New species find in Central Otago confirms link between Australian and South American shorebirds
A new species of shorebird, dating from a time when New Zealand was covered in subtropical forests and crocodiles roamed
parts of the South Island, has been found near St Bathans in Central Otago.
An international team of New Zealand and Australian-based scientists, including Canterbury Museum researchers, have
confirmed that the 19 - 16 million-year-old shorebird fossils belong to a group which had been thought to only comprise
the Australian Plains-wanderer and the South American seedsnipes.
The new species, Hakawai melvillei, has been named after New Zealand ornithologist David Melville to honour his efforts
in the conservation of migratory shorebirds.
Lead author and Canterbury Museum researcher, Dr Vanesa De Pietri, says that the team were excited to discover that the
fossil shorebird was not a typical wader, but more like an ancestral Plains-wanderer, with some seedsnipe-like features.
The Plains-wanderer and seedsnipes are unusual shorebirds as they have adapted well to living on the land.
“We’re happy to have found a fossil bird that provides a key morphological[1] link between the two groups. The discovery of Hakawai melvillei has confirmed our thinking that the ancestors of the
Plains-wanderer and seedsnipes were wading birds, like most other shorebirds,” she says. “It has also confirmed previous
research I’ve undertaken, with colleagues, that the Plains-wanderer and seedsnipes evolved their terrestrial habits
independently.”
The discovery sheds light on evolutionary processes at work when South America, Antarctica, Australia, and New Zealand
were part of the southern supercontinent of Gondwana. Hakawai melvillei, the Australian Plains-wanderer and the South
American seedsnipe are all thought to have originated in East Gondwana.
Canterbury Museum Senior Curator of Natural History and co-author of the study, Professor Paul Scofield says: “Hakawai
melvillei probably became endemic to (only occurring in) New Zealand when “Over millions of years, the Plains-wanderer
has efficiently adapted to a changing Australian landscape – from forests to sparse native grasslands. Unfortunately due
to the loss of its natural habitat, it is now one of Australia’s most endangered birds”, he adds.
Dr Trevor Worthy, a New Zealander working at Flinders University in South Australia who led the study, says “The
discovery of Hakawai melvillei adds to an emerging story of New Zealand’s role in the evolution of birds in the Southern
Hemisphere. Unfortunately, like crocodiles, turtles, and some tropical birds, which once inhabited New Zealand, the
lineage represented by Hakawai melvillei is long gone. We’re not sure what happened, but climatic and geographic changes
during that time may have been partly responsible for its demise”.
The team have published their research findings in the Journal of Systematic Palaeontology today.
ends