March Quiz: Answer

To refresh your memory, here is the photo from March’s Bird Quiz. It was taken in California during the month of March. Don’t read any further if you want one last chance to identify this bird.

3a

There are several obvious points about this bird.

  1. It’s floating in water. That narrows things down considerably. I could tell you that I took this photo from the Monterey pier, but that wouldn’t help very much—lots of birds don’t care if the water they’re swimming in is fresh or salty.
  2. It has red eyes. Pretty eerie—and diagnostic.
  3. It’s not a duck. That is not a duck bill.
  4. The bird is shaped like a lower case “h” (yes, I know it’s pointing the wrong way. Just pretend it’s swimming in the opposite direction). That humped back is helpful.

Since shape is one of the first impressions we get when we see a bird, that is where we’ll start. Of all the birds that might be floating in the water, we can eliminate most just by shape. Loons are long and ride much lower, with much of the body below the surface, while cormorants swim with just their neck sticking out. Herons stand upright, geese and swans have much longer necks, and all those “bobbing black blobs” such as petrels and fulmars don’t look anything like the bird in this photo. Pelicans and gulls are unmistakable. That leaves grebes.

The bill shape also rules out the birds I just listed above, again leaving grebes. So—let’s look at grebes.

There are six grebes commonly found in California. Western and Clark’s Grebes are large, with easily-recognized black and white markings. A Pied-billed Grebe has a much thicker bill, described as “stout” by Sibley. Red-necked Grebes don’t have a red eye. Also, while size is hard to estimate in this photo, they’re much larger than the two remaining species: Horned and Eared Grebes. Now we’ve narrowed the field down to two possibilities.

In March, grebes are just beginning to molt into their breeding plumage. Once they’re dressed for love, it’s very easy to tell them apart. I picked this photo because I wanted to give you more of a challenge. Even so, you can see the beginnings of gold appearing behind the eye. Hmmm….

With their winter markings so similar, it’s supposed to be more useful to look at the shape of the head. Horned Grebes tend to peak toward the back of the head, while Eared Grebes peak right above the eyes. With wind blowing the feathers, that’s a bit hard to tell on the bird in the photo. What else can we look at?

Let’s come back to the bill. Nonbreeding Horned Grebes have a bill sporting a white tip. The bill on Eared Grebes is all dark. I don’t see a white tip, do you?

Finally, Horned Grebes have an all-white cheek in winter, almost like a Western Grebe. Eared Grebes only have white below the eye, leaving the rest of the cheek dark—just like the bird in the photo. Yes, it’s an Eared Grebe.

Here’s a photo of a Horned Grebe, so you can compare.

Horned Grebe_Monterey-CA_LAH_6824_filtered

See the white tip on the beak? The large white area below the eye, that includes the entire cheek? Even though the bird is aimed slightly away from us, see how the head is peaked toward the back rather than right over the eye?

Now try your new skills. Which grebe? (Click on the photo and look at the url to see the answer.) That wasn’t so hard, was it?

Horned Grebe_Monterey-CA_LAH_7017

Eared Grebe_Monterey-CA_LAH_6815Eared Grebe_Monterey-CA_LAH_6831

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