Written By: Joshika P.
Cover Design By: Gowri C.
What is a Vaquita?
The vaquita (Phocoena sinus) is the smallest cetacean on the planet. In Spanish, its name means "little cow." Its most distinguishing characteristic is a black ring around the eyes, as well as a relatively large dorsal fin. The vaquita is unique among porpoises, being that it is the only member of the family that lives in warm seas, and the size of its dorsal fin is thought to be an adaptation to this, enabling excess body heat to escape. Vaquita can only be found in the northern Gulf of California, in Mexico's Sea of Cortez.
Vaquita, like many other porpoise species, are wary and evasive, avoiding sea vessels when approached. They can generally be found in shallow waters up to 50 meters deep. And, like their closest relative, the harbour porpoise, they tend to favor turbid, nutrient-rich coastal waters that attract their preferred prey, which includes tiny fish, cephalopods, and crustaceans.
Accidental entanglement is the single most danger to the vaquita's survival. As by-catch, the little mammal is frequently trapped in gill-nets. The entangled creatures drown within minutes because they are unable to surface for air. This vulnerability is increased by illegal fishing for another endangered species found in the vaquita ecosystem, the totoaba, a big species of fish sought after for its swim bladder, spurred by demand from China, where it is considered a delicacy with medical benefits.
An Overview of Gillnets
A gillnet is a type of net that captures fish by their gills. Like other entanglement nets, they are used in offshore and inshore waters, and in rivers and estuaries. It works like this: the netting's thread is incredibly thin, so the fish either don't notice the net or the net is set to capture the fish. The net's meshes hang completely open. When the fish swims up to the net, it sticks its head right into one of the meshes. As the fish tries to escape out of the mesh its gills get caught in the net. Gillnets have the highest bycatch rate of any other type of fishing net, but their use is reducing. In some circumstances, gillnets can be sustainable; for example, salmon gather at choke points that can be blocked off without impacting other species.
Mexico’s Ban on Gillnets
The Mexican government declared a two-year ban on gill-net fishing in vaquita habitat in April 2015, which was enforced by the Mexican navy. Conservation groups applauded the idea, but cautioned that it did not go far enough until the ban was made permanent. To aid in the fight against poachers, a permanent ban was finally announced in July 2016, along with a restriction on night fishing. However, illicit fishing is to blame for the vaquita's severe fall, which is unlikely to be reversed soon.
How They Are Affecting the Environment
Gillnetting has posed a significant threat to all sea turtle and marine mammal species. The openings of the gill nets are meant to capture fish as they swim through and become stuck behind their gills, and while the net can be selective in terms of fish, larger marine species suffer significantly since they are essentially swimming into a death trap. Entanglement may prevent regular feeding, limit growth, or induce illness after many months. Marine mammals captured in set gillnets can drown, but those caught in drift gillnets can drag gear for miles as they migrate and forage, resulting in extreme weariness.The use of mile-long drift gillnets to collect swordfish off the coast of California entangles, injures, and kills big ocean animals such as whales, dolphins, seals, sea turtles, numerous shark species, and many other ecologically and commercially important fish.
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