Species as

Ecosystem Engineers

THE BEAVER

Adrian Lloyd JonesNorth Wales Wildlife Trust

The Welsh Beaver Assessment Initiative

• Wildlife Trusts Wales is the lead organisation.

• Management team includes representatives from WTW, CCW, EAW, FCW, Wild Europe and key individuals.

• Primary aim is to investigate the potential for a beaver reintroduction to Wales

Probable distribution of European beaver in

Europe (outwith Russia) after the last Ice Age

(Halley, D & Rosell, F. - 2002)

Beaver distribution by late 19th Century

1. Telemark, Norway. c.1002. Elbe, Germany. <2003. Rhône, France. c. 304. Pripet Marshes, Belarus. <400

Approx population: 1,200 animals

• Pelt (very dense and warm, also for waterproof hats)• Meat (especially during lent)• Castoreum (general remedy)

Landscape change generally unimportant

Present day distribution

Why reintroduce the beaver?

• Legal: Article 22 of the EC ‘Habitats Directive’.• Biodiversity: a ‘keystone species’ in the ecology of

riparian woodlands and wetlands.• Environmental benefits: water quality & quantity.

Socio-economic benefits: public interest, wildlife tourism.

• Moral argument: a species lost through human actions.

Beavers manage wetland ecosystems by...

• Feeding activity – grazing, coppicing trees

• Building activity – dams/ponds, lodges

• Digging activity – burrows, channels

Feeding

Fallen and standing deadwood

Building

Dams

• Aim to achieve a depth of 0.7 – 1.0 metre• Keeps entrance submerged• Enables diving (for predator evasion)• Deeper water enables movement under ice• Easier transport of food and building materials

Easier access to food sources

1964 1967 1992 1994 2002

9

10

8 8

18

0

2

4

6

8

10

12

14

16

18

20

Fis

h s

pe

cie

s

[N]

Beaver dam 1995

Beavers increase number of fish species

Building and Digging - Burrows and Lodges

Beaver Canals

Beavers in a human influenced landscape

BEAVER PROBLEMS

Feeding on crops• Real damage mostly

minor

Felling trees• No real habitat damage

BEAVER PROBLEMS

Damming• Flooding of man used

areas• Blocking water courses

Digging• Burrows under fields• Burrows in dams and dikes

• Electrical fences

• Protection for trees

• Removing dams

• Protecting culverts

• Trapping problem beavers

• Public relations

Many solutions to problems

Beaver trap baited with apples

Where do problems occur ?• 98% of all problems are within 20m from the water's edge

(95% of all beaver activity within 10m)

Llanbwchwyn SSSI. 67 acres

Radnorshire Wildlife Trust

Biodiverse Beaver Landscapes

Thank you