In 2007 it was announced that a colony of Townsend's big-eared bats had settled in the ride's engine room.

These caves house breeding colonies for Townsend's big-eared bat and are closed during pupping season.

The endangered Townsend's big-eared bat is also known to live in the watershed.

It was known that about 45% of the world's estimated 20,000 remaining Virginia big-eared bats hibernate in Hellhole.

Similar to the Townsend's big-eared bat, it has two lumps on either side of its nose.

The big-eared bat is highly sensitive and needs exacting conditions to hibernate.

The mating season for the Townsend's big-eared bat takes place in late fall.

The average lifespan of a Townsend's big-eared bat is 16 years.

The park contains a colony of Townsend's big-eared bats, considered a sensitive species in Oregon.

Cave creatures include the Townsend's big-eared bat and numerous blind, colorless insects.