Whales Are Swimming Farther Than We Ever Realized

For decades, scientists have tracked migrating whales using satellite tags and flat maps. But it turns out these massive ocean travelers have been underestimated. A new study published in Ecology shows that whales may swim up to 20% farther than previously calculated, simply because traditional models failed to consider Earth’s curvature and the animals’ vertical diving behavior.

Not Just a Straight Line Across a Flat Map

“We’ve been looking at only part of the picture,” said Dr. Olaf Meynecke of Griffith University, a co-author of the international study. Traditional tracking methods record whales’ positions as latitude and longitude points on a 2D map. But whales move in three dimensions, plunging hundreds of meters below the ocean surface and navigating along Earth’s curved surface.

The researchers used data from the Whales & Climate Program’s longest continuous humpback whale track, following a female whale and her calf from Ecuador to Antarctic waters. On a flat map, the journey covered about 6,658 kilometers. But when researchers factored in average dive depths and the Earth’s ellipsoidal shape, the total distance swam jumped to 7,713 kilometers—an increase of 1,055 kilometers, or roughly 16%.

Why It Matters: Energy, Ecology, and Climate Change

This is more than a cartographic curiosity. As Dr. Meynecke explained, “If animals are expending more energy than previously estimated, we may be underestimating the ecological costs of migration and the impacts of environmental change.”

The findings could recalibrate how scientists estimate energy budgets, assess risks from climate change, and design conservation strategies. For whales migrating between South American breeding grounds and Antarctic feeding areas, this could mean swimming up to 14,000 kilometers per season—about seven times what the average human travels in a year.

Key Findings

• Standard map-based models underestimated whale movement by about 16%.
• Incorporating Earth’s curvature and dive depth added 1,055 kilometers to a single migration path.
• Energy expenditure and migration pressure may be significantly greater than assumed.

Flat Maps Don’t Capture a Round Earth

The new model combines geodesy (the science of Earth’s shape) with animal movement data. Instead of assuming a flat surface, it uses 3D spatial coordinates to calculate true distances. This method was tested not just on whales but also on terrestrial animals like mountain lions, whose rugged terrain also added complexity to their movement paths.

Lead author Thomas Meyer and colleagues developed two mathematically equivalent methods to account for curvature and elevation. One method re-projects animal GPS data onto a 3D ellipsoid model of Earth. The other applies correction factors to traditional map distances.

Whale Sleep? New Clues from the Data

Beyond travel distance, the whale data also offered a curious observation. Two long periods of low-speed movement—less than 0.2 kilometers per hour over 11 to 12 hours—hint at possible resting or sleeping behavior during migration. If confirmed, this could be the first documented instance of such behavior in migrating whales.

What Happens Next?

For scientists studying animal migration, this study is a wake-up call to move beyond flat models. As ocean temperatures rise and migratory routes shift, accurate energy cost models will be crucial for conservation.

As Dr. Meynecke put it, “These findings are more than just fascinating.” They are a reminder that even in the age of satellites, we still have much to learn about the journeys of Earth’s largest travelers.

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Journal: Ecology

DOI: 10.1002/ecy.70167

Title: Accounting for Earth’s curvature and elevation in animal movement modeling

Authors: Thomas H. Meyer, Tracy A. G. Rittenhouse, L. Mark Elbroch, Vladimir Pozdnyakov, Jun Yan, Chaoran Hu, Fernando Félix, Héctor M. Guzmán, Jan-Olaf Meynecke