Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification
Children's Pool Beach in La Jolla, CA is a Pacific harbor seal (Phoca vitulina richardsi) rookery at the center of a large legal controversy. Due to the heated contention surrounding this rookery, very few scientific studies have been done on the population of harbor seals that use this haul-ou...
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2011
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ftcdlib:qt9n87h01f 2023-05-15T16:33:10+02:00 Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification Linder, Traci A. 1 PDF (1 online resource xi, 36 p.) 2011-01-01 application/pdf http://www.escholarship.org/uc/item/9n87h01f http://n2t.net/ark:/20775/bb9045704c unknown eScholarship, University of California http://www.escholarship.org/uc/item/9n87h01f qt9n87h01f http://n2t.net/ark:/20775/bb9045704c public Linder, Traci A.(2011). Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/9n87h01f UCSD Dissertations Academic Biology. (Discipline) Dissertations Academic as Topic dissertation 2011 ftcdlib 2016-04-02T18:54:15Z Children's Pool Beach in La Jolla, CA is a Pacific harbor seal (Phoca vitulina richardsi) rookery at the center of a large legal controversy. Due to the heated contention surrounding this rookery, very few scientific studies have been done on the population of harbor seals that use this haul-out site. Maximum daily haul-out counts rarely exceed 200, and management decisions have been framed around the assumption of a largely resident population of no more than approximately 250 seals. In this study I used photo- identification and mark-recapture methods to estimate the total population of Pacific harbor seals that used Children's Pool Beach as a haul-out site during January - October 2008. I photographed the ventral surfaces of adult harbor seals at Children's Pool Beach, and then entered each good to high quality photograph into an interactive computer-assisted photograph-matching system for individual identification. Each individual identification was confirmed by both a trained volunteer and myself, resulting in a 4% visual matching error rate. After analysis concluded, 480 unique adult harbor seals were individually identified after applying the 4% visual matching error rate. Abundance estimation was calculated using the Chapman-Petersen capture-recapture model. My calculations yielded a population estimate of 596 individuals during January - October 2008, which is two to three times larger than previously believed. These findings suggest a population that is at least partially open with considerable coastal movement, suggesting that Children's Pool Beach is potentially part of a regional network of interconnected haul-out site Doctoral or Postdoctoral Thesis harbor seal Phoca vitulina University of California: eScholarship Pacific Petersen ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
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University of California: eScholarship |
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unknown |
topic |
UCSD Dissertations Academic Biology. (Discipline) Dissertations Academic as Topic |
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UCSD Dissertations Academic Biology. (Discipline) Dissertations Academic as Topic Linder, Traci A. Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
topic_facet |
UCSD Dissertations Academic Biology. (Discipline) Dissertations Academic as Topic |
description |
Children's Pool Beach in La Jolla, CA is a Pacific harbor seal (Phoca vitulina richardsi) rookery at the center of a large legal controversy. Due to the heated contention surrounding this rookery, very few scientific studies have been done on the population of harbor seals that use this haul-out site. Maximum daily haul-out counts rarely exceed 200, and management decisions have been framed around the assumption of a largely resident population of no more than approximately 250 seals. In this study I used photo- identification and mark-recapture methods to estimate the total population of Pacific harbor seals that used Children's Pool Beach as a haul-out site during January - October 2008. I photographed the ventral surfaces of adult harbor seals at Children's Pool Beach, and then entered each good to high quality photograph into an interactive computer-assisted photograph-matching system for individual identification. Each individual identification was confirmed by both a trained volunteer and myself, resulting in a 4% visual matching error rate. After analysis concluded, 480 unique adult harbor seals were individually identified after applying the 4% visual matching error rate. Abundance estimation was calculated using the Chapman-Petersen capture-recapture model. My calculations yielded a population estimate of 596 individuals during January - October 2008, which is two to three times larger than previously believed. These findings suggest a population that is at least partially open with considerable coastal movement, suggesting that Children's Pool Beach is potentially part of a regional network of interconnected haul-out site |
format |
Doctoral or Postdoctoral Thesis |
author |
Linder, Traci A. |
author_facet |
Linder, Traci A. |
author_sort |
Linder, Traci A. |
title |
Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
title_short |
Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
title_full |
Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
title_fullStr |
Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
title_full_unstemmed |
Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification |
title_sort |
estimating population size of pacific harbor seals (phoca vitulina richardsi) at children's pool beach in la jolla, california, using photo-identification |
publisher |
eScholarship, University of California |
publishDate |
2011 |
url |
http://www.escholarship.org/uc/item/9n87h01f http://n2t.net/ark:/20775/bb9045704c |
op_coverage |
1 PDF (1 online resource xi, 36 p.) |
long_lat |
ENVELOPE(-101.250,-101.250,-71.917,-71.917) |
geographic |
Pacific Petersen |
geographic_facet |
Pacific Petersen |
genre |
harbor seal Phoca vitulina |
genre_facet |
harbor seal Phoca vitulina |
op_source |
Linder, Traci A.(2011). Estimating population size of Pacific harbor seals (Phoca vitulina richardsi) at Children's Pool Beach in La Jolla, California, using photo-identification. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/9n87h01f |
op_relation |
http://www.escholarship.org/uc/item/9n87h01f qt9n87h01f http://n2t.net/ark:/20775/bb9045704c |
op_rights |
public |
_version_ |
1766022879181275136 |