Veterinary drugs pushing dung beetles to the brink of extinction

Sept. 24 (UPI) — Farms and ecosystems could soon be without the soil-churning services of dung beetles, according to a new study. Researchers suggest drugs used in veterinary medicine are pushing the beetles to the brink of extinction.

Through a series of field tests and lab experiments, scientists in Mexico determined that “native and exotic species of dung beetles are highly sensitive to different types of livestock management.”

Researchers at the National Autonomous University of Mexico subjected test beetles to an antiparasitic drug and herbicides commonly used in intensive animal feeding facilities. The compounds altered the beetles’ growth and development patterns, limiting their ability to perform their normal ecological services.

In forests, grasslands and deserts all over the world, dung beetles collect and eat animal excrement. Their unique lifestyle offers a variety of benefits, including seed dispersal, nutrient cycling and parasite suppression. They also aid the sequestration of greenhouse gases.

But as the latest study makes clear, dung beetles are one of the most threatened terrestrial animal groups on the planet.

The latest research — published this week in the journal Environmental Toxicology and Chemistry
— showed the specific physiological response to each drug and herbicide depended on the sex and species of the dung beetle.

But as scientists previously demonstrated on cattle farms in the Mediterranean, dung beetles are harmed by pharmaceuticals and herbicides. The tested compounds survive the ride through a cow’s intestines and remain active in dung for weeks, exposing dung beetles to their deleterious effects.

According to lead study author Daniel González-Tokman, the latest research can help scientists “understand the underlying mechanisms of species decline in nature and enrich the strategies of livestock management with benefits for grassland ecological health.”

Researchers suggest farmers and ranchers should work to protect dung beetle populations to ensure the insects continue providing their valuable ecosystem services.