It’s one of the paradoxes of birding that you often see more birds when conditions are dry, at least in the near-coastal regions where the majority of us live. The reason is that many of Australia’s nomadic birds leave the driest areas during drought and move toward the coast to take refuge in better watered areas. As ephemeral lakes and rivers dry up, water birds are forced to congregate in the remaining permanent waterholes, often travelling hundreds of kilometres to do so. Bush birds leave their usual territories as there are few insects and scant flowering in the parched conditions. Sedentary birds might fail to breed or even die, but those species with a tendency to move long distances can end up almost anywhere in the country.
So, while we might see fewer individuals of our resident species during a dry year, we see a larger number of nomads with the influx of drought refugees from further inland.
This year (2017) proved to be an extraordinary example. Take the Red-capped Robin. If you’ve ever been to the drier woodlands west of the Great Dividing Range — especially the mallee, mulga and native cypress areas — you’ve probably seen them. Common and widespread throughout the inland, they’re generally fairly rare along the eastern seaboard and mountains where the forest is denser and the understorey thick. Here, it’s normal for the occasional bird to turn up during drought years. They stay for a brief period and then disappear as suddenly as they arrived.
But this year, something unusual was going on. During September and October we had no fewer than 20 separate records of Red-capped Robins in the Blue Mountains alone! That’s double the number of records we received during the previous ten years combined. They were seen from Winmalee to Mt Victoria, with one pair even nesting at Lawson — the first confirmed breeding record in the Blue Mountains. But this pair weren’t unique in their readiness to reproduce. During November, Kalang and Milo Morrison-Jones and Ira Dudley-Bestow (three competent young birders affectionately dubbed the ‘Intrepid Trio’ by older members of the Blue Mountains Bird Observers) found seven pairs during a bushwalk into the Kedumba Valley below Wentworth Falls, including five pairs with fledglings.
A look at Birdline NSW for spring 2017 reveals plenty more sightings closer to the coast, from the Hunter to the Illawarra, Shoalhaven, and scattered across Sydney itself.
It wasn’t just Red-capped Robins. In early September, Pallid Cuckoos arrived in the Capertee Valley as they do every year, but this time they were so abundant it seemed you could stop almost anywhere in the valley and find one in a nearby tree. At the same time they started appearing around coastal Sydney and the Blue Mountains in locations where they’re not usually seen. The Pallid Cuckoo is more typically at home in the lightly timbered, open country we find west of the divide.
Even more unexpected were the Brown Songlarks. This is a species associated with treeless plains where they perform high display-flights, parachuting on raised wings as their metallic song carries across the grasslands. Close to home they regularly appear on the river flats of the Capertee Valley and the Hawkesbury flood plain, but what a surprise it was to hear that Kalang had seen three (and photographed one) in Katoomba during September. Indeed they are known to be irruptive during droughts. Since August they’ve also been reported from Sydney airport, Centennial Park, Eastlakes, Kurnell, Sydney Olympic Park, Royal National Park, Port Kembla, Riverstone, Long Reef and amazingly, Lord Howe Island.
The list goes on. Here in the mountains we also had Rufous Songlark, White-winged Triller, Little Grassbird, and more Painted Button-quail than usual. Little Bitterns were calling from the dense reedbeds at Lake Wallace and crakes darted in and out of the reeds. Masked Woodswallows were prominent among the White-browed in vast mixed flocks that we tend to see more of in dry years.
Across the wider Sydney region came reports of Painted Snipe, Banded Lapwing, Black-eared Cuckoo, Red-backed Kingfisher, Black-tailed Native-hen, Glossy Ibis, Freckled and hundreds of Pink-eared Ducks. Black Honeyeaters appeared in the upper Hunter and Capertee Valleys, with the Hunter also producing Australian Pratincole, Little Button-quail, Red-winged Parrot, Crimson and Orange Chats. Further south, four Orange Chats created a stir at Jamberoo, hanging around for at least two weeks with evidence they might be nesting. It all reads like an outback trip report, yet it’s not the outback. And this is by no means a complete list.
The rainfall data from the Bureau of Meteorology website helps to explain things. A wet 2016 had provided favourable breeding conditions with bird populations across the inland booming. But by autumn this year conditions were changing; southern Queensland was already drying out. Then, a very dry winter gave us rainfall deficiencies across much of Australia, especially a large area extending from South Australia through most of NSW. In September things got worse: both NSW and the Murray-Darling Basin had their driest September on record. This was combined with exceptionally warm temperatures which hastened the drying out of soil and watercourses.
Such harsh conditions coming on the heels of a boom year would result in stiff competition for very limited food resources. It’s no wonder so many birds have been forced to move long distances in order to survive. In 35 years of birding I cannot remember another year quite on the scale of this one.
An earlier version of this article was published in the November 2017 ‘Blue Mountains Bird Observer’ and Cumberland Bird Observers Club December 2017 newsletter. Records were sourced from Blue Mountains Bird Observers, Birdline NSW, personal communications and my own observations. I especially wish to thank Kalang Morrison-Jones for his regular emails full of interesting sightings.
Postscript: Significant rain in October and November eased the rainfall deficiencies across much of the country. Accordingly, the sightings of inland species slowed, though a few from earlier have hung around — like the nesting Red-capped Robins.
Happy New Year to all my readers.