Australian researchers from James Cook University have revealed why golden jacks, a commercially important fish, show a remarkable distribution across the Pacific and Indian oceans. The key discovery is that young golden jacks learn to cover long distances by hitchhiking with whale sharks. The findings were reported by the associated scientific institution and published in an area science journal.
Oceanographers from James Cook University map a range for gold jack populations that stretches from the east coast of Africa to the west coast of North America and from southern Japan down to northern Australia. This wide swath suggests that these fish can cross biogeographic barriers that would normally limit their spread.
The research team observed that juvenile golden jacks frequently travel in the company of whale sharks, the largest fish on the planet. Whale sharks migrate long distances and create routes that leave behind relatively empty waters. By riding the currents around these giant travelers, young jacks conserve energy and reach areas beyond the reach of their siblings and cousins.
The study also explores how ancient scientists might have uncovered similar clues by examining sea sponge habitats that host the DNA signatures of nearby fish. These observations help explain how golden jacks have achieved their expansive distribution across vast ocean basins, hinting at a natural hitchhiking strategy that combines behavior with large-scale marine movement. Attribution: James Cook University research team and collaborating ocean scientists.