Because some snow birds don't pay attention to the laws and they feed them.
It is a busy park. People feed the birds.
Because there are many people there with food and the TOURISTS feed them thinking it's cute.
Looking for a handout from tourists
Because they are looking to be fed
Tons of fish and crustaceans
Because people feed them
Basically what Lee said. Too many people sit there and throw food out for the gulls and the like thinking the bloody rats with wings are cute or make funny noises.
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