A Wilder View: Why don't birds just stay south?

bird migration
Posted at 9:50 AM, Mar 15, 2023

MISSOULA - A sure sign of winter's end is the return of songbirds. Most of these birds are coming from comfortable places like the tropics or a warm beach, so why do they come back to Montana?

As spring arrives and winter fades our skies are abuzz with the sweet sound of chirping birds, as they embark on their spring migration.

But why are those birds leaving paradise in the south and heading back north to face cold temperatures and potential blizzards?

Winter is tough, especially for our feathered friends.

It takes a lot of energy just to stay warm and find food. So, it's no surprise that they fly south for the winter.

A study by the Cornell Lab of Ornithology found that between 2013 to 2017 2.6 billion birds died during fall and spring migrations -- proving migration is pretty dang risky for birds.

So why not just stay where the sun is always warm, and you don’t have to worry about any blizzards?

For birds living in the tropics isn’t sipping on a pina colada and taking in the sun. What may sound like paradise is really a fierce competition over resources.

There's an endless battle over food.

Not only are birds competing over resources with the naive bird species, but they're also fighting over it with the millions of birds that planned their winter vacation there too.

The hot and humid environments also serve as the world’s finest petri dish, suitable for an abundance of infectious diseases and parasites.

So as it turns out, there are some real advantages to making the trip back north.

Spring migrants time their return to coincide with an enormous supply of food.

Seasonal change is like a reliable clockwork mechanism that operates on our planet, offering dependable resources.

It's like the ultimate all-you-can-eat buffet!

As plants and animals in the north begin to bloom and reproduce, there's an explosion of seeds, fruits, and insects for the taking.

It's a springtime feast that's worth the long journey for these intrepid travelers.

So, migrating birds are simply following the trail of this natural abundance. Raising chicks is no small feat.

Breeding in the heat of the tropics brings a whole new set of challenges for the success of eggs and chicks.

By migrating north, these smart species are moving to a more temperate climate to raise their delicate chicks.

With cooler temperatures, they can focus on the important work of feeding and caring for their little ones.

At the equator, day length doesn’t change too much but in the north, during the summer months days get longer and longer.

And longer summer days in the north mean more time to gather food and feed hungry mouths.

It's all about balance, and each species must weigh the risks and benefits of migration.

Migration is a magical spectacle and according to the Smithsonian, the top five best places in the U.S. to witness these mass migrations during the spring are Rio Grande Valley, Texas Delaware Bay Great Lakes Central Park, New York City Point Reyes National Seashore, California.

But as our planet changes, so too do the habits of our animal friends.

Some species are arriving earlier than they used to, while others are changing their migration patterns entirely.

So, who knows what the future holds for our migrating friends?

One thing's for sure — the only constant in life is change.