World's largest butterfly faces extinction due to palm oil industry
30 September 2017
SUBHOJIT GOSWAMI | Down to Earth | Edited
NEW DELHI - It is perhaps because of their beauty and grace that they were named after the wife of Edward VII.
Queen Alexandra’s Birdwing, the largest butterfly in the world with a wingspan of 30cm—at least 10 times the size of common butterflies—was discovered in Papua New Guinea in 1906.
More than a century later, one of the world’s rarest species has become the most endangered. In Oro Province, its last frontier, the density of this butterfly has shrunk to only 10 per square kilometre. They are now handful in number, but what’s causing the species to dwindle?
PNG has an ideal climate for palm production and the industry is fast expanding.
With traditional locations for plantations running out, companies are turning to clearing unexploited tropical forests - natural habitat of the birdwing butterfly.
Not only are trees being cut indiscriminately, the areas earmarked for palm oil production are set on fire as a preferred method of clearing. The extent of damage done in the tropical rainforest is evident in satellite images.
There have also been reports about government losing control over palm plantations, which are being increasingly privatised, with Chinese, Malaysian and Indonesian investors appropriating land to increase the network of oil palm plantations.
The same region, whose landscape is undergoing a rapid change, is home to three out of the top 10 endangered species of shallowtail and birdwing butterflies.
While Queen Alexandra's birdwing is considered endangered, Papilio moerneri is one of the rarest and least known of all PNG swallowtail butterflies and it has not been seen since 1924. The Southern Tailed Birdwing is also considered vulnerable.
Habitat alteration due to volcanic eruption in the 1950s and habitat destruction for oil palm plantations are key reasons why they are pushed to the brink of extinction.
Fortunately, a new initiative is coming to the rescue of these beautiful creatures. The Swallowtail and Birdwing Butterfly Trust (SBBT), led by entomologists and conservationists, has been established to conserve and protect butterflies of the Papilionidae family globally. Its first project is Queen Alexandra’s Birdwing.
With funding from the Malaysia-based Sime Darby Foundation), SBBT is trying to create a state-of-the-art captive breeding and release facility in New Britain Palm Oil Limited’s Higaturu palm oil estate—the heart of the butterfly’s home.
The captive breeding and release programme will be accompanied by habitat enrichment and protection of remaining forest areas around oil palm plantations.
“Sustainable conservation requires high quality, practical, on-the-ground conservation, with local communities and business working in partnership,” says Mark Collins, chairman of SBBT.
SBBT is providing technical, scientific and international support for studying the best areas to release the butterflies in the forests surrounding the palm oil estates, cultivating vines in those areas, and making sure there are supplies of the butterflies' favourite food plant, the Dutchman’s pipe.
Where I come from in Queensland the exotic vine Dutchman's Pipe (Aristolochia littoralis syn A elegans) is related to the native vine, but creates a further danger for the Richmond Birdwing.
The exotic vine smells exactly the same as its native food plant, so they lay their eggs on it and when the caterpillars hatch and eat its leaf, they die.
This is one of the reasons why the Richmond Birdwing Butterfly is endangered (information from the internet).
I suspect the same goes for Oro and the QABB that we commonly referred to as the Popondetta Birdwing when I was posted there 1969 to 1973.
Posted by: Doug Robbins | 30 September 2017 at 10:49 AM