Skydiving salamanders live in world’s tallest trees

Salamanders that live their entire lives in the crowns of the world’s tallest trees, California’s coast redwoods, have evolved a behavior well-adapted to the dangers of falling from high places: the ability to parachute, glide and maneuver in mid-air.

Researchers suspect that this salamander’s skydiving skills are a way to steer back to a tree it’s fallen or jumped from, the better to avoid terrestrial predators.

While they’re parachuting, they have an exquisite amount of maneuverable control, they are able to turn and flip themselves over if they go upside down. They’re able to maintain that skydiving posture and kind of pump their tail up and down to make horizontal maneuvers. The level of control is just impressive. The aerial dexterity of the so-called wandering salamander was revealed by high-speed video footage taken in a wind tunnel at the University of California, Berkeley, where the salamanders were nudged off a perch into an upward moving column of air simulating free fall.

The behavior is all the more surprising because the salamanders, aside from having slightly larger foot pads, look no different from other salamanders that aren’t aerially maneuverable. They have no skin flaps, for example, that would tip you off to their parachuting ability. Wandering salamanders have big feet, they have long legs, they have active tails. All of these things lend themselves to aerial behaviors. But everybody just assumed that was for climbing, because that’s what they use those features for when we’re looking at them. 

Among the questions the researchers hope to answer in future research are how salamanders manage to parachute and maneuver without obvious anatomical adaptations to gliding and whether many other animals with similar aerial skills have never been noticed before.

 The wandering salamander, probably spends its entire life in a single tree, moving up and down but never touching the ground, is a proficient skydiver. A related species, the so-called arboreal salamander, A. lugubris, which lives in shorter trees, such as oaks, was nearly as effective at parachuting and gliding. Researchers discovered that most of their marked salamanders could be found in the same tree year after year, although at different heights. They live primarily in fern mats growing in the duff, the decaying vegetable matter that collects in the junctions of large branches. Few wandering salamanders from the redwood canopy have been found on the ground, and most of those were found dead. Researchers suspect that their aerial skills evolved to deal with falls, but have become part of their behavioral repertoire and perhaps their default method of descent. 

That suggests that when they’re wandering, they’re likely walking on flat surfaces, or they’re walking upward. And when they run out of habitat, as the upper canopy becomes drier and drier, and there’s nothing else for them up there, they could just drop back down to those better habitats. Why walk back down? You’re already probably exhausted. You’ve burned all your energy, you’re a little 5 gram salamander, and you’ve just climbed the tallest tree on Earth. You’re not going to turn around and walk down — you’re going to take the gravity elevator.

Researchers see A. vagrans as another poster child for old growth forests that is akin to the spotted owl because it is found primarily in the crowns of the tallest and oldest redwoods, although also in Douglas fir and Sitka spruce.

This salamander is a poster child for the part of the redwoods that was almost completely lost to logging — the canopy world. It is not there in these new-growth forests created by logging companies,” he said. Perhaps it would help not just efforts in conserving redwoods, but restoring redwoods, so that we could actually get canopy ecosystems. Restoring redwoods to the point of fern mats, to the point of salamanders in the canopy — that would be a new bar for conservation.

Source: University of California, Berkeley