It is, I am afraid, a fact of life that algae usually only attract the media’s attention when they are a problem. Yesterday’s newspapers contained a good example of this, describing the masses of the brown seaweed Sargassum that have washed up on Caribbean and Latin American coastlines, disrupting the tourist industry. Sargassum is a natural part of the for the Sargassum is an interesting organism, living a predominately planktonic (floating) existence rather than living in the coastal zone, like most other seaweeds. There is a region of the western Atlantic that has been named the “Sargasso Sea” as Sargassum is particularly abundant here. The Sargasso Sea is a region of relatively still water in the midst of rotating ocean currents (the marine equivalent of the eye of a hurricane) and the Sargassum proliferates here, hosting a unique ecosystem of its own in the middle of the ocean. It is from here that the larvae of eels start their long journey s across the oceans to our rivers, and to which the adult eels will, in time, return to spawn.
Although we have known about the Sargasso Sea for a long time (it was first named by Christopher Columbus), the arrival of such large quantities of Sargassum weed on beaches is a new phenomenon, and not one that can be explained easily. Climate change is suspected, influencing the oceanic circulation patterns, but there is no definitive explanation as yet.
That we only read of algae in the popular press when they become a nuisance is, however, a real problem. It creates the impression that algae are Bad Things that need to be controlled and kept at bay which, in turn, sets the agenda for environmental management. The reality is that algae are Good Things, without which life on earth (and soft ice cream) would not be possible (see “Every second breath….”, “Healthy streams are slippery streams” and other posts). However, preventing (or minimising the risk of ) Bad Things, does not necessarily mean that we have created an environment in which Good Things can thrive. Yet it is hard – very hard – to get that message across.