Fall is almost upon us! This means that many animals will be migrating to their winter grounds. But why do some animals migrate?
Animals migrate in search of lands more suitable to their survival. This generally means warmer regions and higher food availability, though some animals also migrate for breeding purposes – such as salmon who migrate up rivers to escape ocean predators that might prey on their eggs – while others migrate in order to follow the rains – such as many animals in the African Savannah seeking to escape the seasonal drought.
Naturally, the change in seasons causes these locations to move throughout the year. In the fall, animals usually migrate south to escape the freezing temperatures that winter brings; while in the spring, animals move north to follow their food sources and escape the summer heat.
How do animals know where to go? Although it is poorly understood, animals use the magnetic field of the Earth in order to orient themselves North and South. Because the core of the Earth is made of metal (mostly iron) and also spinning extremely quickly, a magnetic field is created between the North and South Poles. Even though humans can’t see this magnetic field (which is what a compass is for), many animals are able to sense it. You could say that they have a sixth sense! Despite this, we still don’t understand how animals actually know that their destination will be better suited for them- yet paradoxically, they do it successfully every single year.
Tule Lake in Northern California is one nearby area that boasts a massive bird migration every fall and spring. Almost 500 different species of birds can be spotted at Tule Lake, many of them stopping over for some rest and relaxation during their colossal journey from their summer grounds in Alaska and Canada to their winter grounds in southern California and Mexico.
Throughout the fall, keep an eye out in the sky for flocks of birds migrating south! Can you identify what species of bird they are?
