Thursday, September 06, 2007

A Major Myna Mix-up!

The mynas around where I live have been up to things they shouldn't have, and at last I have the evidence!

After many months of trying (not too hard mind you), I finally managed to capture the hybrid Crested x Common Myna on ... whatever it is you capture digital images on. I saw the bird near the road as I drove my daughter home from school, dropped her off at home, grabbed my camera, and drove back to the site. This wasn't the first time I've done this, but this time the bird was still there!

As soon as I arrived the sun left, and the sky clouded over, which meant I had to push up my ISO to 800, so the photos weren't of the best quality. At first it sat in a tree preening. Then it flew down into a carpark the other side of a fence, which meant I had to contend with blurry fence in the foreground, but at least I got some pics!

Common Mynas were indeed the 'common' mynas in the area until recently. However, Crested Mynas, which were originally introduced here either deliberately or accidentally, have been aggressively expanding their feral population.

Common Mynas are very distinctive. They have a rich yellow patch of skin around the eye, and an orange-yellow bill. The iris is pale greyish-yellow, and the legs are orange-yellow. Note also the clear white vent. They have no tuft on the forehead, and the body, especially the underparts, is a maroonish-brown.

Crested on the other hand have a pale ivory-coloured bill, with some pinkish colouring at the base of the lower mandible, and a rich orange-yellow eye. The legs are pinkish-yellow. The vent is black with white tips to the feathers. There is a prominent tuft at the base of the bill, and the body is dark grey.

The other myna that occurs on the island, although in more rural areas, is Jungle Myna. This is somewhat intermediate between the other two. It has a smaller tuft at the base of the bill, dark grey underparts but somewhat browner upperparts. The bill is rich yellow, with a pale bluish base to the lower mandible, and the eye is also a rich yellow.

The hybrid shows a yellow bill which is paler toward the tip, and has a faint pinkish tinge to the base of the lower mandible. The iris is quite a rich golden yellow. The facial skin is more restricted than on Common, and is greyish-pink. The underparts are grey, like Crested, but the belly is white, like Common. The vent feathers are black with broad white fringes. Curiously, it has a whitish spot on the upper throat which is not shown by either species.

There is a vestigial tuft above the bill and the upper wing coverts are brownish. The flank feathers have fine pale edges, like Crested.

The bird bears a superficial resemblance to Jungle Myna, but the dark feathering on the vent rule out Jungle from the bird's parentage.

So, the question is, is this an isolated case, or does this spell bad news for the island population of Common Mynas? Only time will tell!

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