Common Merganser

(Mergus merganser)

Fernhill Wetlands, Forest Grove, Washington County, Oregon, USA, 14 November 2005

On 9 December 2005 at Baskett Slough NWR in Polk County, Oregon, USA, I was fortunate enough to witness a feeding frenzy by a flock of Common Mergansers.  Common Mergansers are apparently quite competitive, as the photos below show.  These photos were taken over a 4 second span.

The female was clearly struggling with this big fish as she ran across the water in her attempt to swallow it.  One of her friends rushed over to "help".

How does one steal a fish from the mouth of a friend?

Several more male friends decided to see if they could help.  All but one female apparently want nothing to do with this party.

This is the last time the fish was seen.

With most of the males underwater, the other females arrive.

With the fish apparently working its way down her throat, the skilled hunter tries to catch her breath.  At this point, all of the males are underwater, and all of the females are above water.  Perhaps an indication of the social structure of Common Mergansers, or just chance?