RESEARCH IN THE SPOTLIGHT: THE STRUGGLES OF HEDGEHOGS

Hedgehogs are a familiar and loved part of Flanders’ wildlife, but their numbers are falling fast. At Wildlife Health Ghent, we’re investigating why, and what this tells us about the changing health of our environment.

European Hedgehog, Erinaceus europaeus (© Frank Pasmans)

Our researchers regularly perform animal necropsies on hedgehogs received from wildlife rescue centers. Using clinical, histological, and molecular analyses, we investigate how multiple environmental stressors are affecting these small mammals.

One major threat is diphtheria caused by Corynebacterium ulcerans. In recent years, unusually high numbers of infected hedgehogs have been found in Flanders and neighboring countries. The disease causes severe abscesses on the head and limbs, which are often difficult to treat and can be fatal. The reasons for this outbreak are still unclear, but environmental pressures and infections likely interact to allow this opportunistic bacterium to thrive.

Another emerging concern is exposure to rodenticides, chemicals used to control rodents. Our studies have shown that hedgehogs in Flanders often carry high concentrations of anticoagulant residues in their livers, especially in urban areas. These toxins accumulate through the food chain: invertebrates such as slugs absorb them from soil or rodent carcasses, and hedgehogs ingest the contaminated prey.

African pygmy hedgehog, Atelerix albiventris (© Valérie Miserez)

In experimental work with African pygmy hedgehogs (Atelerix albiventris), we found that exposure to brodifacoum, a common anticoagulant, caused small kidney hemorrhages. While these effects were sublethal, they raise concerns about the health impact of long-term, chronic exposure in the wild.

Together, our findings show how environmental contaminants and pathogens threaten the health and survival of hedgehogs. Protecting them means looking beyond individual diseases, and consider the wider pressures they face in our shared environment.

This study is part of Wildlife Health Ghent’s broader research into the health of wild animals. Find out more about our work on our website.