Police are trying to track down the owner of the dog.
It's the second incident in a month - although the first bird survived.
But on Friday, a man's dog killed a black female swan which recently lost her cygnet. Passers-by tried to intervene to protect the bird but she died from her injuries. The cygnet's father also tried to get the dogs off its mate.
Town Clerk Andrew McKenzie says action will be taken place against irresponsible dog owners.
Ivybridge new supermarket plans rejected
'It’s a site for something'
Skybus rescues Newquay to London flights
Cornish company to operate daily services
Sidmouth pub will keep noise lower during Folk Week
'Rolling in the Deep' was too loud last year
New public woodland could be acquired in Plymouth
Council expected to pay up to £270,000 for land
New solar panels could be on the way
Former Cornwall Council leader quits Conservatives over 'racist' remarks
Pauline Giles apologises
