Short-tailed Shearwaters (most frequently known as Mutton Birds) are with us from late September through to mid April / early May. You may also have heard them referred to as Moonbirds, or Yolla, an Aboriginal name for Shearwater.
They’re an unassuming looking bird, with short tails and smoky brown plumage, they weigh, on average, 550g but they have an impressive wingspan of 1 metre. They can fly up at up to 85km/h and dive as far as 50m, using their wings to “shear” through the waters surface, and then propel them through it.
Every year, each bird will travel over 30,000 kms on a round trip that includes Antarctica, New Zealand, Siberia, South America and Japan. Predominantly, they live at sea, only returning to land to breed. Mutton Birds return in flocks, and it’s quite a beautiful sight see them completing their journey, knowing just how far they’ve travelled to be here.
Each pair will lay just 1 egg per year, in late November. Both Mum and Dad share incubation, taking shift of up to 2 weeks at a time while the other flies out to sea to feed. Incubation lasts about 53 days. Adults take turns feeding the chicks until mid to late April when they will leave the chicks behind to start their migration. The chick, quite phenomenally, will follow 2 -3 weeks later on their own.
Tasmania is the only state which still allows the harvesting of Mutton Bird chicks during a short, 15 day season in April. The chicks are harvested for their down, meat and oil. The meat produced is oily and rich in flavour, the oil is incredibly rich in Omega 3’s Moonbird oil used both as a dietary health supplement and in topical creams for a range of health issues. Natural predators include Pacifc Gulls, Ravens, Swamp Harriers, Hawks, Eagles. Shearwater eggs are also sought after by Silver Gulls, lizards and snakes.