The last couple of years have been phenomenal for razor clamming along the Oregon and Washington Coasts. Record “Boon and Crockett” specimens have been showing up in people’s buckets, with giant four-inchers last year, and two-inchers this year. It was going to be another clam bounty in the Pacific Northwest. Was. Past tense. All that came to a grinding halt over the last week as officials have announced clamming is closed due to toxic acidity. The recommendations are clear for clam diggers: do not eat the clams. But what about SCUBA diving during an algae outbreak? Is it safe?
First, A Little Info
Whenever an algal bloom occurs, most people call it red tide. The algae, scientists call them phytoplankton, are microscopic, plant-like organisms that form dense patches near the water’s surface. These patches vary in color from green to brown to red. Another name for a red tide is “harmful algal bloom” or HAB. Red tides can cause the deaths of fish, coastal birds, marine mammals and other organisms.
If you eat food contaminated by domoic acid, which is the toxic substance found in the algal blooms, you can get sick. This includes mussels, clams, oysters, sardines, anchovies and the viscera of lobsters. It can cause permanent short-term memory loss, cardiac arrhythmias, and respiratory problems along with less severe symptoms as nausea, vomiting, diarrhea, and stomach cramps.
An interesting side note: the first recorded red tide occurred in what is now modern British Columbia in June, 1793. During Captain George Vancouver’s exploration of the area, men in his crew ate some mussels they had found. Almost immediately their lips and finger tips went numb. The numbness progressed until their arms and legs were paralyzed and nausea set in. Two centuries later the perpetrator was known: phytoplankton had contaminated the mussels, leading to the sickness of Vancouver’s men and the demise of one of his men.
But What About SCUBA?
Toxic algal blooms are harmless underwater, especially if you are diving offshore. Shore dives can be tougher. The stench can affect sensitive people and they’ll have trouble breathing. Red Tides have a large amount of dead critters, from the plankton itself to other organisms done in by the dearth of oxygen. As this biological matter decays, the smell gets worse and can cause problems for some people breathing it in on the beach. While this reduces visibility in the water, your actually diving in under the water should not be affected.
When diving through a red tide, you will experience low viz, stinky gear (you will have to wash everything thoroughly after you dive) and some respiratory irritation. It won’t damage your gear. As a rule, most people would probably advise against diving in a red tide, but from all the available research, it isn’t harmful.
Sources: scubaboard.com | http://aquaviews.net | capescuba.co.za | examiner.com