Animal Carcasses: Revitalising the Ecosystem

Animal carcasses play an important role for biodiversity and the functioning of ecosystems — including over longer periods of time.

These findings have been published by scientists from the German Centre for Integrative Biodiversity Research (iDiv) and the University of Groningen in the journal PLOS ONE .

Carcasses not only provide food for many scavenging animal species — their nutrients also contribute to significantly enhanced growth in surrounding plants. This in turn benefits many herbivorous insects and their predators. The researchers recommend relaxing legal regulations that require the removal of carcasses in nature reserves.

Insects and Plants Benefit from Animal Carcasses

In the Dutch wilderness reserve Oostvaardersplassen, one of the largest wetlands in Central Europe, scientists investigated how carcasses of red deer affect local biodiversity. They recorded the occurrence of insect species in areas with and without carcasses, as well as plant growth in the immediate vicinity of the carcasses. They found that carcasses not only directly benefit many carrion-feeding insects such as flies and carrion beetles, but also have a long-term positive effect on plant growth.

A Beneficial Influence Lasting Months

Plants such as the curled thistle (Carduus crispus) grew more than five times as large near the carcasses as at other locations, which in turn increased the number of herbivorous insects and their predators fourfold. “That animal carcasses are important for scavengers may not seem surprising at first”, says lead researcher Dr. Roel van Klink. “That they would still have such a large influence on the entire local food chain after five months, even on soils as nutrient-rich as those in the Oostvaardersplassen, was not something I would have expected."

Not just deadwood

The results shed new light on the role of animal carcasses in the ecosystem. “Deadwood in our forests is now largely accepted by the public, which benefits many species”, says Prof. Chris Smit of the University of Groningen. “The sight of dead animals in nature is, however, often still a social taboo. This is a shame given their important value for ecosystems and biodiversity”. In addition, EU regulations make it difficult to leave carcasses of large animals in nature reserves. The authors recommend relaxing these rules for nature reserves.