The most notable species listed is the otter which passes through the Fen but with improved management could possibly become resident. Small mammals are probably under recorded but we have recent evidence for water voles:

'His and hers' water vole droppings

Otter print

Otter spraint

Otter kit in the Itchen beside Clausentum Fen 20.45 on 22 May 2017. Thanks to Brian.

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Bank vole
Eurasian water shrew
European mole
European water vole - top middle
Otter - top right
Red fox
Roe deer - top left
Yellow-necked mouse

Stoat - 13.5.18

Brown Long Eared