Sarus Crane FAQ 3
This page covers Sarus Crane habitats, behaviour and conservation, including interactions with Brolgas. Size, calls, locations and population numbers are in FAQ 1, and food, drinking and breeding are in FAQ 2. Background to Brolgas and Sarus Cranes with comparison photos is on Ozcranes Australia/New Guinea Cranes Intro page.
← View from volcanic cone Halloran's Hill, Atherton, far north Queensland. The surrounding ‘golden triangle’ of fertile basalt soil supports maize, peanuts, cattle pasture and more recently sugar cane. On average 1,700 Sarus Cranes feed here during the non-breeding season, and the large water storage (Lake Tinaroo) provides daytime rest sites and night roosts (G & J Holmes)
Sarus Cranes need water every day and always roost beside or in shallow water at night. On the Atherton Tableland, far north Queensland, non-breeding flocks usually leave at dawn to feed in nearby farmland, but may loaf at the roost site for periods during the day. Feeding may continue after nightfall with surveys recording cranes (presumed Sarus on the basis of birds already counted in daylight) arriving at many roosts after dark. Since counts began in 1997, Sarus Cranes have deserted particular roosts after (and presumably due to): water levels raised in private storages; cattle removed and site overgrown with long grass (tropical pasture species 1-1.8m); tree-planting; and suburban development on lake shore.
Gulf of Carpentaria wetland with flooded grass and scattered trees, typical Sarus Crane breeding habitat (John Grant) →
Habitat comparison with Brolga In northern Australia Brolgas co-exist with Sarus Cranes, but based on records so far, Brolgas use a much wider variety of habitats with Sarus found mainly in swamp woodlands, swamps, croplands and grasslands. At breeding sites, Sarus Cranes apparently have differing nest site preferences. In mixed non-breeding season flocks one species usually predominates, but as yet there is no rule of thumb about Brolga dry season habitat selection compared with Sarus Cranes. On the broad basis of ‘wetter’ vs. ‘drier’ habitat, some surveys show no apparent difference; in other instances Brolgas are found in wetter sites or districts and Sarus drier ones; other surveys show Brolgas using drier habitats than Sarus. (This explains the conflicting habitat accounts in popular bird field guides). There's a lot of complexity to be sorted out to improve our understanding of Brolga/ Sarus Crane habitat differences and interactions in Australia, a PhD study is now underway.
Sarus Crane family preening, Sarus pair displaying: Atherton Tablelands (Sandy Carroll)
Behaviour compared with Brolgas There have been no systematic studies of crane behaviour in Australia, and for Sarus Cranes we even have few observations. Roost behaviour, unison calling, pairbonding and dance displays are believed similar to Brolgas». Flight behaviour for both species is covered in Ozcranes Flight Gallery»
Behavioural interactions with Brolgas Height is a significant factor in establishing dominance among cranes. In non-breeding feeding flocks Sarus, being on average slightly taller, may ‘crowd out’ nearby Brolgas, effectively staring them down till they move several metres away. At one major non-breeding season roost, Bromfield Swamp on the Atherton Tableland, over 200 Brolgas roost with up to 800 Sarus Cranes, but some observers report the Brolgas arrive earlier to roost, and stay longer on site in the morning. On the breeding grounds in NW Qld, Sarus pairs aggressively defend their nest site against nearby Brolgas, other Sarus and also other large birds like swans. There is anecdotal evidence that Brolgas and Sarus Cranes have been hybridising in the wild in northern Australia, a PhD study is now underway (link below).
The Action Plan for Australian Birds 2000 (and subsequent plans) included Sarus Cranes, but at the lowest level ‘Least Concern’. This can be questioned due to information on low annual recruitment rates as well as the apparently restricted nest habitat and nesting locations for Australian Sarus. A range of risks and hazards for Sarus Cranes and Brolgas is covered in Ozcranes Conservation»
More.. A significant PhD study» is now underway on interactions between Brolgas and Sarus Cranes in Australia.