Little Eagle - Distribution and Abundance

Distribution and Abundance

Although the Little Eagle has a large range and can be found in most parts of Australia, except heavily forested parts of the Great Dividing Range (Marchant and Higgins, 1993). Like so many Australian natives, it faces a deteriorating population due to a loss of habitat and competition from other species. One of the biggest factors to the decline of the Little Eagle is the decline of rabbits due to the release of the calicivirus, interestingly the eagle relied heavily on the rabbit population due to the extinction and massive decline of native terrestrial mammals of rabbit size or smaller such as large rodents, bandicoots, bettongs, juvenile banded hare-wallaby and other wallabies (Sharp et al. 2002).

In the first national bird atlas in 1977–81, the little eagle was reported in 65% of one degree grid cells across Australia, with mostly high reporting rates (more than 40% of surveys per grid) across New South Wales and Victoria. Breeding was recorded in 11% of cells, with the highest rates in New South Wales (NSW) and Victoria (Blakers et al. 1984). During the second national bird atlas in 1998–2002, the little eagle was recorded in 59% of grid cells, at mostly low reporting rates (recorded in less than 20% of surveys per grid). Breeding was recorded in 5% of grid cells (Barrett et al. 2003, 2007). Overall, there has been a national decline in reporting rate of 14%. In NSW over the last 20 years (two little eagle generations) the decline in reporting rate has been 39%, and over the past 30 years has been 50%, with an accelerating trend since the 1990s (Bounds 2008). The decline in reporting rate over the past 20 years for the South Eastern Highlands bioregion has been greater than 20% (Barrett et al. 2003, 2007). This bioregion includes the ACT.

The little eagle was once common in the ACT (Olsen and Fuentes 2004) but has undergone significant decline (greater than 70%) over the last 20 years. In the late 1980s there was an estimated 13 breeding pairs in the ACT. The species occurred mainly in the northern half of the ACT with the highest concentrations found in the Murrumbidgee and the Molonglo river corridors (Taylor and COG 1992). By 2005 the only breeding record in the ACT was of an unsuccessful nest near Uriarra Crossing (Olsen and Fuentes 2005). A more intensive ACT survey in 2007 found three breeding pairs, which fledged a total of four young (Olsen et al. 2008). In 2008 four breeding pairs were recorded and four young were fledged (Olsen et al. 2009). In 2009, three breeding pairs were recorded with three young being fledged (Olsen et al. 2010).

Typical habitat for the little eagle includes woodland or open forest. Higher abundance of the species is associated with hillsides where there is a mixture of wooded and open areas such as riparian woodlands, forest margins and wooded farmland. Little eagles usually avoid large areas of dense forest, preferring to hunt in open woodland, where the birds use trees for lookouts (Marchant and Higgins 1993; Ferguson-Lees and Christie 2001). In the ACT, little eagles inhabit frequent open woodland and riparian areas (Olsen and Fuentes 2004).