I raised a feral earlier this year as Biophiliac and the others know and he was a little monster cleanliness wise a pain to feed too so he always had something on his feathers! Pigeon don't seem to take baths until fully feathered and don't seem very water proof till a few weeks post that :/ I found waiting till after a meal or evening when they're tired is the best time to groom them whith your fingers or tweezers to get gunk off. Its also a bonding thing that they kinda enjoy. Now my boy has his own mate & flock and doesn't need me but he still says hello and claims me as his property in the loft XD