RAMANATHAPURAM: Mystery shrouds the death of birds, including Pelicans, an endangered migratory species, at Sakkarakottai tank here. Forest officials of Gulf of Mannar Marine National Park (GMMNP), ornithologists and veterinarians visited the spot on Sunday based on information that some birds were found dead in the tank. Pelicans and egrets were among the birds found dead. Though there were no noticeable wounds in the body of the birds, the stomach part of all birds seem to be cut. It is suspected that they might have died three days ago. It was in the same season and the same spot last year that migratory birds were found dead. It was then suspected that they were poisoned to death. Though there was no report of death of migratory birds since April last year, the issue has come to the fore again. Enquiries with boys in the locality revealed that the birds might have been poisoned again. Gangs involved in poaching of birds usually follow such a practice whenever migratory birds visit the tank