(CN) - The National Oceanic and Atmospheric Administration may expand the boundaries of two national sanctuaries off the California Coast.
The Gulf of the Farallones and Cordell Bank Marine Sanctuaries are federally protected marine areas off California's north-central coast. NOAA designated them as sanctuaries in the 1980s.
NOAA published a notice on Friday proposing an expansion of the areas north to Mendocino County and west to the edge of the Continental Shelf.
The expanded area would include the Point Arena upwelling center, which NOAA says "consistently produces the most intense upwelling in all of North America."
Upwelling is a phenomenon in which wind carries cool, more nutrient-rich water to warmer, nutrient-deprived waters.
"The sanctuaries are destination feeding areas for endangered blue whales and humpback whales, sharks, salmon, and seabirds like albatrosses and shearwaters that travel tens of thousands of miles," the agency wrote. "Food that results from the Point Arena upwelling center also supports the largest assemblage of breeding seabirds in the contiguous United States on the Farallon Islands."
The waters are also home to coral reefs, rockfish, salmon and Dungeness crab.
"The rich diversity and health of this thriving marine ecosystem depends on the cold nutrient rich source water originating from the Point Arena upwelling center," the agency wrote.
Advisory councils from both sanctuaries have discussed boundary expansion in the past, and in 2008 a joint management plan review determined that managers would facilitate an expansion process within five years.
The agency seeks public comments on the proposed expansion, which can be submitted until March 1, 2013.
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