"Some of them are not as lucky and they get grabbed by the head. And that's where you get the teeth going into their eyes and blinding them.''
Mrs Jefferson, who owns dogs, said it was up to owners to better control their animals.
"There's a heck of a lot of responsible dog owners out there but there's others who are not.
"I just think dogs should be under control. That's all it is,'' Mrs Jefferson said.
"I have no objection to the dog being off the leash if it's nearby, but if it's 200m down the beach then they're not being controlled.''
The penguins are likely to remain in danger until the end of summer.
Adult penguins were currently moulting, which meant that for three weeks they were not waterproof and must remain on land.
There were also plenty of young birds in the area following the summer breeding season and they can be easy prey for curious dogs, Mrs Jefferson said.