Sunday, September 1, 2013

Confusing Fall Migrating Warblers

 Last night's north winds brought cooler weather and lots of migrating birds into the area.  This Chestnut Sided Warbler is headed south for the winter, where it wants to blend in and survive predators. So the bright colors of Spring are molted to these more muted colors. No chestnut sides now. We caught and banded this warbler this morning brfore releasing it.
 This Mourning warbler was another one that flew into the mist nets this morning. 

It is one of the confusing fall warblers whose muted migration colors make it look very similar to other warblers.

One of the only ways to separate this warbler from the Common Yellowthroat warbler in the fall is to compare the length of the feathers under the tail pictured below.
 The bird on the right is the Mourning warbler.  Its under tail yellow feathers (coverts) are quite a bit longer than the same feathers on the Common Yellowthroat on the left.  The length of these feathers helped us identify these birds. 

Banding birds requires a lot of very specific observations and measurements to be turned in with the banding data.

The rumpled feathers on this Red Start warbler's head are left over from the bander separating the feathers to see if the skull bone tissue was fully formed.  It wasn't, a confirmation that this bird was a nestling this summer.

The orange feathers under the wing indicate this is a male, and will have red and black feathers in the spring when he returns.

Warblers are beautiful birds, even without all the details.

1 comment:

  1. Great information and photos on Warblers. I often have a hard time telling them apart in the Fall. Thanks for sharing!