Friday, July 13, 2012

Baby Arctic Terns

Arctic Terns can migrate up to 35,000 kilometers each year.  Why make such a long trip?  It probably is all about the babies. Don't expect to see tiny terns the minute you arrive at a tern colony. It takes time to find the little brown specks among the rocks and tall grass. It is interesting that only the Arctic Terns seemed to be breeding here. While there were Common Terns on site, there didn't seem to be any breeding activity going on among them.
One of the best ways to find the babies is to watch the behaviour of the adults. Both the male and female are active in incubating and caring for the small Arctic Terns.  These few pictures capture what is known as the "fish flight." This is not only a common sight when the Arctics are feeding their young, but it is also a part of the courtship prior to mating.  The male will get a fish and fly in low over a female.  If she shows any interest, the male will land and treat her to dinner.

Even though these are sea birds, the Arctic Terns don't like water.  They will quickly pluck a fish (capelin) out of the ocean staying as dry as possible.  This dislike for water can be observed at St. Vincent's as the Arctic Terns stayed well away from the water's edge.
The fluffy, little brown and white baby with a bright red bill and feet sits patiently waiting for the food to be delivered.

The adult arrives with a morsel, not a whole capelin. The little one emerges from the tall grass to eat, and as soon as the adult is gone, it retreats into the safety of cover.

This gets repeated over and over.  I don't know where this little bird kept putting the food, but it ate a lot! Within 23-25 days, this little guy will be able to fly, and the family will be off on their return trip to their warmer wintering grounds.

Now, my best guess around this immature tern is that it is a first-summer Arctic Tern. Sibley's provided pictures to help differentiate the juv. Common from the Arctic. What puzzles me about this bird is its black bill and its black legs.  I searched for about half an hour in an attempt to find a picture of one like this bird to no avail. Not only could I not find one like it, I couldn't find a description of one with black feet. It does seem that the bills of the Arctic Tern turn much darker during the winter. I guess the feet do too.

It is also interesting to see the chick has a bright red bill and red feet and then it change  to black during the first winter and stays that way until the second summer.  All this....just to confuse new birders, I'm sure!

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