Pollinator Study

Monday, September 21, 2015

They're BAAAACCK! Part 2

   

American Widgeons, loafing along the lake
A few days ago Nancy, my dad and I took a walk around Capitol Lake.  In the dog days of late summer, the lake is thick and turgid with clots of algae:  there are very few waterbirds.  But as the weather shifts into more cold & rain, and the days move into September, the waterbirds who winter over on this lake start to filter in.  And so it was a few days ago.

     We saw a few hundred American Widgeons.  These are small dabbling ducks, who feed in shallow water.  Their favorite feeding strategy is to upend themselves, dabbling with their bills along mucky bottoms and paddling with their feet to maintain their position.  From the surface what we humans see is the butt end; in widgeons the feathers under the tail are a bright white, so there is this marvelous big flash of white butt when they go ass over teakettle to feed.

    They are often the first wintering ducks to show up on the lake.  Part of this may be that Capitol lake is currently full of mats of bright green aquatic vegetation and this is the preferred winter food of widgeons.  

American Widgeons & friends
     They may stay here throughout the winter;  if Capitol Lake runs out of vegetation, they will leave the lake and look for other sources of winter food.  Sometimes they will leave the water and seek marshy green fields, finding their food there.  By next spring they will form pair bonds and return to their breeding habitat in wet tundra in Canada and up the Arctic circle in Alaska.    
     As we walk along the trail at Capitol Lake, we can’t usually see them:  the shrubs lining the path tend to block most of our views.  But we hear them:  they are pretty chatty to each other, making a distinctive “rubber ducky” kind of squeaky contact call.  They tend to stay together in groups, so the squeaking noises can be pronounced.
     There are reasons they hang out together:  as Nancy, Dad and I watched, a Bald Eagle swooped in over them.  Masses of screaming widgeons left the lake surface in a hurry, beating wings to avoid this predator.  The eagle made a leisurely circle around the panicking widgeons and went to a nearby perch, where it will keep an eye on the dinner table.  It didn’t catch any ducks on this pass, but my sense of  its behavior was that it was doing an exploratory flushing of the prey, watching for a weak or unwary duck.  Sooner or later, it will succeed.  And if the duck dinner doesn’t happen, there’s always salmon.

     When I see the American Widgeons begin to group on the lake, I am reminded that this is the
season of migration.  These ducks are showing me migration in action.  Let the fall season begin…

Janet
Resources:
•  All photos by Nancy Partlow

     

Saturday, September 5, 2015

They're BAAAAAACKKK...

King Salmon on the Deschutes estuary
     In early September in the Pacific NW we got some of the first deep soaking rains for several months.  A prolonged hot and dry series of months finally broke to an unseasonal fall storm, coming several weeks earlier than normal.

     Normally we moan about the rain, but nearly everyone I knew was profoundly grateful.  I could almost feel the trees drinking it up and the rain-washed leaves finally able to collect sunlight more efficiently. The amphibians started to move too: Glen and Nancy and I went out on a couple of very warm, rainy nights and watched tiny froglets leave the breeding pond for the winter woods.   Birds are starting to form winter guilds;  I watched chickadees, bushtits and nuthatches forage in a group, gleaning scale insects off of our Mock Orange.  The wheel of the season turns and this year it is rain that is turning that wheel.

     But that’s not all.

     For several weeks now, adult salmon have been coming in Puget Sound.  They head for the streams & rivers in which they were born and they wait for the right conditions to run the rivers.  Well, it turns out that rain triggers these movements:  the fresh rainwater cools the rivers, raises the water level and sends the strong unique scent of each river out into Puget Sound.  All these things make the migration possible.  So the salmon wait.

      Our local watershed is the Deschutes river and there are several types of salmon that are born in that river and return to it late in the summer.  There is a dam they have to pass through in order to get into the river, and they can only do so at high tide.  After the rains came this week, Nancy went to the dam and got these great pictures.  The salt water was unusually clear and almost teal-blue, no doubt because of the fresh rainwater coursing out of the dam.

     These are King (Chinook) salmon: the huge size, spotty blue-green backs and dark gums are distinctive to this species.  In late July into September, they leave the North Pacific ocean, head down the Straits of Juan de Fuca and into Puget Sound;   finally they head south to Olympia, to the Deschutes river where they were born.  A couple of hours before high tide, the dam closes, so they are forced to wait out the tidal cycle.  Today I went down at high tide and watched 60+ fish circling restlessly, trying to find a way through the dam and up into the impounded river.

     They don’t wait alone.  In the waters around the dam, Harbor Seals lurk.  Normally the fish can easily elude the seals, but in the enclosed waters near the dam, the seals are much more effective in catching them.  Here is a photo Nancy took: a Harbor Seal munching on its salmon catch, with a gull nearby hoping for scraps.

    Nor is it just the Harbor Seals that wait.  During the running of the salmon, there are always many people hanging over the rail, fascinated by this yearly event.

    Here are some sobering statistics:  a female salmon may lay as many as 4000 eggs, usually in a gravel bed nest or redd.  Of these eggs, maybe four will make it to adulthood and return to run the river to spawn.  What we see here are those rare survivors, returning once again to our waters, turning the wheel of life once again and bringing the promise of future generations.

Janet

Resources:  All photos by Nancy Partlow