The Star Mountains, located in southwest Papua New Guinea, are rich in botanical species: during February and March this year, the intrepid research team identified around 700 plant varieties, of which 28 were new species, including rhododendrons, myrtles and orchids (there are more species of orchid in New Guinea than any other region). There were also a number of pitcher plants: these carnivorous plants sprout specialised leaves that unfurl into jar-like traps, the waxy inner surfaces of which secrete a viscous liquid; unfortunate insects – and occasionally frogs, lizards and other vertebrates – fall into these traps, drown, and decompose, enabling their decaying bodies to release nutrients that are absorbed by the plant. One new plant species belonged to the Genus Plectranthus: more commonly known as spur-flowers, these organisms are often grown by indigenous societies for their edible leaves and roots, as well as for their medicinal properties and visual beauty as ornamental specimens.
To monitor large vertebrates, the biologists used traditional ecological fieldwork techniques as well as camera-traps for observing mammals, including large rat-like rodents, some of which appeared to be the size of a small dog. An expert on birds, Iain Woxvold observed a number of species, including the sooty shrikethrush, Queen Carola’s Parotia bird-of-paradise, mountain kingfisher, feline owlet nightjar, the Papuan longrunner, Meyer’s goshawk, and the Papuan eagle. The dwarf cassowary – a large flightless bird, famed for its territorial temperament and long claws that can disembowel a human – was also observed, yet only in some areas partly due to local hunting pressures and egg collection. Although no new bird species were encountered, there were regular recordings of MacGregor’s bowerbird. The polygamous males of this speciesconstruct tall, tower-like maypole structures, assembled with a central column of twigs, decorated with flowers, fruit and insects, and encircled by a disc of moss with raised edges, roughly a metre in diameter; when a female inspects the structure, the male struts, calls, and flares his orange-yellow crest to entice her to mate.
Leeanne Alonso, Director of Global Biodiversity Exploration at Global Wildlife Conservation, specialises in ant biology. Ants, together with bees and wasps, encompass an order of insects known as the Hymenoptera (next time you see a flying ant, note its anatomical resemblance to a wasp), and many representatives of this group exhibit complex hierarchal societies. The founder of an ant community is the queen. Young queen ants usually mate during the early flying-phase of their adult lives, and store sperm in specialised seminal receptacles (after mating, the winged males die). Once sperm has been collected, the queen detaches her wings and begins to excavate a small burrow to lay the first of potentially thousands of eggs. The queen can determine the gender of the eggs she produces, resulting in many generations of infertile females that populate and maintain the colony. Queen ants cannot live alone: many other members of the society, including nurses, guards and thousands of workers cooperate to enable the colony’s survival.
Numerous ant species can be found in tropical forest ecosystems. At Camp One, situated in cooler climes at a high altitude, Alonso and local Papua New Guinean researchers, including Wallace Takendu and Alois Gambia, used bush-knives to pull apart decomposing logs on the forest floor to expose ant nests. In the lowlands around Tabubil, the ants were more active due to the warmer conditions and could be monitored as they energetically scurried through the undergrowth, searching for morsels of food. The team also employed the Winkler method for collecting ants. This process involves sifting leaf litter with a standard kitchen sieve; the sifted contents are subsequently hung in mesh bags for 48 hours. Disturbed ants within the bag are soon active; careless individuals tumble through the mesh and into a volume of ethanol located at the base of the bag, enabling identification. This practice is useful for collecting very small ant species that live deep within layers of decomposing leaves and organic matter, and which often escape observation. After the ants had been collected, they were sent to the laboratory of Dr Andrea Lucky at the University of Florida, where they will be identified by entomology students.
Many other insects were catalogued, including 180 butterflies and at least 8 new damselflies (these insects differ from their relations, the dragonflies, by landing with their wings held together above the abdomens; dragonflies land with their wings outstretched) that are new to science. A number of beetles were also collected, including ambrosia beetles. These organisms live in recently deceased trees, where they excavate burrows through what was once the xylem, or water-conducting tissue, to release spores of ambrosia fungus. It is from the fungus that the beetles derive all their sustenance. Due to the inconspicuous lifestyle of these insects, they can be difficult to document. However, they are attracted to ethanol, and can be lured to the collection site by inverting soft drink bottles and suspending them from the bough of a tree. The bottles have small windows cut into their flanks and are filled with ethanol. Enticed by the alcoholic scent, the beetles fly through the windows and into the liquid, where they will be preserved for identification by Dr Jiri Hulcr, a leading authority on ambrosia beetles at the University of Florida.
A joy in any tropical forest comes from the humming, buzzing, hissing and screeching sounds made by the insect community, and of this ensemble the grasshoppers and crickets are among the most musical. Differentiated from grasshoppers by elongated antennae that stretch further than the length of the body, male bush crickets, also known as katydids, use a groove-like edge on one of their wings to rub against the complimentary wing to generate sound for attracting females. An abundance of bush crickets were observed by the team, which were collected at night while on expeditions in search of amphibians, reptiles and mammals. Additionally, an ultraviolet lamp was set up at Camp One to attract nocturnal flying insects including bush crickets, which were collected for classification by Dr Piotr Naskrecki – an expert on grasshoppers and katydids – from Harvard University.
These new findings are of great importance to biologists and for Papua New Guinean conservation. Reasons for this include: assessing the conservation status of the Star Mountains’ region; providing valuable data for the government to assist with environmental policy and planning; evaluating the ecological resources of Papua New Guinea; presenting baselines for monitoring endangered species; and identifying possibilities for ecotourism. After just four weeks of surveying, the outcomes also indicate a need for further studies to provide a greater understanding of the complex ecological communities that such an environment supports, and the medicinal properties that may derive from the newly described plant species. Camp One is only 32 kilometres from the Ok Tedi Copper Mine; even so, the forest surrounding this area had a rich biodiversity and supported many new species. Around the mine and the settlement of Tabubil, which has grown significantly since the late-1990s, the impacts of human development are more apparent. Areas of forest have been cleared to enable gardening and the soil is contaminated around the mine itself. The Ok Tedi mine is beginning to explore other areas in the Star Mountains range, in search of further gold and copper deposits, which could threaten the forest ecosystem. Until recently, human communities in this region have managed to live without disturbing large areas of forest by sustainably managing the area, and only using certain trails that join villages. Yet there is now a large people migration to Tabubil from outside Western province. This increased development combined with the impacts of open-pit mineral mining pose a threat to the forest’s diversity and the valuable ecosystem services that such habitats provide.
The research also aims to showcase the spectacular Hindenburg Wall and the greater Star Mountains’ area, and help support the region’s current nomination for UNESCO World Heritage status. Rich in fossil remains and extensive cave networks, the glacier-sculpted limestone and shale Hindenburg Wall formations, together with the virtually uninhabited Muller Range, and the Nakanai Mountains, volcanoes and underground rivers on the Papua New Guinean island of New Britain, are all under group consideration for the Sublime Karsts of Papua New Guinea UNESCO World Heritage Site. Such international recognition and protection of these three sites, which were surveyed by Alanso and Conservation International’s Rapid Assessment Programme in 2009, will help preserve these areas of outstanding natural beauty and scientific interest, and the organisms that thrive in such terrains.
Undoubtedly, this study reveals the great splendour of the natural world, which still exists relatively unharmed from the presence of humans in one of our planet’s last great wildernesses: surely a region that should be cherished and protected for future generations.
By Jonathan Booth