I think you have hit the nail on the head. The main reason Red
Wattlebird are doing so well in most urban environments, and have
smaller territories, is due to a wider dietary requirements. Not only do
they feed on the nectar from a range of flower types, they also eat some
insects, berries and insect honeydew.
Little Wattlebirds are somewhat more restricted in their diet, using a
somewhat more specialized brush-tipped tongue to feed on nectar,
although they do feed on other foods such as insects, flowers, berries.
Their long tongue is specifically adapted to plants such as banksia and
grevillea.
Little Wattlebird are becoming more common. The main reason for this is
almost certainly related to the fact that people are planting more
banksia and grevillea species. In my yard alone I have planted 3 banksia
species (Banksia serrata, B. marginata, B. spinulosa) and a range of
grevillea and grevillea cultivar hybrids (Grevillea rosmarinifolia, G.
Robusta, G. Elegance, G. Honey Gem, G. Poorinda). Little Wattlebirds,
and a few others, such as Eastern Spinebill, love them. The ongoing
'drought' conditions have therefore favoured this species, mainly
because people are starting to plant the sort of plants that don't need
much watering. Australian city habitats are changing.
Tim Dolby
-----Original Message-----
From: Wendy
Sent: Saturday, 17 May 2008 2:01 PM
To: Tim Dolby;
Subject: (Urban) Red V Little Wattlebirds territory requirements
Hi Tim,
Thankyou for your interesting research on Song Thrushes.
I'm sure you need another distraction from book editing etc, so here is
one
I have wondered about.
The territory requirement of Song Thrushes (4ha) versus Blackbirds
(0.3ha)
reminds me of something I have observed and wondered about in 2 of out
local
urbanised natives - Red and Little Wattlebirds. Little Wattlebirds have
only
become resident in my area (Coburg, Melbourne) within the last 5-10
years.
Reds have been here all the time I've been here ~30yrs. I suspect these
2,
while occupying similar habitat niches, like the Song Thrush and
Blackbird,
have very different home territory requirements.
Reds live and breed very successfully (up to 3 or more broods a year,
often
with 2 young/brood fledging) in and around my and my neighbours garden.
While I have not studied it in detail, the pair appear to use an area of
only about 7 or so of our house blocks. They are also quite inventive
with
nest sites. For one or more seasons they nested in a small (~2m high)
Pencil
Pine in the 'garden' (~3sq m grass, 4 small Pencil Pines) of the huge
"palace" across the road. Food collecting occured elsewhere!
I am not sure if the Littles breed here, though the first arrivals
nearly
drove my then (nightshift working) partner to 'bird-icide', calling,
LOUDLY
all day for weeks, for a mate. There is little calling in recent seasons
so
I assume there is now a pair.
The next pair of Reds seem to live only one residential cross street
away.
Not sure where the next Little pair lives, but my feeling is, it is much
further away.
While their larger size may mean the Reds are better able to
harass/compete
with the Littles, I wonder if they are also better able to utilize the
strange variety of food on offer in an urban area like this. Apart from
their traditional diet of insects and nectar from my Eucs etc, the Reds
are
happy to eat my figs, apricots and other fruits - being very polite and
eating most of the one fruit, not sampling (damaging) all on the tree
like
some birds do. They also nectar feed from non-native trees in my
neighbours
garden such as camellias. I think I have also seen them eat dog food and
other unnatural things. The Reds can also tackle some impressive prey
items.
I often become aware of the first emergence of Greengrocer Cicadas, when
I
find the poor creature being dismembered and eaten by a Red Wattlebird
I suspect the Littles are more specific, less adventurous feeders. I see
them feeding in native blooms and hunting bite-sized insects. They seem
to
be more wary than the Reds and stay higher in the trees. I see Reds
hopping
about on the ground hunting and foraging (and dismembering cicadas!) -
never
Littles.
I also wonder if this territory size difference is only a phenomenon of
urban habitat. Or is it the same in the bush?
Any thoughts Tim, or others?
Wendy Moore
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