Palmate newts in garden in Oss (the Netherlands)

The author reports the presence of a seemingly isolated population of Palmate newts (Lissotriton helveticus) in his garden in the town of Oss. Their behaviour could be observed for a period of twenty years. During spring and summer the adult newts are found in the garden ponds. Eggs are mainly deposed in May and June, but this may continue until August. Adult males predominantly hibernate in the water. A good part of the female and juvenile Palmate newts hibernate on land. How they became settled in the garden remains unclear since their presence in the direct environment has not been confirmed previously. Evidence of active introduction in the neighbourhood was not found.