The DSPCA is appealing to dog owners to keep their pets on a lead after a swan was attacked along the Royal Canal.
The animal welfare charity says the swan fought back and tried to protect her eight eggs - but the dog had pulled off one of her wings and she had to be put asleep.
The group says the horrendous incident could have been avoided.
Commenting on the incident, Gillian Bird from the Animal Welfare Group said:
"People, unfortunately, aren't being responsible dog owners, they're letting their dogs off. They're letting their dogs attack these animals. And it ended up with the poor swan losing its life".
She added: "There were 8 eggs at the nest, they were disturbed and unfortunately they didn't make it either. It's one of those tragic things because swan's mate for life for a start, so the poor male is left there now. And in the situation of this poor swan, she was savagely attacked."
