El loco

Harvest intensities of marine resources are causing remarkable changes in marine and intertidal communities. In general, fish stocks have decreased, leading to increasing number of endangered species, especially fish at higher trophic levels and those with high economic value.

Recently, ecologists have considered including humans as, not only modifiers, but also as top predators in the food web models. It is known that many top-down structured communities have cascading effects. When this occurs, persistent and high intensity predation can directly or indirectly affect the whole food web to lower trophic levels, causing community changes and potentially leading to extinctions. Therefore ecologists insist in the importance of protected or controlled harvest marine areas, where human activities are controlled or directly restricted.

Dr. Juan Carlos Castilla (Pontificia Universidad Católica de Chile and Margalef prize 2011) has studied the human disturbance effect over “el loco”, a valuable Chilean carnivorous gastropod (Concholepas concholepas). Dr. Castilla assessed loco communities in a non-disturbed rocky intertidal shore in a long term experiment set in the protected marine area at ECIM (5ha of human exclusion). Increased abundances of the gastropod were observed, and these trends have persisted until present day in the reserve. The results pointed towards the need of cooperation within fisheries management projects and ecologists.

The paper can be found at: link

Fence restricting the human access to the ECIM reserve

                                                          El loco, Concholepas concholepas