Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study
We assessed the accuracy of scat-sampling methods in relation to sources of bias (statistical independence of the data and definition of the sampling unit) and precision (sample size). We developed a method to quantify diets of predators accurately in a study of diet selection by wolves (Canis lupus...
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ftunivtorino:oai:iris.unito.it:2318/1770120 2023-11-05T03:41:08+01:00 Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study Marucco F. Pletscher D. H. Boitani L. Marucco F. Pletscher D.H. Boitani L. 2008 http://hdl.handle.net/2318/1770120 https://doi.org/10.1644/07-MAMM-A-005R3.1 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000256553100015 volume:89 issue:3 firstpage:665 lastpage:673 numberofpages:9 journal:JOURNAL OF MAMMALOGY http://hdl.handle.net/2318/1770120 doi:10.1644/07-MAMM-A-005R3.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-45249085266 info:eu-repo/semantics/closedAccess Accuracy Canis lupu Diet selection Monte Carlo method Scat sampling Western Alp Wolf info:eu-repo/semantics/article 2008 ftunivtorino https://doi.org/10.1644/07-MAMM-A-005R3.1 2023-10-10T22:27:46Z We assessed the accuracy of scat-sampling methods in relation to sources of bias (statistical independence of the data and definition of the sampling unit) and precision (sample size). We developed a method to quantify diets of predators accurately in a study of diet selection by wolves (Canis lupus) during 3 winter seasons (1999-2002) in the Western Alps. The best sampling design to avoid pseudoreplication was the "additive method," where the presence of a carcass, estimated by either a collection of scats or a carcass itself along the travel route of a wolf, was considered 1 sampling unit. Although roe deer (Capreolus capreolus) were the primary prey used by wolves in the area, red deer (Cervus elaphus), recently reintroduced prey present at low density, were selected in winter 2001. We evaluated the optimal sample size for a given question using Monte Carlo simulations. At small sample sizes, slight increases in sample sizes caused large reductions in the standard error, greatly improving the precision of the estimates of percentage of items in the diet. Estimating the number of rare prey species used by wolves, such as red deer in our case study (<2% of the diet estimates), was possible if the minimum sample size was greater than 10-40% of the population of carcasses. We emphasized the importance of the additive method to improve the accuracy of estimates of diet selection by carnivores. © 2008 American Society of Mammalogists. Article in Journal/Newspaper Canis lupus Università degli studi di Torino: AperTo (Archivio Istituzionale ad Accesso Aperto) Journal of Mammalogy 89 3 665 673 |
institution |
Open Polar |
collection |
Università degli studi di Torino: AperTo (Archivio Istituzionale ad Accesso Aperto) |
op_collection_id |
ftunivtorino |
language |
English |
topic |
Accuracy Canis lupu Diet selection Monte Carlo method Scat sampling Western Alp Wolf |
spellingShingle |
Accuracy Canis lupu Diet selection Monte Carlo method Scat sampling Western Alp Wolf Marucco F. Pletscher D. H. Boitani L. Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
topic_facet |
Accuracy Canis lupu Diet selection Monte Carlo method Scat sampling Western Alp Wolf |
description |
We assessed the accuracy of scat-sampling methods in relation to sources of bias (statistical independence of the data and definition of the sampling unit) and precision (sample size). We developed a method to quantify diets of predators accurately in a study of diet selection by wolves (Canis lupus) during 3 winter seasons (1999-2002) in the Western Alps. The best sampling design to avoid pseudoreplication was the "additive method," where the presence of a carcass, estimated by either a collection of scats or a carcass itself along the travel route of a wolf, was considered 1 sampling unit. Although roe deer (Capreolus capreolus) were the primary prey used by wolves in the area, red deer (Cervus elaphus), recently reintroduced prey present at low density, were selected in winter 2001. We evaluated the optimal sample size for a given question using Monte Carlo simulations. At small sample sizes, slight increases in sample sizes caused large reductions in the standard error, greatly improving the precision of the estimates of percentage of items in the diet. Estimating the number of rare prey species used by wolves, such as red deer in our case study (<2% of the diet estimates), was possible if the minimum sample size was greater than 10-40% of the population of carcasses. We emphasized the importance of the additive method to improve the accuracy of estimates of diet selection by carnivores. © 2008 American Society of Mammalogists. |
author2 |
Marucco F. Pletscher D.H. Boitani L. |
format |
Article in Journal/Newspaper |
author |
Marucco F. Pletscher D. H. Boitani L. |
author_facet |
Marucco F. Pletscher D. H. Boitani L. |
author_sort |
Marucco F. |
title |
Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
title_short |
Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
title_full |
Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
title_fullStr |
Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
title_full_unstemmed |
Accuracy of scat sampling for carnivore diet analysis: Wolves in the Alps as a case study |
title_sort |
accuracy of scat sampling for carnivore diet analysis: wolves in the alps as a case study |
publishDate |
2008 |
url |
http://hdl.handle.net/2318/1770120 https://doi.org/10.1644/07-MAMM-A-005R3.1 |
genre |
Canis lupus |
genre_facet |
Canis lupus |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000256553100015 volume:89 issue:3 firstpage:665 lastpage:673 numberofpages:9 journal:JOURNAL OF MAMMALOGY http://hdl.handle.net/2318/1770120 doi:10.1644/07-MAMM-A-005R3.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-45249085266 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1644/07-MAMM-A-005R3.1 |
container_title |
Journal of Mammalogy |
container_volume |
89 |
container_issue |
3 |
container_start_page |
665 |
op_container_end_page |
673 |
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1781697439076450304 |