Small patches can be valuable for biodiversity conservation: two case studies on birds in southeastern Australia

Presence/absence datasets on birds from two landscapes in southeastern Australia were analysed as a case study to examine the conservation value of small habitat patches. In the Tumut landscape, patch sizes ranged between 0.5 and 97.6 ha; 30 species of birds (37%) were observed in patches of up to 1 ha, and 74 species (91%) were found in patches of up to 10 ha. In the Nanangroe landscape, patch sizes ranged from 0.4 to 15.6 ha, and 74 species of birds (75%) were found in patches smaller than 1 ha. In both landscapes, small patches contributed strongly to species accumulation curves. While large patches are needed by many species to maintain viable populations, it is important to recognise the complementary value of small remnants. In many landscapes, the conservation and restoration of small patches will often be the only feasible management option.