A team of CEH scientists within the Biological Records Centre recently deployed a couple of camera traps at a site beside the river Thames in an effort to get footage of that often elusive mammal, the otter. Pleasingly, the cameras have managed to capture some short clips of otters, as well as many other animals.

Otter numbers declined dramatically in parts of Britain and western Europe in the 1950s and 1960s. By the 1970s, otters were largely absent from large parts of England and Wales and some areas of Scotland. The widespread use of chemical pesticides was thought to be one major factor, polluting rivers and disrupting the food chain of this top predator. Pesticide bans, improvements in water quality, and conservation strategies to improve river habitat have led to more encouraging recent news however, with otters believed to be making a return to many areas thanks to natural recovery and some reintroduction work.

An American mink was also spotted at the Thames site. This non-native species is much smaller and darker than an otter, and swims higher in the water. More information on American mink can be found from the Non-Native Species Secretariat. You can also read more about invasive species here.

Why record mammals?

Mammals are surprisingly under-recorded in the UK but it is important to build up a fuller picture of their numbers and activity in order to implement conservation strategies.

The Mammal Tracker app aims to make it easier for users to submit sightings of the mammals they see when out and about. Biological recording is not only fun, but useful: the records received are checked by experts and used by scientists working on vital mammal monitoring projects.

The Mammal Tracker app is supported by the Heritage Lottery Fund, the Mammal Society, Nature Locator and the Biological Records Centre, which hosts the data on behalf of the recording community. Drawing on the Mammal Tracker app, the first new National Mammal Atlas for more than two decades is currently in preparation by the Mammal Society with supporting data collation and mapping work provided by Dr Colin Harrower of the Biological Records Centre.

Other wildlife

Of course, the Thames is home to many other animals, with our camera traps picking up a lot of bird activity in particular. Below we share a couple of nice clips of a heron, and a group of Canada geese.

Many thanks to Björn Beckmann, Tom Humphrey and Karolis Kazlauskis for sharing videos from the camera traps. Hopefully we'll have more otter footage to share soon!

Related links

Biological Records Centre

Mammal Tracker app

The Mammal Society

Non-Native Species Secretariat

CEH undertakes long-term water quality and monitoring research on the Thames via the Thames Initiative project

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