Conservation of Nature
Sand coral reefs
The colonies of the honeycomb worm (Sabellaria alveolata), a polychaete worm, can develop into authentic reefs covering vast parts of the lower intertidal zone, providing innumerous micro-habitats for a very rich associated fauna. The reefs play a fundamental role in the structure and dynamics of an intertidal community. The morphology of the rocky substrate is altered vertically by raising the substrate level in relation to the sea level. The ecological conditions of each site are modified and the biomass per unit of surface is increased, contributing to species richness of the intertidal zone.
But human activities such as baitdigging by sports fishermen, searching for crabs and octopus, curiosity and footstepping, provoke erosion that causes a big interference in the natural life cicle of the reef and can result in complete destruction.
Information leaflets about the conservation and protection of sea turtles and local sand coral reefs are distributed among ELA´s visitors.
At ELA, the Loggerhead sea turtle (Caretta caretta) was received with some regularity until 2008, but also rarities such as Kemp’s Ridley (Lepidochelys kempii). Since then, there have been no more registrations. Dead Leatherback turtles (Dermochelys coriacea) were still recorded with some frequency until 2017.
For rehabilitation, marine turtles were maintained inside the building in controlled conditions for several weeks. Before release, they were tagged with a microchip on the backside of the neck and then reintegrated into the ocean beyond 40 nautical miles, with the help of the Portuguese Coast Guard.
A didactic leaflet is distributed among ELA´s visitors, informing about the species and its threats, with instructions on what to do and how to do it if a marine turtle is found alive on the beach or caught in a net.
The project includes systematic marking-recapture experiments. The lobsters, caught by experimental or commercial fishing, are recovered in captivity during several weeks between May and October. They are then marked with an ultraviolet light-sensitive coloured ink in the abdominal ventral part, and released into the sea over rocky substrate at depths between 8 and 10 m.
When a female with eggs is captured, culture experiments are carried out for the purpose of restocking the sea of Aguda. The larvae are fed first with live zooplankton (bay brine shrimp, genus Artemia) and then, after being separated to avoid cannibalism, with granules of gradually larger size and, in a more advanced state, with blue mussel flesh.
Juvenile lobsters from culture experiments are introduced into the sea with the help of a diver.
ELA often receives sea birds found on the beach that are exhausted, injured or contaminated by hydrocarbon products (figs. 456, 457). These animals are given “first aid”, then are fed and, after a short period of rest, sent to the Veterinary Clinic of the Biological Park of Vila Nova de Gaia, in Avintes.