Spring Phenology of Robins Watch for these events to occur in your backyard! Date Event   Over-wintering robins seen. Keep a tally and dates of your sightings all winter.   First male robin seen. (Report this to JN!)   Isotherm when first male robin seen. (See kow to measure the isotherm).   First wave of robins seen. We consider a "wave" to be three or more together in yard. When you see a wave, consider this a peak migration, not just an "early bird". (Report this to JN!)   Isotherm when first wave of robins seen.   First earthworm appears. (Report this to JN!)   First robin heard singing. (Means your resident robin has arrived and is establishing territory.) (Report this to JN!)   First female robin seen. (Look for lighter-colored feathers.)   First males seen in battle. They are fighting over territories.   Nest building begins. If you don't know exactly where a robin nest is located, you can watch for signs of nest building such as the male and female flying with nest materials, or the female with mud on breast. Both sexes gather nest materials, but usually only the female builds. She may begin nest building within a day or two after arriving. The nest usually takes 2-6 days to build.   Incubation of eggs underway. If you can't actually see the nest with the female sitting in it, you can assume she's incubating when you see her less often. (She spends about 50 minutes of every hour warming the eggs!)   Young hatch. (Usually about 12-14 days after last egg laid. Watch for adult flying with worm, rather than eating it. Both parents feed the babies. Broken pieces of blue eggshell on ground may be a sign of eggs hatching OR of a nest predator.)   First young fledge. About 9-16 days after eggs hatch the young leave the nest, or "fledge." Watch for flightless robins with a spotted breast on the ground or in low branches.   Young first take wing. The first 2-3 days after fledgling, the young are making their first clumsy flights. How long before they become good fliers?   Parents start nesting all over again. When suddenly only dad is feeding fledglings, it's a safe guess that mom's sitting on eggs again. Sometimes she uses the old nest, and sometimes she builds a brand new one. National Science Education Standards Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying. The details of this life cycle are different for different organisms. An organism's behavior patterns are related to the nature of that organism's environment. This Season Teachers Kids Orientation Registration Search Copyright 1997-2009 Journey North. All Rights Reserved. Questions or comments? Contact us.