Consistent apparent adult survival and nest-site fidelity of Whimbrel (Numenius phaeopus) near Churchill, Manitoba, Canada over a 40-year period
- 1. Trent University
- 2. Cornell University
- 3. University of Massachusetts Amherst
- 4. Independent*
Description
Reliable estimates of adult survival for many shorebird species are lacking. We used Cormack-Jolly-Seber (CJS) methods to provide an estimate of apparent, or local, survival (φ) of a population of Whimbrels, Numenius phaeopus, breeding in the subarctic Churchill, Manitoba region. We used data collected in two time periods: 1973–1976 and 2010–2014. We also quantified nest-site fidelity in 2010–2014 to provide context to our apparent survival estimates because mark-recapture analyses cannot distinguish between mortality and permanent emigration. The most parsimonious CJS model did not include effects of sex or time on apparent adult survival in either period (φ = 0.76 ± 0.13 SE; φ = 0.75 ± 0.04 SE, 1973 – 1976 and 2010 – 2014, respectively). Additionally, observations of marked Whimbrels between 2010 and 2019 (n = 124) showed that 61 of the 105 marked individuals (58.1%) were resighted. These estimates of return rates are, as expected, much lower than estimates of apparent survival. The median year-to-year distance between nests (n = 139) from 2010 to 2014 was 198 ± 88 m SE and did not differ significantly (p = 0.84) between females (x ̅ = 721.9 ± 119.8 m SE) and males (x ̅ = 720.3 ± 83.1 m SE). If our apparent survival estimate is indicative of true survivorship, then adult mortality during the nonbreeding season has remained constant over the last five decades, implying that the recent decline in Whimbrel populations may stem largely from reduced fecundity, including egg or juvenile survival, rather than primarily from reduced adult survival.
Notes
Funding provided by: Environment and Climate Change Canada
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100008638
Award Number: GCXE22C330
Funding provided by: Churchill Northern Studies Centre
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100002877
Award Number:
Funding provided by: Trent University
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100000184
Award Number:
Funding provided by: Arctic Audubon Society*
Crossref Funder Registry ID:
Award Number:
Funding provided by: Canadian Polar Commission*
Crossref Funder Registry ID:
Award Number:
Funding provided by: American Museum of Natural History
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100005835
Award Number:
Funding provided by: National Science Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000001
Award Number: 1110444
Funding provided by: Ontario Graduate Scholarship*
Crossref Funder Registry ID:
Award Number:
Funding provided by: Manomet Center for Conservation Sciences*
Crossref Funder Registry ID:
Award Number:
Funding provided by: Faucett Family Foundation*
Crossref Funder Registry ID:
Award Number:
Funding provided by: David and Lucile Packard Foundation
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000008
Award Number:
Funding provided by: Institute for Wetland and Waterfowl Research, Ducks Unlimited Canada
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100005266
Award Number:
Funding provided by: Cornell University
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100007231
Award Number:
Funding provided by: U.S. Fish and Wildlife Service
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000202
Award Number: 4074
Funding provided by: U.S. Fish and Wildlife Service
Crossref Funder Registry ID: http://dx.doi.org/10.13039/100000202
Award Number: 5147
Funding provided by: Natural Sciences and Engineering Research Council of Canada
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100000038
Award Number: RGPIN-2017-04449
Funding provided by: National Research Council Canada
Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100000046
Award Number: A3472