A spokesperson from the South Essex Wildlife Hospital, said: "We had a very hectic day yesterday. As usual everyone was late going home and just as Joe was leaving we had a frantic call needing help for an injured goose. "Joe raced to Gloucester Park in Basildon where he found 2 birds killed and 2 birds injured by vandals with catapults. "All birds had fractured skulls so we had no option but to euthanize the live birds, the geese that Joe managed to spot and catch. "This was just in one area, there may well be other injured birds elsewhere in the park. The police attended.