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Satellites, robot study sturgeon migration

May 3, 2013 — More than a century ago, an estimated 180,000 female Atlantic sturgeon arrived from the coast in the spring to spawn in the Delaware River and fishermen sought their caviar as a lucrative export to Europe. Overfishing contributed to steep population declines, however, and today numbers have dwindled to fewer than 300 adults.

Researchers at the University of Delaware and Delaware State University are using satellites, acoustic transmitters, an underwater robot and historical records to pinpoint the ocean conditions that the fish prefer during migrations — and potentially help fishermen avoid spots where they might unintentionally catch this endangered species.

“There are specific, observable waters in the ocean that we hypothesize are more associated with this species,” said Matthew Oliver, assistant professor of oceanography in UD’s College of Earth, Ocean, and Environment.

Oliver and graduate student Matt Breece compared prior years’ satellite data on ocean temperature and chlorophyll levels with locations where sturgeon were previously tracked migrating along the Mid-Atlantic coast. Based on patterns they found between the datasets, they are now using current satellite information to make rough daily predictions on where the sturgeon are migrating.

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