Book of Spells Full Transcript
I'm not sure how canon "Wonderbook: Book of Spells" is considered to be, but if it's of any use to this article I have a near-full transcript of what Miranda Goshawk's famous spellbook has to say about the bird-conjuring charm.
The Bird-Conjuring Charm conjures a small flock of birds from the end of the wand. It’s important to remember that your conjured creatures are not real animals. The more accomplished you become at the spells that create them, the more real the animals will appear but you will be disappointed if you try to keep your creations as pets. They are mere phantoms of your own making.
Of course, creating any living creature out of thin air is immensely difficult. This spellbook is concerned with practical instruction and not with theory, but your teacher will be able to explain the Principle of Artificianimate Quasi-Dominance, which will help you understand some of the many things that can go wrong when attempting to conjure animals from nothing. Severed heads, unidentifiable stumps, terrifying frog-rabbit mutations - all have been created; to the dismay of those who made them (and the horror of those who found them hidden under cushions).
However, for reasons that are still not understood (research continues in the Dept. of Mysteries in the Ministry of Magic) two categories of creature are much easier to create from nothing than any other: birds and snakes.
The Bird-Conjuring Charm calls for two smooth bumps from left to right with your wand.
Of course, you cannot control the birds with this spell alone. Conjured birds will [...] chase away creepy-crawlies. If you stay very still, you may even find your feathered friends are quite happy to sit on your book.