Posted
Pelicans and other waterbirds are dying in the
outback and disappearing from waterways, as the effects of drought
compound an already-concerning long-term decline in populations.
Key points:
- A dead pelican has been found a long way from water at an old railyard in South Australia's mid-north
- Pelicans can travel up to 3,500km in search of water, food and breeding grounds
- Waterbird numbers at Lake Eyre have been surprisingly low after an influx of water earlier this year
Truck driver Lisa Lloyd said she was surprised to see a dead pelican in a railyard at Quorn, 40 kilometres north-east of Port Augusta in South Australia.
"I was just wandering along on my horse and looked up and saw this great big black-and-white thing lying on the ground," she said.
"It's not something you see in Quorn."
The pelican had no visible injuries, Ms Lloyd said.
"He didn't look like he had been tortured, and the ground around him wasn't upset in any way — he just looked like he stretched out and died."
Outback pelicans
Greg Johnston, an honorary research associate with the South Australian Museum, said the bird appeared to be an adult in good health but was not in breeding condition.He suggested it might have been searching for water, adding that it was not unusual for pelicans to be spotted in the outback.
"Probably with the drought happening, particularly in the eastern states, there's not so much water around."Pelicans move extraordinary distances — they'll move up to 3,500 kilometres from a breeding colony, so you can find them anywhere."
Death, drought and Lake Eyre
Charter pilot Trevor Wright conducts daily flights over the Kati Thanda-Lake Eyre basin and said he wasn't surprised by lower numbers of pelicans and other waterbirds."Compared to previous years, there was definitely a decrease in the population of banded stilts," he said.
"There were a few flocks of pelicans around, but I think because of the drought the bird populations in general are down.
"The Australian continent definitely needs an increase in the amount of rainfall just to get the environment as a whole and the birdlife back to a sustainable level.
"Hopefully we'll get some drought-breaking rain over the summer period to bring the populations back."Professor Johnston said pelicans often flew to Lake Eyre following an influx of water, but flooding that occurred earlier this year was not enough.
"Usually there has to be water from flows down the rivers from the northern monsoons topped up by local rainfall, and we just haven't had the rainfall to expect that kind of breeding event."
Possible extinctions
Professor Richard Kingsford, director of the Centre for Ecosystem Science at the University of NSW, conducts annual bird surveys across the Lake Eyre basin, the eastern seaboard and the Murray-Darling basin.He said the Murray-Darling system drying up was another major reason why waterbird populations across the country were falling.
"There's been around about a 70 per cent decline [in waterbirds] over the past 30-odd years."Those sorts of changes would obviously have big impacts given how important the Murray-Darling is both for the Lake Eyre basin and other places in Australia."
Professor Kingsford's next survey of Lake Eyre is in October, but he is already receiving information from locals saying the number of waterbirds is surprisingly low.
"In previous years we've seen an erratic number of waterbirds because they essentially arrive when the big floods come along, and then there's hardly any when those systems dry out," he said.
"It's a sort of silent wave of deaths that occurs during these very dry times."
Pelicans are not the only birds whose populations are suffering, Professor Johnston said.
"Eastern Australian bird counts that are done by the NSW, SA, Victoria and Queensland governments every year, for nearly 40 years, they're actually showing a very consistent decline in the number of ducks, pelicans, cormorants and other waterbirds," he said.
"They're showing us that our wetlands and our river systems are declining in quality over the long term.
"If the decline continues, if we don't get our management of water in Australia sorted out, we're going to see those declines continue and the ultimate result of that is extinction of animals."
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