The geese are beginning their annual migration south from the mountains. Every day we see small flocks and hear their trademark HONK as they fly overhead on their way to warmer winter grounds.
Have you or your child ever wondered how a bird stays on track to their migration grounds? The need to migrate is triggered by changes in the amount of daylight, cooling temperatures, and food scarcity. So when a bird decides it is time to go, how do they make sure they are going in the right direction?
This is a mix of innate and learned behavior. Younger birds learn from the older birds which direction to go - but guess what? Once they know where they SHOULD be going, they rely on the Earth's magnetic fields to stay on the right path!
Scientists have discovered that birds have a special protein in their eyes called Cry4. This protein allows birds to SEE the magnetic fields of the Earth! The image below is a visual representation of how birds might see a magnetic field. No one is 100% sure how they see it, but this is what they think it might look like.
The magnetic field is used to help them navigate and stay on course.
Interestingly, even migratory birds in captivity will change their location in their habitat based on the time of year and the migration habits of their species.
Pretty cool, right? In some species of birds, there is more Cry4 protein around the time that migration is set to begin, so the fields may appear even more clearly for the birds.
I love watching the geese come and go with the seasons here in the mountains, and fall will forever hold a special place in my heart with the dry cool days and anticipation of winter and a season of exploring on skis ahead. Have a fantastic week!
Stay Wild and Free!