Relatively little
A number of Australian birds have the epithet “little” in their common name. But for some of these there is only a marginal difference between the “little” species and another closely related species. So, unless you happen to see both species close up and together, for the non-expert it is not immediately obvious which is the “little” species, and therefore other distinguishing features such as plumage, habits or call must be used for their identification. For example, we have the Little Corella only slightly smaller than the Long-billed Corella, and the Little Raven only marginally smaller than the Australian Raven. Similarly, the Little and Red-chested Button-quails are essentially the same size.
For the pied cormorants there is undoubtedly a size difference between the Little Pied and Pied, but when trying to identify and photograph a wary bird through rushes and sedges on the other side of a wetland (see photo above), size is not so easy to determine. With declining eyesight and without binoculars at hand it was only by studying the photos later that we were able to recognise our bird as a Little Pied Cormorant, because of its (relatively) stubby orange/yellow bill and its all-white face, compared with the Pied Cormorant’s long slender pale bill and distinctive face colourings. The Pied also has a shorter tail and black thighs/flanks, and in fact is in a different genus, Phalacrocorax, from the Little Pied’s Microcarbo. The clincher is the Little Pied’s crest on the forehead which can just be seen slightly raised in the photo at right which was taken a couple of days later from a more advantageous spot on our wetland.
Interestingly, there has been some recognition of the inadequacy of the “little” descriptor: the Australasian Grebe was formerly known as the Little Grebe despite being only slightly smaller than the Hoary-headed Grebe, and the Little Thornbill was changed to Yellow Thornbill, acknowledging that it is in fact much the same size as other thornbills.
So with bird identification, maybe size doesn’t matter – there are more important things to consider?!