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Crawling in caves

Lava tubes house creatures and clues to our past

Jamie Hinrichs
Pacific Southwest Region
June 3, 2024

Illustration of a cave with insects, a frog, bats and a sign that reads “home sweet home”.
Join us in Nature’s ultimate crawlspace. (USDA Forest Service illustration by John Eudicone)

*Listen to the audio story: Forest Focus Episode 44: Crawling in Caves

There are portals within many national forests that offer entry into underground realms of the most curious forms of biodiversity. These subterranean chambers and hallways are called lava tubes or caves. Where once molten lava flowed, now tiny creatures creep in the shadows in costumes of faded hues. Their pallor is paired with neighboring life forms that sparkle when hit by a flashlight, as if dusted with glitter. But it's not just the unusual denizens that make lava tubes unique—they are also archives that contain records of our Paleolithic and climatic past. To explore within, a readiness for crawling will be required. Fortunately, we have an experienced caver to show us the way in the latest episode of Forest Focus.

*Listen to the audio story: Forest Focus Episode 44: Crawling in Caves.

A man wearing a vest and green trousers stands in front of a backdrop of leafless trees.
Wildlife Biologist Tom Rickman uses a variety of tools on a chest vest when inventorying the biodiversity of caves, including an aspirator to collect select invertebrates for documentation. Lassen National Forest, 2023. (USDA Forest Service photo by Jamie Hinrichs)