Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata )
Information from the classification of age-specific developmental stages has been used to adjust aerial survey estimates of pup production in a number of species of seals, including the hooded seal (Cystophora cristata). We test the assumption that hooded seal pups were accurately and consistently c...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Language: | English |
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Canadian Science Publishing
1988
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Online Access: | http://dx.doi.org/10.1139/f88-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f88-086 |
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crcansciencepubl:10.1139/f88-086 2023-12-17T10:29:20+01:00 Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) Stenson, G. B. Myers, R. A. 1988 http://dx.doi.org/10.1139/f88-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f88-086 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Fisheries and Aquatic Sciences volume 45, issue 4, page 715-719 ISSN 0706-652X 1205-7533 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 1988 crcansciencepubl https://doi.org/10.1139/f88-086 2023-11-19T13:39:07Z Information from the classification of age-specific developmental stages has been used to adjust aerial survey estimates of pup production in a number of species of seals, including the hooded seal (Cystophora cristata). We test the assumption that hooded seal pups were accurately and consistently classified according to developmental stage and examine the consequences of misclassifications upon adjusted population estimates. We determined overall misclassification rates, the effect of survey height on classifications, and interobserver variability. At ice level, misclassifications rates were low (<3%). From an altitude of 30 m, newborn pups could not be classified correctly and misclassification rates for the two other stages of attended pups varied between 6.4 and 21.3%. There was no evidence of an overall bias in classifications or differences among observers although there was a significant interaction between day and stage. Individual pups appear to have been misclassified independently by each observer. Under actual survey conditions, observers classified a similar proportion of pups into each recognizable stage. The misclassification rates we observed did not significantly alter the previous population estimate. Methods for improving the current survey design include modifying classification criteria, providing observers with a period of on-ice training, and reducing the width of survey transects. Article in Journal/Newspaper Cystophora cristata hooded seal Canadian Science Publishing (via Crossref) Canadian Journal of Fisheries and Aquatic Sciences 45 4 715 719 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics Stenson, G. B. Myers, R. A. Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
Information from the classification of age-specific developmental stages has been used to adjust aerial survey estimates of pup production in a number of species of seals, including the hooded seal (Cystophora cristata). We test the assumption that hooded seal pups were accurately and consistently classified according to developmental stage and examine the consequences of misclassifications upon adjusted population estimates. We determined overall misclassification rates, the effect of survey height on classifications, and interobserver variability. At ice level, misclassifications rates were low (<3%). From an altitude of 30 m, newborn pups could not be classified correctly and misclassification rates for the two other stages of attended pups varied between 6.4 and 21.3%. There was no evidence of an overall bias in classifications or differences among observers although there was a significant interaction between day and stage. Individual pups appear to have been misclassified independently by each observer. Under actual survey conditions, observers classified a similar proportion of pups into each recognizable stage. The misclassification rates we observed did not significantly alter the previous population estimate. Methods for improving the current survey design include modifying classification criteria, providing observers with a period of on-ice training, and reducing the width of survey transects. |
format |
Article in Journal/Newspaper |
author |
Stenson, G. B. Myers, R. A. |
author_facet |
Stenson, G. B. Myers, R. A. |
author_sort |
Stenson, G. B. |
title |
Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
title_short |
Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
title_full |
Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
title_fullStr |
Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
title_full_unstemmed |
Accuracy of Pup Classifications and Its Effect on Population Estimates in the Hooded Seal ( Cystophora cristata ) |
title_sort |
accuracy of pup classifications and its effect on population estimates in the hooded seal ( cystophora cristata ) |
publisher |
Canadian Science Publishing |
publishDate |
1988 |
url |
http://dx.doi.org/10.1139/f88-086 http://www.nrcresearchpress.com/doi/pdf/10.1139/f88-086 |
genre |
Cystophora cristata hooded seal |
genre_facet |
Cystophora cristata hooded seal |
op_source |
Canadian Journal of Fisheries and Aquatic Sciences volume 45, issue 4, page 715-719 ISSN 0706-652X 1205-7533 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/f88-086 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
45 |
container_issue |
4 |
container_start_page |
715 |
op_container_end_page |
719 |
_version_ |
1785581685956411392 |