Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Monday, April 01, 2013

Little Pied Cormorant - road kill

Graphic (not nasty) image warning

Every so often I post photos of dead birds, for scientific reasons.
I intend to do so today.
If this distresses you, please come back again another day.

The point of today's post is that one seldom finds Cormorants as road kill specimens. This is a once in a blue moon opportunity to see this bird up close.

Little Pied Cormorants are common enough birds, but one sees them either on a tree beside a creek or dam, or flying over, or else one sees the neck and the back only, because they swim very low in the water. There is good science behind their low level in the water, as their feathers are non-oily, to allow them to get wet, thus allowing them to sink in the water. Ducks have oily feathers, which repel water, and so trap air inside their layers of feathers, aiding the flotation of the birds. Cormorants are diving birds, (underwater swimmers) so flotation would hinder, rather than assist them.

Beak of Little Pied Cormorant - note the strong hook
which assists the bird to hold its fish prey.
Webbed foot of the Cormorant.
Left foot has "thumb" on inside
(same relative position as on our hands).
I was surprised to see how large the foot was.
The "little finger equivalent" is in fact very long.
That maximises the area of webbing, thus aiding propulsion.
Two Cormorants diving.
You can see their wings are closed,
and they propel themselves entirely by paddling
with their feet.
Hence the importance of maximising
the area of the webbing on their feet.
By contrast, Penguins flap their wings underwater -
They are "flying" through the water, not paddling.

Very fine belly feathers of the Cormorant.
White above the "vent" and black below.
Tail feathers are of an entirely different structure
They are stiff and veined.
Top side view of the Cormorant.
It is very long and narrow in shape,
compared to more commonly seen road killed birds
such as Magpies or Galahs.
And now for an image of a tiny parasite I found on the belly feathers of the Cormorant.

I checked the bird for parasites.
I was looking for "Flat Flies"which are common on many birds.
Instead I found numerous specimens of this parasite.
It was tiny. Maybe 1.5mm in length, with a pointed head.
It has 6 legs, so it is an insect, not a Mite (which have 8 legs).
So maybe it is a louse.
Check this image of an Avian Sucking Louse

No comments: