About Ask the Expert Answers From the Robin Expert Special thanks to Journey North Science Writer Laura Erickson for providing her time and expertise in responding to your questions. Questions from Lewistown Junior High, MT spaulson@lewistown.k12.mt.us Q. Are the robins we see now at the first of spring, not the robins that are here during summer? A. Oddly, in many places the first robins to appear in spring are the ones that are going to stay through the summer. The farther north robins go, the later they migrate, leapfrogging robins on territory as they move north. Some northern races of robins also overwinter pretty far north, though they tend to skulk around inconspicuously compared to the real first robins of spring, who start singing as soon as they claim territories. Q. Do they lead the robins behind them in their journey north.? A. Nope! First come, first served! Each wave of robins has to get past the robins that have already claimed their territories, so each wave is actually a whole new group of leaders on the journey north. Q. Could it be that there are sub-species of robins? The first robins we see here always seem to be rounder, fluffy birds than the summer dwellers. A. Yes, there ARE subspecies of robins. HOWEVER, that's not the reason your summer birds look different than the first robins. When robins arrive, they are plumper partly because they spent the winter pigging out, and even more because of the cool weather in early spring. Beneath the smooth outer feathers that we see, robins have a thick layer of down feathers. When the weather is cool, their skin muscles make these down feather stand erect, providing big air pockets for insulation. This makes them look bigger, rounder, and fluffier in cool weather than they do in warm weather, when the down feathers lay flat. Also, by summer the birds have lost weight with the weighty responsibilities of territory defense and raising young. Museum Magnet School, MN lkindig@mms.stpaul.k12.mn.us Q. Why do some robins stay over the winter? (Marcel) A. If robins ALL stayed over the winter, they'd starve! But even though there isn't much food for robins in the winter, there is enough to support a few individuals even in cold places. Those individuals have to deal with more cold, but to make up for it, they may have a shorter distance to migrate come spring. What if a small flock tries to stick it out and suddenly runs out of food? Robins seem to have control over their migration, and can head south anytime they need to, even in the dead of winter when most migrants never migrate.. Q. How do robins get blue eggs? (Mari) A. The blue pigments in the shell are produced inside the female's body and secreted onto the forming shell as the egg moves down the egg tube, or oviduct. Why are the eggs blue? No one knows! Pure white eggs in an open nest are easy for predators to notice. The bluish tinge may blend in with sun-dappled leaves. Maybe blue is just their favorite color. Q. How do you tell which robins are overwintering and which are new robins? (Daniel) A. If they're singing or building a nest, they're DEFINITELY spring robins. In most northern places, winter robins eat berries, and spring robins eat worms, so you can be pretty sure it's a spring robin when you see it running on a lawn looking for worms. North Albany Elementary, OR bdaniels@8j.net Q. Are the robins on the west coast a different species than on the East coast? A. No, American Robins are the same species everywhere. But there IS a close relative that looks like a fancy robin, called the Varied Thrush, that lives in the coastal zone of Oregon north through the Pacific Northwest. You can see a photo here: Varied Thrush . Q. Have they done DNA testing? A. Ornithologists do two kinds of DNA testing on birds. One is to figure out if all the baby birds in a brood are from the same parents. With robins this usually, but not always, is the case. Scientists do another type of DNA testing to figure out which birds are related to which. This kind of testing has shown that the robin family, Turdidae, is not as closely related to a group of tiny birds, called kinglets, as scientists once believed. For a while scientists thought that kinglets and robins were in the same family, but DNA testing proved that they weren't. The Varied Thrush looks a lot like a robin, but DNA testing and other methods have shown that it's not only a different species, it's also in a different genus. Q. How fast can a robin fly at top speeds? Does this help in their survival? A. I don't know! Their normal flight speed is around 20-32 mph. The fastest robin speed that I could find in my research books was 36 mph. But I'm pretty sure I saw one going close to 50 mph when a hawk was chasing it one morning. I was next to a highway, so I guessed the bird's speed compared to the cars. Does their fastest flight help their survival? It sure does! Over the years, I've watched many hawks chase robins, and in most cases, the robins got away. Copyright 1999 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form