Brown tree snakes have led to the extinction of five-sixths of Guam’s bird species since they flew in planes 70 years ago. If they reach other Pacific islands, especially Hawaii, it is feared that they may trigger a similar birdpocalypse. Part of the deadly effect of these snakes is in the form of never-before-seen speeds that allow them to climb places other than snakes. Snakes make up for the disregard of four types of locomotion (in addition to gliding and jumping), known as documented rectilinear, lateral indulgence, sidewinding, and concertina mode for nearly a hundred years.
Colorado State University Professor Julie Savidge has now made another observation, which she and co-authors have called “living locomotion”, described in Current Biology. Savage Micronesia is working to save the starlings, one of two species of birds so far that the brown tree snake has been extinct in Guam. Even the starlings have just retained their nail tips, and their loss will have a devastating effect.
Professor Savidge said in a statement, “Sterling serves an important environmental function by scattering fruits and seeds that can help maintain Guam’s forests.” Savidge and others continue to make snake-resistant bird boxes but saw snakes enter into unexpected places. Night-vision videos of snakes on the summit revealed that the rear half of the snake loops around a tree or pole while the front extends like an inverted lasso. Concertina deploys speed to deal with other snake steep peaks, but it also has limitations. Brown tree snakes (Boiga irregularis) by making small bends in the lasso and shifting the position of the bend for other techniques, the snake can climb very wide cylinders compared to the length of the snake.
Co-author Professor Bruce Jayne of the University of Cincinnati said in a statement, “Designing barriers to the spread of fungi and reducing some of the harmful effects of this highly invasive species has a direct effect on understanding how brown tree snakes can and cannot climb.”
Jayne notes, however, that the brown tree snakes also see this new model as a fight. “While they can climb using this mode, it is pushing them towards limitations,” he said. Snakes are seen to stop frequently and breathe heavily in lasso-climbers, sometimes slipping backward. Researchers are keen to use the knowledge of this new snake to creating a vague design even beyond the capabilities of this snake. This will not only save starling but also allow the reintroduction of several species of Guam lost birds from the snake-free islands.
Another important issue is whether brown tree snakes are unique in lasso-climbing, or whether other members of the cat-sighted snake family can do the same. It was once thought that brown tree snakes did so much damage to gums because of their distinctive venom. Recent studies have found that they are a hundred times more deadly to birds than mammals, yet the same is true of many of their relatives, suggesting a similar risk to the island’s population. However, it remains to be seen whether other snakes have the ability to reach the nest.