But they are only wanted for eradication.
The council runs its annual rook-control programme from September to November, asking the region's residents to keep a lookout for the pest birds and their nesting sites.
Its best weapon to achieve its goal of eliminating rooks was ''the thousands of eyes and ears'' of the people on the land, the ORC said. The council has been able to reduce the rook population from several thousand birds to about 60.
Members of the crow and raven family, their black feathers often have a purple or bluish sheen in bright light.
Council environmental monitoring and operations director Jeff Donaldson advised people who saw rooks not to scare them. There was often only one chance to deal with rooks, and if disturbed they could scatter to form new rookeries, he said.
''Anyone who sees a rook or rookery just needs to give us a call and our pest eradication staff will come and deal with them as a free public service.
''Of particular note is that there have been no reports of new rook chicks in Otago over the past three years, and that we may now have a non-breeding population,'' Mr Donaldson said.
Sightings can be reported to Malcolm Allan by phoning 027-278-8498, via the council freephone 0800-474-082 or by emailing to: info@orc.govt.nz.