• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Rusty Waters Seen Off Santa Cruz

Posted on: Thursday, 15 November 2007, 12:00 CST

By Tom Ragan

SANTA CRUZ -- The rusty brown water seen in area waters recently is something many scientists refer to as a "red tide" a catchall phrase used to describe seawater when it changes colors.

Some scientists say it's one of the most dramatic red tides in recent memory.

It started accumulating about 10 days ago, brought on, perhaps, by the recent rains. More scientifically known as an algal bloom, red tides and what causes them are the subject of speculation whether it's a change in the weather pattern, the result of fertilizer runoff after a hard rain or a certain amount of exposure to sunlight over time.

Last week, three samples of the rust-colored water were taken near the Santa Cruz and Capitola wharfs and in the vicinity of the Cement Ship at Seacliff State Beach, said Steve Peters, a water quality specialist with Santa Cruz County Environmental Health Services.

Detected within was "cochlodinium," a toxic organism often blamed for massive fish kills at fish farms in Japan but also capable of killing birds if, that is, they happen to eat infected fish that have fed off it.

"But it's not part of the oil spill in San Francisco," Peters said. "We've been getting calls from some people who think that the old Cement Ship is leaking oil or that there's been an oil spill near it. There hasn't been. It's just the color of the water." Peters said he's unsure whether the cochlodinium is connected to the deaths of dozens of sea birds over the weekend, and he'd rather a necropsy answer that question.

But the water is generally safe for humans, although swimming in red tides can irritate the skin and eyes.

Only in the early 1980s has Peters, a 20-year veteran in studying water quality, seen the ocean turn quite this red and that was in Moss Landing when he was catching infected shellfish and sending them to a state lab.

"The problem with these red tides is that we've just started studying them," said Peters, "and we don't have a whole lot of history, except for people's memories."

If there's anything that's certain, it's that the discoloration of the ocean water comes from the multitude of microscopic organisms that are always present in the Monterey Bay, one of the most active and productive bays in terms of the complexity of the food chain.

Then one day, or over a slow period of time, sometimes due to the light, sometimes due to storms, the organism population explodes.

For the most part it's the result of one organism, in this case cochlodinium, that has managed to dominate the other organisms, causing the change in color, Peters said.

Although the red tide is a common occurrence that has played out for millions of years, scientists have only recently begun to study the causes because it seems to be popping up more frequently, said Chris Scholin, a senior scientists who specializes in red tides at the Monterey Bay Aquarium Research Institute.

"If you ever scoop up water and look at it under a microscope, it's got all kinds of things in there," said Scholin. "They're wiggling and squiggling, and they're all part of the natural flora and fauna. And sometimes these things grow to greater abundance and that's when they're noticeable, and that's when the water begins to go from blue to not so blue."

Scholin, who specializes in making robotic instruments that detect the organisms and their toxins in the water, said other organisms that have proved dangerous to sea life include something called "pseudo nitzschia," which causes sea lions to become disoriented and birds to drop from the sky.

"The sea lions that consume the fish that have eaten this algae become delirious," he said. "It's what causes them sometimes to fall or to walk into the roadways or wander into parking lots and do strange things."

But none of those organisms have been found in the waters that have been tested, according to Peters.

E-mail Tom Ragan at tragan@santacruzsentinel.com.

Originally published by Tom Ragan , MEDIANEWS STAFF.

Source: Oakland Tribune

More News in this Category