Gut microbiomes of elephants altered by livestock in shared spaces

A new threat on the elephant population in Samburu and Buffalo Springs National Reserves, has emerged.

Habitat loss, fragmentation and lately climate change have been considered trendy challenges for the animals that require enormous space for their survival but a new study has raised concern over sharing of the environment with livestock.

This mingling of elephants and livestock in the two protected zones according to scientists from the San Diego Zoo Wildlife Alliance in collaboration with Save the Elephants, has affected the elephants’ gut bacteria in ways that could be harmful to their health.

The study tracked known individual elephants in the two national reserves, and found that when livestock numbers increased, the elephants' gut microbiomes shifted significantly. Microbes commonly found in livestock became more abundant in elephant guts, while beneficial microbes decreased.

“Our analysis revealed that the elephants’ gut microbiomes changed when they shared the reserves with more livestock.

“We observed increases in the amount of the methane-producing genus Methanobrevibacter of Kingdom Archaea, known as prevalent in livestock feces, and decreases in bacterial genera like Roseburia that are known as beneficial to human health,” said Jenna Parker, Assistant Professor of Conservation Biology at Lake Superior State University and lead author of the study.

However, the researchers are admitting that they are not sure if these changes are harmful, but concerning because any shifts in gut microbiomes often signal health problems.

These findings, Prof Parker says, have significance beyond elephant conservation.

Livestock now comprise the majority of Earth's mammalian biomass, meaning livestock-associated microbiome changes could be occurring in wildlife populations worldwide—an environmental impact that has largely gone unnoticed, he argues further.

This is therefore a significant step forward into the discovery of how other species are being affected by the presence of livestock across shared landscapes.

"The health of wildlife, livestock, and humans are interconnected, and more work is needed to better understand how each of these systems impacts the health of the others," said Candace Williams, previously a Senior Researcher at San Diego Zoo Wildlife Alliance, and currently Technical Services Manager, Oxford Nanopore Technologies.

The research was conducted against a backdrop of increasing pressures in the reserves, where livestock numbers fluctuate with seasonal changes and intensifying drought conditions driven by climate change.

“The often-negative impacts to wildlife populations and their refuges from human encroachment are well documented, but this study highlights that previously unrecognized, more subtle impacts also occur,” stated George Wittemyer, Chief Scientist for Save the Elephants and a professor at Colorado State University.

Scientists are certain that a holistic understanding of the interplay between wildlife, humans and their livestock is a critical area of investigation and can benefit all actors in these systems.