This post
has been inspired by a flock of seventeen Hooded Plovers found recently on the
beach at Sailors Grave, East Cape, in the Cape Conran Coastal Park.
Hooded
Plovers are strikingly beautiful birds.
Please click on photos to enlarge.
Adult Hooded Plover – the sexes are similar. |
During the
breeding season Hooded Plover pairs occupy and vigorously defend breeding territories
on suitable sandy beaches. So, during the breeding season from August through
to January, we mostly see pairs or small family groups (two adults with between
one and three young).
Hooded
Plovers are mostly sedentary, however outside of the breeding season they can
sometimes form flocks, suggesting they do move at least short distances in order
to congregate. We recently found a small flock of seven birds at the Yerrung
River mouth and a few days later, on the beach at East Cape Conran, we found
seventeen birds feeding together. The largest flock reported by locals in the
past was a flock of 27 Hoodies on the Snowy River estuary. Apparently the south-west
WA sub-species, the Western Hooded Plover (Thinornis
cuculattus tregallasi), has been recorded in flocks of 100 birds or more.
A flock of 17 Hooded Plovers feeding together on the beach at Sailors Grave East Cape Conran. |
In South-East Australia we find the Eastern Hooded Plover (Thinornis cuculattus cuculattus) which has been separated from the Western Hooded Plover by the Great Australian Bight. This is no place for sand loving Hoodies where the Southern Ocean crashes into the 100 kilometre long Bunda Cliffs - http://headofbight.com.au/things-to-do/bunda-cliffs
The two
gene pools have varied slightly since separation with the Western Hooded Plovers
having a more extensive black mantle and unlike the strictly coastal eastern
birds, the western birds can be found on inland salt lakes where they can also
breed.
We enjoyed
observing the plovers and taking photos as they foraged in the surf zone and
some bathed and preened.
The
seventeen Hoodies comprised 12 adults and five sub adults raised during the
previous breeding season ranging from birds in juvenile plumage that fledged in
February or March 2017 and others approaching full adult plumage with streaky
heads that were possibly 7 to 8 months old.
One of the older immature Hooded Plovers. |
This bird is younger than the one above judging by the amount of black on the head. |
This is an even younger bird with a lot fewer black head feathers. |
This is a juvenile with no black feather development at all – it must have fledged in February or March 2017 towards the end of the last breeding season. |
There were two very young birds – I am not sure if this is the same bird as the one in the last photo above or the other very young one. |
A comparison photo showing the very young bird on the right and a slightly older bird. |
By
observing Hooded plovers in the months following the breeding season we can see
how successful the breeding season has been. For the flock at Conran we can
never know if the 12 adult birds formed 6 breeding pairs or which adults raised
which young however on average we can say the 12 adults and potentially 6 pairs
of birds have raised 5 young to a point where they are secure and self-sufficient.
A success rate of 0.83 young per pair. However, if we assume that at least 2 of
the adult birds did not breed then 5 pairs raised 1.0 chicks each.
Given
Hooded Plovers lay between 2 and 3 eggs, one successfully raised young per
breeding pair does not sound like a good outcome, however life for eggs and unfledged
young on an ocean beach is tough and the attrition rate is high. So 0.83 - 1.0
is probably a great result! Though we do need to keep in mind the Conran birds
live in relatively good habitat with much lower human impacts than say birds on
the coast nearer to Melbourne. Also the local area has long been baited for
foxes as part of the Southern Ark Project which is also a big plus for breeding
Hoodies.
One of the
adult birds had a strangely shaped head which was not due to feathers but an
underlying growth or skull deformity.
An adult Hooded Plover with oddly shaped head. |
The bulge on the head may be due to a recent growth or a birth defect? |
The above photo clearly shows the black mantle - it is larger than when seen in profile and as shown in bird guides. The Australian Bird Guide (Menkhorst et al) shows the Western Hooded Plovers with its extensive black mantle.
The Hoodies
were mostly feeding along the zone where the sea washed in and out, which was
well down the beach as it was near to low tide when we were there. We did see seven
of these birds briefly feeding at the upper limit of the sandy beach in the
shade of Coastal Banksia – many small holes in the sand showed there was plenty
of food in this location.
The following
four photos shows an adult Hooded Plover extracting and eating a sand worm.
A Hooded Plover plunges its bill into the wet sand. |
A sand worm is drawn out. |
The tasty morsel is being swallowed. |
The worm is almost gone. |
Having downed the worm the bird searches for another. |
Juvenile Hoodie bathing. |
A quick flap of the wings to remove water. |
The bath is followed by preening. |
Following their bath they gave vigorous wing beats to shake off the water. |
One bird is bathing and another is shaking water off its wings. |
Hooded Plovers are sedentary with some local movements outside of the breeding season. However, some birds may move further as evidenced by one adult bird among the seventeen at Cape Conran which had a black flag marked W0.
Adult Hooded Plover with flag W0. |
“W0 is a female on the move! She was banded
with her siblings at Nullica (a beach near Eden) on the 23/10/15 at 4 weeks
age. So she has moved approximately 165km south. Thanks for the sighting – that
is awesome to hear where she is.”
So W0 is a
female aged about 1 year and 10 months old from the south coast of NSW. With a
flag and subsequent sighting report we have added to the store of Hooded Plover
knowledge which is particularly important for a threatened species.
It was a
great joy and privilege in a beautiful setting on a sunny winter’s day to watch
seventeen Hoodies going about their business of living. However I could not
avoid the thought of their vulnerability and the threats they face. On a
positive note however the BirdLife Australia Beach Nesting Birds Project - http://birdlife.org.au/projects/beach-nesting-birds
- is providing a helping hand to ensure Hoodies survive. We owe the BNB project
staff and volunteers a debt of gratitude for the work they do.
Note:
The
taxonomy of Australian birds is undergoing considerable change.
The
scientific names quoted in this post are from BirdLife Australia Working List V2
(1).
Hooded Plover
|
Thinornis cucullatus
|
Eastern Hooded Plover
|
Thinornis cucullatus cucullatus
|
Western Hooded Plover
|
Thinornis cucullatus tregellasi
|
Previously,
as per the BirdLife Australia Working List V1.1, the species name for the
Hooded plover was rubricollis.
Hooded Plover
|
Thinornis rubricollis
|
Eastern
Hooded Plover
|
Thinornis
rubricollis rubricollis
|
Western
Hooded Plover
|
Thinornis
rubricollis tregellasi
|
For more
information about bird names and taxonomy see the BirdLife website here:
As a guide to
the names of Australian birds, both common and scientific, the BirdLife working
list V2 is recommended.
I note the recently
published “The Australian Bird Guide Menkhorst et al” has mainly used the
International Ornithological Congress IOC V5.4 (Gill and Donsker 2015) taxonomic
list which gives the Hooded Plover species name as cucullatus. Other earlier guides have used versions of Christidis
and Boles 2008 which use the species name rubricollis.
The
taxonomy and naming of Australian Birds is an interesting subject and fundamental
to understanding our birds, their histories and relationships. If you have a
copy of the new Menkhhorst et al guide I highly recommend reading the essay “A
guide for birders to the evolution and classification of Australian birds” by
Dr Leo Joseph, Australian National Wildlife Collection, CSIRO.
Also recommended
is Australian Bird Names, A Complete Guide, by Ian Fraser and Jeannie Gray.
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