Leaf Watching.

Young leaves along the river trail glow in the aftermath of rain. Crimson. Bronze. Copper.

As the new leaves grow they change colour due to the green pigment that is Cholorphyll. Cholorphyll is a natural molecule engaged in an intimate tango with the sun and the wider ecosystem. It is also a very clever molecule. Its role is to capture the sun's energy so that it can be harvested for use in leaf and plant growth. By absorbing the sun's energy, Chlorophyll is able to synthesise carbohydrates from carbon dioxide and water and produce sugars in the form of glucose.

This whole process from energy absorption to flourishing plant life is known as photosynthesis, literally meaning 'putting together with light'. Photosynthesis is the basis for sustaining the life of all plants and, as humans and animals alike consume plants of all varieties, and as humans breathe the oxygen from trees, this wondrous eco-cycle is the basis for sustaining the life of the whole planet.

The young new growth along the river trail, the scarlet of the Callistemons, the coppery leaves of some Eucalypts and the crimsons of other gum species, have not yet been awoken to Cholorophyll's green energy. In contrast, the colour fiesta of deciduous leaves in Autumn has lost its Chlorophyll greenness and as the green fades, bountiful yellows, oranges, browns, reds and purples are revealed.

As the weather cools, the energy exchange between plant and sun begins to grow sluggish. The colour green from Chlorophyll is slowly sucked from the leaves allowing the beauty of the changing seasons to explode into multiple hues. The reds and yellows are present in the leaves all the time but are not visible until Autumn when the green from Chlorophyll slowly vanishes.

When the sun's energy withdraws and the days grow colder, the glucose stored in the leaves is transformed into myriad luscious shades of yellows (known as 'carotenoids') and reds (known as 'anthocyanins'). The brightness and intensity of the Autumn colour fiesta is based on the kinds of weather patterns experienced both before and during the withering away of the Chlorophyll molecules. Cold nights, clear sunny days and adequate soil moisture are the most favourable conditions for the most spectacular display of colour.

Jeffrey Dawson, Professor of Professor of Tree Physiology at the University of Illinois has studied the magical process of photosynthesis and comments almost with a scientifically-embedded religious fervour:

'Leaf pigments behind the flashy autumn display of color ... are much more than cellular trash. Recognizing tree colors not only for their beauty, but also for the complex and vital roles the underlying pigments play in forest function and survival, might just bring new awe and appreciation to the autumnal rite of leaf peeping.'

'New awe and appreciation' can perhaps be interpreted as a new spiritual movement of leaf watching in Autumn. While photosynthesis is the holy ritual of this new spirituality.

Whipbirds

The river trail was filled today with the glorious song of the Eastern Whipbird, the hooping of the pheasant-like Coucal and the chattering of flycatchers, wrens and other LBBs (Litte Brown Birds). The Whipbird's sonorous whistle echoes across the valley. Mostly, says the birdbook, they are heard but not seen so it was a special moment watching a pair of these smalll birds hop through the branches, chattering and singing (Frith, 1976).

The clever musicality of the Whipbird is created by both male and female singing together. The male starts off with his characteristic smooth 'Whip!', then the female completes the call with a high-pitched, drawn-out and beautiful 'choo-eeeeeee'. And here they were, the two of them, looking splendid, their head crests raised slightly, their olive feathered backs blending into the leafy canopy, and their fan-like tail swishing back and forth dancing among the branches.

Whipbirds are very active but shy. They forage in the leaf litter and logs lying on the ground searching for insects and larvae. And the birdbook reveals something else that's special about the Whipbird - they are 'an ancient group of species that are found no where else' (Frith, 1976: 396).

There's been a lot of rain lately. It's flooding in many locations across southern Queensland causing havoc. Here the river is running high, fast and brown. Lots of people are out and about jogging, rowing, walking their dogs, and as their dogs splash in the shallows between the Mangroves, we talk about the height of the river, the very high tidal flows and the return of the wet.

Looking up at what were sad and seemingly dead trees a few weeks ago, clumps of new shoots have begun sprouting from the branches, while the birds heralding the rain, the new growth and the revitalised life along the riverbank.

Reference
Frith HJ, 1976, Reader's Digest Complete Book of Australian Birds, Surry Hills, Reader's Digest Services Pty Ltd.

Splash!

Out of the corner of my eye I catch movement over the river. A raptor is fluttering. Hunting. Watching. Then suddenly it dives - swoosh! - and - splash! The kite rises back into the air clutching a fish in its talons. The kites may have abandoned their nest and been away for the past two weeks but today they are back, gliding along the river valley, swooping back and forth between the high branches of the eucalypts, then stopping to scrutinise the river below. I stop to watch their flight and feel a sense of relief.

A couple of weeks ago I couldn't watch what was taking place. As one kite sat on the nest, the other tried to ward off a gang of ravens and currawongs. About 20 birds were in the air, seemingly tomenting the kites with a sense of ruthlessness. One after the other the kites would rise up and try to chase these sky marauders away. Over and over again they took turns to chase away the birds and it seemed that, at least on this occasion, they were successful. But I could not stay all day to see what happened. Not long after this the kites disappeared. But today my heart soared.

It's been raining; the river is tidally high today and the fish are running. The kites know. It's a special moment.

The rain has brought more than the kites. There is wind in the air. A cool breeze which, for this river city, is unusual but when it comes, it's very refreshing. Just like the rain. And the smell of the sea. The tides have also brought the aroma of saltwater. It flushes round the mangrove roots and I can taste the salty air.

This small wild place is precious. The ecosystem is fragile in the midst of the city's vast development. But today I push the sound of the bulldozers and chainsaws out of sight and relish in the possibility that even in this fast-paced, vehicle worshipping, rapidly growing, tree-destructive city, such tiny pockets of the wild are sacred. The kites know.