Indeed that raises extra thoughts. It is only very recently that Crested Pigeons have inhabited this environment. The species was non-occurring and then rare
here until 1990 (GBS Report, as below), and the first breeding of the GBS was in year 8. Also historically the Pied Currawong was not a common breeder in our region, most migrating into the high country to breed. Just on geography, the (historical) natural
range of the Pied Currawong is also mostly exclusive of the (historical) natural range of the Crested Pigeons. Our habitat changes have brought them together. On that basis, the high predation interaction of these two is surely a very recent phenomenon. The
prey species has had little time to form any defences to the predator. They just breed a lot, which is not of itself odd for a dry country adapted species that presumably breeds when times are good, now finding itself in an environment of perpetual abundance.
Philip
Crested Pigeon Ocyphaps lophotes
This species has a broad Australian distribution, mostly occurring in the dry to semi-dry areas. It has spread considerably in recent years. It is conspicuous and approachable. It tends to occur in small groups on open
short grass where it feeds on seed. It will readily come into suburban gardens. Numbers vary only slightly through the year, from a minimum in November, then rises steadily to a peak in May and June. This may reflect the main breeding activity in Sept-Mar,
with a steady increase in the population as young birds enter the population up to May, followed by a decline as mortality or dispersion impacts and the population returns to a more stable level. Its long-term change may even be represented in the monthly
histogram. The fact that June abundance is higher than that of July (eleven months earlier), reflects the steady population increase of the species. Numbers have risen dramatically. There were only three observations of a total of four birds during the first
five years. For the first nine years there were 17 records from northern Canberra starting in Year 3, with 3 records from central Canberra starting in Year 1 and 12 records from southern Canberra starting in Year 6. So it took about six years for the species
to spread from its initial population in the northern and central suburbs to southern Canberra. The almost exponential rise took off in Year 10. From about Year 11 onwards the distribution has been generally uniform, though slightly more prevalent in northern
and southern suburbs than central ones. In Year 21 it ranked as the 13th most common species and occurred at 95% of sites. It appears to be stable and evening off now. Breeding records have increased dramatically, the first in Year 8, the next in Year 13,
then several each year. Few complete breeding events noted and the breeding period appears to be very broad with display at almost any time and actual activity at nest from late September to late March.
Graphs on page: 93, Rank: 45, Breeding Rank: 19, A = 0.59508, F = 39.91%, W = 33.7, R = 20.986%, G = 2.84.
From: Canberrabirds [
On Behalf Of Philip Veerman
Sent: Monday, 8 March, 2021 11:02 AM
To: 'Canberra birds'
Subject: Re: [Canberrabirds] Fatalities among Crested Pigeon young.
They are a frequent prey item of Pied Currawongs and no doubt other predators.
From: Canberrabirds [
On Behalf Of John Brannan
Sent: Monday, 8 March, 2021 9:19 AM
To: John Layton
Cc: Canberra birds
Subject: Re: [Canberrabirds] Fatalities among Crested Pigeon young.
Crested Pigeons regularly nest in trees at the bottom of our garden, and several times over the years I’ve come across chicks sitting on the ground below the nest, still unable to fly and apparently without the wit to find a hiding place.
I’ve found that lifting them up onto perches above the ground generally serves little purpose, as they end up back on the ground a short time later. Nonetheless, as you observe, they’re thriving in Canberra, so they’re obviously doing something right.
Florey
On 7 Mar 2021, at 4:52 pm, John Layton <> wrote:
Our postie stopped at the letter box on Friday morning and told me she’d just seen a “crow” prising a squashed baby bird off the bitumen.
“It was ghastly,” she said, “I nearly up-chucked my Weet-Bix.”
I stepped back in compliance with COVID19 distancing rules and explained that the “crow” was in fact an Australian Raven while she pointed to a small object on the road 20 metres away and resumed her mail run, Weet-Bix still on board.
I inspected the remains and identified them as being those of a fledgling Crested Pigeon. I returned to the house and five minutes later noticed that the raven was back tugging at the carcass, pulling it clear of the road surface and flying
away with it. This is the fifth dead C. P. chick I’ve found in our area during the last three weeks, often after heavy showers.
Curious to learn about fatalities among these youngsters I turned to HANZAB Vol 3 p. 909 viz, ... when 14- 19 days old, young begin to sit on twigs near nest during day and return to nest at
night; do this for 3-4 days then leave nest tree; spend next few days on ground, under shelter of dense growth. Young may roost on nest at night after fledging Presumably, during these early stages they are quite
vulnerable to predation, inclement weather and, if disturbed from shelter of dense growth, could move onto a nearby street with fatal consequences.
Nonetheless, the species appears to be doing very well in our area since I first noticed they were becoming common c. 1990.
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