‘Dead Zone’ Growing, Killing Oregon’s Sea Crabs

‘Dead Zone’ Growing, Killing Oregon’s Sea Crabs

PORTLAND, OREGON — Commercial fishermen who work the coastline of Oregon have been shocked lately by huge swathes of crab carcasses washing out on the region’s beaches.

Scientists say the big die-offs are the result of oxygen starvation in so-called oceanic dead zones.

Here are the details: The Washington Post reports that scientists are raising the alarm about huge dead zones that are forming in waters near the Oregon coastline.

These dead zones are areas where oxygen in the seawater has become very depleted, causing all marine life to either move out quickly or die.

The fact that crabs and similar sea animals, unlike fish, are too slow to escape when such a phenomenon occurs, means that huge numbers of crabs can die when these dead zones form, and local fishermen have been reporting finding huge swathes of dead crabs that have washed up on Oregon beaches.

Scientists say dead zones occur as winds pick up in the spring and summer, driving cold water from the bottom of the ocean toward the surface.

That contributes to blooms of phytoplankton, which later die and sink to the ocean floor.

Bacteria then consume too much oxygen while decomposing the plankton.

Marine creatures like crabs, that can’t escape the low-oxygen zone, are left to die.

Scientists say they’ve been recording data that point to a very bad season of dead zones around Oregon later this year.

And all this points to crab fishermen pulling a lot of dead and inedible crabs from the bottom of the ocean in the coming years.

The Oregon State Legislature passed a bill this session allocating $1.9 million for research and monitoring of hypoxia zones in the ocean off the Oregon coastline.