoGrugliascoTorinoItaly
| | - Joaquín Vicente
- Instituto de Investigación en Recursos Cinegéticos (IREC)CSIC‐ UCLM‐ JCCMCiudad RealSpain
| | - Pelayo Acevedo
- Instituto de Investigación en Recursos Cinegéticos (IREC)CSIC‐ UCLM‐ JCCMCiudad RealSpain
| | - Lucía Del Río
- Instituto de Investigación en Recursos Cinegéticos (IREC)CSIC‐ UCLM‐ JCCMCiudad RealSpain
| | - Thomas Neyens
- Data Science InstituteUHasselt – Hasselt UniversityDiepenbeekBelgium
- Leuven Biostatistics and statistical Bioinformatics CentreKU LeuvenLeuvenBelgium
| | - Natalie Beenaerts
- Centre for Environmental SciencesUHasselt – Hasselt UniversityDiepenbeekBelgium
| | - Jim Casaer
- Research Institute for Nature and ForestBrusselsBelgium
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4
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Cogoni R, Di Gregorio M, Cianferoni F, Lunghi E. Monitoring of the Endangered Cave Salamander Speleomantes sarrabusensis. Animals (Basel) 2023; 13:ani13030391. [PMID: 36766280 PMCID: PMC9913285 DOI: 10.3390/ani13030391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/11/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
In this study, we performed the first monitoring activities on one of the most endangered amphibians in Europe, the Sette Fratelli cave salamander Speleomantes sarrabusensis. The data presented here are derived from two monitoring activities aiming to assess the status and abundance of four populations of S. sarrabusensis. With the first monitoring, we surveyed the well-known population occurring within artificial springs during the period 2015-2018, providing monthly data on the number of active individuals. With the second monitoring performed during spring to early summer of 2022, we surveyed four populations at three time points (the one from artificial springs and three from forested areas) and we provided the first estimation of the populations' abundance. Furthermore, we analyzed for the first time the stomach contents from a population of S. sarrabusensis only occurring in forested environments. With our study, we provided the first information on the abundance of different populations of S. sarrabusensis, representing the starting point for future status assessments for this endangered species.
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Affiliation(s)
- Roberto Cogoni
- Unione Speleologica Cagliaritana, Quartu Sant’Elena, 09045 Cagliari, Italy
| | - Milos Di Gregorio
- Dipartimento di Biologia, Università degli Studi di Pisa, 56126 Pisa, Italy
- Correspondence:
| | - Fabio Cianferoni
- Istituto di Ricerca sugli Ecosistemi Terrestri (IRET), Consiglio Nazionale delle Ricerche (CNR), Sesto Fiorentino, 50019 Firenze, Italy
- Museo di Storia Naturale dell’Università degli Studi di Firenze, “La Specola”, 50125 Firenze, Italy
| | - Enrico Lunghi
- Dipartimento di Medicina Clinica, Sanità Pubblica, Scienze Della Vita e dell’ambiente (MeSVA), Universià degli Studi dell’Aquila, 67100 L’Aquila, Italy
- Associazione Natural Oasis, 59100 Prato, Italy
- Unione Speleologica Calenzano, 50041 Calenzano, Italy
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5
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A Bayesian approach for multiscale modeling of the influence of seasonal and annual habitat variation on relative abundance of ring-necked pheasant roosters. ECOL INFORM 2023. [DOI: 10.1016/j.ecoinf.2023.102003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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6
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Newman KD, Nelson JL, Durkin LK, Cripps JK, McCarthy MA. An analytical solution for optimising detections when accounting for site establishment costs. Ecol Modell 2022. [DOI: 10.1016/j.ecolmodel.2022.110117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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7
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Falaschi M, Gibertini C, Lo Parrino E, Muraro M, Barzaghi B, Manenti R, Ficetola GF. Assessing Population Trends of Species with Imperfect Detection: Double Count Analyses and Simulations Confirm Reliable Estimates in Brown Frogs. Animals (Basel) 2022; 12:ani12162085. [PMID: 36009675 PMCID: PMC9405163 DOI: 10.3390/ani12162085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/25/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022] Open
Abstract
Most animal species are detected imperfectly and overlooking individuals can result in a biased inference of the abundance patterns and underlying processes. Several techniques can incorporate the imperfect detection process for a more accurate estimation of abundance, but most of them require repeated surveys, i.e., more sampling effort compared to single counts. In this study, we used the dependent double-observer approach to estimate the detection probability of the egg clutches of two brown frog species, Rana dalmatina and R. latastei. We then simulated the data of a declining population at different levels of detection probability in order to assess under which conditions the double counts provided better estimates of population trends compared to naïve egg counts, given the detectability of frog clutches. Both species showed a very high detection probability, with average values of 93% for Rana dalmatina and 97% for R. latastei. Simulations showed that not considering imperfect detection reduces the power of detecting population trends if detection probability is low. However, at high detection probability (>80%), ignoring the imperfect detection does not bias the estimates of population trends. This suggests that, for species laying large and easily identifiable egg clutches, a single count can provide useful estimates if surveys are correctly timed.
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Affiliation(s)
- Mattia Falaschi
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
| | - Chiara Gibertini
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
- Correspondence:
| | - Elia Lo Parrino
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
| | - Martina Muraro
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
| | - Benedetta Barzaghi
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
| | - Raoul Manenti
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, University of Milan, Via Celoria 10, 20133 Milan, Italy
- Laboratoire d’Écologie Alpine, University Grenoble Alpes, University Savoie Mont Blanc, CNRS, LECA, F-38000 Grenoble, France
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8
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Toad invasion of Malagasy forests triggers severe mortality of a predatory snake. Biol Invasions 2022. [DOI: 10.1007/s10530-021-02708-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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9
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Urban MC, Travis JMJ, Zurell D, Thompson PL, Synes NW, Scarpa A, Peres-Neto PR, Malchow AK, James PMA, Gravel D, De Meester L, Brown C, Bocedi G, Albert CH, Gonzalez A, Hendry AP. Coding for Life: Designing a Platform for Projecting and Protecting Global Biodiversity. Bioscience 2021. [DOI: 10.1093/biosci/biab099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Time is running out to limit further devastating losses of biodiversity and nature's contributions to humans. Addressing this crisis requires accurate predictions about which species and ecosystems are most at risk to ensure efficient use of limited conservation and management resources. We review existing biodiversity projection models and discover problematic gaps. Current models usually cannot easily be reconfigured for other species or systems, omit key biological processes, and cannot accommodate feedbacks with Earth system dynamics. To fill these gaps, we envision an adaptable, accessible, and universal biodiversity modeling platform that can project essential biodiversity variables, explore the implications of divergent socioeconomic scenarios, and compare conservation and management strategies. We design a roadmap for implementing this vision and demonstrate that building this biodiversity forecasting platform is possible and practical.
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Affiliation(s)
- Mark C Urban
- University of Connecticut, Storrs, Connecticut, United States
| | | | | | | | | | - Alice Scarpa
- University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | | | | | | | | | - Luc De Meester
- Laboratory of Aquatic Ecology, Evolution, and Conservation, KU Leuven, Leuven, Belgium, with the Leibniz-Institut für Gewässerökologie und Binnenfischerei, Berlin, Germany, and with the Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Calum Brown
- IMK-IFU, Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
| | - Greta Bocedi
- University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Cécile H Albert
- Aix Marseille Univ, CNRS, Univ Avignon, IRD, IMBE, Marseille, France
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10
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Ficetola GF, Silva-Rocha I, Carretero MA, Vignoli L, Sacchi R, Melotto A, Scali S, Salvi D. Status of the largest extant population of the critically endangered Aeolian lizard Podarcis raffonei (Capo Grosso, Vulcano island). PLoS One 2021; 16:e0253631. [PMID: 34161384 PMCID: PMC8221524 DOI: 10.1371/journal.pone.0253631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022] Open
Abstract
The Aeolian wall lizard Podarcis raffonei is an island endemic that survives only on three tiny islets, and on the Capo Grosso peninsula of the Vulcano island, thus is among the European vertebrates with the smallest range and one of the most threatened by extinction. This species is declining due to competition and hybridization with the non-native lizard Podarcis siculus, but a regular monitoring program is lacking. Here we assessed the size and status of the Capo Grosso population of P. raffonei on Vulcano. In September 2015 we captured 30 individuals showing the typical brown phenotype of P. raffonei, while one single male showed a green phenotype, apparently intermediate between P. raffonei and the non-native Podarcis siculus. In May 2017, only 47% of 131 individuals showed the typical brown phenotype (P. raffonei-like) and 53% showed the green phenotype (P. siculus-like). Based on N-mixture models and removal sampling the estimated size of the Capo Grosso population was of 800–1300 individuals in 2017, being similar to 2015; available data suggest that the total range of the species could be as small as 2 ha. The frequency of individuals with the typical P. raffonei phenotype dramatically dropped between two samplings with a parallel increase of individuals displaying the green phenotype. Observation on outdoor captive-bred individuals demonstrates plasticity for colouration in P. raffonei individuals from Capo Grosso, with several individuals showing the typical brown pattern in September 2017 and a green pattern in March 2021. Non-exclusive hypotheses, including hybridization with P. siculus and plasticity in colour pattern of P. raffonei, are discussed to explain the phenotypic shifts of the P. raffonei population of Capo Grosso. While genomic evidence is required to reach conclusions and investigate eventual hybridization, it is urgent to undertake a programme for the monitoring and management of this lizard.
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Affiliation(s)
- Gentile Francesco Ficetola
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milano, Italy
- CNRS, Laboratoire d’Ecologie Alpine (LECA), Univ. Grenoble Alpes, Grenoble, France
| | - Iolanda Silva-Rocha
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, InBio Laboratório Associado, Vairão, Portugal
| | - Miguel A. Carretero
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, InBio Laboratório Associado, Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | | | - Roberto Sacchi
- Department of Earth and Environmental Sciences, University of Pavia, Pavia, Italy
| | - Andrea Melotto
- Centre of Excellence for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | | | - Daniele Salvi
- Department of Health, Life and Environmental Sciences, University of L’Aquila, Via Vetoio, L’Aquila, Italy
- * E-mail:
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11
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Fandos G, Kéry M, Cano‐Alonso LS, Carbonell I, Luis Tellería J. Dynamic multistate occupancy modeling to evaluate population dynamics under a scenario of preferential sampling. Ecosphere 2021. [DOI: 10.1002/ecs2.3469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Guillermo Fandos
- Ecology and Macroecology University of Potsdam Am Mühlenberg 3 Potsdam14469Germany
- Geography Department Humboldt‐Universitat zu Berlin Berlin Germany
- Departamento de Biodiversidad, Ecología y Evolución Facultad de Ciencias Biológicas Universidad Complutense Madrid28040Spain
| | - Marc Kéry
- Swiss Ornithological Institute Seerose 1 Sempach6204Switzerland
| | - Luis Santiago Cano‐Alonso
- Departamento de Biodiversidad, Ecología y Evolución Facultad de Ciencias Biológicas Universidad Complutense Madrid28040Spain
- IUCN SSC Stork, Ibis and Spoonbill Specialist Group. Rue Mauverney 28 Gland1196Switzerland
| | | | - José Luis Tellería
- Departamento de Biodiversidad, Ecología y Evolución Facultad de Ciencias Biológicas Universidad Complutense Madrid28040Spain
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12
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Vallecillo D, Gauthier‐Clerc M, Guillemain M, Vittecoq M, Vandewalle P, Roche B, Champagnon J. Reliability of animal counts and implications for the interpretation of trends. Ecol Evol 2021; 11:2249-2260. [PMID: 33717452 PMCID: PMC7920765 DOI: 10.1002/ece3.7191] [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: 06/15/2020] [Revised: 11/17/2020] [Accepted: 12/18/2020] [Indexed: 11/24/2022] Open
Abstract
Population time series analysis is an integral part of conservation biology in the current context of global changes. To quantify changes in population size, wildlife counts only provide estimates because of various sources of error. When unaccounted for, such errors can obscure important ecological patterns and reduce confidence in the derived trend. In the case of highly gregarious species, which are common in the animal kingdom, the estimation of group size is an important potential bias, which is characterized by high variance among observers. In this context, it is crucial to quantify the impact of observer changes, inherent to population monitoring, on i) the minimum length of population time series required to detect significant trends and ii) the accuracy (bias and precision) of the trend estimate.We acquired group size estimation error data by an experimental protocol where 24 experienced observers conducted counting simulation tests on group sizes. We used this empirical data to simulate observations over 25 years of a declining population distributed over 100 sites. Five scenarios of changes in observer identity over time and sites were tested for each of three simulated trends (true population size evolving according to deterministic models parameterized with declines of 1.1%, 3.9% or 7.4% per year that justify respectively a "declining," "vulnerable" or "endangered" population under IUCN criteria).We found that under realistic field conditions observers detected the accurate value of the population trend in only 1.3% of the cases. Our results also show that trend estimates are similar if many observers are spatially distributed among the different sites, or if one single observer counts all sites. However, successive changes in observer identity over time lead to a clear decrease in the ability to reliably estimate a given population trend, and an increase in the number of years of monitoring required to adequately detect the trend.Minimizing temporal changes of observers improve the quality of count data and help taking appropriate management decisions and setting conservation priorities. The same occurs when increasing the number of observers spread over 100 sites. If the population surveyed is composed of few sites, then it is preferable to perform the survey by one observer. In this context, it is important to reconsider how we use estimated population trend values and potentially to scale our decisions according to the direction and duration of estimated trends, instead of setting too precise threshold values before action.
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Affiliation(s)
- David Vallecillo
- Tour du ValatResearch institute for the conservation of Mediterranean wetlandsArlesFrance
- OFBUnité Avifaune migratriceLa Tour du ValatArlesFrance
| | | | | | - Marion Vittecoq
- Tour du ValatResearch institute for the conservation of Mediterranean wetlandsArlesFrance
| | | | - Benjamin Roche
- IRDSorbonne UniversitéUMMISCOBondyFrance
- MIVEGEC, IRDCNRSUniversité MontpellierMontpellierFrance
- Departamento de EtologíaFauna Silvestre y Animales de LaboratorioFacultad de Medicina Veterinaria y ZootecniaUniversidad Nacional Autónoma de México (UNAM)Ciudad de MéxicoMéxico
| | - Jocelyn Champagnon
- Tour du ValatResearch institute for the conservation of Mediterranean wetlandsArlesFrance
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13
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Costa A, Salvidio S, Penner J, Basile M. Time-for-space substitution in N-mixture models for estimating population trends: a simulation-based evaluation. Sci Rep 2021; 11:4581. [PMID: 33633209 PMCID: PMC7907346 DOI: 10.1038/s41598-021-84010-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 02/10/2021] [Indexed: 11/15/2022] Open
Abstract
N-mixture models usually rely on a meta-population design, in which repeated counts of individuals in multiple sampling locations are obtained over time. The time-for-space substitution (TSS) in N-mixture models allows to estimate population abundance and trend of a single population, without spatial replication. This application could be of great interest in ecological studies and conservation programs; however, its reliability has only been evaluated on a single case study. Here we perform a simulation-based evaluation of this particular application of N-mixture modelling. We generated count data, under 144 simulated scenarios, from a single population surveyed several times per year and subject to different dynamics. We compared simulated abundance and trend values with TSS estimates. TSS estimates are overall in good agreement with real abundance. Trend and abundance estimation is mainly affected by detection probability and population size. After evaluating the reliability of TSS, both against real world data, and simulations, we suggest that this particular application of N-mixture model could be reliable for monitoring abundance in single populations of rare or difficult to study species, in particular in cases of species with very narrow geographic ranges, or known only for few localities.
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Affiliation(s)
- Andrea Costa
- Department of Earth and Life Sciences (DISTAV), University of Genova, Corso Europa 26, 16132, Genova, Italy
| | - Sebastiano Salvidio
- Department of Earth and Life Sciences (DISTAV), University of Genova, Corso Europa 26, 16132, Genova, Italy
| | - Johannes Penner
- Chair of Wildlife Ecology and Management, University of Freiburg, Tennenbacher Str. 4, 79106, Freiburg, Germany
| | - Marco Basile
- Chair of Wildlife Ecology and Management, University of Freiburg, Tennenbacher Str. 4, 79106, Freiburg, Germany.
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14
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Perkins NR, Prall M, Chakraborty A, White JW, Baskett ML, Morgan SG. Quantifying the statistical power of monitoring programs for marine protected areas. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e2215. [PMID: 32767487 DOI: 10.1002/eap.2215] [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: 07/08/2019] [Revised: 04/15/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
Marine Protected Areas (MPAs) are increasingly established globally as a spatial management tool to aid in conservation and fisheries management objectives. Assessing whether MPAs are having the desired effects on populations requires effective monitoring programs. A cornerstone of an effective monitoring program is an assessment of the statistical power of sampling designs to detect changes when they occur. We present a novel approach to power assessment that combines spatial point process models, integral projection models (IPMs) and sampling simulations to assess the power of different sample designs across a network of MPAs. We focus on the use of remotely operated vehicle (ROV) video cameras as the sampling method, though the results could be extended to other sampling methods. We use empirical data from baseline surveys of an example indicator fish species across three MPAs in California, USA as a case study. Spatial models simulated time series of spatial distributions across sites that accounted for the effects of environmental covariates, while IPMs simulated expected trends over time in abundances and sizes of fish. We tested the power of different levels of sampling effort (i.e., the number of 500-m ROV transects) and temporal replication (every 1-3 yr) to detect expected post-MPA changes in fish abundance and biomass. We found that changes in biomass are detectable earlier than changes in abundance. We also found that detectability of MPA effects was higher in sites with higher initial densities. Increasing the sampling effort had a greater effect than increasing sampling frequency on the time taken to achieve high power. High power was best achieved by combining data from multiple sites. Our approach provides a powerful tool to explore the interaction between sampling effort, spatial distributions, population dynamics, and metrics for detecting change in previously fished populations.
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Affiliation(s)
- Nicholas R Perkins
- Coastal and Marine Sciences Institute, University of California, Davis, California, 95616, USA
- California Department of Fish and Wildlife, Marine Region, Eureka, California, 95501, USA
- Institute of Marine and Antarctic Studies, University of Tasmania, Taroona, Tasmania, 7053, Australia
| | - Michael Prall
- California Department of Fish and Wildlife, Marine Region, Eureka, California, 95501, USA
| | - Avishek Chakraborty
- Department of Mathematical Sciences, University of Arkansas, Fayetteville, Arkansas, 72701, USA
| | - J Wilson White
- Department of Fisheries and Wildlife, Coastal Oregon Marine Experiment Station, Oregon State University, Newport, Oregon, 97365, USA
| | - Marissa L Baskett
- Department of Environmental Science & Policy, University of California, Davis, California, 95616, USA
| | - Steven G Morgan
- Department of Environmental Science & Policy, University of California, Davis, California, 95616, USA
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15
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Di Muri C, Lawson Handley L, Bean CW, Li J, Peirson G, Sellers GS, Walsh K, Watson HV, Winfield IJ, Hänfling B. Read counts from environmental DNA (eDNA) metabarcoding reflect fish abundance and biomass in drained ponds. METABARCODING AND METAGENOMICS 2020. [DOI: 10.3897/mbmg.4.56959] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The sampling of environmental DNA (eDNA) coupled with cost-efficient and ever-advancing sequencing technology is propelling changes in biodiversity monitoring within aquatic ecosystems. Despite the increasing number of eDNA metabarcoding approaches, the ability to quantify species biomass and abundance in natural systems is still not fully understood. Previous studies have shown positive but sometimes weak correlations between abundance estimates from eDNA metabarcoding data and from conventional capture methods. As both methods have independent biases a lack of concordance is difficult to interpret. Here we tested whether read counts from eDNA metabarcoding provide accurate quantitative estimates of the absolute abundance of fish in holding ponds with known fish biomass and number of individuals. Environmental DNA samples were collected from two fishery ponds with high fish density and broad species diversity. In one pond, two different DNA capture strategies (on-site filtration with enclosed filters and three different preservation buffers versus lab filtration using open filters) were used to evaluate their performance in relation to fish community composition and biomass/abundance estimates. Fish species read counts were significantly correlated with both biomass and abundance, and this result, together with information on fish diversity, was repeatable when open or enclosed filters with different preservation buffers were used. This research demonstrates that eDNA metabarcoding provides accurate qualitative and quantitative information on fish communities in small ponds, and results are consistent between different methods of DNA capture. This method flexibility will be beneficial for future eDNA-based fish monitoring and their integration into fisheries management.
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16
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Lunghi E, Corti C, Mulargia M, Zhao Y, Manenti R, Ficetola GF, Veith M. Cave morphology, microclimate and abundance of five cave predators from the Monte Albo (Sardinia, Italy). Biodivers Data J 2020; 8:e48623. [PMID: 32076380 PMCID: PMC7010837 DOI: 10.3897/bdj.8.e48623] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/16/2019] [Indexed: 12/21/2022] Open
Abstract
Background Systematic data collection on species and their exploited environments is of key importance for conservation studies. Within the less-known environments, the subterranean ones are neither easy to be studied, nor to be explored. Subterranean environments house a wide number of specialised organisms, many of which show high sensitivity to habitat alteration. Despite the undeniable importance to monitor the status of the subterranean biodiversity, standardised methodologies to record biotic and abiotic data in these environments are still not fully adopted, impeding therefore the creation of comparable datasets useful for monitoring the ecological condition in the subterranean environments and for conservation assessment of related species. New information In this work we describe a methodology allowing the collection of standardised abiotic and biotic data in subterranean environments. To show this, we created a large dataset including information on environmental features (morphology and microclimate) and abundance of five predators (one salamander, three spiders and one snail) occurring in seven caves of the Monte Albo (Sardinia, Italy), an important biodiversity hotspot. We performed 77 surveys on 5,748 m2 of subterranean environments througout a year, recording 1,695 observations of the five cave predators. The fine-scale data collection adopted in our methodology allowed us to record detailed information related to both morphology and microclimate of the cave inner environment. Furthermore, this method allows us to account for species-imperfect detection when recording presence/abundance data.
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Affiliation(s)
- Enrico Lunghi
- Key Laboratory of the Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China Key Laboratory of the Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences Beijing China.,Museo di Storia Naturale dell'Università degli Studi di Firenze, "La Specola", Firenze, Italy Museo di Storia Naturale dell'Università degli Studi di Firenze, "La Specola" Firenze Italy.,Universität Trier Fachbereich VI Raum-und Umweltwissenschaften Biogeographie, Trier, Germany Universität Trier Fachbereich VI Raum-und Umweltwissenschaften Biogeographie Trier Germany
| | - Claudia Corti
- Museo di Storia Naturale dell'Università degli Studi di Firenze, "La Specola", Firenze, Italy Museo di Storia Naturale dell'Università degli Studi di Firenze, "La Specola" Firenze Italy
| | - Manuela Mulargia
- CEAS Santa Lucia, Siniscola, Italy CEAS Santa Lucia Siniscola Italy
| | - Yahui Zhao
- Key Laboratory of the Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China Key Laboratory of the Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences Beijing China
| | - Raoul Manenti
- Department of Environmental Sciences and Policy, Università degli Studi di Milano, Milano, Italy Department of Environmental Sciences and Policy, Università degli Studi di Milano Milano Italy
| | - Gentile Francesco Ficetola
- Department of Environmental Sciences and Policy, Università degli Studi di Milano, Milano, Italy Department of Environmental Sciences and Policy, Università degli Studi di Milano Milano Italy.,Université Grenoble Alpes, CNRS,, Grenoble, France Université Grenoble Alpes, CNRS, Grenoble France.,LECA, Laboratoire d'Ecologie Alpine, Grenoble, France LECA, Laboratoire d'Ecologie Alpine Grenoble France.,Université Savoie Mont Blanc, Annecy, France Université Savoie Mont Blanc Annecy France
| | - Michael Veith
- Universität Trier Fachbereich VI Raum-und Umweltwissenschaften Biogeographie, Trier, Germany Universität Trier Fachbereich VI Raum-und Umweltwissenschaften Biogeographie Trier Germany
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17
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Andersen EM, Steidl RJ. Power to detect trends in abundance within a distance sampling framework. J Appl Ecol 2019. [DOI: 10.1111/1365-2664.13529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Erik M. Andersen
- School of Natural Resources and the Environment University of Arizona Tucson AZ USA
| | - Robert J. Steidl
- School of Natural Resources and the Environment University of Arizona Tucson AZ USA
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18
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Falaschi M, Manenti R, Thuiller W, Ficetola GF. Continental-scale determinants of population trends in European amphibians and reptiles. GLOBAL CHANGE BIOLOGY 2019; 25:3504-3515. [PMID: 31220393 DOI: 10.1111/gcb.14739] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 05/29/2019] [Accepted: 06/13/2019] [Indexed: 06/09/2023]
Abstract
The continuous decline of biodiversity is determined by the complex and joint effects of multiple environmental drivers. Still, a large part of past global change studies reporting and explaining biodiversity trends have focused on a single driver. Therefore, we are often unable to attribute biodiversity changes to different drivers, since a multivariable design is required to disentangle joint effects and interactions. In this work, we used a meta-regression within a Bayesian framework to analyze 843 time series of population abundance from 17 European amphibian and reptile species over the last 45 years. We investigated the relative effects of climate change, alien species, habitat availability, and habitat change in driving trends of population abundance over time, and evaluated how the importance of these factors differs across species. A large number of populations (54%) declined, but differences between species were strong, with some species showing positive trends. Populations declined more often in areas with a high number of alien species, and in areas where climate change has caused loss of suitability. Habitat features showed small variation over the last 25 years, with an average loss of suitable habitat of 0.1%/year per population. Still, a strong interaction between habitat availability and the richness of alien species indicated that the negative impact of alien species was particularly strong for populations living in landscapes with less suitable habitat. Furthermore, when excluding the two commonest species, habitat loss was the main correlate of negative population trends for the remaining species. By analyzing trends for multiple species across a broad spatial scale, we identify alien species, climate change, and habitat changes as the major drivers of European amphibian and reptile decline.
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Affiliation(s)
- Mattia Falaschi
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Raoul Manenti
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Wilfried Thuiller
- Laboratoire d'Écologie Alpine (LECA), Université Grenoble Alpes, University of Savoie Mont Blanc, CNRS, Grenoble, France
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
- Laboratoire d'Écologie Alpine (LECA), Université Grenoble Alpes, University of Savoie Mont Blanc, CNRS, Grenoble, France
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19
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Baker DJ, Clarke RH, McGeoch MA. The power to detect regional declines in common bird populations using continental monitoring data. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01918. [PMID: 31162764 DOI: 10.1002/eap.1918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 04/08/2019] [Accepted: 04/17/2019] [Indexed: 06/09/2023]
Abstract
Anthropogenic environmental change is driving the rapid loss of biodiversity. Large declines in the abundance of historically common species are now emerging as a major concern. Identifying declining populations through long-term biodiversity monitoring is vital for implementing timely conservation measures. It is, therefore, critical to evaluate the likelihood that persistent long-term population trends of a given size could be detected using existing monitoring data and methods. Here, we test the power to detect declines in Australia's common landbirds using long-term citizen science monitoring. We use spatially explicit simulations of occupancy dynamics and virtual sampling, designed to mimic bird monitoring in better-sampled regions of Australia, to assess likely power in these data to detect trends relevant for conservation. We predict the statistical power for 326 common species that meet minimum requirements for monitoring data across 10 regions of Australia, estimating the number of species for which we would have a high (≥80%) chance of detecting declines of different sizes. The power to detect declines of ≥30% per decade was predicted to be high for at least one-third of the common species in 7 of 10 regions, with a total of 103 (32% of 326) unique species sufficiently monitored in at least one region. These species spanned 12 taxonomic orders, four orders of magnitude in body mass, and a broad diversity of dietary guilds, suggesting the current species pool will likely serve as robust indicators for a broad range of environmental states and pressures. Power was strongly affected by species' detectability, and power to detect even large declines was negligible when species are detected on ≤50% of visits to an occupied site. Predicted power for many species fell just short of the 80% threshold in one or more regions, which suggests an increase in effort targeting these species could greatly enhance the species and regional representation of these data. Against the backdrop of unprecedented biodiversity losses, this study shows how critical evaluation of existing monitoring schemes is valuable both for assessing the contribution of citizen science schemes to biodiversity monitoring and for designing strategic monitoring to significantly improve the knowledge these schemes provide.
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Affiliation(s)
- D J Baker
- School of Biological Sciences, Monash University, Melbourne, Victoria, 3800, Australia
| | - R H Clarke
- School of Biological Sciences, Monash University, Melbourne, Victoria, 3800, Australia
| | - M A McGeoch
- School of Biological Sciences, Monash University, Melbourne, Victoria, 3800, Australia
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20
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Costa A, Oneto F, Salvidio S. Time‐for‐space substitution in
N
‐mixture modeling and population monitoring. J Wildl Manage 2019. [DOI: 10.1002/jwmg.21621] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andrea Costa
- Dipartimento di Scienze della Terra dell'Ambiente e della Vita (DISTAV)Università degli Studi di GenovaGenovaItaly
| | - Fabrizio Oneto
- Dipartimento di Scienze della Terra dell'Ambiente e della Vita (DISTAV)Università degli Studi di GenovaGenovaItaly
| | - Sebastiano Salvidio
- Dipartimento di Scienze della Terra dell'Ambiente e della Vita (DISTAV)Università degli Studi di GenovaGenovaItaly
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21
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Licata F, Ficetola GF, Freeman K, Mahasoa RH, Ravololonarivo V, Solofo Niaina Fidy JF, Koto-Jean AB, Nahavitatsara ER, Andreone F, Crottini A. Abundance, distribution and spread of the invasive Asian toad Duttaphrynus melanostictus in eastern Madagascar. Biol Invasions 2019. [DOI: 10.1007/s10530-019-01920-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Chen W, Ficetola GF. Conditionally autoregressive models improve occupancy analyses of autocorrelated data: An example with environmental DNA. Mol Ecol Resour 2018; 19:163-175. [DOI: 10.1111/1755-0998.12949] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 09/12/2018] [Accepted: 09/14/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Wentao Chen
- Laboratoire d’Écologie Alpine (LECA) CNRS Univ. Grenoble Alpes Grenoble France
| | - Gentile Francesco Ficetola
- Laboratoire d’Écologie Alpine (LECA) CNRS Univ. Grenoble Alpes Grenoble France
- Department of Environmental Science and Policy Università degli Studi di Milano Milano Italy
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23
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Morán‐Ordóñez A, Canessa S, Bota G, Brotons L, Herrando S, Hermoso V. Efficiency of species survey networks can be improved by integrating different monitoring approaches in a spatial prioritization design. Conserv Lett 2018. [DOI: 10.1111/conl.12591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
- Alejandra Morán‐Ordóñez
- Biodiversity and Landscape Ecology lab, Centre de Ciència i Tecnologia Forestal de Catalunya (CTFC) Solsona Catalonia Spain
- Centre for Research on Ecology and Forestry Applications (CREAF) Cerdanyola del Valles Catalonia Spain
| | - Stefano Canessa
- Wildlife Health Ghent, Faculty of Veterinary MedicineDepartment of Pathology, Bacteriology and Avian Diseases, Ghent University Merelbeke Belgium
| | - Gerard Bota
- Biodiversity and Landscape Ecology lab, Centre de Ciència i Tecnologia Forestal de Catalunya (CTFC) Solsona Catalonia Spain
| | - Lluis Brotons
- Biodiversity and Landscape Ecology lab, Centre de Ciència i Tecnologia Forestal de Catalunya (CTFC) Solsona Catalonia Spain
- Centre for Research on Ecology and Forestry Applications (CREAF) Cerdanyola del Valles Catalonia Spain
- Spanish National Research Council (CSIC) Cerdanyola del Valles Catalonia Spain
| | - Sergi Herrando
- Natural History Museum of Barcelona, Catalan Ornithological Institute (ICO) Barcelona Catalonia Spain
| | - Virgilio Hermoso
- Biodiversity and Landscape Ecology lab, Centre de Ciència i Tecnologia Forestal de Catalunya (CTFC) Solsona Catalonia Spain
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24
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Ficetola GF, Barzaghi B, Melotto A, Muraro M, Lunghi E, Canedoli C, Lo Parrino E, Nanni V, Silva-Rocha I, Urso A, Carretero MA, Salvi D, Scali S, Scarì G, Pennati R, Andreone F, Manenti R. N-mixture models reliably estimate the abundance of small vertebrates. Sci Rep 2018; 8:10357. [PMID: 29985399 PMCID: PMC6037707 DOI: 10.1038/s41598-018-28432-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 06/22/2018] [Indexed: 11/23/2022] Open
Abstract
Accurate measures of species abundance are essential to identify conservation strategies. N-mixture models are increasingly used to estimate abundance on the basis of species counts. In this study we tested whether abundance estimates obtained using N-mixture models provide consistent results with more traditional approaches requiring capture (capture-mark recapture and removal sampling). We focused on endemic, threatened species of amphibians and reptiles in Italy, for which accurate abundance data are needed for conservation assessments: the Lanza’s Alpine salamander Salamandra lanzai, the Ambrosi’s cave salamander Hydromantes ambrosii and the Aeolian wall lizard Podarcis raffonei. In visual counts, detection probability was variable among species, ranging between 0.14 (Alpine salamanders) and 0.60 (cave salamanders). For all the species, abundance estimates obtained using N-mixture models showed limited differences with the ones obtained through capture-mark-recapture or removal sampling. The match was particularly accurate for cave salamanders in sites with limited abundance and for lizards, nevertheless non-incorporating heterogeneity of detection probability increased bias. N-mixture models provide reliable abundance estimates that are comparable with the ones of more traditional approaches, and offer additional advantages such as a smaller sampling effort and no need of manipulating individuals, which in turn reduces the risk of harming animals and spreading diseases.
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Affiliation(s)
- Gentile Francesco Ficetola
- Department of Environmental Science and Policy, University of Milan, Milano, Italy. .,Laboratoire d'Ecologie Alpine (LECA), CNRS, Université Grenoble Alpes, Grenoble, France.
| | - Benedetta Barzaghi
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Andrea Melotto
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Martina Muraro
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Enrico Lunghi
- Universität Trier Fachbereich VI Raum-und Umweltwissenschaften Biogeographie, Universitätsring 15, 54286, Trier, Germany.,Museo di Storia Naturale dell'Università di Firenze, Sezione di Zoologia "La Specola", Via Romana 17, 50125, Firenze, Italy.,Natural Oasis, Via di Galceti 141, 59100, Prato, Italy
| | - Claudia Canedoli
- DISAT, Università degli Studi di Milano-Bicocca. Piazza della Scienza 1, 20126, Milano, Italy
| | - Elia Lo Parrino
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Veronica Nanni
- Department of Earth, Environmental and Life Science (DISTAV), University of Genoa, Genova, Italy
| | - Iolanda Silva-Rocha
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Campus de Vairão. 4485-661, Universidade do Porto, Vairão, Vila do Conde, Portugal
| | - Arianna Urso
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Miguel Angel Carretero
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Campus de Vairão. 4485-661, Universidade do Porto, Vairão, Vila do Conde, Portugal
| | - Daniele Salvi
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Campus de Vairão. 4485-661, Universidade do Porto, Vairão, Vila do Conde, Portugal.,Department of Health, Life and Environmental Sciences, University of L'Aquila, 67100, Coppito, L'Aquila, Italy
| | - Stefano Scali
- Museo di Storia Naturale di Milano, Corso Venezia 55, I-20121, Milano, Italy
| | - Giorgio Scarì
- Department of Biosciences, University of Milan, Milano, Italy
| | - Roberta Pennati
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
| | - Franco Andreone
- Museo Regionale di Scienze Naturali, Via G. Giolitti, 36, I-10123, Torino, Italy
| | - Raoul Manenti
- Department of Environmental Science and Policy, University of Milan, Milano, Italy
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25
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Lunghi E, Manenti R, Mulargia M, Veith M, Corti C, Ficetola GF. Environmental suitability models predict population density, performance and body condition for microendemic salamanders. Sci Rep 2018; 8:7527. [PMID: 29760473 PMCID: PMC5951833 DOI: 10.1038/s41598-018-25704-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/25/2018] [Indexed: 11/30/2022] Open
Abstract
Species can show strong variation of local abundance across their ranges. Recent analyses suggested that variation in abundance can be related to environmental suitability, as the highest abundances are often observed in populations living in the most suitable areas. However, there is limited information on the mechanisms through which variation in environmental suitability determines abundance. We analysed populations of the microendemic salamander Hydromantes flavus, and tested several hypotheses on potential relationships linking environmental suitability to population parameters. For multiple populations across the whole species range, we assessed suitability using species distribution models, and measured density, activity level, food intake and body condition index. In high-suitability sites, the density of salamanders was up to 30-times higher than in the least suitable ones. Variation in activity levels and population performance can explain such variation of abundance. In high-suitability sites, salamanders were active close to the surface, and showed a low frequency of empty stomachs. Furthermore, when taking into account seasonal variation, body condition was better in the most suitable sites. Our results show that the strong relationship between environmental suitability and population abundance can be mediated by the variation of parameters strongly linked to individual performance and fitness.
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Affiliation(s)
- Enrico Lunghi
- Biogeographie, Universität Trier Fachbereich VI, Raum- und Umweltwissenschaften, Trier, Germany. .,Museo di Storia Naturale dell'Università degli Studi di Firenze, Sezione di Zoologia "La Specola", Firenze, Italy. .,Natural Oasis, Prato, Italy.
| | - Raoul Manenti
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milano, Italy
| | | | - Michael Veith
- Biogeographie, Universität Trier Fachbereich VI, Raum- und Umweltwissenschaften, Trier, Germany
| | - Claudia Corti
- Museo di Storia Naturale dell'Università degli Studi di Firenze, Sezione di Zoologia "La Specola", Firenze, Italy
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milano, Italy.,University Grenoble Alpes, CNRS, Laboratoire d'Écologie Alpine (LECA), F-38000, Grenoble, France
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26
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Direct Observation of Dog Density and Composition during Street Counts as a Resource Efficient Method of Measuring Variation in Roaming Dog Populations over Time and between Locations. Animals (Basel) 2017; 7:ani7080057. [PMID: 28771177 PMCID: PMC5575569 DOI: 10.3390/ani7080057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/21/2017] [Accepted: 07/28/2017] [Indexed: 11/17/2022] Open
Abstract
Dog population management is conducted in many countries to address the public health risks from roaming dogs and threats to their welfare. To assess its effectiveness, we need to monitor indicators from both the human and dog populations that are quick and easy to collect, precise and meaningful to intervention managers, donors and local citizens. We propose that the most appropriate indicators from the roaming dog population are population density and composition, based on counting dogs along standard routes using a standard survey protocol. Smart phone apps are used to navigate and record dogs along standard routes. Density expressed as dogs seen per km predicts the number of dogs residents will encounter as they commute to work or school and is therefore more meaningful than total population size. Composition in terms of gender, age and reproductive activity is measured alongside welfare, in terms of body and skin condition. The implementation of this method in seven locations reveals significant difference in roaming dog density between locations and reduction in density within one location subject to intervention. This method provides a resource efficient and reliable measure of roaming dog density, composition and welfare for the assessment of intervention impact.
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