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Maybe it's time to get serious about Global Warming?
By Linda Hunter, Executive Director
From California to British Columbia, unusual weather patterns have disrupted the marine ecosystem. Normally, winds in the Pacific blow south along the coast in spring and summer, pushing warmer surface waters away from the shore and allowing colder water that is rich in nutrients to well up from the sea bottom, feeding the microscopic plants called phytoplankton. These are eaten by zooplankton, and in turn, many other species—from anchovies to cormorants to whales.
But this year the winds were extraordinarily weak and the cold water did not well up in spring as usual. Water temperatures soared to 7C above normal, which delighted bathers but caused the whole delicate system to collapse. The amount of phytoplankton crashed to a quarter of its usual level.
Seabirds are clearly distressed. On the Farallon Islands west of San Francisco, researchers this spring noted a steep decrease in nesting cormorants as well as a 90 percent drop in Cassin's auklets—the worst in more than 35 years of monitoring. The relatively rare birds, which feed mostly on krill, have since returned but came too late for successful breeding this year, said Jaime Jahnke, a researcher with the PRBO Conservation Science.
"We don't know what's going on," Jahnke said. "If this is the result of some kind of large climate phenomenon that we don't know about, it's important to document it and understand what's causing it."
More disturbingly, researchers have reported a sharp increase in dead birds washing up on the shores of California, Oregon and Washington.
Along Monterey Bay, there are four times as many dead birds such as Cassin's auklets, common murres and Brandt's cormorants than in most years, said Hannah Nevins, a marine scientist at Moss Landing Marine Laboratories.
"Basically, they're not finding enough food, and they use up the energy that's stored in their muscles, liver and body fat," Nevins said. "It's a level of mortality that's significantly above our long-term average over the last seven years."
On the Oregon and Washington coasts, volunteers found one dead Brandt's cormorant every 1.3 kilometers, compared with every 50 kilometers in most years, and logged a six fold increase in common murre mortality, Parrish said.
"The bottom has fallen out of the coastal food chain, and there's just not enough food out there," Parrish said. "We're seeing these stress signals. (The birds) are delaying breeding, they're abandoning their colonies and they're washing up on beaches. They're basically dying. They're way stressed out."
Fish appear to be feeling the effects, too. NOAA surveys show a 20 percent to 30 percent drop in juvenile salmon off the coasts of Oregon, Washington and British Columbia this June and July, compared with the average count over the previous six years.
And researchers counted the lowest number of juvenile rockfish in more than 20 years of monitoring in Central and Northern California—fewer than 100 caught between San Luis Obispo and Fort Bragg this year, compared with "several thousand" last year, said National Marine Fisheries Service biologist Keith Sakuma.
"This year was the worst year ever because the rockfish depend on the upwelling," Sakuma said.
The warming ocean temperatures are positive proof that climate change is happening. Warmer ocean waters put the entire marine food chain in jeopardy; plankton depend on cold waters to bloom, and other marine life depend on plankton for food. While global warming can seem to be an insurmountable problem, there is something you can do about it. Global warming is caused by emission of fossil fuels, and the average citizen can make a difference by making educated choices. We should all strive to reduce emissions of carbon dioxide and other greenhouse gases that cause global warming.
What can you do to combat global warming?
Basically, it all boils down to this: Don't use as much of the stuff that creates greenhouse gases.
To read more about how warming ocean temperatures affect marine life, click here:
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