Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation
We estimated the current size and dynamics of the wolf population in Tuscany and investigated the trends and demographic drivers of population changes. Estimates were obtained by two different approaches: (i) mixed-technique field monitoring (from 2014 to 2016) that found the minimum observed pack n...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-05-01
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| Series: | Animals |
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| Online Access: | https://www.mdpi.com/2076-2615/13/11/1735 |
| _version_ | 1797598006929784832 |
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| author | Enrico Merli Luca Mattioli Elena Bassi Paolo Bongi Duccio Berzi Francesca Ciuti Siriano Luccarini Federico Morimando Viviana Viviani Romolo Caniglia Marco Galaverni Elena Fabbri Massimo Scandura Marco Apollonio |
| author_facet | Enrico Merli Luca Mattioli Elena Bassi Paolo Bongi Duccio Berzi Francesca Ciuti Siriano Luccarini Federico Morimando Viviana Viviani Romolo Caniglia Marco Galaverni Elena Fabbri Massimo Scandura Marco Apollonio |
| author_sort | Enrico Merli |
| collection | DOAJ |
| description | We estimated the current size and dynamics of the wolf population in Tuscany and investigated the trends and demographic drivers of population changes. Estimates were obtained by two different approaches: (i) mixed-technique field monitoring (from 2014 to 2016) that found the minimum observed pack number and estimated population size, and (ii) an individual-based model (run by Vortex software v. 10.3.8.0) with demographic inputs derived from a local intensive study area and historic data on population size. Field monitoring showed a minimum population size of 558 wolves (SE = 12.005) in 2016, with a density of 2.74 individuals/100 km<sup>2</sup>. The population model described an increasing trend with an average annual rate of increase λ = 1.075 (SE = 0.014), an estimated population size of about 882 individuals (SE = 9.397) in 2016, and a density of 4.29 wolves/100 km<sup>2</sup>. Previously published estimates of wolf population were as low as 56.2% compared to our field monitoring estimation and 34.6% in comparison to our model estimation. We conducted sensitivity tests to analyze the key parameters driving population changes based on juvenile and adult mortality rates, female breeding success, and litter size. Mortality rates played a major role in determining intrinsic growth rate changes, with adult mortality accounting for 62.5% of the total variance explained by the four parameters. Juvenile mortality was responsible for 35.8% of the variance, while female breeding success and litter size had weak or negligible effects. We concluded that reliable estimates of population abundance and a deeper understanding of the role of different demographic parameters in determining population dynamics are crucial to define and carry out appropriate conservation and management strategies to address human–wildlife conflicts. |
| first_indexed | 2024-03-11T03:12:18Z |
| format | Article |
| id | doaj.art-45645289f133452c9b9704044a95d33b |
| institution | Directory Open Access Journal |
| issn | 2076-2615 |
| language | English |
| last_indexed | 2024-03-11T03:12:18Z |
| publishDate | 2023-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Animals |
| spelling | doaj.art-45645289f133452c9b9704044a95d33b2023-11-18T07:29:02ZengMDPI AGAnimals2076-26152023-05-011311173510.3390/ani13111735Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and ConservationEnrico Merli0Luca Mattioli1Elena Bassi2Paolo Bongi3Duccio Berzi4Francesca Ciuti5Siriano Luccarini6Federico Morimando7Viviana Viviani8Romolo Caniglia9Marco Galaverni10Elena Fabbri11Massimo Scandura12Marco Apollonio13Department of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyWildlife Service, Tuscany Region, 50127 Florence, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyUnit for Conservation Genetics (BIO-CGE), Italian Institute for Environmental Protection and Research (ISPRA), 40064 Bologna, ItalyScience Unit, WWF Italia, 00198 Rome, ItalyUnit for Conservation Genetics (BIO-CGE), Italian Institute for Environmental Protection and Research (ISPRA), 40064 Bologna, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyDepartment of Veterinary Medicine, University of Sassari, 07100 Sassari, ItalyWe estimated the current size and dynamics of the wolf population in Tuscany and investigated the trends and demographic drivers of population changes. Estimates were obtained by two different approaches: (i) mixed-technique field monitoring (from 2014 to 2016) that found the minimum observed pack number and estimated population size, and (ii) an individual-based model (run by Vortex software v. 10.3.8.0) with demographic inputs derived from a local intensive study area and historic data on population size. Field monitoring showed a minimum population size of 558 wolves (SE = 12.005) in 2016, with a density of 2.74 individuals/100 km<sup>2</sup>. The population model described an increasing trend with an average annual rate of increase λ = 1.075 (SE = 0.014), an estimated population size of about 882 individuals (SE = 9.397) in 2016, and a density of 4.29 wolves/100 km<sup>2</sup>. Previously published estimates of wolf population were as low as 56.2% compared to our field monitoring estimation and 34.6% in comparison to our model estimation. We conducted sensitivity tests to analyze the key parameters driving population changes based on juvenile and adult mortality rates, female breeding success, and litter size. Mortality rates played a major role in determining intrinsic growth rate changes, with adult mortality accounting for 62.5% of the total variance explained by the four parameters. Juvenile mortality was responsible for 35.8% of the variance, while female breeding success and litter size had weak or negligible effects. We concluded that reliable estimates of population abundance and a deeper understanding of the role of different demographic parameters in determining population dynamics are crucial to define and carry out appropriate conservation and management strategies to address human–wildlife conflicts.https://www.mdpi.com/2076-2615/13/11/1735wolfpopulation sizepopulation dynamicsdemographic driversVortex |
| spellingShingle | Enrico Merli Luca Mattioli Elena Bassi Paolo Bongi Duccio Berzi Francesca Ciuti Siriano Luccarini Federico Morimando Viviana Viviani Romolo Caniglia Marco Galaverni Elena Fabbri Massimo Scandura Marco Apollonio Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation Animals wolf population size population dynamics demographic drivers Vortex |
| title | Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation |
| title_full | Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation |
| title_fullStr | Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation |
| title_full_unstemmed | Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation |
| title_short | Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation |
| title_sort | estimating wolf population size and dynamics by field monitoring and demographic models implications for management and conservation |
| topic | wolf population size population dynamics demographic drivers Vortex |
| url | https://www.mdpi.com/2076-2615/13/11/1735 |
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