dc.contributor.author |
Oosthuizen, Wessel Christiaan
|
|
dc.contributor.author |
De Bruyn, P.J. Nico
|
|
dc.contributor.author |
Bester, Marthan Nieuwoudt
|
|
dc.contributor.author |
Girondot, Marc
|
|
dc.date.accessioned |
2011-02-23T08:51:15Z |
|
dc.date.available |
2011-02-23T08:51:15Z |
|
dc.date.issued |
2010-04 |
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dc.description.abstract |
Marker-loss is a common feature of mark–recapture studies and important as
it may bias parameter estimation. A slight alteration in tag-site of double tagged
southern elephant seals (Mirounga leonina), marked at Marion Island from 1983 to
2005 in an ongoing mark–recapture program, had important consequences for tagloss.
We calculated age-specific tag-retention rates and cumulative tag-retention
probabilities using a maximum likelihood model selection approach in the software
application TAG LOSS 3.2.0. Under the tag-loss independence assumption, double
tag-loss of inner interdigital webbing tags (IIT; 17 cohorts) remained below 1%
in the first 5 yr and increased monotonically as seals aged, with higher tag-loss
in males. Lifetime cumulative IIT tag-loss was 11.9% for females and 18.4% for
males, and equivalent for all cohorts. Changing the tag-site to the outer interdigital
webbing (OIT; 6 cohorts) resulted in increased and cohort-dependent tag-loss,
although the variation (mean ± 95% CI) in cumulative tag-loss probabilities never
exceeded 5.3% between cohorts at similar age. Although different studies may
homogenize techniques, we advocate the importance of data set-specific assessment
of tag-loss rates to ensure greatest confidence in population parameters obtained
from mark–recapture experiments. Permanent marking should be implemented
where feasible. |
en |
dc.description.sponsorship |
The Department of Science and Technology, through the National Research Foundation (NRF), provided financial support. WCO received financial support from a NRF Grantholder-linked bursary within the project “Conservation of Seabirds, Shorebirds and Seals” led by L. Underhill of the Animal Demography Unit, Department of Zoology, University of Cape Town |
en |
dc.identifier.citation |
Oosthuizen, WC, De Bruyn, PJN, Bester, MN & Girandot, N 2010, 'Cohort and tag-site-specific tag-loss rates in mark–recapture studies : a southern elephant seal cautionary case', Marine Mammal Science, vol. 26, no.2, pp. 225-236. [http://www3.interscience.wiley.com/journal/118534279/home] |
en |
dc.identifier.issn |
0824-0469 |
|
dc.identifier.other |
10.1111/j.1748-7692.2009.00328.x |
|
dc.identifier.uri |
http://hdl.handle.net/2263/15930 |
|
dc.language.iso |
en |
en |
dc.publisher |
Wiley -Blackwell |
en |
dc.rights |
© 2009 by the Society for Marine Mammalogy. The definite version is available at www.blackwell-synergy.com. |
en |
dc.subject |
Mirounga leonina |
en |
dc.subject |
Mark–resight |
en |
dc.subject |
Cohort heterogeneity |
en |
dc.subject |
Double tagging |
en |
dc.subject |
Marker-loss |
en |
dc.subject |
Marion Island |
en |
dc.subject |
Phocids |
en |
dc.subject |
Tag shedding |
en |
dc.subject |
Tag placement |
en |
dc.subject.lcsh |
Southern elephant seal -- Marking |
en |
dc.subject.lcsh |
Animal marking |
en |
dc.title |
Cohort and tag-site specific tag-loss rates in mark-recapture studies : a southern elephant seal cautionary case |
en |
dc.type |
Postprint Article |
en |