The background to our
recent visit to Lady Musgrave Island on the Great Barrier Reef (GBR) was given
in the previous post.
There were thousands
of Black Noddies breeding on Lady Musgrave Island. However long before reaching there we crossed
paths with Black Noddies out at sea as they moved about hunting for food.
Noddies are terns. Three
species are found in Australian waters, the Black Noddy (Anous minutus), Common Noddy (Anous
stolidus) and the much less common Lesser Noddy (Anous tenuirostris) which appears to be restricted to the Indian
Ocean with some birds found off the Western Australian coast.
Click on images to enlarge.
Black Noddy perched in a Pisonia tree on Lady Musgrave Island. |
Black Noddies take small
fish, plankton and jellyfish from the surface of the sea and while we passed
many birds flying alone out at sea, the feeding events we saw involved small to
large flocks of birds (I am not implying here that individual birds do not
forage alone).
Part of a Black Noddy flock feeding at sea. There are over 100 birds in this image which has captured about half the flock. |
At times the feeding seemed frenzied and in places it looked like a chaotic melee. |
Black Noddies are sedentary
and do not migrate after breeding. Their breeding is “aseasonal” (without
season, that is no rigid breeding schedule) with an increased likelihood of
breeding events in spring and autumn. They are colonial breeders and may have
one or two broods per year. They build substantial nests of leaves and seaweed,
cemented together with faeces, in trees and small shrubs and occasionally they nest
on the ground. Only one egg is laid per brood. Both sexes share incubation and the
care of young.
Given there is no
rigid breeding schedule, we were very fortunate to visit Lady Musgrave Island when
a large Black Noddy breeding event was underway. Thousands of nests were either
finished with birds sitting on eggs or still under construction as we saw many
birds gathering leaves and seaweed. Most of the nests were located in the
Pisonia trees however Pandanus Palms and Tournefortia trees (see previous post)
were also being used. There were dozens of nests in each tree.
Black Noddy on a nest of leaves and other material, held together with faeces. |
The price of nesting colonially and using faeces to cement nest materials is a good amount whitewash on feathers at times. I guess the next trip to sea to feed will wash off the mess! |
This piece of seaweed proved to be far too large and heavy to be lifted and carried to the nest. |
A piece of grass floating near the shoreline was of great interest to a number of Noddies still gathering nest material. |
I watched many attempts to pick up the grass, often with two or more birds competing. |
This bird managed to lift the grass a short distance above the water but eventually had to drop it as it was far too heavy. |
I found small groups
of Noddies, between 5 and 20 birds at times, on the beach sand picking up and
swallowing grit. At first I speculated that this was used to somehow help
digestion, however given the grit was calcareous (pulverised coral and shells)
perhaps it was to aid egg shell production, in which case they would have been
female birds! Small groups of Noddies also gathered on the beach to sun
themselves, often with an outstretched wing, this may have been a way of
removing parasites?
Noddy on the beach picking up shell grit. |
Photographing the
Noddies in flight at sea from a moving boat proved to be a great challenge partly
because they are small fast moving birds but also because their dark soft sooty
plumage makes autofocus difficult even under static conditions. In addition, on
the beach the tropical light was very harsh. Also the birds have predominantly near
black/dark brown plumage with a maximum contrast silver/white cap which makes
exposure difficult. Either the body is well exposed - in which case the white
cap is overexposed, or in the reverse case - the cap looks good but the body is rendered completely
black. However, I eventually managed to capture some acceptably exposed and in
focus images of Black Noddies in flight.
Black Noddy in flight. |
Bird with another leaf to add to the nest. |
Each tail feather ends with a point. |
I think I may have become a little obsessed with the challenge of capturing Black Noddy photos? |
It is hard to estimate
how many breeding Black Noddy pairs were on Lady Musgrave Island but the number
was easily in the thousands. It was relatively quiet while we were there with
birds finishing nests or sitting on eggs. Once the young hatch I imagine the
Pisonia jungle would be a very busy, noisy and smelly place.
Regarding the genus
names for Noddies, both scientific and common, Anous and Noddy respectively,
Fraser and Gray, “Australian Bird Names” provide the following explanations:
Anous ”stupid bird”, from Greek anous, foolish
(having no nous, in fact).
Noddy “is and
old English word meaning simpleton. It is presumed that insult was directed at
the bird for being trusting of marauding sailors in its breeding colonies.”
Clearly Noddies
evolved to breed colonially on remote offshore islands free from human and
other mainland predators. In addition, the birds are pelagic, spending their
lives at sea and rarely visiting mainland beaches so they did not come into
contact with people over the thousands of years of their evolution. It was not
until relatively recently that these birds encountered European sailors in
their breeding colonies. Today the names do appear to be insulting for a beautiful
trusting bird that has simply evolved that way. The names are certainly an
historic reflection of the minds and world view that existed in the early days
of European exploration and colonialism.
We found the Black
Noddies just as trusting today – they tolerate very close approach to their
nests which is a very special experience – thousands of years of evolution does
not change in a few short years.
In the next post (Part
3) I will cover other Tern species found on Lady Musgrave Island.
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