World-first Monash study shows bird flight paths through two proposed Bass Strait wind farms 

JJ Harrison

A world-first study of birds migrating across Bass Strait has shown they travelled directly through zones earmarked for the federal government’s two declared offshore wind farms.

Monash University researchers studying Tasmanian Boobook owls have become the first to examine flight migration paths from Victoria to Tasmania, tracking the birds via satellite to map their over-water journeys.

The findings, published today in the peer-reviewed journal Emu – Austral Ornithology, highlight the importance of Bass Strait as a flyway for land birds and raise a potential environmental threat posed by the Federal Government’s 21,100km² declared offshore wind areas off Gippsland and Northern Tasmania.

Monash Associate Professor Rohan Clarke said it’s a reminder that development of renewable energy infrastructure should be informed by ecological research to mitigate the impacts on local wildlife.

“As ecologists, we recognise more than most the urgent need for the renewable energy transition to address the immediate threat of climate change,” Professor Clarke said.

“But this can result in what is known as the green-green dilemma; a conflict that arises when industrial transformation aimed at environmental sustainability causes harm to other environmental or ecological priorities.

“It’s crucial that conservation and biodiversity experts work closely with those delivering the renewable energy transition to avoid unintended consequences for our wildlife.”

While millions of Australian land birds migrate annually, the phenomena in Australia is poorly understood.

Professor Clarke said this means there are knowledge gaps that must be addressed when considering renewable energy projects such as wind farms.

“Bass Strait is one such area, where large numbers of birds fly between Tasmania and mainland Australia, flying north in autumn and returning south in spring – yet the flyway is considerably understudied,” he said.

“This highlights the need to fully understand and carefully manage the effects of development on wildlife, which requires better understanding of bird movement in important flyways.

“Our research is critical to inform these issues so that policymakers, developers and land managers can act accordingly.”

To undertake the research, Monash researchers attached tiny tracking tags to Tasmanian Boobook owls captured on the coastal headland at Cape Liptrap in Victoria’s South Gippsland.

These tags, taped to several tail feathers in a method that ensures tags fall off without harm soon after the battery goes flat, record the GPS position of the bird.

All tracked birds that made the trip south did so in a non-stop, overnight journey, passing directly through the declared priority area for offshore wind to the south of Wilson’s Promontory.

The data captured in the Monash study was supplemented by thousands of citizen-scientist entries on online database, eBird.

Jessica Zhou, a Monash ecologist and co-author of the study, said the research provides crucial, new knowledge for a key migratory bird flyway that faces growing pressures from development and resource extraction.