Saturday, October 06, 2007

Migrating Silvereyes Return.

It's not often that Silvereyes get a mention on this blog, but a visit to the Goat Bluff area 3 days ago, prompted this mention.
A substantial number, perhaps the majority of Silvereyes, migrate to the Australian Mainland, some apparently getting as far as Queensland, an epic journey for a small bird (weighing in at around 10 grams). Many of what I assume are the non migrants, have already starting breeding, indeed for a month or more, so coming across substantial flocks of Silvereyes, suggests that these birds are the returning migrants.
I took the accompanying images of these birds, as they fed among the low coastal scr
ub. At first I assumed their interest was in the flowers, just as wintering flocks feed on the correas here, but close observation showed that they were eating small insects. In this few acres of heath, there were probably a hundred or more Silvereyes, erupting from the scrub as you passed by, with much "tanging", as they kept in touch with their neighbours.
Why only part of the Tasmanian Silvereyes migrate, and in particular, how they navigate, has been the subject of much research by Dr Ursula Munro, and you may find out more about that on the internet. At the Tasmanian end, I have had a peripheral role with Ursula and other researchers. Tasmanian Silvereyes are slightly larger than their Mainland cousins, and in the field they have noticeably darker chestnut flanks.

3 comments:

Birdfreak said...

What a gorgeous bird! Wonderful and interesting post, I would love to see one of those guys!

John & Shirley Tongue said...

Hi Alan,
We "stumbled" upon an Olive-backed Oriole in Wynyard last Friday.... apparently only the second or third record for the State. Unfortunately, we did not grab the camera in time for a shot. We plan to go back as soon as we can for another look.

mon@rch said...

I stumbled upon this also . . this is great! BRAVO