Tag Archives: sargasso sea

How Do Phytoplankton Survive Scarcity of a Critical Nutrient?

New study up-ends conventional wisdom

Phytoplankton—tiny, photosynthetic organisms—are essential to life on Earth, supplying us with roughly half the oxygen we breathe.  Like all other life forms, phytoplankton require the element phosphorus to carry out critical cellular activity, but in some parts of the world’s ocean, P is in limited supply. How do phytoplankton survive when phosphorus is difficult to find? (more…)

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American Eels Return to Mountain Streams after Dam Removal

Shenandoah National Park, Va. – American eels are declining across their range but are showing indications of a population revival following the removal of a large dam in Virginia.

The removal of Embrey Dam on the Rappahannock River increased American eel numbers in headwater streams nearly 100 miles away, according to research just published by U.S. Geological Survey, U.S. Fish and Wildlife Service, and National Park Service researchers.

American eels undergo long-distance migrations from their ocean spawning grounds in the Sargasso Sea to freshwater streams along the Atlantic coast from northern South America to Greenland. Dams may slow or even stop upstream eel migrations.  However, prior to this research, little was known about American eel responses to dam removal. (more…)

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