"The Situation is Dire: Rabbit Populations on Phillip Island Are Ballooning to Alarming Levels!"
Every day, Peter Bradley and his wife, Vicki, undertake a thorough examination of their property, searching for the latest signs of destruction caused by rabbits burrowing beneath their home’s foundation.
"It's causing a lot of anxiety around here," Peter, a resident of the Bass Coast, expresses.
"Each time I repair the damage, those pesky rabbits seem to come back for more. If I leave any holes, the situation just escalates."
This routine of cleaning up scattered mulch and wire, as well as filling in holes, has turned into a grim daily chore that many locals share in the stunning coastal area southeast of Melbourne, where rabbit populations have swelled to what many refer to as plague proportions.
Harold Jackson, who has made Phillip Island his home for 27 years, notes that this year has brought unprecedented rabbit troubles. The extensive damage to his garden in Cowes, the island’s central township, has incurred costs approaching $20,000.
"It's a relentless issue," he remarks. "They dig holes everywhere... they constantly uproot my roses and attack their roots."
In a push to find a solution, the Bass Coast Shire Council recently voted unanimously to formulate a new rabbit eradication plan, acknowledging that years of attempted control—spanning 15 years and costing $180,000—have not yielded effective results.
The dramatic rise in rabbit numbers along the coast could be attributed to certain environmental conditions that hinder Australia's biological control efforts, suggests rabbit specialist Dr. Brian Cooke. With nearly six decades of research under his belt, Dr. Cooke has been part of successful eradication initiatives, such as the one on Macquarie Island. He posits that a harmless virus known as RCV-A1 might be shielding these rabbits from Australia's primary biological weapon—calicivirus.
"These non-threatening viruses tend to circulate mainly in coastal regions, particularly in areas with significant rainfall, and they are less present in Australia’s drier inland zones," explains Cooke, who serves as the patron of Rabbit Free Australia.
He further elaborates that the RCV-A1 virus grants cross-immunity, meaning rabbits that contract this benign virus develop immunity to the fatal rabbit hemorrhagic disease virus (RHDV), commonly referred to as calicivirus, which has been a key control method since 1995. In coastal settings where lush greenery is available year-round, these rabbits encounter RCV-A1 more frequently, thus ensuring their survival and propagation.
Dr. Tanja Strive, a senior principal research scientist at CSIRO who has extensively studied RCV-A1, notes that laboratory tests reveal "some cross-protection" against calicivirus in rabbits that had previously been exposed to this harmless variant; it has long been recognized that control efforts are less successful in coastal regions.
"When calicivirus escaped from Wardang Island and spread, it decimated over 90% of rabbit populations nationwide, with the exception of some more temperate areas, including coastal zones," she states.
The Bass Coast’s unique blend of natural coastal elements and suburban expansion can generate what Strive describes as an "upward spiral" of rabbit immunity. "In regions close to the coast, we encounter increased rainfall, and in peri-urban landscapes, we create food sources through irrigation that further boost the rabbit population," she explains. "Once their numbers swell, it intensifies the spread of this harmless virus, which in turn enhances their immunity even more."
"Rabbits Are Undermining Our Way of Life!"
For Carola Adolf, who has resided on her Bass property for 35 years, the explosion of rabbit numbers has turned her everyday life into a perilous endeavor. While mowing her land, her ride-on mower unexpectedly fell into a concealed rabbit hole, resulting in serious injuries that left her biting her tongue and bleeding profusely.
Her property, once a haven for horse riding instruction, can no longer be safely maintained, as her horses face a constant risk of severe leg injuries from stepping into the numerous burrows. "They can weigh up to 500 kg, and if they step into one of these, it could break their leg," she points out, indicating the burrows surrounding the horse shed.
At night, she witnesses hundreds of rabbits crossing the roads.
"When I return home after dark, the entire road appears to be moving. It's frightening," she explains. "They undermine everything, including fences and even the root systems of trees."
Addressing this urgent problem demands interconnected efforts across various government entities, which has proven challenging thus far.
"We're eagerly seeking innovative solutions because our previous attempts have largely fallen flat," says Mat Morgan, a councilor who supported the motion to devise a new eradication plan for the Bass Coast Shire. "This is not an issue that local government can tackle alone. We have DEECA [the Victorian Department of Energy, Environment, and Climate Action] managing substantial beach areas, Phillip Island Nature Parks overseeing the penguin parade and several other ecological assets, and the council responsible for managing other regions. We're collaborating with multiple land management entities."
The 27-year-old councilor explains that he has spent the past year observing bureaucrats working in isolation across various levels of government, each department seemingly "reinventing the wheel" instead of coming together to find effective solutions.
Jack Harris, who coordinates the rabbit project for the Bass Coast Landcare Network, notes that rabbit management practices vary significantly among landholders.
"You might find one landholder doing an excellent job controlling rabbits, while another is completely indifferent. Consequently, you end up with a patchwork of properties: some areas free from rabbits and others overrun. As a result, you can never fully gain control of the situation," he asserts.
Compounding this issue is community apprehension towards standard and effective anti-rabbit methods, such as baiting, as Cooke notes. "Some individuals worry that their dogs may be poisoned through these measures."
Furthermore, the need to shield the endangered eastern barred bandicoots—reintroduced to Phillip Island after being declared extinct on mainland Australia—adds another layer of complexity to control measures. In regions occupied by the bandicoots, baiting cannot be utilized.
Yet Cooke warns that a burgeoning rabbit population has broader ecological consequences, such as facilitating a higher number of feral predators like foxes and cats, which prey on native wildlife, in addition to causing severe damage to indigenous vegetation.
Morgan adds that the invasive pests are compromising the region's environmental reputation. "Bass Coast and Phillip Island have a genuine chance to become a sanctuary for endangered wildlife," he asserts.
"We have numerous endangered species that have been brought to Phillip Island as a safe haven. If we could further promote biodiversity by managing rabbit populations, it would present an extraordinary opportunity."
In the meantime, the council is tasked with compiling a report on potential eradication strategies.
Cooke observes that Australia has also lost vital knowledge regarding rabbit control, primarily because biological control measures were so successful for so many years that "very few individuals under the age of 50 have genuinely experienced high rabbit numbers."
"The majority of the population lacks a clear understanding of the havoc that rabbits can wreak when their numbers soar," Cooke adds. "People need to shift their perception of rabbits from being just cute characters from Beatrix Potter stories to recognizing them as a serious ecological problem."
He emphasizes, "It is crucial to initiate eradication efforts without delay. It’s always better to act now rather than wait five years and face double the problem and double the expenses."
