This project started after the PEMEX tank ship Lázaro Cárdenas II was
stranded in a reef area near Isla Espíritu Santo, B.C.S., destroying close
to a hectare of coral. After an initial stage of damage diagnosis, determining
urgent cleaning measures, and restoring it in collaboration with PROFEPA, we
finally reached the objective of this project, which is the monitoring phase of
the restored coral reef system.
The project pursues to determine the tendency toward recovery, or not,
of the impacted area and after having restored it in a period of 5 years. For
this purpose, we used two approaches: structural and functional.
The structural approach tries to determine if there is a recovery
tendency of the coral area. This is why seasonal monitoring is performed to estimate the
artificial reefs (modules) which were set up in the impacted area, evaluating
survival, growth of the corals cemented in the modules, and recruiting rate of
corals in the impacted area.
On the other hand, the functional approach focuses on the fauna and
flora associated to the restored area. For this purpose we characterize,
means of subaquatic census, composition, density, and seasonal variation
macrofauna associated to the impacted area specifically mollusks
clams), polychetes (polychete worms), crustaceans (crabs and shrimp)
echinoderma (starfish and sea urchin), and fish, as well as the richness
cover of algae.
To estimate the changes that occur in the restored area as objectively as possible, it is necessary to compare the results with control,
adjacent, close, and far areas. This is why the activities are performed in
several sites located in the bay of La Paz and in the bay of Loreto.
In general the results we have obtained up to date are positive in
structural terms because the modules have maintained their integrity; about 70%
of the cemented coral has survived and has grown in similar rates to other
regions. We have also detected a high recruiting rate of corals of the genera Pocillopora and Porites.
Functionally, we only have a differential use of the restored and witness areas by the different groups of organisms, because
dispersion speed of the organisms as well as habitat requirements are specific
and are temporarily modulated by the environmental dynamics of each period.