•  pigeon – their feathers fall off very easily, which is a mean of defence against predators. Many predators attacking these birds end up with muzzle full of feathers while the victims escape;
  

• sparrow – these birds are very prying and sociable, a sparrow flew into a hall in Holland, where a hundred people tried to beat a domino Guinness record, and knocked one down, spoiling many-month work;
  

• starling – most birds can imitate almost every sound; it was noticed that starlings learnt to imitate a high-pitched, modulated sound of car alarms;
  

• sea gulls – sea gulls of Ustka became very lazy and do not want to fish. The gulls prefer to sneak from plates and wait for leftovers by tourists eating near the harbour.
  

Control methods: 

• nets
• warning tapes
• gel barrier
• balloons
• dummies
• thorns
• sound signals