The gentle stare, the silent watch of a tawny frogmouth carried the message that autumn was on the way.
The temperature may have hit 22 degrees, the hot sun casting dappled shadows over the Waterworks Reserve, but the frogmouth just knew. It was the same last year. At the height of summer, the frogmouth was getting himself in position to prepare for the change of season.
This year the male frogmouth – soon to be followed by his mate – arrived at his favourite autumn and winter roost on the night of January 26. They were a little earlier in 2025, arriving on Friday the 17th.
I enter such dates in my diary to keep track of the seasons but the frogmouths do not need a written record. They have an innate calendar and, for that matter, a clock which gives more or less precise notion of time and place. It’s the same for all bird species.
There’s something remarkable in the fact that migratory birds, according to my anecdotal records, arrive at the some time each year, although there might be delays caused by adverse weather over Bass Strait or on the mainland.
The first of the migrants to my patch are the striated pardalotes, which I hear calling before the end of winter, usually around August 14th. As soon as I hear the pardalotes, the descending trill of the fan-tailed cuckoo rings out.
From country districts, I always receive reports of an even earlier arrival, that of the swamp harrier which times its crossing of Bass Strait to coincide with an early nester, the masked lapwing which loses eggs and chicks to the raptors.
How do they do it? How do birds know exactly when to travel. It’s written in the changing length of the day and, during the migratory journey, in the stars and the position of the sun and the earth’s magnetic field. Birds have internal biological clocks that control behaviour and their physiology which changes throughout the year. They also use sight and smell to find their way.
The frogmouths vanish in the first week of spring to another site, which forms a nesting territory, with at its heart a platform of sticks in the fork of a tree. Although I have searched each year, I’ve never found the nest, which adds to the mystery of the birds’ arrival and departure. When people see me out and about in summer, scanning gums and wattles, they tend to look askance when I tell them I’m hunting the “holy grail” of nests.
It’s not just about migration. I have a forest raven that regularly visits my garden for a hand-out of pieces of cheese. But it’s guaranteed to arrive on a Saturday morning, at around 10am. That’s the time we cook a bacon-and-egg breakfast and bacon rind, for the raven at least, is on the menu.