Tim McKenzie, casualty care manager at East Sussex Wildlife Rescue and Ambulance Service (WRAS), says seagulls being shot with airguns has become a big problem in Eastbourne and Pevensey.
Tim says nine birds have been found injured by airguns in the town this year and the animal charity has taken an additional four anonymous calls from Eastbourne residents about shootings.
"Shooting does not kill the gulls so most fall to the ground and die slowly or drown in the sea," said Tim. "If people don't want the gulls nesting on their roofs and near their homes there are plenty of humane deterrents.
"Herring gulls are rapidly becoming an endangered species as there are only 200,000 left in the UK."
Tim added, "In Stone Cross a bird fell out of the sky and nearly hit a group of children. So even if people don't care about the beautiful gulls what about the children? "
The charity says it has had similar problems in Hastings, Bexhill and Brighton but police in those areas have worked to stop the shootings. WRAS is now calling on officers in Eastbourne to do the same.
A police spokesperson said, "WRAS, working in partnership with Sussex Police, is concerned about the number of recent incidents involving the shooting of seagulls.
"Any incidents reported to Sussex Police will be fully investigated."
Officers are now appealing for witnesses in relation to the latest incidents in Acacia Road on April 11 and in Rylstone Road on April 13.
Witnesses should call 0845 60 70 999, quoting serial 851 of April 12 for the Acacia Road shooting or 409 of April 14 for the Rylstone Road incident.