The team checked the traps about every two hours for three days and four nights because the shrews die if they don’t eat every few hours, making them difficult to capture alive and photograph.

“The hardest part of getting the photos was, one, they’re incredibly fast cause they’re always running around,” Subramanyan told CBS News.

The trio set up a white background on the bottom of the box that held the shrew and glass on the top so they could take the photos, according to the news outlet.

The Mt. Lyell shrew was known to reside in just a few locations in the central Sierra Nevada near Mt. Lyell but, in recent years, has spread to communities on the central and eastern slopes of the Sierra, according to the California Department of Fish and Wildlife.