Most birds have a poorly developed sense of smell don't taste much either, mostly swallow food whole, probably as a weight economy. Kiwi has the best sense of smell. Recent studies have shown than petrels smell their prey out in the ocean. ROBINS EYE WORMS, they don't listen or smell for them.
Turkey Vultures smell well and locate carrion that way. Pipe companies have added carrion smell and looked for vultures to find leaks but sight may be more important---in the jungle of Ecuador, I met beetle collectors who buried cans of excrement to catch their insects. Vultures could not see or smell the shit, but quickly gathered around, perhaps cued in by the flies around the cans.
EARS. Birds have some of the best hearing of animals, even though they lack pinna (= streamlining). Barn Owls can catch in total darkness. At least two birds use echo-location like bats: Oilbird and Cave Swiftlet. (From the swiftlet comes birds' nest soup: the nests are made of sticks and dried bird saliva.)