Wednesday, July 31, 2013

More Spotted Sandpiper Chicks

More Spotted Sandpiper Chicks - Actitis macularia

Now that I have some sense of what to look for, Spotted Sandpiper chicks are relatively easy to spot (pun intended). They blend in very well with either river-rock or with shore-side brush. Movement is what gives away their presence.
I watched this chick for about 15 minutes on a newly-created river-rock-surfaced bend in the Elbow River. On one side was a peaceful "lagoon" of sorts with minimal current. On the other side was a major arm of the river with a strong current. These chick swim well, but I doubted their ability to do well in the main river. I stayed a good distance away and moved to the left or right to determine how the chick might react to moving towards the side with the stronger current. The chick always moved in the opposite direction to me, except when close to the side with the stronger current. In this situation, the chick moved towards me along the shore, with the safety of the minimal current water close at hand. How might a chick determine whether the current is safe enough to enter? Perhaps the sound of the water triggers some inherent safety signal?

These chicks have very large feet and while on rocks, they routinely step high, as if to anticipate the rise, but they seem to commonly over-judge the obstacle. Perhaps their depth perception at this age is not yet fine tuned. 
Notice that there is a partial web (semipalmation) between only the first (outer) and second (middle) anterior digits. What advantage might this arrangement confer? The lack of full palmation implies that swimming is not the primary method of movement. 


Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.

Cornell University eBird. 2013.

Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.

Sibley David A. The Sibley Guide to Birds. Alfred A Knopf, Inc. New York. 2000.

Sibley David A. The Sibley Guide to Bird Life and Behavior. Alfred A Knopf, Inc. New York. 2001.

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