April 7: International Beaver Day

Céline Arétin, culture, women's issues and environment correspondent, April 7, 2025

Characteristics of the beaver

The beaver is a semi-aquatic rodent that measures on average 75 to 100 cm long, not counting its flattened tail which can reach 30 cm, and weighs between 15 and 30 kg. Its teeth, strong thanks to a high iron content, allow it to gnaw wood to build dams and lodges. Its webbed hind feet give it excellent propulsion in water, while its tail acts as a rudder and allows it to store fat reserves. Able to dive for more than 15 minutes by closing its nostrils and ears, it can also carry materials underwater thanks to lips that close behind its incisors. Its diet consists mainly of bark, leaves and aquatic plants.

The beaver's ecological role in its environment

By building dams with branches and mud, it creates wetlands that promote biodiversity. These ponds retain water, reducing the risk of flooding and improving water quality by filtering sediment. Beaver dams slow the flow of rivers, allowing water to better infiltrate the soil and stabilize water levels during periods of drought. These impoundments support the presence of many species such as frogs, dragonflies and various water birds that find refuge in these habitats.

Dangers facing beaver populations

The destruction of their habitat due to urbanization, agriculture and the channeling of waterways is reducing the areas suitable for them to settle. Beavers are also victims of river pollution, which alters water quality and reduces the availability of their food resources. Historically, the beaver nearly disappeared from Europe due to intensive hunting for its fur and the castoreum used in perfumery. At the end of the 19th century, only about 100 individuals remained in the Rhône valley, compared to several thousand previously. Thanks to protection and reintroduction measures, beaver populations have grown, reaching around 14,000 individuals in France today.