German cat owners have been ordered to keep their felines inside for months to protect a rare bird during its breeding season

• Cat owners in Walldorf, Germany have been asked to keep their felines inside until the end of August.
• Authorities are trying to protect the endangered crested lark, which nests on the ground.

Pet owners in the German town of Walldorf have been ordered to keep their cats inside to protect a rare bird.

Walldorf cat owners were asked to keep their cats inside until the end of August to protect the crested lark, which nests on the ground, during its breeding season. The lark's population has sharply declined in recent years, according to The Associated Press.

Walldorf authorities said "the survival of the species depends on every single chick," per the AP.

The measure will be repeated for the next three years, keeping cats inside from April to August, The Local reported. If a cat escapes the house, pet owners are asked to try to get it back inside and call the authorities if needed.

Those who ignore the rule could face a €500 fine, and if a cat kills a crested lark, the fine can be up to €50,000.

Some have called the request an overstep. A leader at the local animal protection association is planning to challenge the measure.

"Please remain calm," he said, per AP. "I can assure you we'll do our best to stop this disproportionate measure."