The Otter Lutra lutra in Essex 1996-2002
agement regime and the planting of riparian trees and shrubs would be beneficial in providing shel-
ter for Otters. Artificial log-pile holts can also be constructed and have been shown to be used by
Otters in, for example in Wales (Cowell et al. 2001).
On the navigable and canalized sections of Essex rivers, e.g. the Lea and Stort, pilings along the
banks make it impossible for an Otter to leave the water often for long stretches. If piling occurs
along one side only, then escape from the water is easy but where piling occurs along both banks
gaps should be cut at intervals to allow rapid access to dry land.
In the longer term effort must be directed at restoring riparian habitats and river floodplains in
Essex. This would not only aid the future of Otters in Essex but would be beneficial to floodplain
biodiversity as a whole. It would also lead to many economic benefits for society. Water would be
retained for longer in the system, reducing the risk of flooding to life and property. The long reten-
tion time would allow for the replenishment of groundwaters. The new wetlands would retain nutri-
ents and pollutants, and stabilize sediments, reducing both eutrophication and pollution in the river
and hence reducing the costs of water treatment (Mason 2002). Maintenance costs within the river
would be substantially reduced (Fuglsang 1998).
Acknowledgements
We are grateful to WWF-UK for their financial support of this study.
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