Unusually high sediment load from post-removal Elwha chokes seafloor kelp forests

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Elwha River Dam Removal by flickr user Paul Cooper (pecooper98362). All rights revert to originator.
Elwha River Dam Removal by flickr user Paul Cooper (pecooper98362). All rights revert to originator.

A not-entirely-unexpected result; indeed a return to what is by credible accounts the native state of the seafloor at the mouth of the Elwha:

The changes on the seabed are dramatic, from better than 80 to 90 percent coverage by kelp to an environment that is almost completely devoid of kelp. “It’s shocking,” Berry said. “It’s not subtle.”

It’s a similarly big change on the water surface, where great floating rafts of bull kelp have disappeared because the rocky substrate their hold fasts grab onto on the sea floor are smothered over in soft silt.

But it’s a back to the future type of transformation, experts think. Early maps show no kelp at the mouth of the Elwha, notes Jon Warrick of the USGS at Santa Cruz.

Read more here. Video of the denuded seafloor can be seen here.

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