Cockatiel
The crest is a mood gauge: straight up is alarm, flat back is anger, and relaxed sits halfway between. Australian, and the males are the whistlers.
Overview
Cockatiels are the bird that turns people into bird people. They are small parrots from Australia, they live 15 to 20 years, and a hand raised one will sit on your shoulder while you work without being asked. That last part is why they beat budgies for most first time owners, and it is also the thing that goes wrong most often, because a cockatiel that was not handled as a baby stays flighty for life.
The males whistle and learn tunes. The females mostly do not, and anyone telling you otherwise is selling you a male. Colour comes in a long list of mutations, and the rarer ones, pastelface, creamface, whiteface lutino, yellow cheek and fallow, cost more than a normal grey because there are fewer people breeding them properly.
Temperament
Friendly, loud in short bursts, and needier than people expect. A cockatiel wants to be in the room with you, not necessarily on you, so a cage in a hallway is a miserable setup and a cage in the living room is a happy one.
They scream when they lose sight of you. That is a flock call rather than a behaviour problem, and it mostly settles once the bird trusts that you come back. Males display and whistle at anything shiny. Females tend to be quieter and a little more standoffish, which some people prefer.
Care and grooming
Here is the part nobody mentions before you buy one: cockatiels are dusty. They produce powder down, a fine white powder that gets on the furniture, the television and you. An air purifier near the cage is not optional if anyone in the house has a chest.
Nails and beak wear down on their own with the right perches, so skip the sandpaper covers, which shred feet. Seed alone is not a diet: pellets, plus fresh vegetables and fruit, plus a vitamin and mineral supplement for breeding birds.
Living and exercise
Get the widest cage you can fit, not the tallest. They fly sideways rather than up. Bar spacing under five eighths of an inch, or they will get a head through it.
They need out of cage time every day, an hour at minimum, and the room has to be prepared for it: windows covered, ceiling fan off, other pets out. Most cockatiel injuries happen in the first month, to a bird that flew at a window it did not know was there.
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