A tiny GPS tracker attached to a European honey buzzard revealed an extraordinary feat of endurance that few humans could match. Over 42 days, the bird travelled more than 10,000 km from its wintering grounds in South Africa to its breeding habitat in Finland, crossing deserts, mountain ranges and numerous countries along the way. The journey, documented by researchers led by Finnish ornithologist Dr. Patrik Byholm as part of Project Honey Buzzard, offered an unprecedented glimpse into one of the world’s most remarkable migrations. The data showed not only where the bird travelled but also how it timed its flights, selected energy-efficient routes and adapted to changing landscapes and weather conditions.
How scientists tracked a European honey buzzard’s 10,000 km epic journey
Researchers fitted the European honey buzzard (Pernis apivorus) with a lightweight GPS satellite transmitter before it began its spring migration from southern Africa. Unlike traditional bird ringing, which relies on occasional recoveries of tagged birds, the transmitter continuously relayed precise location data, allowing scientists to monitor the bird’s movements in near real time.The tracking revealed that the buzzard travelled more than 10,000 km in just 42 days, averaging about 230 km each day. The GPS data recorded its altitude, flight speed, stopover locations and travel patterns, enabling researchers to study how the bird responded to changing weather conditions throughout its migration. Every new transmission added another piece to the puzzle of one of Europe’s least understood migratory birds.
The bird’s 10,000 km journey was guided by nature’s invisible highways
The European honey buzzard did not simply take the shortest path between South Africa and Finland. Instead, it followed an energy-efficient route through eastern Africa, the Nile Valley, the Middle East and Europe, carefully avoiding long stretches of open water whenever possible. While this added distance to the journey, it dramatically reduced the amount of energy needed to stay airborne.The reason lies in the bird’s flying technique. Honey buzzards are soaring raptors that depend on thermals, rising columns of warm air created when the Sun heats the ground. These invisible air currents allow the bird to spiral upwards before gliding for long distances without constantly flapping its wings. Thermals are abundant over land but scarce over large bodies of water, making sea crossings far more demanding. By linking together these natural “highways” in the sky and taking advantage of favourable winds, the buzzard completed its epic migration with remarkable efficiency.
One of nature’s most efficient long-distance travellers
The European honey buzzard undertakes this remarkable migration every year, breeding across much of Europe before spending the northern winter in tropical Africa. During its annual journey, it crosses an extraordinary variety of landscapes, including African savannahs, deserts, Mediterranean coastlines, mountain ranges and dense European forests.Despite travelling thousands of kilometres, the species is capable of returning to the same breeding territories with astonishing precision year after year. Scientists believe this extraordinary navigational ability depends on several natural cues, including Earth’s magnetic field, the Sun’s position, visual landmarks, favourable wind systems and an inherited instinct that is refined through experience.Unlike most birds of prey, the European honey buzzard has a highly specialised diet. It feeds primarily on the larvae of wasps and bees, using its slender head, dense facial feathers and powerful claws to dig into underground nests while protecting itself from stings.
What researchers learned from the GPS data
Beyond documenting an extraordinary journey, the GPS transmitter revealed how migratory birds make complex decisions throughout their travels. Researchers identified important stopover sites where the buzzard rested and replenished its energy before continuing north. These locations are often as critical to survival as the breeding and wintering grounds themselves.The tracking also demonstrated how closely migration is linked to weather. Rather than flying continuously, the bird adjusted its schedule according to wind direction, temperature and the strength of thermals. Strong tailwinds allowed it to travel much greater distances in a single day, while poor weather often forced it to pause until conditions improved. These findings explain why migratory birds frequently choose longer routes that are safer and more energy efficient instead of simply following the shortest path.
GPS tracking is transforming bird research
Modern GPS and satellite telemetry have revolutionised the study of bird migration by allowing scientists to follow birds across entire continents with unprecedented precision. Researchers can now identify critical feeding and resting sites, estimate survival rates, understand how migration timing changes from year to year and monitor how climate change is reshaping traditional migration routes.These insights have become increasingly valuable as habitat destruction, expanding infrastructure and shifting weather patterns threaten migratory birds worldwide. By identifying the landscapes that birds rely on most, scientists and conservationists can better protect international migration corridors that stretch across dozens of countries.
