Robyn, if you have the Emu from 1996 you should take a look at the
appended paper. I'm sure I've seen a more recent study of Koels but can't
remember where. As Philip says your observations are very interesting.
In the last two weeks interactions between Koels have become frequent
here in inner Sydney - yesterday I saw/heard an apparently agonistic
interaction with I thought 2 male and 3 female birds present and perhaps
all calling. Interpreting the behaviour isn't easy though.
Andrew
Vocal behaviour of the Common Koel, Eudynamys scolopacea,
and implications for mating systems
Cecily J. Maller and Darryl N. Jones
Abstract
The Common Koel, Eudynamys scolopacea, is a migratory cuckoo that occurs
along the eastern coast of Australia. Its most conspicuous feature is
the loud and persistent calling of males heard throughout the breeding
season. Although the commonest vocalisation of the Koel, the Cooee
call, is well known, other vocalisations have not been described in
detail. Here we report on six vocalisations produced by adult birds,
including duetting. The rate of calling of male Koels was investigated
on two different scales: monthly over the breeding season, and hourly
during the day and night. Calling peaked both in the early and late
months of the breeding season, possibly associated with the availability
of host nests. During the day, calling rates were significantly higher
at dawn and dusk than at all other times of the day. Data collected on
trees inhabited by Koels showed that calling males favoured trees with
a particularly wide canopy and dense foliage; most often, these were
species of Ficus. We speculate that the Koel shares with other cuckoos
a basic breeding pattern based on male dominance interactions that lead
to polygyny but that the discovery of duetting strongly suggests the
possibility of short-term pair-bonding within this mating system.
EMU 101(2) 105 - 112
--------------------------------------------
Birding-Aus is now on the Web at
www.birding-aus.org
--------------------------------------------
To unsubscribe from this mailing list, send the message 'unsubscribe
birding-aus' (no quotes, no Subject line)
to
|
