Rare Baja Porpoise Likely Extinct by 2018, Yet Illegal Fishing Continues in Refuge
An international recovery team reported in August that the vaquita, an incredibly rare marine mammal found only in the Sea of Cortez and the Colorado River Delta, will likely be extinct by 2018 unless drastic measures are taken to protect it. Despite that dire warning, satellite photos taken earlier this month show that illegal gill-net fishing is rampant in an area of the Sea of Cortez set aside for vaquita protection.
According to the International Union for the Conservation of Nature's Cetacean Specialist Group, satellite photos taken December 5 show 90 gillnet fishing boats inside the Vaquita Reserve off the Baja California town of San Felipe, in an area legally closed to gillnet fishing.
An estimated 97 vaquita still survive, down from around 200 in 2012. The diminutive porpoises are especially susceptible to drowning when entangled in gillnets. An increase in activity in the illegal fishery for totoaba, an endangered fish whose swim bladder is thought by wealthy Chinese diners to offer health benefits, may be driving the recent steep decline in vaquita numbers.
A close relative of the harbor porpoise, the vaquita, Phocoena sinus, is generally considered the most endangered cetacean in the world. The vaquita inherited that dubious honor when the Yangtze River dolphin or baiji was declared extinct in 2006. Like the baiji, the vaquita has a very small geographic range -- just the north end of the Sea of Cortez -- reproduces slowly, with an average of ten years between generations, and is often injured by fishing nets. The vaquita's small size -- smaller than an average adult male human -- and preference for shallow water makes it especially vulnerable to gillnet fishers in the Sea of Cortez.
In August, the Comité Internacional para la Recuperación de la Vaquita -- the International Committee for Vaquita Recovery, a.k.a. CIRVA -- released a report based on recent acoustic surveys for the diminutive cetacean. CIRVA reported that the vaquita population has been dropping by about 18.5 percent a year, and estimated that only 25 of the remaining vaquitas are females of reproductive age.
The Committee urged the Mexican government to enact a ban on all gillnet fishing in the northern Sea of Cortez effective in September, warning that the vaquita would otherise be extinct as soon as 2018:
In the past three years, half of the vaquita population has been killed in fishing nets, many of them set illegally to capture an endangered fish. Fewer than 100 vaquitas remain and the species will soon be extinct unless drastic steps are taken immediately.
The groups also recommended stepped up enforcement of the existing gillnet ban.
