The day before Christmas a book arrived mysteriously in my letter box – no donor name and no memory of having ordered it for myself. Before I began reading it, I crowd-sourced a search for the giver, and discovered her, currently taking possession of Amsterdam, the friend whose book-gifts have opened worlds to me over the years.
This book is “On Track”, an account of John Blay's attempts to find the old Aboriginal route from the high country near Mt Kosciuszko to Eden on the coast, the link between feasting on bogong moths and feasting on whales. The country he traverses is wild, rugged and remote, and very close to where I live.
Early every summer, when the children were small, we used to be visited by stray bogongs, who congregated on the inhospitable glass of the French windows, banging against them, large and furry. I knew then that the moths were heading for the high country and that they were eaten by the ancestors.
But I didn't know the technicalities of gathering and cooking till Blay enlightened me.
The moths congregate in vast numbers in caves in the high country. They cling, massed, to the walls. Blay touched one and thousands peeled off and formed a squirming crush on the floor. Blay comments “It's a demonstration of how readily they might be harvested.” (p. 24)
How they became a feast has always puzzled me (although not enough to check it out). Blay solves the puzzle for me. You cook them, winnow out dust and wings, and pound them into fatty cakes which last a few days, longer if they're smoked. (p. 26)
Then of course I consulted Mr Google and found plenty more details.
They have a wingspan of about 50mm, dark brown mottles and two light spots on each wing, and fly up to 1500 kilometres in their year-long life. Bogong moth expert Ken Green says they are the second biggest energy input into the mountains, after sunlight.
Larva develop in ground now poisoned by low levels of arsenic which is stored in the body of the adult, and then leaches into local soil when they die. Because they die in large numbers, 1.5 metres thick on the floor of some Alpine caves, representing many generations, the arsenic becomes concentrated and a potential threat to anything that eats them – antechinus, spiders, lizards and Mountain Pygmy Possums.
Deceived by artificial lights into thinking it's sun-up and time to rest, they can disrupt air-conditioning, cover lighting for sporting fields, and become a nuisance at barbecues. They smother buildings with a dark coating of moth, infiltrate Parliament House in Canberra and one even perched on Yvonne Kenny's nose at the closing ceremony of the Sydney Olympics.