Hi all,
There has also been a lot of comment on the current Yellow-faced Honeyeater
migration on the Canberra Birding email list (cog-l =
; Carol Probets has just alluded to this in her
email.
In Canberra, the movement of YFHE is predominantly west to east. There is
much movement out of the ranges to the west of Canberra, the birds
following the Murrumbidgee Corridor until they find apparently suitable
places to strike off in an easterly direction. Over the last couple of
years there have been some interesting observations of major migration
routes across the upper Shoalhaven valley, not only in autumn, but also as
the honeyeaters flock back westwards in spring. I put together an article
on this in Canberra Bird Notes last year - Vol 26(3).
It would appear, based on personal observations both last April (2001) and
also last weekend, that many many YFHE and also Red Wattlebirds end up at
Moruya South Heads. My current feeling is that the birds all head in an
easterly direction, following routes defined largely by topography and
vegetation. This takes many of them along the Deua and Moruya river Valleys
and they end up at the Heads where they hit the coast. There is much
swirling and milling about, the resident Little Wattlebirds doing a
valliant job of keeping them out of 'their' banksias, and I assume that the
YFHE and RWB then disperse along the coastal forests. I have always assumed
that they overwinter in the coastal forests, but it is possible that they
then get caught up in a northerly coastal migration...
To the north of Canberra, in the Lake George area, there has been talk of
YFHE heading in a NE direction, which would I guess, take them towards
Morton NP area. Whether most overwinter in the heathlands there or continue
north I don't know.
It seems clear that migration routes, at least on one level, are largely
determined by topography and vegatation cover. However, David Geering and
others have commented on the availability of flowering/food sources in
determining the location/migration routes of honeyeaters. It raises in my
mind the question of which of two factors, instinctive 'route following' or
food availability, plays the greater part in determining migration routes.
Is it known how much YFHE eat during migration? Are their routes determined
by food availability or do they follow instinctive and defined routes and
feed opportunistically as they go? How would honeyeaters migrating along
the ranges know that there are flowering Bloodwoods along the coast?
For such a common bird and common event there are still many many unknowns.
And lots of interest and fun trying to sort some of it out!
Harvey
.........................................................................
Dr Harvey D. Perkins :: Editor, :
School of Biochemistry & Molecular Biology:: Canberra Bird Notes, :
The Australian National University :: Journal of the Canberra :
Canberra, ACT 0200, Australia :: Ornithologists Group (COG):
ph +61 2 6125 2693; fax:+61 2 6125 0313 :: 42 Summerland Circuit, :
and: :: Kambah, ACT 2902 :
Pest Animal Control :: Ph: (02) 6231 8209 :
Cooperative Research Centre (PAC CRC) :: mobile: 043 886 9990 :
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