She spotted four dead seagulls on Flamingo Park’s pond on May 18.
Park staff told her the council would be contacted. She said she saw three more dead seagull in the same spot a week later.
She also found a sick seagull on the beach opposite Cavendish House which died later.
She said: “I wish that someone, anyone would take this matter seriously as I truly believe that someone could be poisoning the or shooting the animals with an air rifle.
"Help is required and its required now as I've seen eight dead seagulls and a fox .”
The Department for Environment, Food and Rural Affairs confirmed the Animal and Plant Health Agency had collected five gulls from Hastings and these had been sent for laboratory testing.
A spokesperson said: "Do not touch or pick up any dead or visibly sick birds that you find. If you find dead wild waterfowl or other dead wild birds, such as gulls or birds of prey, you should report them to the Defra helpline, 03459 33 55 77.
“Wild birds are susceptible to a range of diseases and injuries and not all dead birds will have been infected with avian influenza.
“Where dead birds are not required for surveillance purposes it is the landowner’s responsibility to safely dispose of the carcases.”
Hastings Borough Council confirmed it had been made aware of dead wildlife in the area and it had been reported to the police.
The RSPCA and Flamingo Park have been approached for comment.