Monday, 29 September 2014

American Dipper


Dippers are small terrestrial birds, a little smaller than a Common Starling. They have adapted to an aquatic way of life, hunting for their insect food in fast flowing clear mountain streams.
I had seen the White-capped Dipper in Peru and was hoping to find the American Dipper in North America as we were visiting a number of national parks within the bird’s distribution range with plenty of suitable habitat – fast flowing crystal clear mountain streams.
White-capped Dipper searching for food in a fast flowing stream below Machu Picchu Peru.
There are five species of Dipper worldwide: White-capped and Rufous-throated (South America), Brown (Asia), White-throated (Europe, Middle East and Indian subcontinent and American Dipper found from Panama to Alaska and generally west of the Rocky Mountains. Dippers are not found in Australia. For more information on Dippers see: http://en.wikipedia.org/wiki/Dipper
During pauses while feeding, the Dipper bobs its whole body up and down, hence the name dipper. The birds are uncommon and solitary, occupying territories along suitable stretches of fast flowing clear streams.
What I find particularly interesting about these terrestrial birds is their adaption to an aquatic way of life. They have dense feathers and a large oil gland, which keeps the feathers water repellent and dry. Their nictitating eye membrane allows them to see under water. They have long legs with strong feet and sharp claws, which allows them to wade in fast flowing water and cling to rocks. Their short wings are used to swim under water in the pursuit of food and they can remain under water for quite some time.
I was keeping an eye out for Dippers in many suitable locations but it was not until late in our Yellowstone National Park trip that I found one on the Gardiner River about seven miles south of Mammoth Hot Springs near the north west corner of the park.
Gardiner River, Yellowstone National Park (photo G Hutchison)
American Dipper on Gardiner River, note the short tail and wing and long legs.
Jumping from a rock into the water to search for food.
Being small and a general brown and grey colour they are not easy to see against the background of a fast flowing mountain stream. The bird I found was actively feeding by working its way upstream into the late afternoon sun. Fortunately it was feeding on my side of the river and I was able to work my way upstream of the bird and wait for it to come by for photo opportunities.
These photos with captions describe the birds feeding activities.
Looking for food from above the water.
Wading in the water looking for food. From time to time the bird completely submerged
as it worked its way upstream.
Looking for food with head under water.
The eye is just visible under water as the bird continues its search for food
among stones and crevices of the rocky river bed.
Now and again the bird took a look at me to check I was not a threat.
The bird managed to capture a dozen or more food items over the 15 minutes or so I observed it. Each time it emerged with an insect it shook the water from it before it was swallowed.
The bird has another insect.
As far as I could see from the photos the insects all looked to be the same species
as they were the same colour and size.
I was pleased to find a Dipper, a small modest and inconspicuous inhabitant of Yellowstone National Park, and get some photos of it feeding.
Yellowstone is the oldest national park in the world (declared in 1872), a large and truly magnificent area with a diversity of breathtaking scenery and lots of large animals such as Bison, Elk, Mule Deer, Bighorn Sheep, Black and Grizzly Bears.  The park also has an awe inspiring volcanic history with many volcanic and active geothermal features, Old Faithful Geyser being the most well known one

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