STEP Matters 179 (p6–7) contained an excellent article by Jill Green entitled A Threatening Species – The Noisy Miner. It correctly described the noisy miner as a 'threatening species in their aggressive defence of their territory against other birds' and even bats, cats, koalas, and cows (!) and that they are listed as a Key Threatening Process under two government acts. Streuth, they sound dangerous! However, I would like to offer some words in their defence.
In the 1980s and 1990s we neighbours on the borders of Twin Creeks Reserve, Turramurra, had about a dozen Indian mynas nesting here and up to some 40 m into the reserve. The Indian myna is an exotic, listed by the World Conservation Union as one of the World’s 100 Worst Invasive Species. It is not to be confused with the Australian noisy miner, a native bird that I, for one, am fond of for its cheeky habits and fearless attitude to bigger birds.
The Indian myna in contrast is a city slicker, preferring the stink, noise, and rubbish of the city to the bush. Indian mynas in Australia are ferals that can be legally destroyed but are protected by law from cruelty. Also known as ‘flying rats’, they aggressively frighten off most other birds – but not the noisy miner! No way!
Groups of noisy miners would hassle singles or pairs of Indian mynas, chasing them from tree to tree and away. Sure, groups of noisy miners (aka ‘soldier birds’) also hassle other birds, even currawongs, and dive bomb (without quite hitting) the sleepy tawny frogmouths in their day roosts and nests. (Yet, when the parents are off the nest, I’ve never seen miners hassling the defenceless fluffy white chicks.) Both currawongs and frogmouths eat nestlings, so I accepted the noisy miners’ assertive habits.
My point is, noisy miner groups can outnumber and dominate the Indian mynas locally, and possibly helped limit their numbers in my local area. Few other birds can do so, requiring the particular characteristics of fearless aggression and cooperating in groups against a common enemy. Of course, these are the very features that make the noisy miner the 'threatening species in their aggressive defence of their territory'.
My main story concerns the noisy miner’s protection of other species’ nestlings. Listen closely, those that claim miners ‘break eggs and kill chicks’ of other birds.
In 1993, my neighbour felled a tall thin tree that harboured a butcher bird’s nest, from which his young kids were being dive-bombed. The kids showed us the dislodged nest and two frightened nestlings crawling on the ground, one with a broken leg. We took it away to get splinted.
My wife Lesley, a volunteer with WIRES, opted to rescue the birds and put them and the nest into an open cardboard box and set it on a stump. We planned to move the box 50 m every day towards the bush reserve 100 m away, hoping the butcher bird parents would feed their young. They did not, however. So Lesley fed them tinned baby food.
The immediate carers of the nestlings were a group of (very) noisy miners (varying from 4 to 12) gathered excitedly on or near the edge of the cardboard box, peering in, apparently keeping predators at bay.
Next day we saw a life-and-death running battle between pied currawongs and noisy miners. The cardboard box, now only 40 m from the bush, sat on a rock outcrop in our garden. Currawongs would attack from above, swooping low, and be chased off by the swarming miners. The mid-air battles resembled fighter aircraft attacking slower enemy bombers. I hurriedly fitted netting over the box. The miners remained on guard but the threat was much reduced.
On the third day, I fixed the nest into a tree in the bush. At last the butcher bird parents arrived to feed their young. The miners now left.
The larger nestling with the broken leg often fell off the nest, to which I returned him. But he eventually disappeared, taken by some predator. The smaller nestling soon fattened up and a week later was flying.
Later the male butcher bird (whom wed been feeding) landed on my head from behind, reached its beak down to my right eye, and hooked a bloody cut right through my eyebrow. Unusual behaviour. So much for gratitude and for bird IQ – or should we question our own IQ for interfering with nature? And, by extension, for government plans to interfere with noisy miners in their natural habitats? I cannot really believe that miners 'break eggs and kill chicks' unless they themselves are threatened.
In summary, bear a kind thought for the much maligned noisy miners! They possibly help in restricting the spread of Indian mynas, and they sometimes protect the nestlings of other species from larger predator bird species.
Indian myna (left) and noisy miner (right)