Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models
Abstract The Dusky Canada Goose (Branta canadensis occidentalis) population that breeds in the Copper River Delta, Alaska, has declined substantially since the late 1970s. Persistent low numbers have been attributed to low productivity in recent years. We examined patterns in survival rates of 1,852...
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Online Access: | http://dx.doi.org/10.1093/auk/123.1.198 http://academic.oup.com/auk/article-pdf/123/1/198/29690734/auk0198.pdf |
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croxfordunivpr:10.1093/auk/123.1.198 2024-09-15T18:00:19+00:00 Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models Grand, James B. Fondell, Thomas F. Miller, David A. Anthony, R. Michael Burger, A. E. 2006 http://dx.doi.org/10.1093/auk/123.1.198 http://academic.oup.com/auk/article-pdf/123/1/198/29690734/auk0198.pdf en eng Oxford University Press (OUP) The Auk volume 123, issue 1, page 198-210 ISSN 1938-4254 0004-8038 journal-article 2006 croxfordunivpr https://doi.org/10.1093/auk/123.1.198 2024-07-29T04:20:47Z Abstract The Dusky Canada Goose (Branta canadensis occidentalis) population that breeds in the Copper River Delta, Alaska, has declined substantially since the late 1970s. Persistent low numbers have been attributed to low productivity in recent years. We examined patterns in survival rates of 1,852 nests to better understand ecological processes that influenced productivity during 1997-2000. We compared 10 nonparametric models of daily survival rate of nests (DSR) that included variation among years, calendar dates, nest initiation dates, and nest ages with equivalent models based on parametric functions. The unequivocal best model included patterns of DSR that varied among discrete periods of years, calendar dates, and nest ages. Generally, DSR was low early in the nesting season and higher midseason. Across years, patterns in DSR were most variable early and late in the nesting season. Daily survival rates of nests declined between the first and second week after initiation, increased until the fourth week, and then declined during the last week before hatch. Nest survival probability estimates ranged from 0.07 to 0.71 across years and nest initiation dates. Mean rates of nest survival ranged between 0.21 and 0.31 each year. We suggest (1) considering models that do not limit estimates of daily nest survival to parametric forms; (2) placing greater emphasis on sample size when nests are rare, to obtain accurate estimates of nest survival; and (3) developing new techniques to estimate the number of nests initiated. Supervivencia de los Nidos en Branta canadensis occidentalis: Uso de Modelos de Tiempo Discreto Article in Journal/Newspaper Branta canadensis Canada Goose Alaska Oxford University Press The Auk 123 1 198 210 |
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Open Polar |
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Oxford University Press |
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croxfordunivpr |
language |
English |
description |
Abstract The Dusky Canada Goose (Branta canadensis occidentalis) population that breeds in the Copper River Delta, Alaska, has declined substantially since the late 1970s. Persistent low numbers have been attributed to low productivity in recent years. We examined patterns in survival rates of 1,852 nests to better understand ecological processes that influenced productivity during 1997-2000. We compared 10 nonparametric models of daily survival rate of nests (DSR) that included variation among years, calendar dates, nest initiation dates, and nest ages with equivalent models based on parametric functions. The unequivocal best model included patterns of DSR that varied among discrete periods of years, calendar dates, and nest ages. Generally, DSR was low early in the nesting season and higher midseason. Across years, patterns in DSR were most variable early and late in the nesting season. Daily survival rates of nests declined between the first and second week after initiation, increased until the fourth week, and then declined during the last week before hatch. Nest survival probability estimates ranged from 0.07 to 0.71 across years and nest initiation dates. Mean rates of nest survival ranged between 0.21 and 0.31 each year. We suggest (1) considering models that do not limit estimates of daily nest survival to parametric forms; (2) placing greater emphasis on sample size when nests are rare, to obtain accurate estimates of nest survival; and (3) developing new techniques to estimate the number of nests initiated. Supervivencia de los Nidos en Branta canadensis occidentalis: Uso de Modelos de Tiempo Discreto |
author2 |
Burger, A. E. |
format |
Article in Journal/Newspaper |
author |
Grand, James B. Fondell, Thomas F. Miller, David A. Anthony, R. Michael |
spellingShingle |
Grand, James B. Fondell, Thomas F. Miller, David A. Anthony, R. Michael Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
author_facet |
Grand, James B. Fondell, Thomas F. Miller, David A. Anthony, R. Michael |
author_sort |
Grand, James B. |
title |
Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
title_short |
Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
title_full |
Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
title_fullStr |
Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
title_full_unstemmed |
Nest Survival in Dusky Canada Geese (Branta Canadensis Occidentalis): Use of Discrete-Time Models |
title_sort |
nest survival in dusky canada geese (branta canadensis occidentalis): use of discrete-time models |
publisher |
Oxford University Press (OUP) |
publishDate |
2006 |
url |
http://dx.doi.org/10.1093/auk/123.1.198 http://academic.oup.com/auk/article-pdf/123/1/198/29690734/auk0198.pdf |
genre |
Branta canadensis Canada Goose Alaska |
genre_facet |
Branta canadensis Canada Goose Alaska |
op_source |
The Auk volume 123, issue 1, page 198-210 ISSN 1938-4254 0004-8038 |
op_doi |
https://doi.org/10.1093/auk/123.1.198 |
container_title |
The Auk |
container_volume |
123 |
container_issue |
1 |
container_start_page |
198 |
op_container_end_page |
210 |
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1810437497485787136 |