Skip to main content
Dryad logo

Data from: Senescence in the city: exploring ageing patterns of a long‐lived raptor across an urban gradient

Citation

Sumasgutner, Petra; Koeslag, Ann; Amar, Arjun (2019), Data from: Senescence in the city: exploring ageing patterns of a long‐lived raptor across an urban gradient, Dryad, Dataset, https://doi.org/10.5061/dryad.05qfttdz4

Abstract

In many vertebrates, productivity and survival usually increase with age and then start to decline above a certain age; processes known as reproductive and actuarial senescence. Senescence is widely believed to be driven by the accumulation of somatic damage or mutations. Thus, levels of such cellular damage, and therefore senescence could, in theory, differ between different habitats if they experience different stressors. Urban environments expose animals to a wide range of stressors that pose a challenge to physiological systems and might accelerate the ageing process. We studied productivity and survival of Black Sparrowhawks across an urban gradient in Cape Town, South Africa. We hypothesise that productivity and survival will first increase with age, but that productivity and survival will then decline above a certain age, due to senescence. Furthermore, we hypothesise that rates of senescence will be accelerated in more urban areas. We used 17 years of data from colour-ringed individuals. We found no indication of any improvement in productivity with age in early-life, but we did detect reproductive senescence, with productivity declining above 6 years of age. However, contrary to our predictions, there were no differences in reproductive senescence along the urban gradient. Similarly, we found that survival rates of adults did not show any strong improvement with age in early life, but decreased with age amongst older birds, providing support for actuarial senescence. However, once again no differences in this pattern were apparent along the urban gradient. This study represents one of the first to examine differences in senescence rates in different habitats. Our results suggest that for this urban adapted species, senescence patterns do not vary according to levels of urbanisation. Whether this pattern holds for species more sensitive to urbanisation remains worthy of exploration.

Methods

Data from: Sumasgutner, P. , Koeslag, A. and Amar, A. (2019), Senescence in the city: exploring ageing patterns of a long‐lived raptor across an urban gradient. J Avian Biol. Accepted Author Manuscript. doi:10.1111/jav.02247

Usage Notes

Excel table with 4 sheets: i) first sheet contains all raw data needed to model age dependent productivity; ii) second sheet contains the according legend/data description; iii) third sheet contains all raw data needed to model apparent survival and encounter probability; and, iv) fourth sheet contains according legend/data description.