The animal welfare charity is concerned the birds have been gaining access to waste products from a local brewery or alcohol producer.
RSPCA officers have collected a number of birds exhibiting the same symptoms in recent weeks.
Birds from places such as Dawlish, Seaton, Colyton, Exmouth, Exeter, Sidmouth, Starcross and Budleigh Salterton have been treated.
Man dead due to 'bad batch' of herion
A major incident was declared in North Devon
Teen pregnancies falling in Devon
Number has been broadly trending down since 2015
Dental van on way to Devon to help tackle treatment crisis
It will help tackle treatment crisis in hard-to-reach communities.
Misconduct inquiry into suspended chief constable suspended
Frustration at pace of investigation
Good time for dolphins in Torbay
VIDEO: Happy pods spotted
