OCEAN · FIELD GUIDE
The Record Leatherback — The Turtle That Crossed the Whole Pacific
Adelita proved a turtle's whole-ocean crossing could be tracked at all. This leatherback showed just how far one will go: most of the width of the largest ocean on Earth, and then back again. A reptile older than the dinosaurs, following jellyfish across the entire Pacific.
A reptile that crosses an ocean
The leatherback is the largest sea turtle in the world — over six feet long, with a leathery ridged back instead of a hard shell — and one of the oldest reptile lineages on the planet. It is also a deep diver and a long-distance ocean wanderer. Adelita (already in this fleet) proved in 1996 that a single turtle's ocean crossing could be tracked at all. This leatherback showed how far that kind of journey can go.
From an Indonesian beach to Oregon
A female leatherback hauled out at night on Jamursba-Medi beach in Papua, Indonesia, one of the last great western-Pacific nesting grounds, and laid her eggs. Researchers from NOAA Fisheries and WWF-Indonesia fitted her with a satellite tag to learn where this critically endangered population goes to feed.
Instead of staying in tropical seas, she struck out east across the entire Pacific to the cool, rich waters off the coast of Oregon — prime hunting for the jellyfish leatherbacks live on. Then she turned around and headed home, back west toward the Indonesian seas.
A record, and what ended it
By the time her tag fell silent she had been followed for 647 days over a minimum of 20,558 km (12,774 miles) — at the time, the longest migration ever recorded for any ocean-going vertebrate, and among the longest known for any marine animal. Because the signal simply ended, the map stops at her last fix on the way home; nothing is drawn beyond it.
Why it matters
Her trek settled where the western-Pacific leatherbacks go to feed, and put hard numbers on why the species is so exposed. A turtle that crosses the whole Pacific — twice — passes through the waters of many nations and many fishing fleets, which is exactly why this population is collapsing. Mapping these journeys is the first step toward protecting the places along them that matter most.
See it on the map
Switch on the Animal Journeys layer on the Ocean canvas to follow her crossing. The chevrons show her direction; the solid line is the trans-Pacific route her tag recorded, ending where the signal was lost. She joins Nicole the great white, Adelita the loggerhead, the record humpback, E7 the godwit and Phyllis the elephant seal — each one real and drawn from published, citable science.
Source: Dutton, P. H., Benson, S. R., & Hitipeuw, C., NOAA Fisheries Southwest Fisheries Science Center / WWF-Indonesia, reported in The State of the World's Sea Turtles (SWOT) and Chelonian Conservation and Biology 6(1):150–154 (2007), "Post-Nesting Migrations of Leatherback Turtles from Jamursba-Medi, Bird's Head Peninsula, Indonesia."
Frequently asked questions
How far did this leatherback travel?
She was tracked for 647 days over a minimum of 20,558 km (12,774 miles) — from her nesting beach at Jamursba-Medi in Papua, Indonesia, east across the Pacific to feeding grounds off Oregon, and back westward — before her satellite tag's signal was lost. At the time it was the longest migration ever recorded for any ocean-going vertebrate (Dutton, Benson & Hitipeuw, NOAA Fisheries / WWF-Indonesia, 2007).
Why did she cross the whole Pacific?
Leatherbacks nest on tropical beaches but feed in cooler, richer waters where jellyfish — their main prey — are abundant. The western-Pacific population that nests in Indonesia travels enormous distances to foraging grounds, including the cool waters off the US west coast. Her crossing confirmed that the leatherbacks seen off Oregon and California are the same animals that nest in Indonesia, an ocean apart.
What kind of turtle is a leatherback?
The leatherback (Dermochelys coriacea) is the largest sea turtle on Earth, growing to more than six feet long. Unlike other sea turtles it has no hard shell — instead a leathery, ridged back — and it is a remarkable deep diver, reaching depths of over 1,000 m. It is also one of the most ancient reptile lineages alive, and one of the most endangered.
Why does a journey this long matter for conservation?
A turtle that crosses the entire Pacific passes through the waters of many nations and many fishing fleets, where leatherbacks are killed as accidental bycatch. Knowing the route and the high-use areas along it — which large tracking studies have since mapped in detail — helps target protections to the places that matter most for a critically endangered, collapsing population.
Is the track on the map exactly the route she swam?
It is an honest schematic of the recorded route, not a claim of exact daily pings. The line follows the published trans-Pacific path from Jamursba-Medi to Oregon and back west, and simply stops where her tag's signal was lost on the return — nothing is drawn beyond that point. Every distance and duration shown is a sourced figure (Dutton, Benson & Hitipeuw, 2007).
SEE IT LIVE
Everything in this guide is on the live ocean map.