Evidence of the impact of climate change on our collective environment has been highlighted by many scientific studies in over the past two few decades. However, there are still many gaps in our understanding of the consequences of global warming and in particular of its effect on biodiversity. Although international communities (e.g. IUCN) often focus on range-restricted species in the polar regions, another often overlooked ecozone are is high alpine habitats, or “sky islands”. Sky islands have large proportions of endemics and their mountain-top locations leave inhabitants with no little opportunity to move to higher (and thus cooler) habitats as their current habitats continue to warm. 

Krista Oswald from the Nelson Mandela Metropolitan University will present the Department of Biological Sciences seminar, with a talk entitled, "Adventures in Rockjumper research:  Life in the ski islands". 

The Cape Rockjumper - a South African endemic bird species – is suffering population declines that are heavily correlated with habitat warming within its current range. Cape Rockjumpers are restricted in their distribution to the mountain slopes of the Western and Eastern Cape provinces: the “sky islands” of southern South Africa. In my MSc, I studied Rockjumper thermal physiology in the hopes of determining why populations are declining specifically in areas with strong warming trends, but I found no evidence that poor physiological tolerance of heat is involved in their intolerance sensitivity to habitat warming. For the current proposed study I intend to investigate other aspects of how rockjumpers respond to climate, to see how both current climate warming, as well as past paleo-climatic events, have shaped the habitat for Cape Rockjumpers. I will examine current gene-flow across their range, past genetic separation from their sister-species (the Drakensberg Rockjumper), and behavioural and reproductive changes on days with varying temperatures. In so doing, I hope to better understand how the Cape Rockjumper (as well as similar sky island species) will respond to increasing temperatures, and hopefully identify the mechanism behind the Rockjumper’s declining population.