LOS ANGELES — Mira Tweti does plenty of squawking over the size of parrot cages. Most, she says, are too small for the colorful birds whose charismatic and intelligent natures make them popular pets.

That’s why the Playa del Rey, Calif., author and journalist is launching a national campaign to encourage parrot owners to swap their standard-size bird cages for larger ones.

Typical bird cages measure 24 inches wide, 16 inches deep and 16 inches high. Parrots need much more than that, Tweti says. “We recommend a minimum of 32 inches in width, 24 inches in depth and 40 inches in height. And the cage should be 3 feet off the ground,” she said.

Tweti’s nonprofit, Parrot Care Project and Cage xChange Campaign, begins this month at a Santa Monica, Calif., exotic bird shop, where free veterinary exams will be available and experts will be on hand to discuss avian nutrition, how to choose the right cage and how to equip it with toys.

Tweti said she hopes to extend the program to 50 cities over the next five years.

Cages should be outfitted with a variety of perches and playthings to stimulate their occupants. Parrots lacking such diversions often pluck their feathers, a habit that usually is impossible to reverse, Tweti said.

“Parrots don’t make good pets,” she said. “... It’s a wild animal kept in a cage. They’re never domesticated. The ideal place for them should be in a rainforest.”

But she acknowledges they make good companions with their musical warbling and knack for repeating humans’ phrases. That’s why there are an estimated 30 million of them residing in living rooms in the United States.

Some parrot owners never take their birds out of their cages. Tweti has a photo of one parrot that had grown so large that it would not fit through its cage door. A bird rescue group had to cut apart the enclosure to free it.