Can cockatiels eat sunflower seeds

Yes, of course they can. They split open any type of seed like that and eat the inside of them. It's not good to only give them sunflower seeds to eat without a mixture of a balanced diet. Such as: 30% seed mixture the rest in pellets and fresh vegetables.

(comment edited by Tylor)

Although they can eat sunflower seeds.. it isn't good for them, Most birds when they eat sunflower seeds make them extremely mean, you can search it on many sites.

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The first cockatiel I owned died from fatty liver disease, caused by eating too many sunflower seeds (according to my vet). It should not be a significant part of their diet.