Day 25, Goolwa to Goolwa

The aerial survey team today was Shelley Thompson from Murray-Darling Basin Authority, Kevin Lintern from South Australia’s Department of Environment and Water, Heath Dunstan from Victoria’s Game Management Authority, John Porter from NSW Department of Climate Change, Energy, the Environment and Water, Richard Kingsford from UNSW Sydney and pilot Tom Martin. We are constantly increasing the expertise of our observers.

Photo: Aerial survey team, Day 25.
Left to Right: Kevin, Shelley, Richard, Heath, John, Tom

Today we had to do two surveys of the Coorong, about 120 km north to south, and our second survey of the two lakes, Lakes Alexandrina and Albert. 

The morning involved flying down past the Murray Mouth and surveying waterbirds in the North and South Coorong. We took off from Goolwa and headed down the eastern shoreline of the Coorong, past the Murray Mouth.

Unlike in many previous years, we were not flat-out counting waterbirds today in the Coorong. The numbers were probably a tenth of what they can be during really dry periods across Australia. Annual patterns of waterbirds are intriguing with today’s patterns probably related to the floods in the Lake Eyre Basin.

Most of the waterbirds were teal, Grey Teal and Chestnut Teal.  There were also thousands of Black Swans, Australian Shelduck, Silver Gulls, Pelicans and cormorants. Various species of terns were also there in big numbers, it is difficult for us to tell them apart so we tend to group them. There were surprisingly few migratory shorebirds or resident waders like Avocets, no more than a few hundred. There was more water in the Coorong than in many previous years, meaning we had to fly further south to where the flooding stopped.

Video: There was sea spray on most of our Coorong videos but this video is of a large concentration of Black Swans (through the blurred lens). 

Contrasting the low numbers overall, there was probably a lot more breeding this year than we've seen in other years. Pelicans were breeding in their usual spot, but the rookery was large. There was also one tern and a couple of Silver Gull rookeries.

It took us around three hours to do the Murray Mouth and the Coorong and back again, because we did it twice, as we always do. We then headed back to Goolwa for our lunch break. 

Video: Taking off from Goolwa airport, over towards the sea to start our afternoon of surveying.

The afternoon was spent surveying the two big lakes, Lake Alexandrina and Lake Albert. We had previously counted them yesterday. They are massive expanses of water. Our survey technique is to follow the shoreline where the bulk of waterbirds will be.

There are always large hundreds of Great Cormorants, Pelicans, Black Swans and teal along the barrages separating the lakes from the Coorong. Most of the fish-eating birds are preying on the fish that go through the narrow flow channel between the two bodies of water. This is also where the seals were hanging out. 

We spent a bit of time getting photographs of the rookeries, potentially providing an archive for detailed counting of waterbird numbers in the future, given we can only provide estimates during aerial survey. These photographs have already proved useful in identifying some of the smaller numbers of species nesting among big flocks in the rookeries. 

Most of the time was spent following the extensive shorelines and peninsulas that mean the perimeter of the lakes is more than 100 km. Most of the waterbirds were fish-eating birds, the cormorants and Pelicans. There were also large numbers of Black Swans and Australian Shelduck. The other ducks, like Pacific Black Duck, Grey Teal and Australasian Shoveler were in small numbers. We only encountered one small flock of Pink-eared Ducks.

Video: Surveying a large flock of Pelicans and Great Cormorants

Straw-necked Ibis were nesting in more places than any other species, in about eight sites, sometimes several thousand nests. There were also nearly always small numbers of Australian White Ibis nesting.

Video: Surveying one of the Straw-necked Ibis rookeries, with the brown vegetation showing the nesting area.