It was spring in Queensland, Australia, a season when many wild animals find themselves in trouble, and the Currumbin Wildlife Hospital was a blur of fur and feathers.

A groggy black swan emerged from the X-ray room, head swaying on its long neck. A flying fox wore a tiny anesthetic mask. An injured rainbow lorikeet squawked in its cage. (“Very angry,” a sign warned.)

“We see everything,” Dr. Michael Pyne, the hospital’s senior veterinarian. Also on the schedule for the day: three eagles, two carpet pythons, a blue-faced honeyeater, a short-eared brushtail possum and, Dr. Pyne said, “a whole heap of koalas.”

More than a dozen koalas were convalescing in open-air enclosures, wrapping their woolly arms around the trunks of eucalyptus trees. The wards were often full; in 2023, the hospital admitted more than 400 koalas, a fourfold increase from 2010.

The surge has been driven largely by the spread of chlamydia, a devastating bacterial infection. But the hospital was also seeing more koalas with traumatic injuries, including those caused by cars and dogs. Starving, dehydrated koalas came in during droughts; burned koalas appeared after wildfires. Occasionally, koalas even turned up with injuries caused by cows.

“That’s why they’re endangered,” Dr. Pyne said. “Everything’s against them.”