Thursday, February 25, 2010

The Great Cormorant

Fishermen despise them, for they are in competition for the same food.

Regardless of that, lets take a close up look at these incredible fish catchers. A very northern species, the Great Cormorant is a winter over bird in the Norwalk Islands and the Connecticut Coast, during the warmer months this bird would be found in the Canadian Maritime and further north.

Lets take a up close look at this bird, first and foremost is the incredible hook at the end of it's upper mandible.

To think of this as a fish hook, is correct, these birds are fish eaters and this hook aids them in holding on to their catch, until they surface and than swallow their prey whole. Note the top of the upper mandible, above the hook, there appears to be fuzzy white shavings, this is the Rhamphotheca peeling off before renewing itself. (sort of like humans growing fingernails, this peeling and renewal would also explain seasonal bill coloration changes in many bird species)

Next, let's follow the white coloration from it's throat, through it's malar to it's cheek, following next to it's blue eyes and mosaic eye ring, Below the eyes is a spectacular orange area, giving way to a mirage of orange based colors where it reaches the lower mandible.

As we follow the back of the head (nape) note the crest that is showing in these pictures.

This crest is quite different than that of the Double-crested Cormorant
which displays two side by side V shaped crest on its crown during mating season.

These birds are very cautious and are not easily approached, in fact the half dozen winter over residents in the islands are totally unapproachable this winter, any closer than a few hundred yards and they are off.

Reading the CT BIRD postings the last week or so, it seems as though they have more to worry about than just fisherman shooting them, Bald Eagles have taken a liking to them. Their nestlings are being raided by juvenile Bald Eagles up north, and the eagles have been hitting the adults on the Connecticut River this winter. I'm sure this is also happening elsewhere.

Let's see how or if they adapt to these new pressure's.

Note: I was able to capture the above photos by boat from a very accommodating bird hanging out on a piling in one of the Norwalk Marinas most of last winter. This otherwise is not normal.


A good look at the white hip patch during take off


The birds body is almost underwater as it swims.




One small step for man, one giant step for a Cormorant!




2 comments:

  1. I'm sold on this blog! What a great idea and interesting detail on the Norwalk Islands wildlife, great photos.

    The Cormorants are certainly more plentiful than years before. At one time you could land on the northern part of Goose Is, during the summer, but now it has been taken over by nesting Gulls and Cormorants.
    David Park

    ReplyDelete
  2. I've been following the bird life of the islands for a number of years, the Goose island site is incredible, the gulls are already setting up their nesting areas out there. We should see the first few Double-creasted Cormorants on this island in about three weeks or so, those numbers expand fast don't they?
    Thanks for the complement, I'm glad you are enjoying the site.

    ReplyDelete