The biggest threat to the vaquita is presented by fishermen that use gillnets. The area inhabited by this endangered porpoise is surrounded by three fishing villages.
The main method of fishing in the area is with small skiffs (pangas) that lay gillnets with bouys for several hours at a time. These indiscriminately destructive gillnets are normally made with transparent or green nylon. Combined with the murky quality of the water in the upper Gulf of California, these nets are nearly invisible to the vaquita. As they swim within the marine refuge, the porpoises often become entangled in the nets causing them to suffocate.
In the past few years the totoaba fishery resurged in the region, fueling the decline of the vaquita population to the never-before-seen rate of an astounding 18.5% each year.
The totoaba bass is another endangered marine species native to the upper Gulf of California. The totoaba’s story, like that of the vaquita, is a sad one and is tightly intertwined with the story of San Felipe, the fishing town nearest to the vaquita’s territory. San Felipe was essentially founded because of the totoaba fishery. The totoaba were once an abundant and large fish, weighing up to 300 pounds and growing to more than six feet long. Now, with so few left, it is very rare to spot a totoaba that weighs even 70 pounds. They were hunted to near extinction in the 1960s. Even then, the fishermen were after the totoaba for their swim bladder. The swim bladder is exported from Mexico and sold on the black market in China where it is used for a soup believed to have medicinal properties.
Since 1975, the totoaba has been protected in Mexico when it was listed as an endangered species due to the mad hunt for its swim bladder. In the past few years, the totoaba population made a small comeback; unfortunately, this recovery motivated illegal fisherman and the Mexican criminal cartels to target the endangered fish once more to export the fish’s swim bladder for sale on the black market in China. The resurgence of this market has been devastating not only for the totoaba, but for the dwindling vaquita population. The totoaba fishery resurgence has accelerated the decline of the vaquita from 7.5% annually to 18.5% annually. The gillnets set for totoabas are of a mesh greater than six inches, making their use illegal. The use of these gillnets also makes it more likely for the vaquita to become entangled and drown. The fate of this very shy and elusive porpoise is inextricably tied to the fate of the totoaba.