Monday, January 16, 2012
The birthday of 23 million mutton birds
Every year, around January 15, Australia's 23 million short-tailed shearwaters (mutton birds) hatch their eggs. It's the birthday of tiny chicks covered in grey down. Although the date varies by a couple of days either side of January 15, this is the day when most of the mutton bird eggs hatch; eggs that were laid around November 25.
It's an exciting time in the rookery. The birds are extra noisy as they 'talk' about the hatching and 'discuss' feeding rosters.
From now until maturity in late April, the mutton bird chicks will eat enormous quantities of krill and small fish, delivered to the burrow by the returning parents.
For the first week or so one parent will stay with the chick to keep it warm and safe, while the other goes out fishing -- either in Western Port Bay or Bass Strait.
In our Ventnor rookery we have about 2000 birds. This is one of the smaller rookeries on Phillip Island. Swan Lake also has a rookery. On Cape Woolamai (also on Phillip Island) the mutton bird colony has about three quarters of a million birds. Phillip Island has about 1 1/2 million birds in total; with the Australian population of mutton birds about 23 million.
When we lived on King Island, our property had both mutton bird and penguin rookeries. It was here that I first became interested in these birds and began studying their habits -- and writing about them. One of the first books I wrote was called Moonbird. Written for children aged between eight and 12 years, the book was fiction, based on King Island with a strong mutton bird connection. The book is in many libraries throughout Australia.
Now on Phillip Island we live alongside another mutton bird rookery, so my study and interest continues. I never cease to be amazed by their life cycle and breeding patterns. Therefore, today I celebrate the birthday of all the mutton bird chicks newly hatched and living in sandy burrows on islands in southern Australia -- but especially in Bass Strait.