Discussion of Challenge Question #7 Photo J. Brophy After you looked at A Robin’s Spring Mission, we asked you: If a lucky robin lives for 12 years and builds nests each summer except her first, how many nests might she build in her lifetime? What 3 things make her old nest unsafe for babies? After you looked at “A Robin’s Spring Mission,” you knew that a robin builds two or three nests each summer. If she built 2 per summer, her lifetime total would be 22 nests! If she built 3 per summer, it would be 33 nests in her lifetime. If you clicked on Build a Robin’s Nest, you discovered why an old nest is unsafe: even the cleanest robin family can't keep out mites, lice and flies. Once these critters get a head start, they can really multiply fast, making an old nest unsafe for a new batch of babies. The female might raise later broods in the same nest after remodeling it, or she may build a second nearby nest in 2 or 3 days. What You Said Steven, Emil, David and Brian from Iselin Middle School/Grade 7 came up with four other reasons that might make an old nest unsafe. Check out their good thinking! 1. Predators would know where her nest is located. 2. Humans could cut down the trees or ruin the environment. 3. Heavy winds and bad storms may knock the nest out of the tree. 4. The nest could unravel or come apart.   Copyright 1997- 2006 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form.