Bird flu has been on the rise in Washington state and one sanctuary was hit hard: 20 big cats – more than half of the facility’s population – died over the course of weeks.

Bird flu ripped through a Washington state wildlife sanctuary, killing 20 big cats, the center said in a Facebook post, calling the deaths a "significant loss."

The animals - including a Bengal tiger, cougars and bobcats - have died of the virus over the past several weeks.