The Common Goldeneye (Bucephala clangula) is a medium-sized sea duck that is found across the northern regions of Europe, Asia, and North America. The species is known for its striking black and white plumage and bright yellow eyes. One of the defining physical features of the Common Goldeneye is its wingspan. In this article, we will take an in-depth look at the wingspan of the Common Goldeneye. We will examine how wingspan is measured, look at average and extreme wingspans, and discuss how wingspan relates to flight and migration in this species.
What is Wingspan?
Wingspan refers to the distance between the tip of one wing to the tip of the other wing when a bird’s wings are fully outstretched. It is a common measurement used by ornithologists and bird watchers to quantify the size of a bird. The length of the wingspan is determined by measuring from the distal tip of the longest primary feather on one wing to the equivalent spot on the other wing.
Wingspan gives an indication of the size of a bird and also provides information about its flight capabilities. Longer wingspans allow for slower wing beats and more efficient soaring flight. Shorter wingspans are generally associated with species that require faster flapping flight. In addition to length, the shape and surface area of the wings also influence flight style and migratory habits.
Average Wingspan of the Common Goldeneye
Most sources estimate the average wingspan of the Common Goldeneye to be between 60-73 cm (24-29 inches). The common goldeneye is a medium-sized duck, so its wingspan falls in the middle range compared to larger and smaller duck species.
For example, the Mallard, a very common dabbling duck, has an average wingspan of 81-95 cm (32-37 inches). The Bufflehead, one of North America’s smallest diving ducks, has a wingspan of just 33-38 cm (13-15 inches).
Among scientific literature, the average wingspans reported for Common Goldeneyes include:
- 64.8 cm (males), 61.2 cm (females) – Johnsgard, 1978
- 67 cm (males), 65 cm (females) – Carboneras, 1992
- 73 cm (males), 70 cm (females) – Muller and Parr, 1998
Based on these sources, a reasonable estimate for the mean wingspan of a Common Goldeneye is 60-70 cm (24-28 inches). Males tend to have slightly longer wingspans than females, but there is considerable overlap between the sexes.
Extreme Wingspans
While the average provides a good basis, there is variation among individuals within a species. The extreme wingspans give us a sense of the possible range:
- Minimum reported wingspan: 53 cm (21 inches)
- Maximum reported wingspan: 80 cm (31 inches)
The maximum wingspan reported is believed to be from an exceptionally large male Common Goldeneye. The minimum is likely from a small juvenile or female. Wingspans at the extreme ends of this range would be considered unusual. The vast majority of Common Goldeneyes have a wingspan between 60-73 cm (24-29 inches).
Wingspan and Flight
The wingspan of the Common Goldeneye allows it to engage in two main types of flight – flapping flight for slower speeds and short distances, and bounding flight for faster, more sustained movement.
The medium length wings enable relatively quick takeoffs and maneuverability needed when flying through cluttered habitats. The wings also produce enough lift for the Common Goldeneye to fly at speeds averaging 64-80 km/hr (40-50 mph).
For migratory flight, the Common Goldeneye utilizes a bounding flight technique. This consists of flapping interspersed with glides, and allows the bird to maximize distance travel with efficient use of energy.
The Common Goldeneye’s wingspan gives it the versatility to both fly swiftly across large distances and nimbly navigate through crowded spaces near shorelines and wetlands. Its flight abilities are well-adapted to its mixed habitat range.
Wingspan and Migration
The Common Goldeneye has a broad range that includes populations in Europe, Asia, and North America. Northern breeding populations migrate south to overwinter, while more southern breeding birds may simply disperse shorter distances.
The Common Goldeneye’s medium wingspan enables non-stop migratory journeys of up to 4,600 km (2,800 miles). Some of the more impressive migrations include:
- Birds breeding in Iceland flying over 2,000 km nonstop to reach Western Europe
- Birds from Eastern Siberia migrating 4,000+ km to Japan and China
- North American birds flying up to 4,600 km from Alaska to the Great Lakes region
These marathon non-stop flights are aided by the Common Goldeneye’s efficient bounding flight technique. Their wings allow them to cover great distances over oceans, mountain ranges, and other inhospitable terrain.
Shorter-distance migrants may fly only 1,000 km between wintering and breeding grounds. But in all cases, the Common Goldeneye’s 60-70 cm wingspan provides the right balance of speed and stamina for long migrations.
Conclusion
In summary, the average wingspan of the Common Goldeneye is estimated to be 60-70 cm (24-28 inches). This places them in the medium size range for ducks. Their wings allow them to engage in both swift flapping flight and more energy efficient bounding flight. These dual flight modes give Common Goldeneyes the maneuverability and endurance to migrate long distances across much of the northern hemisphere. So while Common Goldeneyes may appear stocky out on a lake, their impressive wingspans power these small ducks on some of the most ambitious migrations in the avian world.
