One of my readers used the workaround ‘comment’ routine recently to ask me about some birds she sees on her side of Ross River:
I live on the river in Annandale and since moving here 18 months ago have developed a great love of birds – they are in my garden and on the river. I manage to identify most of them but there is one little fellow I just can’t – I have googled, looked in the books and sites.
It is not a very pretty little bloke but I love them. They are, I would imagine, a finch, [with] the round little fat body, always in a flock of around 10 -15, fly very fast, love the seed in my lawn, love my bird bath as it’s very protected. He is a medium flat brown with a black mask across his eyes, has a short tail, easily frightened.
This little bird is too small for me to get a photo with my camera. Malcolm do you have any idea what it is, I would be grateful for your comments.
I was happy to help, especially as Lynne had provided such a good description that there was only one real candidate, the Spice Finches (Lonchura punctulata). As I told her, they are Asian birds, relatively recent arrivals in our region but now well established in our parklands, so older bird books might not describe them, or might not show them as living here.
I have already written about them here and, more recently, here but Lynne’s enquiry reminded me that I had intended to write about them again after my return from Bali in April (this link will lead you to earlier posts about the island). They are a native species there, so seeing them was no surprise. Seeing them feeding on a tidal rock platform, however, was quite unexpected.
Wikipedia tells us that closely related species, at least, are known to feed on algae:
The scaly-breasted munia or spotted munia (Lonchura punctulata), known in the pet trade as nutmeg mannikin or spice finch, is a sparrow-sized estrildid finch native to tropical Asia. … This species is found in tropical plains and grasslands. Breeding pairs construct dome-shaped nests using grass or bamboo leaves. …
The scaly-breasted munia feeds mainly on seeds but also eats small berries such as those of Lantana. … Like some other munias, they may also feed on algae, a rich protein source, prior to the breeding season.
I do like the idea of our Spice Finches feeding on Lantana (we have far too much of it!) but I was more interested in the comment about algae. The references to that last sentence are to a blog post and this academic study, Avery (1980), pdf, to which it refers. The key point is:
The earlier post on the Scaly-breasted Munia (Lonchura punctulata) feasting on casuarina seeds mentioned another food, the green alga Spyogyra that grows in stagnant or slow-moving, relatively unpolluted water. …
According to Avery (1980), “Apparently Sharp-tailed Munias (Lonchura striata) eat Spirogyra as a source of protein to enable them to become physiologically ready for breeding.” This probably also applies to the Scaly-breasted Munia.
Those observations were of birds in Malaysian rice-paddies, i.e. fresh water, but it’s not a big step from there to the Balinese tidal rock platform.
Perhaps we should be looking out for our local Spice Finches feeding on algae in Ross River?