Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns

Jansen, Dorine Y.M.; Abadi, Fitsum; Harebottle, Doug; Altwegg, Res

Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns

dc.contributor	Dr R.A. Navarro	en_ZA
dc.contributor	Bird ringers and SAFRING	en_ZA
dc.contributor.author	Jansen, Dorine Y.M.
dc.contributor.author	Abadi, Fitsum
dc.contributor.author	Harebottle, Doug
dc.contributor.author	Altwegg, Res
dc.coverage.spatial	southern Africa	en_ZA
dc.coverage.spatial	Global patterns	en_ZA
dc.date.accessioned	2014-06-19T09:24:57Z
dc.date.available	2014-06-19T09:24:57Z
dc.date.issued	2014
dc.description.abstract	Among birds, northern temperate species generally have larger clutches, shorter development periods and lower adult survival than similarly-sized southern and tropical species. Even though this global pattern is well accepted, the driving mechanism is still not fully understood. The main theories are founded on the differing environmental seasonality of these zones (higher seasonality in the North). These patterns arise in cross-species comparisons, but we hypothesized that the same patterns should arise among populations within a species if different types of seasonality select for different life histories. Few studies have examined this. We estimated survival of an azonal habitat specialist, the African reed warbler, across the environmentally diverse African subcontinent, and related survival to latitude and to the seasonality of the different environments of their breeding habitats. Data (1998–2010) collected through a public ringing scheme were analyzed with hierarchical capture-mark-recapture models to determine resident adult survival and its spatial variance across sixteen vegetation units spread across four biomes. The models were defined as state-space multi-state models to account for transience and implemented in a Bayesian framework. We did not find a latitudinal trend in survival or a clear link between seasonality and survival. Spatial variation in survival was substantial across the sixteen sites (spatial standard deviation of the logit mean survival: 0.70, 95% credible interval (CRI): 0.33–1.27). Mean site survival ranged from 0.49 (95% CRI: 0.18–0.80) to 0.83 (95% CRI: 0.62–0.97) with an overall mean of 0.67 (95% CRI: 0.47–0.85). A hierarchical modeling approach enabled us to estimate spatial variation in survival of the African reed warbler across the African subcontinent from sparse data. Although we could not confirm the global pattern of higher survival in less seasonal environments, our findings from a poorly studied region contribute to the study of life-history strategies.	en_ZA
dc.identifier.apacitation	Jansen, Dorine Y. M., Abadi, F., Harebottle, D., & Altwegg, R. (2014). Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns. <i>Ecology and Evolution</i>, http://hdl.handle.net/11427/1010	en_ZA
dc.identifier.chicagocitation	Jansen, Dorine Y.M., Fitsum Abadi, Doug Harebottle, and Res Altwegg "Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns." <i>Ecology and Evolution</i> (2014) http://hdl.handle.net/11427/1010	en_ZA
dc.identifier.citation	Jansen DYM, Abadi F, Harebottle D, Altwegg R. 2014. Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns. Ecology and Evolution 4(7): 889–898. doi: 10.1002/ece3.958	en_ZA
dc.identifier.ris	TY - Journal Article AU - Jansen, Dorine Y.M. AU - Abadi, Fitsum AU - Harebottle, Doug AU - Altwegg, Res AB - Among birds, northern temperate species generally have larger clutches, shorter development periods and lower adult survival than similarly-sized southern and tropical species. Even though this global pattern is well accepted, the driving mechanism is still not fully understood. The main theories are founded on the differing environmental seasonality of these zones (higher seasonality in the North). These patterns arise in cross-species comparisons, but we hypothesized that the same patterns should arise among populations within a species if different types of seasonality select for different life histories. Few studies have examined this. We estimated survival of an azonal habitat specialist, the African reed warbler, across the environmentally diverse African subcontinent, and related survival to latitude and to the seasonality of the different environments of their breeding habitats. Data (1998–2010) collected through a public ringing scheme were analyzed with hierarchical capture-mark-recapture models to determine resident adult survival and its spatial variance across sixteen vegetation units spread across four biomes. The models were defined as state-space multi-state models to account for transience and implemented in a Bayesian framework. We did not find a latitudinal trend in survival or a clear link between seasonality and survival. Spatial variation in survival was substantial across the sixteen sites (spatial standard deviation of the logit mean survival: 0.70, 95% credible interval (CRI): 0.33–1.27). Mean site survival ranged from 0.49 (95% CRI: 0.18–0.80) to 0.83 (95% CRI: 0.62–0.97) with an overall mean of 0.67 (95% CRI: 0.47–0.85). A hierarchical modeling approach enabled us to estimate spatial variation in survival of the African reed warbler across the African subcontinent from sparse data. Although we could not confirm the global pattern of higher survival in less seasonal environments, our findings from a poorly studied region contribute to the study of life-history strategies. DA - 2014 DB - OpenUCT DP - University of Cape Town J1 - Ecology and Evolution LK - https://open.uct.ac.za PB - University of Cape Town PY - 2014 T1 - Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns TI - Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns UR - http://hdl.handle.net/11427/1010 ER -	en_ZA
dc.identifier.uri	http://hdl.handle.net/11427/1010
dc.identifier.vancouvercitation	Jansen Dorine YM, Abadi F, Harebottle D, Altwegg R. Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns. Ecology and Evolution. 2014; http://hdl.handle.net/11427/1010.	en_ZA
dc.language	eng	en_ZA
dc.publisher	John Wiley & Sons Ltd.	en_ZA
dc.publisher.institution	University of Cape Town
dc.rights	Attribution 3.0 United States	*
dc.rights.uri	http://creativecommons.org/licenses/by/3.0/us/	*
dc.source	Ecology and Evolution	en_ZA
dc.title	Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns	en_ZA
dc.type	Journal Article	en_ZA
uct.subject.keywords	Avian life history	en_ZA
uct.subject.keywords	capture–mark–recapture	en_ZA
uct.subject.keywords	JAGS	en_ZA
uct.subject.keywords	multistate state-space	en_ZA
uct.subject.keywords	seasonality	en_ZA
uct.subject.keywords	spatial variation	en_ZA
uct.type.filetype	Text
uct.type.filetype	Dataset
uct.type.filetype	Image
uct.type.filetype	Interactive Resource
uct.type.publication	Research	en_ZA
uct.type.resource	Article	en_ZA