Large flocks of little corellas, such as those spotted at Queens Park in Sydney's east on Monday, have become more common over the past decade, Richard Major, principal research scientist at the Australian Museum, said. Loading 'Kookaburras are everywhere!' First came ibises as wetlands dried up or were developed into housing or for other uses, followed by sulphur-crested cockatoos and corellas. "They're adapting to the reliable resources," Dr Major said, noting that well-watered and fertilised parklands provide relatively abundant seeds and other fruit for parrots to feed on.

Likewise, nectar-eating rainbow lorikeets have discovered new sources of food, such as gardens planted with year-round flowers. Others, meanwhile, are picking up signs of unusual gatherings, including one collection of about 10 kookaburras sitting on a single branch at a home in Avalon on Sydney's northern beaches. "We've never seen anything like it - there are kookaburras everywhere and we assumed it has something to do with the lack of rain," Arianne Martin said. "They are not exactly going to move back to their previous abode", Mr Shiels said of the various migrants.

No laughing matter: Kookaburras gather on a single branch at Avalon on Sydney's northern beaches. Credit:Kevin Martin 'Pretty large margin' Just as Sydney has been relatively dry, so has most of the state. Both NSW and the Murray-Darling Basin recorded less than half the typical winter rain, at 46 per cent of the norm, the bureau said. It was the eighth-driest winter on record for NSW - now declared to be fully in drought - and the driest since 1965. Nationally, rainfall was a third below the average for winter.

Daytime temperatures continue to be exceptionally warm, with Australia and NSW alone posting their fifth hottest winters on records going back to 1910, the bureau said. For NSW, though, the year-to-date maximum temperatures continue to be "the largest on record by a pretty large margin", Blair Trewin, senior bureau climatologist, said. So far in 2018, average daytime temperatures are running more than 2.2 degrees above the 1961-90 baseline used by the bureau. That beat the previous NSW record by 0.4 degrees set only last year - which itself was 0.4 degrees ahead of the next warmest period, Dr Trewin said. Mean temperatures, which average out days and nights, are also running at a record year to date in NSW even with the clear skies dragging down minimum readings, he said.

Lowest inflows? One effect of the low rainfall and high temperatures is that reservoir levels have been dropping rapidly. David Harris, chief executive of WaterNSW, told budget estimates on Friday that inflows to Sydney's water catchment are on course for a record low year.

On current trajectories, Sydney's inflows may total just 83 billion litres, well below the previous lows of 136 gigalitres in 1944 - before the commissioning of the city's biggest dam at Warragamba - and 234 gigalitres in 2004 during the Millennium Drought. Loading Justin Field, the Greens water spokesman, said the Berejiklian government should consider accelerating water restrictions and urging consumers to use water more wisely. “It makes sense to bring in Stage 1 water restrictions now, ahead of the normal 50 per cent dam level trigger, to reduce the likelihood of more extreme restrictions down the track," Mr Field said. "But ultimately we can only address long-term water security issues by getting serious about water efficiency and investing in greater recycling and reuse."