Estimating wolf (Canis lupus) population size from number of packs and an individual based model
Estimating wildlife population size is fundamental for wildlife management and conservation. However, making monitoring of population size less resource demanding while still keeping a high monitoring accuracy and precision remains a recurrent challenge. One proposed alternative to count individuals...
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ftrepec:oai:RePEc:eee:ecomod:v:339:y:2016:i:c:p:33-44 2024-04-14T08:10:08+00:00 Estimating wolf (Canis lupus) population size from number of packs and an individual based model Chapron, Guillaume Wikenros, Camilla Liberg, Olof Wabakken, Petter Flagstad, Øystein Milleret, Cyril Månsson, Johan Svensson, Linn Zimmermann, Barbara Åkesson, Mikael Sand, Håkan http://www.sciencedirect.com/science/article/pii/S0304380016303179 unknown http://www.sciencedirect.com/science/article/pii/S0304380016303179 article ftrepec 2024-03-19T10:34:27Z Estimating wildlife population size is fundamental for wildlife management and conservation. However, making monitoring of population size less resource demanding while still keeping a high monitoring accuracy and precision remains a recurrent challenge. One proposed alternative to count individuals is to instead focus on counting a segment of the population that is easier to monitor but at the same time well informative on total population size. We show how total population size can be estimated from group counts by using an individual-based population model in a social living species. We developed a wolf (Canis lupus) specific Individual Based Model and used Approximate Bayesian Computation (ABC) to fit this population model to the time series of annual number of packs, reproductions and pairs obtained from Scandinavian monitoring data. Model informative priors were obtained with data from collared individuals by the Scandinavian wolf research project. The fitted model was then used to estimate a conversion factor from number of packs to total number of individuals and to number of reproductions. There was a good fit between the retained simulations by ABC and the observed Scandinavian wolf population trajectory. The fitted simulations returned a conversion factor of 8.0 (95% CI=6.62–10.07) from number of packs to total population size and of 1.0 (95% CI=0.93–1.12) to number of reproductions in December. A sensitivity analysis revealed that the conversion factor from packs to total population size was positively correlated with pup survival and litter size and negatively correlated with subadult, vagrant and adult survivals. Using an individual based model allowed us to model the full complexity of demographic traits of a social-living species such as the wolf. The flexibility of the model also meant that the conversion factor could be estimated for any month during the year. Our approach to estimate total population size from counts of groups requires having a population model where both individuals and ... Article in Journal/Newspaper Canis lupus RePEc (Research Papers in Economics) |
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RePEc (Research Papers in Economics) |
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description |
Estimating wildlife population size is fundamental for wildlife management and conservation. However, making monitoring of population size less resource demanding while still keeping a high monitoring accuracy and precision remains a recurrent challenge. One proposed alternative to count individuals is to instead focus on counting a segment of the population that is easier to monitor but at the same time well informative on total population size. We show how total population size can be estimated from group counts by using an individual-based population model in a social living species. We developed a wolf (Canis lupus) specific Individual Based Model and used Approximate Bayesian Computation (ABC) to fit this population model to the time series of annual number of packs, reproductions and pairs obtained from Scandinavian monitoring data. Model informative priors were obtained with data from collared individuals by the Scandinavian wolf research project. The fitted model was then used to estimate a conversion factor from number of packs to total number of individuals and to number of reproductions. There was a good fit between the retained simulations by ABC and the observed Scandinavian wolf population trajectory. The fitted simulations returned a conversion factor of 8.0 (95% CI=6.62–10.07) from number of packs to total population size and of 1.0 (95% CI=0.93–1.12) to number of reproductions in December. A sensitivity analysis revealed that the conversion factor from packs to total population size was positively correlated with pup survival and litter size and negatively correlated with subadult, vagrant and adult survivals. Using an individual based model allowed us to model the full complexity of demographic traits of a social-living species such as the wolf. The flexibility of the model also meant that the conversion factor could be estimated for any month during the year. Our approach to estimate total population size from counts of groups requires having a population model where both individuals and ... |
format |
Article in Journal/Newspaper |
author |
Chapron, Guillaume Wikenros, Camilla Liberg, Olof Wabakken, Petter Flagstad, Øystein Milleret, Cyril Månsson, Johan Svensson, Linn Zimmermann, Barbara Åkesson, Mikael Sand, Håkan |
spellingShingle |
Chapron, Guillaume Wikenros, Camilla Liberg, Olof Wabakken, Petter Flagstad, Øystein Milleret, Cyril Månsson, Johan Svensson, Linn Zimmermann, Barbara Åkesson, Mikael Sand, Håkan Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
author_facet |
Chapron, Guillaume Wikenros, Camilla Liberg, Olof Wabakken, Petter Flagstad, Øystein Milleret, Cyril Månsson, Johan Svensson, Linn Zimmermann, Barbara Åkesson, Mikael Sand, Håkan |
author_sort |
Chapron, Guillaume |
title |
Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
title_short |
Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
title_full |
Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
title_fullStr |
Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
title_full_unstemmed |
Estimating wolf (Canis lupus) population size from number of packs and an individual based model |
title_sort |
estimating wolf (canis lupus) population size from number of packs and an individual based model |
url |
http://www.sciencedirect.com/science/article/pii/S0304380016303179 |
genre |
Canis lupus |
genre_facet |
Canis lupus |
op_relation |
http://www.sciencedirect.com/science/article/pii/S0304380016303179 |
_version_ |
1796307643269120000 |