To determine the presence/absence and population size of great crested newt populations certain surveys have to be undertaken. A great crested newt assessment requires four site visits; at each site visit at least three different survey methods should be used.
Egg searches: great crested newts lay their eggs in the leaves of submerged vegetation, which the mother folds over to wrap the egg in. The eggs themselves are whitish in colour and approximately 4.5-6mm in diameter surrounded by a jelly capsule. A female may lay up to 700 eggs in a season, but on average lays 200-400.
The survey includes the systematic searching of suitable vegetation (e.g water mint and floating sweet grass) for the presence of great crested newt egg wraps.
Torchlight searches: after dark, the perimeter of the pond is walked around and illuminated with a powerful torch. Great crested newts are often more active at night so are more likely to be spotted than in the day when they may be hidden in vegetation.
Bottle trapping: Bottle traps (normally made from 2 litre plastic bottles) are set up around the pond margin and are left overnight. In the morning the bottle traps are checked for great crested newts, which are then released.
Netting: A long handled dip net is used to search the perimeter of the pond for great crested newts.