PhD study tracks changing birdlife in Kruger National Park

BIRD communities inside the Kruger National Park flew under the radar for many years, until Rion Lerm tackled the subject in his PhD research.  

The functional ecologist who graduated from UKZN this week, addresses a significant knowledge gap in African protected area research through his thesis titled: Bird Distribution Dynamics of the Kruger National Park and Surrounds: Drivers and Diversity. 

He also examined how factors such as drought, seasonal change, and environmental conditions affect bird diversity and function.

“The project was centred on protected areas and it was specifically focused around Kruger National Park, which is in the top five largest protected areas in Southern Africa, and the top 20th largest protected area in Africa, specifically with regards to Savannah protected areas. So it’s a significant area and from 2003 to 2013, there were over 500 scientific publications that emanated from this place.” 

Lerm’s study provides insight into the local and landscape drivers of avian diversity, and the impacts of drought on birds. 

It also highlighted the Park’s major role  in conserving the region’s bird diversity and the significance of citizen science data to detect patterns over large geographical areas.

Lerm, who is based at the South African Environmental Observation Network (SAEON)’s Ndlovu Node in Limpopo, used a mix of high-resolution satellite imagery and data from the African Bird Atlas Project, a citizen science initiative, to map long-term trends in bird distribution. His findings, according to UKZN, offer critical insights for protected area managers and conservation scientists working to maintain biodiversity in the face of climate change.

However, while the Park might be one of Africa’s most iconic conservation areas and frequently visited by people from around the world, this could be detrimental to its avian inhabitants, said Lerm. “The camps that we favour and where we go to relax, are detrimental to certain biodiversity metrics for birds because of the development and infrastructure in the area.” 

His research also examined the impacts of extreme weather events such as drought as well as seasonal and environmental variables like tree cover, water availability and ambient temperatures inside and outside the Park which have significant impacts on bird diversity. 

In 2015 and 2016 the Park was affected by extreme weather in the form of drought. 

“We actually saw no real impact of the drought on the birds, believe it or not. And that showed to us how resilient the bird community is to the environment and to things like drought, at least over the single season drought. There's evidence out there that if this drought was prolonged, we may have seen a different picture.” 

In terms of migration patterns since the first study was done,  Lerm found that: “African birds that migrate within Africa, up and down, had a reduction in relative abundance, their numbers have come down. There are specific species there that have suffered more than others while some have increased. So with the African migrants, their numbers reduced significantly. I think up to 20% or a little bit more compared to the Palaeo-Arctic ones from the northern hemisphere.” 

He stressed the importance of citizen science in research saying that studies like his were made possible because of the data collected by citizen scientists.