This Pacific Baza was filmed in Samsonvale in southeast Queensland. They can also be seen around the northern rivers.
Mary Gardner
The noisy miners shriek as the Pacific Baza (from Hindi, pronounced ‘bar-za’) settles. She shakes her feathers like the Vedic goddess who can toss her head and rearrange the order of the stars in the very heavens. She is a hawk, Aviceda subcristata, with sharp eyes scanning the leaves of acacias and eucalypts for her prey, the phasmids (from the Greek for ‘spectre’). These stick insects are large (30mm to 300mm), barely visible animals who freeze when they are discovered. But the Baza spots them anyway, darts through branches and seizes them with her feet. She’s extra hungry in the spring, as she joins her mate in sky dancing and nest building.
Since 1977, this striking bird of the tropic/subtropic zones has been shifting with the climate and expanding its range southward. Last week, a surprising sighting was reported in the central west slopes of NSW. Over the past month, there were three sightings that I know of in my neighbourhood. Who else has seen this bird?
Who has also seen the phasmids? They eat the leaves of eucalypts, acacias and melaleucas. There are about 150 Australian species, each of whose lifecycles spin across the spectrum of possibilities. Tiny copies of adults hatch and grow through several moults. Each time, their eyesight becomes sharper until as adults they switch from feeding during the day to night.
Some females have wings and wander. Some do not and await males who do. But many species are entirely female, virgins laying eggs that hatch more females. Now and then, males are created and readily accepted as sexual partners.
The eggs laid in the leaf litter look like small seeds. Some have a little knob on top. Certain ants carry the eggs back to the nest and serve the knobs as treats for their sisters. They ignore the actual egg but leave it in the nest, which protects it from other hazards.
Meanwhile, the trees grow. But while unfurling leaves to the sun and winds, they also delve through the soil, their hairy roots in the company of subvisibles such as bacteria and fungi. Since the time of the dinosaurs, trees found that even in soils that lack some vital nutrient, there were relationships to be had with microbes that could supply these. All parties benefit.
WH Verboom and JS Pate are two Australian soil scientists who can point out many such relationships. Nitrogen-fixing bacteria with acacias and fungi with eucalypts are well known examples. But their work has led them beyond into what they call the ‘phytotarium’.
This is a vision of the underground created in tree time. The root and microbe activities build the very soils that maintain and enhance their lives. Clay pans are formed to store water. Carbonates are accumulated in nodules or layers. Iron and silica line root channels. Sand is bound together, creating micro-pores and tubes. Within these embraces flow water, minerals and by-products of photosynthesis from above.
From root to leaf, nutrients, minerals and even pollutants circulate. The phasmids will be nourished or sickened and in turn the Baza too. Recently, V Jaspers and other scientists found methods to determine the levels of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and other persistent organic pollutants (POPs) in a bird of prey by analysing a single feather. The results are literally a ‘message from the universe’.
Even as the Baza moves southward, are nontoxic environmental practices on the land and in town becoming the norm quickly enough? Then this bird, which Aboriginal folklore identifies as a herald of good fortune, can continue across space and time to embody hope.
You can log a sighting with the Atlas of Living Australia www.ala.org.au. But how about our own Wild Byron Atlas! Learn more about this proposal by Nature Science Network at www.naturesciencenetwork.wordpress.com or attend the free Science Film and Talk Fest session ‘Listening & Hearing Worlds’ on Friday October 19 at 6pm in the SCU room at Byron Bay Community Centre.
