Shifting Baselines in the Gulf of California

Young Mexicans have a warped view of what is 'normal' in the Gulf of California. This was first shown in a marvelous 2005 study on Rapidly shifting environmental baselines among fishers of the Gulf of California where the authors interviewed 108 fishermen.

Compared to young fishers, old fishers named five times as many species and four times as many fishing sites as once being abundant/productive but now depleted. Old fishers caught up to 25 times as many Gulf grouper as young fishers on their best ever fishing day.

Their results were published in the Proceedings of the Royal Society and a great visual of shifting baselines also came out of their work.

Now, a new study (co-authored by two UBC Fisheries Centre scientists) Shifting environmental and cognitive baselines in the upper Gulf of California again confirms this. These authors collected local fishers' knowledge from 49 fishermen to quantify loss of anundance and diversity and found that ideas of marine abundance have shifted and so have actual fishing sites. The map below demonstrates the depletion of the west coast fisheries and the recent move east as fishermen search for better sites.

The authors of the 2008 study, published in Frontiers in Ecology & Environment, argue that a recognition of rapidly shifting baselines are essential for good decision-making in Mexico, where 65% of the population is under the age of 30. It's one matter to empirically demonstrate the shifting baselines syndrome but it will be another one to muster the political will to do something about it.