Barbara Jones wrote:
> David Geering asks about coastal observations south of Jervis Bay.
> Here, between Merimbula and Eden, the Yellow-faced Honeyeaters usually
> begin passing through in a steady stream of 0000's from the end of
> April. We are still waiting! There have only been small (50+)
> groups,occasionally. Similarly the White-naped which accompany them
> in smaller numbers have been absent. Red Wattlebirds which also come
> a few weeks later in even greater numbers and over a wider path did
> not appear either. The hazard reduction burn-offs created large
> ammounts of dense smoke which did not get away quickly this year.
> Would that have re-routed the birds?
I'm not qualified to comment on what goes on in NSW re migrating
honeyeaters, but the matter of intra and inter regional movements of
honeyeaters (and lorikeets) is an interesting one. I've been looking at
20 years of presence/absence records I've collected from my notebooks of
birding the Geelong-Otway area (southwestern Victoria). Looking at the
region as a whole, it looks at first glance for eg that White-naped and
Yellow-faced Honeyeaters are present in numbers more or less year
round. However, breaking the region down into forest blocks or habitat
types begins to show patterns of intra-regional movement, corresponding
to flowering periods of favoured tree species. Which brings me to the
nature and predictability of flowering - many species flower fairly
reliably at a given time of year - some fail completely in some years -
others flower at odd times of year and occasionally poorly but twice a
year!
Comments on a couple of interesting tree species:
* Red Ironbark (Eucalyptus tricarpa) flowers quite reliably in
May-June around Geelong, but is variable in terms of the number of
trees which flower and/or the number of flowers produced by any
given tree. A real bird magnet (honeyeaters & lorikeets) in places
like Anglesea-Airey's Inlet and the Brisbane Ranges, and influences
both intra and inter regional bird movements.
* Yellow Gum (E. leucoxylon ssp connata) sometimes starts as soon as
April, but more usually from August to October. Most inter
regional (into the region) movements of Little and Musk Lorikeets
and Black-chinned Honeyeaters coincide with flowering of this
species.
* Mountain Grey Gum (E. cypellocarpa) flowers in late summer from
February-March, and would appear not to be a major bird magnet.
Perhaps in response to failure of flowering of other species out on
the plains and inland ranges, MGG in the eastern Otway Ranges
occasionally attracts small numbers of Little and Purple-crowned
Lorikeets (which are normally quite rare in the Otways).
So I guess what I'm getting at is that though there are fairly
reliable, annual, inter-regional movements when the scene is looked at
over a long period, there are years when these go awry, and the annual
movements themselves are inherently variable in terms of the number of
birds which take part and where they go. The intra-regional scene
shouldn't be underestimated either. Birds move within the region in
response to the availability of food. Birds can be siphoned off from
the big North-South movement if the local scene is having a good year
with tree flowering. The movement of White-naped/Yellow-faced
Honeyeaters north during the colder months is much more complicated than
it might look - they don't all go, and the ones that stay might stay for
different reasons in different years.
Cheers, Lawrie
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LAWRIE CONOLE
3 Gezireh Street, Pascoe Vale South,
Victoria 3044 AUSTRALIA. 37°44'27"S 144°56'17"E
Phone (03) 9354 2484; Mobile (0419) 588 993
E-mail: <>
Home page: http://www.users.bigpond.com/ocoineoil/
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