Considering that the name is "seed-eating", the birds eat seeds, not trees.
worms
A bird-eating-spider eats birds
There are some seed eating birds that feed at different times to avoid competition. Others do it to avoid conflict from other birds, and some eat with other birds.
well, if it eats normal birds, whats the difference between eating a smaller bird?
A bird eating spider that's it :)
Large birds and snakes are known for eating "Tarsiers"
Mostly smaller birds eat "bird seed" such as budgies and other small parakeets.
I think I saw a paper wasp eating one of mine.
A bird that only eats seeds, is a herbivore.
If they are dead, carrion-eating-birds of prey, such as vultures, eagles, and hawks.
I've never heard of a seed-eating bird... but if there is such a thing then yes, they would be a consumer.