Birds migration is a wonder of nature that sees them make perilous journeys across oceans, valleys, mountains and deserts to reach their breeding or wintering grounds. Their migratory journey involves many challenges including harsh weather conditions, predators, and exhaustion. Birds have evolved amazing navigational cues, including celestial navigation, visual landmarks, magnetic sensitivity and odor, to help them navigate accurately. Other survival strategies developed by birds include learning new skills, storing fat, and following favourable weather patterns. Every year, birds make incredible journeys, each using unique strategies to overcome the challenges of migration.
Birds migration is an extraordinary phenomenon that has amazed humans for centuries. Migratory birds travel thousands of miles every year, crossing oceans, valleys, mountains, and deserts to reach their breeding or wintering grounds. Some birds are known to fly over 20,000 km a year. Migration is a perilous journey that involves numerous challenges such as harsh weather conditions, predators, and exhaustion. However, birds have evolved amazing navigational and survival strategies that enable them to complete this journey successfully. In this article, we elucidate the wonders of bird migration, highlighting how they navigate, and survive.
Navigation
Migration is a long and complex journey that requires accurate navigation. Birds, just like humans, use many navigational cues to direct their movement. However, the cues that birds use are more fascinating and intricate than anything that humans have developed. Experts have identified that different species of birds incorporate different sensory cues or navigational tools to make their journey safer.
Celestial Navigation
Some birds, especially those that travel during the day, rely on celestial navigation. Birds can perceive subtle changes in the Earth’s magnetic field caused by the sun’s position, time of day, and the angle of the Earth’s axis. These electromagnetic changes enable them to adjust their path accordingly. By observing the position of the sun and stars, they can determine the direction, time of day, and even their location.
Visual Landmarks
Birds also use visual landmarks like rivers, mountains, coasts, and other significant geographical features to guide their movement. These geographical cues are particularly useful for nocturnal migrants like owls and nightjars that are unable to see the stars.
Magnetic Sensitivity
Many birds have magnetite, which enables them to sense the Earth’s magnetic field. They can determine their North-South orientation based on the intensity and direction of the magnetic field. For example, pigeons have been shown to rely on the Earth’s magnetic field to help them navigate. In addition, birds that migrate over the polar regions have been shown to use their ability to detect the Earth’s magnetic field to make their journey.
Odor
Odor, particularly with respect to homing pigeons, has also demonstrated to play a part in navigation. It is believed that homing pigeons can detect differences in the earth’s magnetic field based on differences in the scent of the terrain, and use these scents to guide their movement.
Survival
Apart from navigation, birds have evolved survival strategies that enable them to overcome the challenges they face during migration. These adaptations include learning new skills, storing fat, and following favorable weather patterns.
Learning New Skills
Many birds migrate long distances to breed or find food. They need to acquaint themselves with new environments, especially young birds for the first time. Young birds often follow older birds and learn how to navigate and feed. They can also learn their social and mating behaviors, particularly in species that breed in complex groups.
Storing Fat
A significant challenge faced by birds during migration is finding enough food to provide constant energy to complete their journey. Many species of birds tackle this by storing fat in their bodies to fuel their flight. Before embarking on a long journey, the birds feed heavily, sometimes doubling their normal weight. During the flight, they lose the stored energy gradually. Some species, such as the Bar-tailed godwit, can fly for eight days consecutively without stopping to feed.
Following Favorable Weather Patterns
Birds migrate during specific times of the year, usually at the onset of favorable weather conditions. This migration is often timed to take advantage of prevailing winds and weather patterns. For example, it is believed that the Honey buzzard, a bird of prey that migrates from Europe to Africa, waits for certain weather patterns to take advantage of thermals or updrafts to stay aloft for hours “surfing the thermals.”
FAQs
Q1. How do birds manage to store enough fat to undertake a long journey?
A: Many species of birds tackle this by storing fat in their bodies to fuel their flight. Before embarking on a long journey, the birds feed heavily, sometimes doubling their normal weight.
Q2. What navigational tools do birds use to find their way?
A: Birds incorporate different sensory cues or navigational tools to make their journey safer. These include celestial navigation, visual landmarks, magnetic sensitivity, and odor.
Q3. How do young birds learn skills for migration?
A: Young birds often follow older birds and learn how to navigate and feed. They can also learn their social and mating behaviors, particularly in species that breed in complex groups.
Q4. What challenges do birds face during migration?
A: During migration, birds face numerous challenges, including harsh weather conditions, predators, and exhaustion.
In conclusion, bird migration is a fascinating and awe-inspiring phenomenon that demonstrates the ingenuity and fortitude of nature. Every year, despite multiple challenges, birds make incredible journeys, with each species showing a unique strategy to overcome each challenge. We can learn a lot from these amazing creatures, and it is our responsibility to conserve the habitats that sustain them so that they continue to inspire us for years to come.
