Imagine walking the beaches of Katmai National Park and Preserve and finding 2,033 dead seabirds in one week. That's what happened in March 2016, when biologists surveyed the park after back-to-back years (2015 and 2016) of enormous die-off of birds, particularly common murres.

Scientists believe the record die-off is linked to unusually warm ocean temperatures the past several years, which impacted fish populations that birds like murres feed on. And they expect the trend to continue.

The National Park Service was assisted in the survey by biologists with the U.S. Fish & Wildlife Service and U.S. Geological Survey.