These truly amazing birds are sometimes known locally in Trinidad as diablotin (pigeon French for "little devil").
Dunstan cave in the grounds of the AWC is the most accessible Oilbird colony in the world & a free guided trip to see them is part of the package for those who stay for three or more nights at the centre. Flash photography is not allowed in the grotto & so this series of images were taken at a high ISO setting by the light of the guides hand-torch.