On the 16th February 2003, the Invertebrate team at Melbourne Zoo received a pair of one of the rarest invertebrate species on the planet, the Lord Howe Island stick insect (Dryococelus australis). The pair was affectionally known as Adam and Eve. We knew from the moment they arrived that we had just one chance to secure the long term survival of this Critically Endangered species. To add to the enormity of the task, virtually nothing was known about the species, so around the clock observations were initiated for the first few weeks.
The Lord Howe Island stick insect was abundant on Lord Howe Island until the accidental grounding of a supply ship in 1918. Black rats (Rattus rattus) escaped the grounded vessel, and by the 1930s the Lord Howe Island stick insect was presumed extinct. In 2001, a five-member scientific team landed on Balls Pyramid, a rocky outcrop 23kms off the coast of Lord Howe Island, and miraculously rediscovered a very small and vulnerable population of this “lost” species. This began the significant challenge of securing a population to save them from extinction.
There have been many challenges since this species arrived under the care of the Invertebrate team at Melbourne Zoo, Australia. Since 2003 we have hatched over 10,000 individuals and have now developed world class facilities and knowledge of how to care for this species. This is a momentous achievement, as they can be extremely difficult to keep alive, let alone successfully breed.
At any one time we house between 400 and 500 stick insects in different purpose-built glasshouses and incubate thousands of eggs. A sample of eggs is measured and weighed in weekly batches and will then be incubated for between 6 to 9 months before hatching. Each nymph that hatches at Melbourne Zoo has a length measurement taken for our records. In 2013 Melbourne Zoo is breeding our 10th generation.
A number of scientific studies have been undertaken over the past 10 years, including investigating mate selection and parthenogenesis. Diet is an important aspect of animal husbandry and continual research and adjustments have taken place. 2013 sees the invertebrate department expand this work with investigations of plant species from Lord Howe Island both within Zoo grounds and on Lord Howe Island. All of this adds to the data base of important information on the species.
The Lord Howe Island stick insect is an integral species in Zoos Victoria’s “Fighting Extinction” campaign. In 2012 the Australian Federal Government and New South Wales State Government announced funding of AUS $9.2 million dollars to eradicate black rats from Lord Howe Island. It is hoped that this will restore the natural ecosystem of one of the world’s most beautiful heritage sites. One day we hope to see this species back in its natural environment on Lord Howe Island. The future of the Lord Howe Island stick insect now looks very bright indeed.
Wildscreen patron, Sir David Attenborough visited the Lord Howe Island Stick Insect at Melbourne Zoo in August, 2012.
Find out more about the Lord Howe Island stick insect and the work of Melbourne Zoo:
Rohan Cleave, Melbourne Zoo, Australia
The Lord Howe Island stick insect is one of the animals featured in ARKive’s new Conservation in Action campaign, which highlights a selection of species that are on the road to recovery thanks to the hard work and dedication of conservationists around the world.