While its historical range stretched as far north as Humboldt Bay, California, today it is a rare sight in US waters following the collapse of the fishery in the early 1900s. Dr. Ramirez was particularly interested in learning more about the population south of the border, where very little investigation had been conducted despite a continued commercial fishery on a much smaller scale. This fish is listed as critically endangered by the International Union for the Conservation of Nature (IUCN), landing it on the undesirable ‘red list’. However the IUCN assessment looked at data largely taken from only the northern half of the GSB’s distribution.

In order to gather more data on where remaining fish were, as well as their sizes and ages to build a better idea of current population trends, Dr. Ramirez forged a collaboration with fishing cooperatives on the Baja Peninsula. Fishers from all over shared where the fish were seen and harvested, and even saved fish heads to extract the otolith, a calcified organ in the ear that exhibits growth rings that allow one to discern the age of an individual. His research shows that GSB numbers are higher than earlier estimates had shown, likely due to the paucity of analyses  including study from Mexico. By working with fishers he was able to expand on earlier studies and examine population trends with far higher resolution.

These collaborations proved to be invaluable assets to the research while also providing useful information to cooperatives eager to know more about the state of any fishery. Many fishers commented that mero gigante was hardly targeted anymore because numbers had indeed been greatly reduced. Nonetheless, this study shines a light on the importance of both international and interdisciplinary collaboration for marine conservation and resource management.

Borderless Blue emphasizes the historical context that has impacted giant sea bass populations and influenced their IUCN listing. Today this fish is protected in the US with all fishing strictly prohibited in the name of conservation, while south of the border an active fishery persists. The lack of international collaboration may be stalling any real population recovery and limiting our potential to understand more about these magnificent animals.

The giant sea bass remains on the IUCN’s red list as a critically endangered species, though Dr. Ramirez’s research shows that there may be more to the story here. If the population is larger than previously thought in its southern range, the potential for collaborative, binational conservation to encourage population recovery is higher than ever, and all the more worth pursuing. For more information visit merogigante.org.