What's on: AMRI Seminar Series
The Australian Museum Research Institute hosts a monthly series of short talks showcasing current research at the Australian Museum.
- Event Type:
- Special event
- 01.00 PM to 02.00 PM
The seminars consists of snapshots of new results or ongoing projects designed to keep our staff informed, but are also open to members of the public with an interest in scientific research.
Wedensday 18 April 2018
A research trip documenting outrigger canoes from the Massim region in Papua New Guinea
David Payne, Australian National Maritime Museum
In August 2017, David Payne, the Historic Vessels Curator at the Australian National Maritime Museum, undertook a month long voyage by boat amongst the remote and inspiring islands off the east coast of PNG to document the outrigger canoes of the Massim region. The team, including Dr Harry Beran (a world renowned authority on Massim culture and art), explored the Louisiade Archipelago before following a route similar to the Trobriand Kula Ring Cycle amongst the islands in the Solomon Sea to the north east of Milne Bay. Over 30 islands were visited in under 28 days. The results were spectacular. Examples of all the key current and traditional craft were found and measured accurately, war canoes were documented, small fishing canoes recorded, and the symbolism of the carving and decoration was explained. David is now working on his speciality, preparing accurate plans of these amazing craft, some of which have not been documented extensively until now.
Emerging Eucalyptus dieback caused by a previously unknown psyllid species
Associate Professor Markus Riegler, Hawkesbury Institute for the Environment, Western Sydney University
Eucalypts are associated with diverse communities of native psyllids. Many of these psyllid species are rare and hardly noticeable; some, however, can experience rapid population build-up and cause significant area-wide eucalypt defoliation and dieback. Over the last decade we have documented unprecedented area-wide defoliation and dieback of two dominant Eucalyptus species over several thousand hectares of the critically endangered Cumberland Plain Woodlands in Sydney. This was caused by two outbreak waves of a potentially new psyllid species, grey box Cardiaspina sp. (Hemiptera: Psylloidea: Aphalaridae) that specifically feeds on grey box (Eucalyptus moluccana), and another outbreak by Cardiaspina fiscella on Eucalyptus tereticornis. Our data demonstrate that the psyllid populations experienced boom and bust cycles that were impacted by resource availability and climatic factors, and were abruptly stopped by summer heat waves that crashed psyllid populations. Psyllids were attacked by diverse parasitoids, however natural control of psyllids by natural enemies was limited during the outbreaks. Given the new emergence of a defoliating Cardiaspina sp. on E. moluccana, an important Eucalyptus species in woodlands across eastern Australia, the genetic identity of grey box Cardiaspina sp. and its host association became a major point of inquiry. Genetic analyses of the psyllid species and its associated maternally inherited bacterial symbionts demonstrated that it is distinct from its relatives that are specific to other Eucalyptus species in other parts of Australia. It is also associated with a distinct parasitoid community. In a common garden experiment with different Eucalyptus species we found that grey box Cardiaspina sp. is highly specific to E. moluccana provenances from Sydney and beyond, from New South Wales and Queensland. This highlights the potential risk for grey box Cardiaspina sp. to become far more widespread, similar to the notorious Eucalyptus defoliator C. fiscella that is widespread in Australia and invasive in New Zealand. Our research highlights that endemic herbivorous insects can become a major problem in critically endangered ecological communities and can constitute an additional threatening factor.