African researchers on mission to protect wildlife and ecosystems

Imagine you’re a bird. It’s a hot day and you’re sitting on a rock. The temperature in your little body is soaring. So to cool down, a lot like a dog, you begin panting (yes, birds pant).

However, when you do this you lose water, which might be hard to come by.

How about flying up to a tree and finding some shade?

Yes, but are there trees? And will it be sufficiently cool in the branches?

Especially in hot, dry places, birds face a real risk of dehydration and a trade-off must be made between regulating body temperature and conserving water, says climate change biologist Dr Shannon Conradie.

Dehydration dilemma

Birds, indeed all living creatures, live in thermal landscapes — where heat varies at a micro and macro level for a host of reasons, from topography to tree density.

Conradie, who provided the bird example, was speaking at a Tipping Points webinar hosted by the Oppenheimer Generations Research and Conservation, which showcased the three finalists for this year’s $150,000 Jennifer Ward Oppenheimer (JWO) Research Grant.

The winner of this year’s grant, awarded in honour of the late Jennifer Ward Oppenheimer, will be announced at the 13th Oppenheimer Research Conference, which takes place in Midrand from 9-11 October.

Ward Oppenheimer‚ a Harvard-trained lawyer, was well known for her African philanthropic efforts and was a joint founder of The Brenthurst Foundation‚ which brings together the world’s leading thinkers and practitioners to promote economic growth and development in Africa.

The JWO grant encourages African-led research in the environmental and allied sciences, with an eye on tackling important real-world problems. This year’s JWO application process attracted 697 research proposals from 36 African countries.

The finalists

At the recent Tipping Points webinar, Conradie, a postdoctoral research fellow at the University of Cape Town, was joined by fellow JWO grant finalists, aquatic ecologist Dr Nompumelelo Baso and entomologist Dr Steve Baleba.

Robert Inglis, the director of Jive Media Africa, who facilitated the online seminar, invited the three finalists to talk about their proposals and what inspired them.

Conradie said she intended to develop a model that could be used to predict the vulnerability of different species in different places, including their ability to reproduce, in the face of a warming world.

Climate change biologist Dr Shannon Conradie. (Photo: supplied)

Conradie said that if we could map thermal landscapes and combine these with insights into the physiology and behaviour of particular species on the ground (or in the water), then we can develop appropriate conservation and management policies and efforts.

Describing herself as “passionate and curious about the relationship between environments and animals”, Condradie said her project would focus on defining different landscapes in sub-Saharan Africa. However, she hopes to develop and test a model that can be applied globally and to whole systems of organisms, including mammals, birds and reptiles, to better preserve the world’s biodiversity.

The model would be mathematics and physics-based and draw on data gathered using remote sensing, satellite imagery and Lidar.

Aquatic ecologist Dr Nompumelelo Baso. (Photo: supplied)

Baso’s proposed project also deals with the effects of climate change, and she too hopes to develop a predictive model. However, her focus is on the freshwater ecosystems that many Africans depend upon for food and water.

She wants to get a handle on the extent to which long-term shifts in temperatures and weather patterns combined with a proliferation of invasive species affect these natural systems.

Her project would seek to understand the link between climate change and alien invasions and how native species are adapting. It would also explore the role of “biological control”, including deploying natural predators, parasites and pathogens to curb invasive species.

Ecosystem dynamics

Baso, a postdoctoral fellow at the South African Institute for Aquatic Biodiversity in Makhanda (formerly Grahamstown), said she was interested in how climate change and invasive species affect producers at the base of a food chain — say, bacteria, phytoplankton and algae in an aquatic system — and how this affects other levels in the chain.

“So what happens when we have an invader as the primary producer in the systems? That's one of my questions. And then what happens when we have an increase in temperatures, an increase in rainfall events? What does that mean for the overall trophic chain in these ecosystems?” she said.

The project would draw on data collected at invaded and non-invaded sites by collaborators in a “huge study area”, that includes sites in Kenya, Madagascar, Zimbabwe, Namibia, Botswana, Lesotho and South Africa.

Simulation

Baso’s team would also simulate environmental change, including temperatures and nutrient levels, in lab experiments.

“Once we’ve done that we can then build our predictive models to help forecast how invasion by specific species will affect the trophic food webs.”

This would help managers and policymakers “predict, and successfully manage invasions pre-emptively”, helping to protect vulnerable ecosystems and communities.

Entomologist Dr Steve Baleba. (Photo: supplied)

Baleba’s project is about looking after the bees, butterflies, hoverflies and other vital pollinators without whom our dinner plates would look, at best, decidedly dull and at worst, worryingly empty.

Baleba, who is based at the International Centre of Insect Physiology and Ecology, spoke about how farmers, including in his native Kenya, are increasingly using pesticides, which contaminate soil, water and crops while devastating pollinators.

Preserving pollinators

“These insects have to fertilise plant ovaries with pollen. And if this fertilisation process does not occur, we won’t have enough cucumber or tomato. Also, we won’t have enough grapes and apples,” said Baso.

His project would seek to stem declining pollinator populations by discouraging farmers from using pesticides on their crops while training them in natural alternatives.

Baleba said he wanted to identify degraded sites in East Africa that could be restored, including by planting indigenous flowers. At the same time, his team would help farmers in neighbouring restored sites to protect the environment while increasing their yields.

Inspiration

Inglis wanted to know what had set Baleba down this particular research path.

He said that while pursuing postdoctoral work in Germany (on the effect of temperature change on insect chemical ecology) he watched many documentaries and read reviews that flagged a significant reduction in pollinators in Africa, linked to over-reliance on pesticides and habitat destruction.

He also noticed wildflowers blooming in abundance in the German summer and with this, huge populations of pollinators, including bees.

“I thought I could go back to Africa and combine the culture of flowers and the use of biological control tools to mitigate the decline of populations of pollinators that we are having on our continent.”

He was back home in April when calls for the JWO Grant went out and he snapped into action.

What outcome would he like to see if his proposal wins selection?

“To provide more arguments or information that will convince farmers to reduce their dependence on pesticides and adopt more sustainable agricultural practices,” he said.

Bio-control

Replying to the same question, Baso provided a tangible example from the world of aquatic biology.

Amazon frogbit, a fast-growing floating plant, was “taking over in Zimbabwe”, she said. At some point it might spread to South African waters, posing a problem here.

“My model would help us predict how the invasion by that species, or any other species, would affect our ecosystems and our native populations. If you get an invasion from a specific species, given the biology of that species, how is it going to impact our native populations? And how do we then make sure that we build resistance in our communities, be it by bio-control, be it by other means, to make sure that sensitivity is reduced to the form of invasion?”

Conradie hoped her proposed predictive mapping exercise would inform conversations with policymakers and the public about the importance of biodiversity and prompt the development of conservation action plans to “highlight vulnerable areas”.

“This is what we know the risks are and where the risks are. And this is why we need to do something about it.” DM

The 13th Oppenheimer Research Conference takes place in Midrand from 9-11 October.