January 28, 2009

Lyngbya is growing problem

Published in the Crystal River Current on January 28, 2009.

Lyngbya [ling-bee-aah]

You see Lyngbya on the bottom of the water as it sleeps in winter time. It looks like clumps of wispy dark hair streaming in the current. Reach down and gently rub a piece between a finger and thumb, it feels slimy. Removing such dormant Lyngbya means it will not be there to bloom in the spring and summer.

As the sun's angle in the sky becomes high enough to penetrate the water with enough energy, Lyngbya begins to make chlorophyll. It will grow (bloom) while it finds in the water a “cocktail” of nitrogen, phosphorus, dissolved calcium, and a trace of iron. It has done this for millions of years, as one of the earliest life forms known. Spiking the cocktail with a mineral, for example, from fossil fuel combustion residues, causes a more vigorous bloom.

As it grows and needs more energy, it will rise in the water column to find more of the nutrient cocktail or more sunlight closer to the surface.

Later in the summer dense mats of Lyngbya rise to the surface, still having the slimy feel, but are green or brown, and are spread widely by wind and water currents. Heavy rains cause the mats to lose buoyancy and sink to the bottom where they grow again. Under these surface mats, huge gobs of rising mat look very much like cabbage soup.

Oxygen from the water is consumed so that fish, manatees and other critters move away. Wildlife activity diminishes where there is Lyngbya, and some water plants are smothered. As it decays it stinks, like rotten eggs.

Under a microscope a Lyngbya filament resembles a series of stacked pancake-like sacs of bacterium within an outer sheath. Baby filaments are poked out of an end of the sheath to form new colonies.

Nasty toxins are contained in the filaments which are released when the filament is broken, perhaps by a boat propeller, walking on it, or even when you sit down in your bathing costume crushing filaments that have found their way inside.

Next time I will tell you how the “cocktail” gets to be in the water.

Norman Hopkins. Director, Kings Bay Association, Director Amy H Remley Foundation Inc.