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Survival of Juvenile Florida Scrub-Jays is Habitat Specific, Positively Correlated With Month and Negatively Correlated With Male Breeder DeathJuvenile survival in birds is difficult to estimate but this vital rate can be an important consideration for management decisions. We estimated juvenile survival of cooperatively breeding Florida Scrub-Jays (Aphelocoma coerulescens) in a landscape degraded by fire suppression and fragmentation using data from marked (n = 325) and unmarked juveniles (n = 1,306) with an integrated hierarchical Bayesian model. To assess the combined analyses, we also analyzed these datasets separately, with a Cormack-Jolly-Seber (CJS) model (marked) and young model (unmarked). Our data consisted of monthly censuses of territorial family groups from Florida Scrub-Jay populations in East Central Florida collected over a 22-yr period. Juvenile survival was estimated from July when young Florida Scrub-Jays begin developing independence to March when they become first year individuals and grouped according to the habitat quality class of their natal territory that were based on shrub height (with intermediate shrub heights being optimal and short and tall shrub heights being suboptimal) and the presence of sandy openings (the preferred open having many sandy openings; closed not having enough). Parameter estimates in the combined analysis were intermediate to the separate analyses. Notable differences among the separate analyses were that suboptimal habitat survival was lower in the unmarked analysis, the unmarked analysis showed a linear effect of time not seen in the marked analysis, and there was an effect of male breeder death in the marked but not unmarked analysis. The combined data analysis provided more inference than did either data set analyzed separately including juveniles in optimal-closed territories unexpectedly had higher survival than those in optimal-open, survival increased through time, and male breeder death had a negative effect on survival. This study suggests that optimal-closed habitat may play an important role in juvenile Florida Scrub-Jay survival perhaps by providing better cover from predators and warrants further investigation for management implications.
Document ID
20220005469
Acquisition Source
Kennedy Space Center
Document Type
Accepted Manuscript (Version with final changes)
Authors
Geoffrey M Carter ORCID
(Herndon Solutions Group Henderson, Nevada, United States)
Eric D Stolen
(Herndon Solutions Group Henderson, Nevada, United States)
David R Breininger
(Herndon Solutions Group Henderson, Nevada, United States)
Stephanie A Legare
(Herndon Solutions Group Henderson, Nevada, United States)
Danny K Hunt
(Herndon Solutions Group Henderson, Nevada, United States)
Christopher D Schumann
(Herndon Solutions Group Henderson, Nevada, United States)
William V Payne
(Herndon Solutions Group Henderson, Nevada, United States)
Date Acquired
April 7, 2022
Publication Date
July 25, 2023
Publication Information
Publication: Ornithological Applications
Publisher: Oxford University Press (United Kingdom)
Volume: 125
Issue: 4
Issue Publication Date: November 6, 2023
ISSN: 0010-5422
e-ISSN: 2732-4621
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: 80KSC020D0023
Distribution Limits
Public
Copyright
Public Use Permitted.
Technical Review
Professional Review
Keywords
Florida Scrub-Jay
independent juvenile survival
hierarchical Bayesian model
habitat specific survival
Aphelocoma coerulescens
Cooperative breeder
Integrated model
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