Thursday, July 19, 2012

Common Murre Disturbance

Monday night I had the pleasure of volunteering to help out with murre research.  Actually I was interpreting to the public while the others watched them through the scopes, and when there weren't people there to talk to I took lots of pictures and watched the excitement through binoculars.  I love getting to talk to people so that was fun, although I felt bad that I was often asked questions I didn't have the answer to since I was completely new to murres (aside from the one introduction I had to them my first week, on June 20th's blog post at the bottom.)
Apparently I chose the most exciting time to come.  There was a constant string of disturbances the entire time I was there.  A disturbance was explained to me as an event where a larger bird comes in and scares murres away and sometimes tries to eat them (as in when a bald eagle will come to eat an adult, the others scatter, and sea gulls come in and snatch up all the eggs).  At this point the chicks had all hatched but were too small to fledge (leave the colony).
Instead of bald eagles though, it was juvenille California Brown Pelicans causing all the trouble that night (and could be still happening, which if it does, the rocks may be cleared by the end of the week).

The Pelicans came in and went through this infuriating (to me) routine of flapping their wings to scare away the adult murres, and at this point many of the chicks fell down to the water. All they seemed to be after was to steal whatever fish the parents had brought to feed their chick. When the murres got scared they would drop it and the pelican would eat it. Sometimes the pelicans would eat small chicks, and sea gulls being the opportunists they are rushed in to eat many chicks with the parents scared away. The pelicans were also seen swallowing a chick then spitting it back out then swallowing again and repeating until the chick was dead. I don’t know what the pelicans got out of this since they didn’t eat these chicks.
Juvenile California Brown Pelicans and Sea Gulls severely thinned out the Common Murre colony

The colony was thinned to a fraction of its original size that night. It was sad to watch. I also went down to the beach the next day and saw many dead chicks washed up. Apparently hundreds of them were further down on the beach.

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