Tuesday, August 12, 2008

Identification

I had a visitor to my backyard yesterday. He (she?) was after the birds around my feeder. This is either an immature Sharp-shinned Hawk or an immature Cooper's Hawk. My vote is on the former because of the rounded head, the white eye-stripe, the square tail, and the cry he was giving. Unfortunately, I never saw the front of him, so I can't say whether or not the barring was heavily streaked. And because I didn't have a Cooper's and Sharp-shinned sitting side-by-side, I can't compare the size, length of tail, or flight pattern. Both are uncommon in the east but are common, especially in summer, in the west. Both are found around feeders because both feed on smaller birds. I have seen similar hawks in my neighborhood several times, but this is the first time I managed to get a photo.

I have been going crazy trying to identify things for this blog lately. I spent way more time than I should have on Sunday making sure that the photo of Corky I put up really was Corky. I think I have identified the other two whales in the show as Kasatka and Ulises. There are tons of websites devoted to these Orcas and many have pictures so that you can get to know them personally.

My previous blog entry about the native plants of George F Canyon has also caused identification problems. I posted a photo of what I thought was a Toyon, but my friend Yvetta corrected me and said it was a Mexican Elderberry. I hunted all over the web for a photo of the Toyon in bloom to compare the flowers to those of the elderberry, but couldn't find anything. There are lots of photos of the berries, but none of the flowers. Yvetta graciously sent me this photo of the Toyon in bloom from her extensive collection of plant photos.

You really need to see these side-by-side, so here is my photo again. The color difference is probably due to different lighting conditions and different cameras, but the elderberry has an all-white center and the Toyon has a dark center with different colors.


And last, I come to the problem of the little blue butterflies. I had no idea it was going to be so difficult to identify them. Apparently, there are many little blue butterflies and even the experts can't always tell them apart. My post about the El Segundo Blue Butterfly sent Yvetta off to find out the difference between the ESB and another butterfly called Acmon Blue. The expert (another Ann) sent us these photos and description of the ESB. Again you need to have them side-by-side to really tell them apart.


You can distinguish an Acmon from an El Segundo blue by the slightly larger size, a more fluid flight pattern that tends to be higher off the ground, more extensive orange coloration along the hind wing margin, and the even, light gray color of the ventral wings. I’ve attached an ESB image for you to compare your photos.

I was out surveying yesterday and it appears that the ESB flight season is winding down, but Acmon blues are in greater abundance. Acmon blues do well in a variety of settings and have a much longer flight season.

So there you have it. If you are confused, welcome to the club. The answer to all these problems is to have more experience in the field with these species and others that are hard to identify. So grab your hat, binoculars, and camera and let's go for a hike.


3 comments:

  1. I have never seen a bird of prey like that,I mean just sitting on a fence that is amazing. I also love the pictures of the butterflies I was once told a story about them which has always made me appreciate them.

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  2. Wow thats a good picture of a wild hawk! He looks hungry too :-)

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  3. Let's hear the story!

    Yes, it was amazing that he was just sitting there, and yes, he was hungry. It was a young hawk crying for its parent to bring food. In fact, it was his cries that attracted my attention. There was no sign of a parent but the birds at my feeder suddenly disappeared. Yvetta tells me that Sharp-shinned Hawks do not nest in my area and that this is most likely a Cooper's Hawk.

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