Soft release of blue-tailed skinks a success

In August 2018, Christmas Island National Park embarked on an ambitious project to save the blue-tailed skink, an endemic species now believed extinct in the wild. The project saw a group of skinks released into a rehabilitated, forested site within the park.

Blue-tailed skink

The soft-release site was extensively modified from its original condition. We removed all original rocks and fallen trees from the area before spraying it to eliminate centipedes (some 160 centipedes were removed from the site).

Approximately 30 tonnes of rocks and furnishings were then brought in and a 1.2 metre electrified fence was erected around the site. The fence keeps out centipedes and wolf snakes, thought to be the main cause of blue-tailed skink loss in the wild.

Aerial photo of the soft-release site

170 skinks ranging in age from juvenile to adult were released into the rehabilitated site in August last year. Since then, the population has been constantly monitored by University of Western Australia PhD candidate Jon-Paul Emery as part of a National Environmental Science Program (NESP)–sponsored project.

After eight months of monitoring, including mark-recapture and distance sampling, Christmas Island National Park is pleased to announce that the blue-tailed skink population is now flourishing. The population appears to be rapidly increasing with many new recruits through successful breeding.

Observers monitoring the skinks were astounded to see the number of hatchlings over the past few months, especially considering the very hot, dry conditions at the time. But blue-tails are a very adaptive species and were able to find areas where they could successfully hatch their young.

Blue-tailed skink

We are confident that this important species will continue to thrive in the release site and are expecting to complete another site later in 2019.

Further research into controlling the known threats to blue-tailed skinks is essential before we are able to release them back into the wild.