When Will The Robins Nest?

American robin on nest (photo by William Majoros on Wikimiedia Commons)

Spring is moving north and so are the robins.  This week a big wave arrived after Monday's snow.  Now that they're here, how soon will they nest?

Robins nest later the further north you go.  In 1974 Frances James and Hank Shugart were curious about the conditions that governed their nesting times throughout the U.S.  Using climate data and Cornell nest watch information from 8,544 robins' nests they developed a model that predicted when robins would nest in a particular region.(*)

The model shows that robins cue on weather.  Hatching is timed to occur when local humidity is 50% and temperatures are between 45 and 65 degrees Fahrenheit.  By April 23, Pittsburgh's highs and lows are exactly in that range so our birds are getting ready.  Here's what they're up to:

  • Robins spend 5-7 days building their first nest of the season. 
  • Egg laying begins 3-4 days after first nest completion.
  • Eggs are laid one per day for a clutch of 3-4 eggs.
  • Incubation lasts 12-14 days.

From nest building to hatching, the first nest takes 26 days. (Subsequent nests take less time.)

Our robins should be nest building right now except for one thing:  Do they have enough mud to begin construction?   Has the mud been frozen?

Watch the robins in your neighborhood to see what stage they're in.   Join Cornell Lab's Nest Watch program and your data can become the basis for studies like James' and Shugart's that broaden our knowledge of birds.


(Credits: photo by William Majoros on Wikimedia Commons.  Click on the image to see the original.
Today’s Tenth Page is inspired by page 260 of Ornithology by Frank B. Gill, portions of which are quoted(*) in this article.

5 thoughts on “When Will The Robins Nest?

  1. Kate,
    I just love to read your articles. They’re short, sweet, and very informative. I always seem to learn something new. Keep em coming!


    Art Schiavo
    Hershey, PA

  2. As a beginning birder I thought that I could have spied a barely discernible Varied Thrush in a dark wood early one spring. Years later I read that robins press mud into their nests using their chest and I have since seen wide muddy brown splotches or bands across robin red breasts in the spring. This solved my years long mystery. The dark band I thought could have been a field mark for the Varied Thrush was indeed a “muddy field” mark, that of a springtime American Robin.

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