Every year, billions of birds risk their lives flying south for the winter, an incredibly challenging journey that many do not survive. Those that do turn around and make an equally demanding trek back north during the spring season.
“Migration is magical,” Wild Birds Unlimited Chief Naturalist John Schaust said. “It’s hard to comprehend the amazingness of what these small birds do; the duration of their flight—sometimes up to 90 hours straight— at a rapid, consistent speed is an unbelievable undertaking.”
While the journey itself is already a seemingly insurmountable feat, migration is also replete with danger, Schaust said. It is estimated that about half of all migrating birds do not survive their combined trips north and south each year. “There are so many risks involved with migration,” Schaust explained, noting that birds stop over unfamiliar habitats on their route, giving way to a greater threat of predation. Tall buildings, hazardous weather and large bodies of water are additional challenges these creatures must navigate in their trek.
So why do birds do it, ultimately?
“When you look at the globe, there’s a larger land mass in the Northern Hemisphere than the Southern Hemisphere,” Schaust said. “With more land, birds can lay claim to a larger territory, which is better for nesting and provides them with more food resources and enough space to sufficiently avoid competition and predators.”
The number of daylight hours also increase the farther North birds locate themselves. A nesting bird at the equator has approximately two fewer hours of daylight per day to bring food to its young than it would have if it nested near Chicago. In Alaska, a Robin can make more than 30 percent more feeding trips to its nestlings per day than it could while nesting in Ohio. Its young grow faster and leave the nest earlier, thus shortening the dangerous nesting period by 2-3 days.
Before these birds can return to raise their families, they must navigate the treacherous endeavor that is migration. Beyond avoiding the numerous external threats, it is of great necessity for them to consistently replenish their fat supply for the duration of their journey.
“Fat is what fuels migration,” Schaust continued. “Some birds double their weight to prepare for their journeys. If they can’t replenish their fat along the way, they’re in trouble.”
This is where bird feeding hobbyists come in. Supplying bird feeders with high-fat foods does wonders for the health and energy of these winged travelers during the spring migration period.
“High-fat, high-protein food like Wild Birds Unlimited’s seasonal blends provide migratory birds with that critical food resource as they head further north,” Schaust said, mentioning that a number of birds also feed on insects, fruit and nectar, including his favorite backyard inhabitant during spring migration, the Oriole.
“Orioles are beautiful birds that love to feed on oranges, nectar and grape jelly,” he said. “Whether they're moving through or inhabiting a backyard for the summer season, they are constantly in need of energy sources to fuel their migration or nesting activities.
For bird feeding hobbyists, witnessing the impressive effects of a successful migration that helps to bring about a new generation of birds is awe-inspiring. Simply put, Schaust said, “Migration is an amazing feat fraught with hazards, yet the rewards are worth every bit of risk."