A new generation of waterbirds has taken flight from nesting sites at Yanga National Park, near Balranald.
Hundreds of egrets, night herons and cormorants have completed their breeding cycles in the park. Environmental water created ideal conditions for the breeding event – a first for internationally recognised great egrets in the park since 2011. The NSW Office of Environment and Heritage (OEH) managed the event which saw close to 70,000 megalitres of Commonwealth environmental water and 4000 megalitres of OEH water delivered to the site.
OEH Senior Environmental Water Manager James Maguire said on-ground surveys led to the discovery of the rookeries.
A NPWS officer observed egrets carrying nesting materials across the park and follow-up aerial surveillance took us to them. Staff waded into the largest of the two rookeries and found 82 egret nests, 114 Nankeen night heron nests and 23 cormorant nests.
“The success of this bird breeding event is testament to the health of the Yanga wetlands system. With environmental water we have helped to sustain breeding conditions while the next generation of young waterbirds matured and took flight,” Mr Maguire said.
OEH environmental scientist Dr Joanne Ocock was part of the team that waded into the swamp to survey the rookery. She described the scene as ‘spectacular’.
“We waded through thigh-high water for about 500 metres before we came across the rookery. The spike rush was above our heads in places and the water so clear we could see the vegetation below the surface. The sound of birds twittering all around us was constant.
We heard honeyeaters, whistling kites, and willie wagtails and saw sea eagles – all brought to the area by this environmental watering event. As we neared the rookery we could see juvenile egrets, night herons and cormorants at various stages of development hopping and flying around their nests as their parents looked on. We kept our distance so as not to disturb the chicks while we counted the nests. It was an amazing sight, Dr Ocock said.
Commonwealth Environmental Water Holder David Papps said the timing and duration of environmental water was reviewed regularly and adjusted, based on monitoring and evaluation, as well as local knowledge.
“In this case, we were able to provide an additional 10,000 megalitres of water to support the bird breeding event based on information from surveys conducted by NSW Office of Environment and Heritage ecologists and our local engagement officer,” Mr Papps said.
Sites in the Lowbidgee floodplain are being monitored as part of the Commonwealth Environmental Water Holder’s new five-year $30 million Long-term Intervention Monitoring project (LTIM).
“Generating outcomes is not just about the science. It is about bringing people together to share information and build knowledge.” Mr Papps said.