Climate change leaving koalas high and dry
Koala handlers have been telling zoo visitors for years that koalas get all the water they need from eucalyptus leaves – but increasingly, those leaves may no longer hold enough water to keep them alive, as climate change triggers long droughts and intense heatwaves.
University of Sydney researchers have used video surveillance to show koalas hunting for water in drought-ravaged eucalypt forests – and there are signs this behaviour will continue.
The Australian Koala Foundation estimates that the national wild koala population could be less than 80,000, compared to the millions that existed during the early part of the 20th century. Many factors contribute to their vulnerable state including dog attacks, diseases like chlamydia, accidents with vehicles and loss and destruction of habitat, which is one of the larger attributes.
Meteorologists have said that the drought currently covering much of eastern Australia is the worst that has occurred in 400 years. These conditions affect koala habitats by drying out the eucalyptus leaves, forcing the native animals to change their water collecting behaviours.
“We used to have only three to four days above 30 degrees, now they last seven to eight days,” says Angela Baker from the North West Local Land Services in Gunnedah, who is also associated with the Gunnedah Koala Conservation Plan.
Dr Valentina Mella, a researcher from the University of Sydney, has investigated the role of climate change on gum leaves and found that koalas reject the foliage when the leaves have a water content of less than 55% to 65%.
She’s collected photographic evidence of koalas leaving their trees in search of new water sources including puddles, dams and even birdbaths.
Concerned, Mella approached Robert Frend, a farmer from Gunnedah.
Gunnedah’s tourism marketers call the town ‘the koala capital of the world,’ and locals boast it was the only town able to increase its koala population in NSW through numerous tree-planting campaigns. Yet 25 per cent of the town’s koala population was still eradicated by a heat wave in 2009.
Inspired by the need to provide a more reliable water source for thirsty koalas, Frend tapped into his machinery and welding capabilities, stepped out of his comfort zone and came up with a solution.
Frend has invented artificial water stations or “Blinky Drinkers” (named after the iconic Australian children’s character “Blinky Bill”) to be placed on trees for the koalas to access.
Frend’s invention was soon shown to be just what the koalas needed, as more video surveillance recorded the marsupials, day and night, spending an average of more than 10 minutes drinking from the blinky drinkers.
There are currently 26 drinkers on several private properties, containing 220 litres of water each, catering for around 1000 koalas. They all can go three months without being refilled, but need a maintenance check on the pumps every three weeks to make sure everything is running smoothly.
Dr Mella and Frend are expanding and modifying the Water for Koalas project by accessing other koala forests in Queensland and Victoria, placing the ‘Blinky Drinkers’ higher up in trees to prevent predators from accessing them, and developing the device to a point where it can be refilled just three to four times a year.
While the project is saving koala’s lives, there’s plenty of questions around its rationale.
Artificial water stations result from human intervention that doesn’t involve the rehabilitation of the natural environment and is overall indirect.
Some critics question whether these blinky drinkers could be causing a negative impact previously not considered, like creating a dependence on direct human action.
For Mella, the blinky drinkers are creating a positive impact and do not make the koalas too dependent, because there is nowhere else in the environment for the koalas to access water.
Koala behaviours revolve around survival. When locating water, their thought process is, “There’s water there, let’s access it”. Without the drinkers, koalas might use the swimming pools or cattle troughs around the area.
Robert Frend not only agrees but also says that “there isn’t a choice” when it comes to human intervention. For him, those who condemn it are “short-sighted and selfish” with “immature attitudes”. He says that preserving biodiversity requires human intervention.
Angela Baker also agrees that human intervention is necessary. She views it as a responsibility because humans have already intervened – for example by introducing feral animals.
One of the main reasons native species are unable to survive in their own natural habitat is because humans have modified the landscape so much.
Baker says that since humans have already intervened, we might as well intervene in a positive way.
Blinky drinkers add to a growing list of positive direct human interventions, including the Hume Highway rope bridges called “glider poles”, created to help the sugar glider population.
The freeway acted as an obstacle to glider movement, so the poles were invented to help the animals cross safely and gain access to originally cut-off loved-ones, shelter and food. Through motion-triggered night cameras, genetic testing and microchipping, around 400 gliders were recorded using the bridges between 2005 and 2015.
Whether or not the blinky drinkers are a long-term solution, or direct human intervention is what needs to be done is questionable. However, there’s common consensus that they are a great solution for the current drought situation and for upcoming summer heatwaves.