Kip’s Comments - September 30, 2025

Sep 30

How Do They Know?

Imagine so many birds - big and small, of many species - that fly north in the spring and then they disperse. Throughout the summer those birds nest, incubate and raise young, and then need to fly back south again before winter arrives. How do those birds - in this case yellow-rumped warblers - know when to depart their northern reaches and where to pause to rest and eat before continuing their journey? And how do so many birds synchronize their movements and gathering locations to join together in large numbers?

Early this morning I found probably hundreds of warblers flitting about in trees along the Wapsipinicon River. For so many to be congregated at the same spot is a mystery to me. Please - somebody explain the intricate details of migration since this process applies also to butterflies and other wildlife. Thank you!

While I was out I also documented my activities and the continuing onset of autumn.