Feathered Vagabonds: Facts about Bird Migration
This article was written by Nature Canada guest blogger RuiLin Guo.
Migration is an astounding feat. And birds truly exemplify the wanderer’s spirit – over 4000 species are regular migrants, which is around 40% of all known bird species in the world!
Over the past several weeks, a myriad of birds made the airborne trek from their wintering grounds back to their breeding sites in Canada. Perhaps you’ve seen the spectacular diversity of species at birding hotspots like Point Pelee, or maybe you’ve simply enjoyed the extra birdsong around your home. With birds arriving predictably as clockwork year over year, it’s easy to forget how incredible an undertaking migration really is. As we wrap up this year’s spring migration season, here are some fascinating facts about feathered migrants from around the world:
The ultra marathon: The record for the longest migration ever goes to an elegant seabird, the Arctic tern (Sterna paradisaea). Their longest recorded journey was over 80,000 km – the equivalent of circling the earth three times! Arctic terns chase the sunshine, experiencing two summers as they travel from their breeding grounds in the Arctic circle to Antarctica.
The high flyers: Climbing Everest is a remarkable achievement, but what about flying over it? Bar-Headed Geese (Anser indicus) migrate clear over the Himalayan mountain range and reach altitudes of over 9 km above sea level, making them the world’s highest-flying migrants. The highest altitude ever though? That record goes to a poor Rüppell’s Griffon Vulture (Gyps rueppelli), which unfortunately got sucked into a jet engine at over 11k m above sea level!
The small but mighty: Hummingbirds may weigh no less than a nickel, but they make astounding long-distance journeys year after year. Ruby-throated Hummingbirds (Archilochus colubris) can fly 2100 km between Mexico’s Yucatan peninsula and the southeastern US every year, possibly travelling non-stop over the Gulf of Mexico! While not an overseas journey, the longest-distance hummingbird migrant is the Rufous Hummingbird (Selasphorus rufus) – one was recorded to have travelled a staggering 5600 km! Rufous Hummingbirds follow the blooming of flowering plants along the west coast, between Alaska and Mexico.
The non-stop action: The Bar-tailed Godwit (Limosa lapponica), a type of long-billed shorebird, is a true picture of endurance. They have the longest recorded non-stop flight of any bird, flying for 9 days over the Pacific Ocean without stopping for food or rest.
The big feast: Such intensive migratory feats require a lot of energy and many birds undergo something called hyperphagia, where they can more than double their weight! Each year before migration season, many birds feed intensely so their stored fat can then be used for energy while migrating.
The nomads: While most people think of migration as “going south for winter”, there are actually many types of migration, some of which are far less predictable. Nomadic birds such as waxwings (Bombycilla spp.) wander erratically within their range based on the availability of food and water, while irruptive migrants like Snowy Owls (Bubo scandiacus) undergo highly unpredictable migrations en-masse far outside their usual range.
These are just some examples of the incredible migrations undertaken by birds – truly among the greatest travellers of the animal kingdom. So the next time you hear the first robin’s song heralding spring or see geese flying in orderly V’s in autumn’s glow, maybe you’ll take a moment to reflect on their journeys.