A number of Menindee locals and tourists have expressed concern that they are not seeing the number and variety of species of birds they would expect to at this time of year.
Local Bird photographer Geoff Looney said that from his observation certain bird species are either not visiting Menindee or continuing on their journeys quicker than in previous years.
“Of the 208 species I have recorded, there would be lucky to be 60 left in Menindee, they are not appearing.”
“Even the millennium drought still left some water in the system, since then the whole system has been dried out,”
“There must be something interrupted in the food chain, I have been here 4o years and never seen so few birds.”
Mr Looney said that in particular, he had not seen any migratory species.
“That could be because there is so much water and they are somewhere else, but usually I would see a sprinkling of overseas wader birds somewhere.
“Of the fourteen species that have visited Menindee and I haven’t seen any of these the last two years, “he said.
“I saw one black-shouldered kite 3 weeks ago, but I haven’t seen it since, so it hasn’t hung around, which is not good.”
“I’m not saying they never came here, but they never stayed here.”
Senior Scientist Ecosystems and Threatened Species, Department of Planning and Environment, Dr John Porter who helps coordinate the Annual Aerial Survey of Wetland Birds in Eastern
Australia through UNSW Sydney said that from the aerial survey there was actually a slight increase in the number of birds compared to last year.
“It’s all about what is going on in the landscape and if there are 100 times more habitats than there was yesterday with the same number of birds.
“There is going to look like a lot less because you can’t see where they are as they are spread out by a factor of 100.”
Dr Porter said that when there is a drought happening and the lakes are much lower there are not many areas for birds to go and the remaining birds will aggregate in small areas.
“When you have a huge smorgasbord of places to go they are all spread out and as happy as can be; you just can’t see them as easily, “he said.
“Tourist operators in the Northern territory will tell you that the time to see birds is not in the wet season, it’s in the dry season when they are all concentrated. “
Dr Porter said that if there was some sort of issue in the food chain or water quality, you would expect to find dead birds.
“I don’t think there is any evidence of that. “
Mr Porter said that from the monitoring conducted through the aerial surveys, there was a lot of evidence of breeding that is happening this year.
“There are a really big number of large water bird breeding events, including pelicans in NSW on Lake Brewster and on the Lower Murrumbidgee,” he said.
“Colonies of more than 10,000 birds, there are some big Ibis breeding rookeries in the Macquarie Marshes, Gwydir and other wetland areas in the Lower Murrumbidgee.”
All the evidence is saying the birds are recovering; they are spread out a bit, but doing well while the conditions allow.”
Allan Raine, Director, Water Planning Implementation (DPIE) said that From the monitoring network that DPIE coordinate in partnership with WaterNSW, they are seeing that water quality is nutrient-rich with an increase in phosphorous, nitrogen and carbon levels.
“Phytoplankton feed on the dissolved organic carbon, that’s fed on by zooplankton; they are the kind of things that drive the food chain. All of those things are in place.”
Mr Raine said successful fish breeding events were evidence that there are plenty of food resources in Menindee.
“There are lots of fish fingerlings it’s not a lack of food or a poor water quality issue, it’s just that there are an abundance of food resources everywhere. “
Mr Raine said that the biggest issues that DPIE have seen so far have been the Hypoxic Blackwater and Blue-Green algae.
“Fortunately there has been enough water around that it has not caused any major fish deaths and it doesn’t impact on the water birds.”
Mr Raine said that there should be a drop in Blue-green algae as we approach winter and the temperature drops.
“Blue-green algae has an adaptation where they can control where they sit in the water column, so in situations like we have at the moment where the water is highly turbid, they have an ecological
advantage over other species in that they can control their buoyancy and can basically float to the top, and continue to photosynthesize.
“Other algae species that you find in the water column can’t do that so they don’t survive under turbid conditions.”
Dr Porter said that it is common for the extent and quality of the habitat, to change with the water as it waxes and wanes.
“The birds will move to find what they need,” he said.
“When the water is really deep, it is a preferred habitat for fish-eating birds and some of the diving ducks and egrets, things like pelicans and cormorants and darters. Other birds like ducks and whooper swans that like more shallow feeding areas will have moved away to find more shallow water. “
Mr Looney said that while there are many species he has recorded seeing in his years photographing birds at Menindee, the obvious birds he feels are missing in the last year are large groups of birds.
“Large blocks of pelicans, hundreds of avocets thousands of ducks they are just not being seen.”
“Admittedly the lake system is full and there is more water to spread out but you are usually seeing something,” he said.
“I am not an expert but all I can say is what I see”
