* Only about a third of previously used nest hollows are used in any one year, but if a hollow is used one year there is a 50% chance of it being used the next. The clutches raised in the hot/dry and wet/cool years were similar (26 and 32 respectively). In Canberra, in two hot, dry years, no hollow bearing dead trees were utilised while in the two most recent wet and cooler years, 6 hollow bearing dead trees were utilised. They appear to be choosing nest hollows on the basis of climate experienced. Gang-gangs line their nests with bark chips of a distinctive shape and size. * At least some Gang-gang pairs will prepare multiple hollows before choosing one as a nest. The rate of predation is unknown but the project confirmed Brushtail Possums as a significant predator of eggs and chicks. Brushtail Possums are the major hollow competitor. There is an on-going project in Canberra to help determine whether sites are limiting. These results possibly suggest that at least in the Canberra area hollows are not a limiting factor and that competition from other hollow nesting such as cockatoos and parrots is not a major factor. Of these we found:ĥ% leaf-lined suggesting possum or perhaps Galah use * 216 of hollows, in the Canberra, Cooma and Tumbarumba areas, that were of interest to Gang-gangs were closely monitored. Low altitude sites, such as Campbelltown (50m) may have a breeding period 2 months in advance of that at high altitude locations, like Cooma (1000m). Hollow dimension data has been collected from most of the hollows as has fledging success rate, fledging sex ratio (0.7 females to 1male) and timing of fledging. A significant relationship was found between fledge time and altitude. * A further 25 nest hollows have been identified across much of the Gang-gang's range. Highlights of last season’s research include Gang-gang hollow checking is increasing as we approach breeding season and we ask that you keep posting sightings of where you observe Gangs-gangs looking into hollows, but particularly in remote or rural areas away from Canberra. We have 5 years of good data from Canberra but would like to compare what we are finding here with that elsewhere. We continue to learn much about Gang-gang nesting ecology and behaviour. In total we have now identified 60 nests (52 in Canberra, 2 in Campbelltown, 2 in Wombat State forest (Vic) and one near or in Moruya, Cooma, Tumbarumba and East Melbourne).
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