And now, more fun from banding at Carpenter Nature Center on Friday. This time of year with odd molting patterns and juvenile/immature birds, some identification can be tricky. Some ids, with a little deduction, you can figure out pretty quick:
Check out this cardinal. It's mostly brown with lots of red patches--on the surface it shows characteristics of being both male and female. Is this bird a metrosexual? No! This is a male, hatched this summer and is now molting into his adult red plumage. When cardinals leave the nest, both males and females are brown. Half way through the summer, the males grow in all new feathers, ditching the brown and getting the red.
Check out how funky the face is. The feathers are brown like a female with hints of red. You can see the beginnings of the black that will surround his bill. And the bill itself is a whole hodge podge of colors. Young cardinals have black bills--that's one way you can tell a young cardinal from a female--adult cardinals have orange bills. This bill is definitely in transition from black to orange.
Here was another weird one. A female house finch with one pink feather on her breast. What was that about? I wondered if it was like female orioles. The older they get, the more they start to look like male orioles. However, clues on the bird said that it was a hatch year bird (hatched this spring) so I'm not sure why the one pink feather. Male house finches get their pink color from their diet--maybe this female has been eating like a male? Another mystery for another day.
And here we have a dreaded empidonax! Not the guy, but what is in his hand. That's Jim Fitzpatrick trying to figure out a small brown bird's identification. For people who don't know birds, there's a whole group of flycatchers called the empidonax flycatchers (willow flycatcher, alder flycatcher, etc) and they all pretty much look the same. In the spring when the birds are singing you have a chance to tell them apart by song. But in the fall when they are silent, it's not easy and empidonax flycatchers can bring the best birders to their knees in tears and frustration.
When you are banding birds, you use a very intense guide called the Identification Guide to North American Bird by Peter Pyle. It can tell you how to age and sex many species of birds by looking at subtle colors and feather shape and size. As we were trying to narrow the identification of the flycatcher in the above photo, we of course turned to Pyle. We were thinking it was between an alder flycatcher and a willow flycatcher.
Here is one equation offered by Pyle to determine the two--yes, that's what I wrote, an equation. Leave it to an ornithologist to use math to take all the fun out of birding:
"Formula I is (longest primary feather minus primary feather 6) minus (primary feather 5 minus primary feather 10), the latter value (p5 minus p10) being positive if p5 > p10 or negative if p10 > p5. The thin lines represent a buffer zone of 30% around the optimal equation (thick line on chart). Birds with measurements falling within the two thin lines should not be identified."
Yawn. Basically, this is saying to measure some of the flight feathers and an attached chart to determine if the bird is identifiable. It very well may not be identifiable at this time.
I brought the new Pete Dunne book Essential Field Guide Companion to see if there was any new insight to offer. There were a few hints but the end of the paragraph was tied up with this:
"But in the East, where Willow is more like Alder in all respects, the most helpful characteristic is often humility (on the part of the observer)."
Basically, you're just not going to know for sure. An excellent point, Pete, which garnered a knowing laugh from all the banders at the table.
Going back to Pyle we found this:
"Thus, successful identification of Alder and Willow flycatchers in the hand involves a synthesis of plumage characters, measurements, and wing morphology by age, sex, and geographic variation, and the use of a buffer zone in which birds should be left unidentified."
So, basically, Pyle is saying the same thing that Pete is saying. There are some things you can try, but some birds, you just aren't going to be able to identify.
The flycatcher in question was released without being banded. During the whole time, the flycatcher never struggled and sat patiently for the short time it was with us. If I were going to anthropomorphize (give human emotion to a bird's behavior) I would have said that it look resigned to not knowing quite what it was itself and could we please help it. We didn't want to keep the bird for an hour to try and guess the id and it's important to get the correct id to make sure the correct sized band is on the bird.
So take heart when you're having trouble figuring out a bird in the field. Some species are so complex, that they can't even be identified in the hand, six inches from your face.