The vaquita is the world's smallest, and most endangered, cetacean. Only 7 to 10 were seen in the 2025 survey of the northern Gulf of California. Every individual alive matters. And every illegal gillnet set for totoaba fish kills one they cannot afford to lose.
The Most Endangered Marine Mammal on Earth
The vaquita marina, "little cow of the sea" in Spanish, is a small porpoise that exists nowhere else on Earth except a tiny patch of the northern Gulf of California, Mexico. It was only described as a species in 1958. In the 2025 survey, observers saw between 7 and 10 individuals.
The collapse has been staggering: about 567 vaquitas in 1997, 245 in 2008 and just 59 in 2015.
>> "Every death now is mathematically catastrophic. There is no margin."
Caught in the Wrong Net
Vaquitas do not die from hunting, nobody targets them. They die as bycatch: drowned in illegal gillnets set for the totoaba fish, whose swim bladder is smuggled to black markets in China. Fishermen can earn up to $8,500 per kilogram of swim bladder, which makes enforcement brutally difficult.
Mexican authorities have banned totoaba fishing and established a Zero Tolerance Zone. Sea Shepherd vessels patrol with the Mexican Navy, removing illegal nets. Every year, observers on Sea Shepherd ships and a network of underwater acoustic detectors try to confirm who, and how many, are still alive.
What Survives
The 2023 and 2025 surveys both confirmed that vaquitas are still reproducing: at least one calf was seen each time, and every animal looked healthy. A 2022 genome study published in Science found that the remaining population is not doomed by inbreeding: it is genetically healthy enough to recover if gillnet deaths stop.
The vaquita cannot be bred in captivity, a 2017 capture attempt ended in the death of one individual. The only path to survival is eliminating gillnets in the Zero Tolerance Zone, completely and permanently.
>> "As long as one vaquita is seen, and the habitat remains intact, recovery remains theoretically possible."
But every year without full gillnet removal is a year the species cannot afford.
_Sources: Sea Shepherd Conservation Society, "Results of the 2025 Vaquita Monitoring Effort", 28 October 2025. IUCN SSC Cetacean Specialist Group, "Joint visual and acoustic survey finds vaquitas surviving and reproducing mostly in and near the sanctuary", 2025. IUCN SSC Cetacean Specialist Group, "Vaquitas continue to surprise the world with their tenacity", 2023. IUCN SSC Cetacean Specialist Group, "Vaquitas not doomed to extinction by inbreeding depression", 6 May 2022 (on Robinson et al., Science). IUCN SSC Cetacean Specialist Group, "Vaquita" species page. NOAA Fisheries, "Vaquita" species page. Sea Shepherd Conservation Society, "Save the Vaquita Day 2026", 9 October 2026._