Saturday, February 6, 2010

Are Robins REALLY harbingers of spring??

We’re getting into that time of year when people (understandably) are hopeful when they see Robins. They excitedly talk about seeing “the first Robin of spring”.

I live in the Midwest. In my neighborhood and nearby environs Robins are present year-round. But neighbors and other local folks still wax rhapsodic when they see a Robin at this time of year: “Spring is just around the corner!”

This dichotomy gives me more than a little cognitive disconnect. Robins are here year-round, and yet the “first Robin of spring” brings us joy. This prompted me to post a query on this topic to a birding e-mail list.

My question drew a great response from Barny Dunning, a wildlife ecologist at Purdue University. Professor Dunning at one time co-wrote a newspaper column illustrated by David Sibley that was distributed through the New York Times Syndicate. The first column in Professor Dunning’s series was about the true signs of spring and how the appearance of American Robins is NOT a good sign of spring anymore. Professor Dunning told me that this was one of his most popular columns.

Here’s a transcript of my e-mail Q&A with Professor Dunning (my questions are in bold):

1. Where did the "first robin of spring" tradition come from, if robins are present year round?

Decades ago American Robins were fully migratory in the northern part of the USA and so their arrival back on the breeding grounds was an early sign of spring. Their return is celebrated in many stories and poems, including one by Emily Dickinson. But as we planted many species of fruit-bearing shrubs in landscaping, and as winters grew milder, the robins began to winter successfully in areas further north each decade and now are common throughout the year in much (all?) of Indiana. Most interesting to me was that some of the stories and poems that celebrated the sight and song of the robin as a sign of spring were written by European authors including William Shakespeare. They were writing about the European Robin, a separate species that is only distantly related to our bird. But our bird is named after the European species, and happened in our early American history to have a similar annual cycle. So the poems translated well.

2. It's my impression that, when I was younger, robins weren't common in the winter. I can remember when "first robin of spring" meant something, and was a special event. Are robins more common now in the winter than they were 30-40 years ago? Or maybe I just wasn't paying as much attention back then? :-)

This process of increasing their range northward in the winter has been a gradual process taking decades. So 30-40 years ago they probably were less common. But I have only been here 15 years.

3. If robins are now more common in winter than they used to be back in the olden days, why do people still think of them as migratory birds that head south for the winter and return in the spring?

I live in Lafayette (IN) which is along the Wabash River. One factor playing a role here is local movement within the landscape. My impression in the fall is that large numbers of robins move to the river corridor and out of the town and suburban yards where they spend the summer. They move to the river corridor because it provides access to open water, shelter and fruit (especially honeysuckle, which is not a great source of food but is plentiful). So "the robins have left for the winter" is an easy impression. At this time of year (Jan - Feb) either of two things can happen. Either they deplete the fruit supplies in the river corridor and have to move out to find more, or there is a break in the cold weather. When the temperatures rise and the snow melts, the robins move back into the towns and start foraging in our yards. "Oh, the robins are back" is the obvious response, but in reality they never left.

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