Part of the coastline in Portimão has been transformed by a thick carpet of brown algae, rugulopteryx okamurae, with tonnes of the invasive species washing ashore and covering stretches of sand.
At Barranco das Canas beach, better known as Praia do Alemão, the accumulation has become so extensive that bathing has been prohibited until the algae can be cleared. Beach facilities have also been closed, while access to the sand is being restricted.
The mass arrival of the exotic algae, commonly termed Japanese algae, is not a new sight along the coast of the Algarve. However, the phenomenon has intensified in recent years, with the invasive brown species periodically smothering beaches in a dense blanket, disrupting seaside activities during the summer months.
Portimão City Council has attributed the latest influx to what it calls a “southeasterly sea”. When winds blow from the southeast, bringing stronger waves and currents, they alter the dynamics of the coastline, dislodging mats of Japanese algae from the seabed and carrying them towards the shore.
The western Algarve is particularly affected.
Although the algae is not toxic, large accumulations can create a series of unwelcome consequences. As the seaweed decomposes in the heat of the sun, it gives off a strong and unpleasant smell, attracting pests and insects.
There is, however, no deterioration in bathing-water quality as a result of the algae, according to the authorities.
The sheer volume of algae at Praia do Alemão has led Portimão’s authorities, working with the National Maritime Authority, to close the bathing area. The concession area has also been shut, and access to the beach restricted while clearance work gets under way.
Machines operated by Portimão’s municipal water and waste company have been brought in to remove the algae. The operation is expected to continue until 7pm on Friday, with crews working to clear the thick layer that has accumulated along the shoreline.
Source: JN
Photo credit: CM Portimão
