Have you ever wondered, “Do Geese Fly?” It seems like a simple question, but it opens up a fascinating world of avian migration, endurance, and incredible journeys across vast distances. While geese are well-known for their long flights, the story of one particular swan, known as Stonker, truly highlights the remarkable capabilities of migratory birds.
Stonker wasn’t just any swan; he was a whooper swan, and a particularly famous one at that. As the largest documented individual of his species, Stonker was known for his annual migrations between Iceland and Scotland. These journeys, typically taking two to four days, involved flying over open ocean, a testament to the stamina and navigational skills of these birds. Sadly, Stonker disappeared during one such flight in 2001 and is presumed lost, especially considering his advanced age for a swan at the time.
What makes Stonker’s story particularly compelling is a documented incident during a migration in the 1990s. Equipped with a satellite transmitter for research purposes, Stonker encountered a severe gale during his journey south from Iceland. Swans, like many migratory birds, have a fascinating approach to navigation. Instead of directly compensating for crosswinds like airplanes, they fly a two-leg journey. They initially head in a no-wind direction towards their destination and then, upon reaching a certain point, turn into the wind to reach a recognizable landmark near their target.
During this particular flight, Stonker was flying west, south of Iceland, when unexpected northerly winds pushed him further south than intended. He then ran into gale-force winds blowing from the north-northeast. This pushed him about 80 miles southwest of Iceland’s coast, leaving him dangerously low on energy reserves. Realizing the peril, Stonker made a crucial decision: he turned directly into the headwind, heading north-northeast towards the southwest corner of Iceland at his maximum airspeed.
Imagine this: flying directly into gale-force winds for over four hours, making a ground speed of only about 19 miles per hour. Stonker flew with incredible determination, pushing himself to his absolute limit. Upon finally reaching landfall in Iceland, he was utterly exhausted, remaining stationary for a considerable time to recover. The toll on his body was immense. It’s estimated he burned off over 15 pounds of weight during this single flight, starting at nearly 29 pounds and arriving at a mere 13 pounds. He was estimated to be within just fifteen to thirty minutes of completely running out of energy when he reached safety.
This incredible feat of endurance provides insight into the physiology of bird migration. Migratory birds like swans and geese prepare for these long journeys by building up fat reserves. Initially, they burn fat for energy. However, as they deplete their fat stores and become lighter, they require less power to maintain flight. At this point, they begin to break down protein in their muscles, combining it with water to burn as fuel. The ultimate limitation is often dehydration. Birds essentially run out of water, becoming unable to continue burning muscle protein for energy.
Stonker’s story is a powerful reminder of the challenges and triumphs of bird migration. It highlights the incredible resilience, navigational skills, and physical capabilities of birds like swans and geese as they undertake these epic journeys. While we often ask “do geese fly?” the real question might be, “how do they endure such incredible flights?” The tale of Stonker the swan offers a glimpse into the answer, showcasing the sheer determination and remarkable adaptations that allow these creatures to traverse continents and oceans.
