I led wilderness canoe trips in the northeast for many years. The only pattern I detected among Common Mergansers was that canoe traffic flushes them downstream. Since they don't want to be seen returning to their shoreline nests, the birds either wait until later to sneak back or circle out of view to return. Another possible explanation for what you've observed is that the richest food sources are quite often at the mouth of the stream where it opens up and the current slows, while the sheltered roosts and nests are most likely upstream.
Gene Bullock
Poulsbo
----- Original Message -----
From: J & B Adamowski LaComa
To: tweeters
Sent: Thursday, January 05, 2006 8:27 PM
Subject: [Tweeters] local herring populations and bird behavior


Local Herring (baitfish) populations are at an all time low and the fish stocks are in real trouble. The birds that migrate here from the North that just do not seem to be showing up could be avoiding the area due to a lack of winter food supply. I believe there is a virus that has been running amuck and killing the native baitfish. There have been recent hatchery plantings of Herring but I am not sure what the net effect has been

Also just a question of Merganser habits. For years I have floated many rivers during all seasons. I am usually on the river at or near first light and off the water at or near o-dark-thirty. For as long as I remember I have watched Mergansers fly downstream in the morning and then pass me in the evening heading back upstream. Why is this? There is no difference in Summer/Fall/Winter or Spring either other than daylight. I never see them roost on land but usually just after the sun rises they get antsy and then the flock divides into smaller groups and takes off...only to return again that night for a slumber party. Do they have established hunting grounds and become territorial during the day and then forget this behavior at night for the safety in numbers gig? Do they just like to tour the river valleys and simply fly around just to tease me because I can't fly? I do not see them hunt the river either. They always fly to the same area and then fish that stretch only for the entire day. I do not know if the same birds are returning to the same spots each day as they are identical in plumage and there is no way to tell unless they were banded. Has anybody ever studied this or have any insights into this behavior?

Bryan
Shoreline, Wa.
jennandbryan at msn.com




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