Posted by Steve Kenney on June 25, 2003 at 12:46:58:
In Reply to: annual die off posted by Chris on June 24, 2003 at 20:35:44:
Chris:
"In recent years there has been an annual die off of sea mammals do to a build of of domoic acid in thier systems."
The last time "Red Tides" were discussed on this BBS after the Orange County Register article about Sea Lion illness it was stated that the Red Tide is a natural occurrence as if we should just shrug our shoulders and accept that nothing can be done to offset or improve upon this situation. After doing some reading on the subject I think there is room for argument. I had no idea this subject is so controversial and so much research has been done on it. The "Red Tide" is actually an overabundance of Dinoflagellate plankton which is a single cell organism that can rapidly reproduce both sexually and asexually given the right environment. Red Tides kill fish, cuts into spawn survival percentage, kills or sickens marine mammals, (Manatees have also become victims and Whales are also effected) and it works its way right up through the food chain to human PSP shellfish and ciguatera fish poisonings. In South Africa thousands of Lobsters marched out of the water starving for oxygen during a bloom. It must have been from a low level of dissolved oxygen in the water at that moment, just a guess.
Some researchers are pointing out that the occurrence of Red Tides is becoming more and more frequent due to human pollution sources which add fuel to the system in the form of nutrients(nitrogen, phosphorus, iron). IÕm leaning toward agreeing with this side of the argument. The plankton Dinoflagellate does occur naturally however two questions comes to mind.
Would the massive blooms that by ChrisÕs own admission is happening here recently happen here and elsewhere around the globe as often or with as much intensity if the plankton wasnÕt fueled by our constant dumping of nutrient sources that the plankton fed off of and then rapidly multiply to an out of proportion imbalance with the ecosystem?
Steve Kenney