Hi friends – Cornelius’ friend, the white-throated sparrow is here. Thanks for coming back to read more of our blog series! Today I will be sharing fun facts about my hibernation migration.
While I love visiting with Cornelius, I don’t live in the park year-round. Instead, I’m just here for a winter trip. I spend most of the year in Canada and northern New England, where I nest in eastern hardwood forests.
Later in the autumn season, it becomes harder for me to find seeds. As a result, I must migrate south in order to find food to survive the harsh winter weather!
I’m five years old, and so I’ve been migrating for the last five years as well. Because I’ve already made the journey, I know where to go and take off in late September or October. Younger birds don’t have that knowledge yet, so they typically leave a little bit later.
We migrate at night because we can avoid predators and have time to eat during the day. The more I eat, the more fat reserves I can store. Stored fat serves as fuel – it is converted to energy to power my flight muscles. Once we get to a good rest stop, we hang around for several weeks eating and resting before finishing migration.
We know when to start migration based on the amount of daylight each day. As the days get shorter, the change in light triggers the parts of our brain that tell us to migrate. Once we are on our way, we know which way to fly thanks to iron particles in our eyes that react to the Earth’s magnetic fields. On clear nights, the stars help keep us on course, but we can use our internal compass even when the weather is poor.
Once at our wintering grounds in the eastern United States, we spend the winter foraging for seeds and berries in flocks with resident birds like chickadees and titmice. In the park, we can often be found in the shrubs along the Industrial Trail and the Sequoia Trail. Be sure to stop by and say hi!
Thanks for reading my blog! Stay tuned for more posts. See you at the Grist Mill!