Comparing the Two Atlases
Birds Australia has conducted two major mapping and recording projects surveying Australian Birds (First Atlas 1977-1981 and New Atlas 1998-2002). This comparison allows us to assess whether birds are declining, increasing or remaining stable over a 20-year period.
|Atlas 1||Atlas 2|
|No. 1° grids||812||809|
|Surveys per grid||101||269|
Only surveys like the Atlas can give a true picture of what is happening to birds at the continental scale.
- Of 422 birds tested, 201 (48%) showed no change, 157 (37%) were recorded more frequently during the second atlas, and 64 (15%) were recorded less frequently during the second atlas. Rainfall was better in the second Atlas, accounting for some of the differences.
- For 247 species (59%), the detected changes varied between regions i.e. the changes were not the same in all regions.
- A number of native species increased (e.g. Lorikeets and Honeyeaters), partly as a result of their ability to use urban and rural tree plantings. Plantings in parks, gardens, streetscapes and farms have favoured these species.
- Wet forest species (rainforest) - e.g. Orange-footed Scrubfowl, Noisy Pitta, Tasmanian Scrubwren. This is partly because of increased rainfall in the second Atlas period, resulting in greater production of nectar, fruit and seeds.
- The climate during the second Atlas may also have favoured opportunistic breeders (e.g., finches, and honeyeaters) allowing them to breed successfully and increase in number.
- Is an increasing species a good thing? Not always - some introduced species increased (e.g., Common Myna) and some native species that exploit modified habitats also increased (e.g. Crested Pigeon) suggesting that habitat change (e.g. urbanisation) has driven the increase.
- Declining species tend to be ground-dwelling species such as Bustard or Brolga. This means that grazing and fire regimes need more management attention, as do the effects of introduced predators.
- There are also many woodland species that have declined (e.g. Hooded Robin, Diamond Firetail, Dusky Woodswallow). Birds that breed in temperate woodlands are declining. Thus we need to manage woodland habitats, and in particular prevent further major degradation and clearing of these habitats.
- Some waterbirds and migratory shorebirds declined, probably because of wetland destruction and degradation, both inside and outside of Australia.
- Honeyeaters and Pigeons increased because of higher rainfall and better conditions over much of Australia.
- Wet forest species have moved south into NSW and Victoria as a result of the higher rainfall and better conditions compared with 20 years ago.
- Fruit-eaters (e.g. Rosellas, Pied Currawong, Satin Bowerbird and White-headed pigeon) have increased, partly as a result of horticultural expansion, and partly as a result of greater rainfall and fruit availability.
- Many waterfowl have increased (e.g. Magpie Goose and Australian Shelduck)
- Declining species tend to be ground-dwelling species.
- Emus declined extensively.
Birds Australia (03) 9882-2622