For International Beaver Day, a beaver swimming in Grand Teton National Park, Wyoming, USA

© Charlie Hamilton James/Getty Image

Beavering away. Busy building wetlands

For International Beaver Day, we take a peek at one of nature's most prolific engineers. To the beaver, dams help keep their lodges and litters safe, but their positive impact ripples through the environment: restoring wetlands, combating climate change and removing fertiliser run-off. If we protect their habitat, the beaver will pay it forward by creating the wetlands so many threatened or endangered species rely on.