Conservation

Filling the gaps in blue-wing shoveler knowledge

Working with Field & Game has sparked Alison Cash’s interest in waterfowl research

Zoology student Alison Cash has just spent a third year on the ground assisting with Field & Game Australia’s head and wing research, which has sparked an interest in waterfowl and the possibility of doing scientific research into the distribution and behaviour of the blue-wing shoveler.

The noted presence of blue-wing across south-east Australia during the opening weeks of Duck Season has drawn a lot of comment from hunters and many questions about why they were excluded from the bag in Victoria, South Australia and Tasmania in 2017.

Associate Professor Graham Hall, a leading figure in game management and particularly Australian waterfowl, has been asking himself the same question.

“If you know anything about blue-wing shovelers, you know that you can’t count them from the air because their preferred habitat is thick, vegetated swamps, so if you zoom over at 150 knots in an aircraft of course you are not going to count large numbers,” he said.

“That’s why hunters are confused, because they are on the ground, they are looking under the tree canopy, they are looking in the lignum swamps and they are seeing shovelers. Like them, I don’t doubt that there are plenty of shovelers about but the flawed way we try to count them indicates there are few around.”

In the early 2000s a PhD study into the shoveler’s diet and range was started in South Australia but it was abandoned before any meaningful data was gathered.

Assoc. Prof. Hall believes the time is right for a PhD candidate to take up shoveler research and he’s encouraged Alison Cash, a zoology student at the University of New England, to consider the opportunity.

“I think there’s a great study waiting to happen with shovelers: they are a big enough bird to put some satellite tags on them and find out where they are and where they are going,” he said.

“We’ve never done any survival studies on Australian ducks. You look at a lot of the North American studies, and they can tell you what the survival rate is from hatching to 30 days, which is where most of the mortality occurs, but we’ve never done that for Australian ducks.

“In the case of the shoveler, what is the survival rate, where are they nesting, is it in thick cumbungi and dead logs as Harry Frith said 30 years ago, do they move to nest and then disperse and how can we accurately monitor and count them?”

Nine years of data from head and wing samples collected by FGA members shows that even when shoveler is included in the bag, the take is very low.

“Hunters don’t take many at all: blackies, Wood duck, Grey teal, some year’s pinkies and some year’s hardheads would be the five main species taken. Chestnut teal, shovelers and Mountain ducks are the least common birds in the harvest,” Assoc. Prof. Hall said.

Alison is excited by the prospect of shoveler research primarily because so little is known.

“I’ve got a pretty strong interest in waterfowl generally, that is what has brought me back for the past three years to help with the head and wing research,” she said.

“As an active scientist, you want to pursue new knowledge and so something like the blue-wing shoveler, which has so little data gathered on it, is ripe for a research project.

“We know of the shoveler, but we know so little about it, so it is exciting as a scientist to chase that knowledge, learn about it and put that information out there.”

Alison said Field & Game members had a hunger for knowledge on ducks and could play a role in the research.

“The research could look at their travel patterns, where they are going and when and, just as importantly, where they are not going. You can learn so much just from getting data about their location in relation to life cycle, weather and prevailing habitat.

“What we know at the moment is observational; we have no hard and fast data to tell us exactly what is happening.”

Assoc. Prof. Hall said the FGA ground counts were very good but a lot more citizen science needed to take place, especially with a shift to an adaptive management model in Victoria.

He also cited the need for a seismic shift in human behaviour.

“In Australia the way we do wildlife management is unique: instead of all agencies and interest groups working to a common agenda to better manage the resource, we are so damn confrontational,” he said.

“How do we change that culture? Perhaps an adaptive management model will achieve that but in any model the parties have to accept a degree of risk because it involves an acceptance that you don’t always have perfect knowledge.

“At the moment we are saying without perfect knowledge we can’t do anything but under an adaptive management model you accept you will never have perfect knowledge and that there is an element of risk.”

An example would be to include blue-wing shoveler in the bag every year; understanding the dynamic wild population will fluctuate and so will the take.

“Some years that take will be high and other years low, but with data you can adapt to a point where you find the sustainable sweet spot and that might be a consistent bag of 10 birds per day with a limit of two shovelers,” he said.

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