There are large numbers of Banded Stilts at the WTP and based
on the strong colour of their breast bands they are moulting into breeding
plumage. This would seem to be expected at this time of year as most breeding
events listed in HANZAB have occurred between May and September.
What I have noticed though is that not only are the breast
bands gaining colour but that the birds have grown elongated feathers on their
backs that can be raised in display. When raised the elongated back feathers
give the birds a distinct ridge of erect feathers between the folded wings
and, when lowered, they form a mantle that spreads out over the folded wings.
It appears also that the chestnut breast band can be raised
from the body when the bird moves into a display position. This gives the
impression that the bird has a “chest plate” that is held out from the body.
I photographed one bird that seemed to be doing a brief
display but as I can find no written documentation of Banded Stilts using body
feathers as part of their courtship display I cannot be 100% sure. The whole
“display” event took about 4 seconds so the bird may have just been stretching,
however, the way the feathers were positioned during the event showed that both
breast and back feathers could be
raised as part of a courtship display.
I would expect that most of the courtship rituals and display
would be carried out on the breeding grounds so I am not sure that full
courtship displays will be seen at the WTP and similar locations but it would
be worth watching Banded Stilt flocks to see if the birds use both raised
breast and back feathers for courtship display.
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Rear view showing raised feathers |
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Rear view showing lowered feathers spread over wing feathers |
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1) Rear bird walks past with lowered feathers. Front bird has drawn its head up at start of "display" (stretching?) movement |
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2) Back feathers starting to rise |
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3) Back feathers raised further and neck feathers fluffing up. Breast feathers beginning to rise |
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4) Back feathers raised further. Head pulled back and neck feathers puffing out above chest band |
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5) Head moved forward with neck feathers well puffed out. Chest band raised clear from body. Back and rump feathers fluffed out |
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6) Neck coming back but body feathers still fluffed out |
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7) Front bird has lowered its feathers and both are feeding again |
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Bird preening showing back feathers raised from body |
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Birds at roost slept with back feathers spread out over wing feathers |
All text and photos © Jenny Spry
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