Irreplaceable - Murray-Sunset, Hattah & Annuello, Australia
In our 'Irreplaceable' series, we cast a light on the globally-significant bird habitats that are in danger of disappearing forever.
Stretching across three national parks and covering 7,004 km2 of semi-arid shrubland in North-Western Victoria, this area is one of the last refuges for a number of endangered bird species dependent on its unique mallee habitat for survival.
Mallee is a term used to describe species of eucalypt plant that have adapted to survive in hot, dry areas prone to bushfires. They boast a swollen root crown laced with buds. When the plant is destroyed by fire, the dormant buds allow it to grow back in multi-stemmed form. After 15-20 years of unburnt growth, they offer the perfect environment to deliver sanctuary and shelter to several specialist species.
These include Malleefowl Leipoa ocellata, a chicken-sized megapode once widespread across Australia, but now restricted to scattered locations across southern Australia. Other resident species are scarcer still. A small colony of 20-40 breeding pairs of Black-eared Miner Manorina melanotis in Murray-Sunset National Park is considered one of only two populations deemed pure enough to be worth conserving, due to frequent interbreeding with Yellow-throated Miner Manorina flavigula. Also restricted to a handful of populations in Victoria, Mallee Emuwren Stipiturus mallee is more numerous within this Important Bird & Biodiversity Area (IBA), with an estimated 200 breeding pairs, but its numbers are plummeting fast.
For all these species, the biggest threat to their future is destruction of mallee habitat from further fires, both unplanned and planned. Victoria’s government currently adopts a policy of planned burning of 5% of public land ever year, an initiative intended to minimise the risk of human life from bushfires. However, since species such as Mallee Emuwren are poor flyers, these firebreaks further isolate their populations, as they’re unable to travel over the burnt heath.
Modelling indicates that due to the time it takes for the mallee vegetation to grow back, this policy will render this IBA uninhabitable for these species within 20 years. BirdLife Australia is calling on the Victorian government to ensure the needs of threatened species are incorporated into their fire management planning, drawing up the Threatened Malee Birds Conservation Action Plan which also advocates strategic revegetation programs to combat habitat fragmentation, and re-establishing populations in areas within the reserve which now have suitable habitat. Without these measures, these species could be just one blaze away from disaster.