Tuesday, September 28, 2010

Walden and Sawhill Ponds - Rails and Yellowlegs

Saturday morning offered many more species than sparrows to observe. I saw three shorebird species of particular note.

The Sora:

A life bird for me, and one that is common in wetland habitats around the state. I am glad to have made its acquaintence and hope to see more.

Another was the Virginia Rail, which is actually a fairly close relative of the Sora. The two are the most common Small Rails and are in the family Rallidae along with the Large Rails, Moorhens and Coots. (The Sibley Guide to Birds). They share size, shape and feather coloring, but even in the poorly angled picture above the tell-tale long orange bill is visible, making the second bird a slam dunk Virginia Rail.

I also had two distinct looks at a single Greater Yellowlegs. A first sighting for me in 2010. This bird is tricky to distinguish from its smaller counterpart, the Lesser Yellowlegs. Apart from general size the bill is the best way to distinguish the two, or so I have read repeatedly. The Greater Yellowlegs has a longer bill that upturns slightly, while the lesser has a bill that is about the same length as its head, and remains straight. Of course I am still seeking a Lesser Yellowlegs, so I have yet to see the distinction for myself. Not having personal experience with both of these species I welcome feedback if my identification is off.

As always it is fun to see new birds. The Virginia Rail I had seen in Wyoming, but never before in Colorado, and had never photographed adequately for posting. While none of the shots are eye popping, they are ones that help me to confirm what I have seen in the field, and can be used in the future as a comparison.

On an unrelated note I wanted to share a book note for any Colorado Birding readers who may find themselves in a similar state of enthusiastic, if far from expert birding. I was pointed to "Colorado Birds - A Reference to their Distribution and Habitat" by a fellow Colorado birder after posing a question about arrival and departure dates for Winter Wrens in Boulder County. I looked through it at the library and immediately decided that it was a book I needed for my home reference. The book was written by Robert Andrews and Robert Righter and published by the Denver Museum of Natural History back in 1992. It provides an entry for each of Colorado's then 443 recorded species of birds, as well as a great front section dedicated to the various habitats and regions of the state. This book is not a field guide in any sense. Each species shows a map of its range in Colorado, charts of both seasonal occurance and elevation, and a write up of its rate of incidence in various portions of the state. This is going to be a great sanity check reference for me, and one that I would recommend to others as well. I couldn't find it being sold new through any of the major online retailers, but I got a great used copy for less than the original price after shipping. If nothing else go check to see if your local library has a copy. I couldn't see myself checking it out, but would swing by to check on something if I was really stuck.

2010 Count: 199
Lifetime: 243

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