Demographic clines and other interesting life-history patterns

Associate Professor Res Altwegg will present the Department of Statistical Science seminar with a talk entitled, "Demographic clines and other interesting life-history patterns". 

Abstract: I'm going to present some of our recent work in animal demography. Among birds, there are interesting global gradients in survival and reproduction. Using hierarchical capture-mark-recapture models and Bayesian meta-analyses, we examined whether these gradients also held within Africa. Among 17 bird species-pairs, more temperate species from South Africa laid larger clutches and survived better than their sister species in Malawi. Among populations of the African reed warblers, however, we found no gradients in demography across southern Africa. We know relatively little about the demography of most South African species and this is especially true for frogs. We examined variation in survival in Rose's mountain toad, a frog that only occurs on the Cape peninsula. We found that 94% of the variation in survival among years could be explained by variation in rainfall. These results suggest that the frogs make critical life-history decisions in response to weather. Lightfoot's moss frog, another frog species that only occurs on the Cape peninsula is very difficult to find but easy to hear. We developed an acoustic monitoring system involving microphone arrays and spatially explicit capture-recapture methods. This method has given us a powerful tool to monitor these cryptic frogs and learn about their ecology.

Res Altwegg is an Associate Professor in the Department of Statistical Sciences, University of Cape Town. He is also the Director of the Centre for Statistics in Ecology, Environment and Conservation (SEEC). He has a PhD from the University of Zurich



Monday, February 5, 2018 - 13:00

PD Hahn Building Lecture Theatre 3