Vaquita facts for kids
Quick facts for kids Vaquita |
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| Size compared to an average human | |
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Phocoena
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| Species: |
sinus
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Vaquita (Phocoena sinus) is a rare type of porpoise. It lives only in the Gulf of California. The species is currently on the brink of extinction, and is listed as Critically Endangered by the IUCN Red List; the steep decline in abundance is primarily due to bycatch in gillnets from the illegal totoaba fishery.
Contents
Taxonomy
The vaquita was defined as a species by two zoologists, Kenneth S. Norris and William N. McFarland, in 1958 after studying the morphology of skull specimens found on the beach. It was not until nearly thirty years later, in 1985, that fresh specimens allowed scientists to describe their external appearance fully.
The genus Phocoena comprises four species of porpoise, most of which inhabit coastal waters (the spectacled porpoise is more oceanic). The vaquita is most closely related to Burmeister's porpoise (Phocoena spinipinnis) and less so to the spectacled porpoise (Phocoena dioptrica), two species limited to the Southern Hemisphere. Their ancestors are thought to have moved north across the equator more than 2.5 million years ago during a period of cooling in the Pleistocene. Genome sequencing from an individual captured in 2017 indicates that the ancestral vaquitas had already gone through a major population bottleneck in the past, which may explain why the few remaining individuals are still healthy despite the very low population size.
"Vaquita" is Spanish for "little cow".
Description
The smallest living species of cetacean, the vaquita can be easily distinguished from any other species in its range. It has a small body with an unusually tall, triangular dorsal fin, a rounded head, and no distinguished beak. The coloration is mostly grey with a darker back and a white ventral field. Prominent black patches surround its lips and eyes. Sexual dimorphism is apparent in body size, with mature females being longer than males and having larger heads and wider flippers. Females reach a maximum size of about 150 cm (4.9 ft), while males reach about 140 cm (4.6 ft). Dorsal fin height is greater in males than in females.
Distribution and habitat
Vaquita habitat is restricted to a small portion of the upper Gulf of California (also called the Sea of Cortez), making this the smallest range of any marine mammal species. They live in shallow, turbid waters of less than 150 m (490 ft) depth.
Diet
Vaquitas are generalists, foraging on a variety of demersal fish species, crustaceans, and squids, though benthic fish such as grunts and croakers make up most of the diet.
Social behavior
Vaquitas are generally seen alone or in pairs, often with a calf, but have been observed in small groups of up to 10 individuals.
Little is known about the life history of this species. Life expectancy is estimated at about 20 years and age of sexual maturity is somewhere between 3 and 6 years of age. While an initial analysis of stranded vaquitas estimated a two-year calving interval, recent sightings data suggest that vaquitas can reproduce annually. It is thought that vaquitas have a polygynous mating system in which males compete for females.
Population status
Because the vaquita was only fully described in the late 1980s, historical abundance is unknown. Since 1983, all confirmed specimens, records, and sightings of P. sinus were evaluated. There were 45 records of P. sinus that were collected by skeletal remains, photographs, and sightings in 1983. The first comprehensive vaquita survey throughout their range took place in 1997 and estimated a population of 567 individuals. By 2007 abundance was estimated to have dropped to 150. Population abundance as of 2018 was estimated at less than 19 individuals. Given the continued rate of bycatch and low reproductive output from a small population, it is estimated that there are fewer than 10 vaquitas alive as of February 2022. In 2023, it is still estimated that there are as few as 10 in the wild. A 2024 survey observed a minimum of 6 to 8 individuals (with a maximum of 9 to 11), the lowest ever count, but this number may just be a result of the small survey area instead of an actual population decline, as vaquitas freely move in and out of the survey region.
Threats
Fisheries bycatch
The drastic decline in vaquita abundance is the result of fisheries bycatch in commercial and illegal gillnets, including fisheries targeting the now-endangered Totoaba, shrimp, and other available fish species. Despite government regulations, including a partial gillnet ban in 2015 and establishment of a permanent gillnet exclusion zone in 2017, illegal fishing remains prevalent in vaquita habitat, and as a result the population has continued to decline.
Other threats
Given their proximity to the coast, vaquitas are exposed to habitat alteration and pollution from runoff. Bycatch is the single biggest threat to the survival of the few remaining vaquita. Exposure to toxic compounds has also had a deleterious effect on vaquitas.
Predation on vaquita by sharks has also been reported from fishermen, who have seen whole or parts of individuals in the stomachs of caught sharks however no quantitative analysis is readily available. However, the biggest threat still towards vaquita are fisheries. Northern fishing fleets have had an indirect positive impact mainly on marine mammals, because fishing on predators like sharks reduces its predatory negative impact on those groups. Although, the predation of sharks towards vaquita do result in a decline in population and is seen as an alternate threat, northern fishing fleets also negatively impact this small marine mammal because the negative influence of incidental catch is greater than the positive influence of predation reduction by shark fisheries.
Conservation
Conservation status
The vaquita is listed as critically endangered on the IUCN Red List, which is only one level above being completely extinct in the wild. It is considered the most endangered marine mammal in the world. The vaquita has been listed as critically endangered by the IUCN Red List of Threatened Species since 1996. The vaquita is at risk of extinction due to its small population size. It was approximated at one point that there were 150 individuals.
In 2019, the UNESCO World Heritage Site where the last vaquita are located was classified as a World Heritage Site in Danger.
The vaquita is also protected under the Endangered Species Act of 1973, the Mexican Official Standard NOM-059 (Norma Oficial Mexicana), and Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
For a small population such as the vaquita to recover after a severe decline in population size is very difficult. This conservation status is strongly influenced in part of the species reproductive biology. The large amount of unknown surrounding the key reproductive parameters of the vaquita makes understanding its potential for recovery even harder.
Conservation efforts
The vaquita is found only in the upper Gulf of California, Mexico area. The vaquita is at risk of extinction due to its small population size. It was approximated at one point that there were 150 individuals left with a 10% annual decline within their population. Anthropogenic effects of a rise in commercial fishing such as accidental by-catch, illegal fishing, and entanglement have been linked to the cause of their decline. Shrimp fishing and gillnets create entanglement issues for the vaquita. Aspects of illegal fishing include open access fisheries and absent fisheries management have correlated towards poaching of the main prey source of the vaquita. The swim bladders of the Totoaba macdonaldi are being sold on the black market by cartels for profit.
The Mexican government, international committees, scientists, and conservation groups have recommended and implemented plans to help reduce the rate of bycatch, enforce gillnet bans, and promote population recovery.
Protection efforts throughout Mexico have taken place in order to preserve the population. In 2017, the Government of Mexico established it as a felony to remove an endangered species. Alongside this, the Government of Mexico also made a public agreement to prohibit gillnet use. Efforts are proactive in incentive applications to fisheries in a system of trade-offs that benefit fishermen and the vaquita.
Mexico launched a program in 2008 called PACE-VAQUITA in an effort to enforce the gillnet ban in the Biosphere Reserve, allow fishermen to swap their gillnets for vaquita-safe fishing gear, and provide economic support to fishermen for surrendering fishing permits and pursuing alternative livelihoods. Despite the progress made with legal fishermen, hundreds of poachers continued to fish in the exclusion zone. Poaching continues as the swim bladders of totoaba can sell for anywhere from $20,000 to upwards of $80,000. A black market for totoaba swim bladders has developed fairly recently in China (including Hong Kong). In 2017, poachers received up to US$20,000 for a kilogram of totoaba swim bladders, with some making as much as $116,000 in one day.
The swim bladders of the Totoaba macdonaldi are being sold on the black market by cartel for profit. With continued illegal totoaba fishing, which is largely motivated by sales to the Chinese market where it is used in traditional medicine, and uncontrolled bycatch of vaquitas, the International Committee for the Recovery of the Vaquita (CIRVA) recommended that some vaquitas be removed from the high-density fishing area and be relocated to protected sea pens. This effort, called VaquitaCPR, captured two vaquitas in 2017; one was later released and the other died shortly after capture after both suffered from shock.
Local and international conservation groups, including Museo de Ballena and Sea Shepherd Conservation Society, are working with the Mexican Navy to detect fishing in the Refuge Area and remove illegal gillnets. In March 2020, the U.S. National Marine Fisheries Service (NMFS) announced a ban on imported Mexican shrimp and other seafood caught in vaquita habitat in the northern Gulf of California.
In response to the dire circumstances facing the vaquita as by-catch of the illegal totoaba trade, in 2017 Earth League International (ELI) commenced an investigation and intelligence gathering operation called Operation Fake Gold, during which the entire illicit totoaba maw (swim bladder) international supply chain, from Mexico to China, has been mapped and researched. Thanks to the confidential data that ELI shared with the Mexican authorities, in November 2020, a series of important arrests were made in Mexico.
To date, efforts have been unsuccessful in solving the complex socioeconomic and environmental issues that affect vaquita conservation and the greater Gulf of California ecosystem. Necessary action includes habitat protection, resource management, education, fisheries enforcement, alternative livelihoods for fishermen, and raising awareness of the vaquita and associated issues.
Jaramillo-Legorreta, et al. stated in 2007 that captive breeding programs were not a viable option for saving the species from extinction.
The Secretariat of Environment and Natural Resources (SEMARNAT) announced on February 27, 2021, that it may reduce the protected area for the vaquita in the Sea of Cortés as there are only ten of the porpoises left and it may never recuperate its historical range.
Beginning in July 2022, the Mexican government placed 193 concrete blocks in the Gulf of California no-tolerance zone, intended to allow the detection of nets by acoustic sonar and prevent further entrapment of vaquitas.
Creating protected areas is always an option for conservationists, but because the vaquita's range is so small, there would be no use in trying to establish habitat corridors. One option for conservationists could be trying to create buffer zones near the coast in which pesticides harmful to vaquitas are restricted or even unavailable in order to enhance the protection value of the vaquita's range.
In May 2023, a wildlife survey expedition discovered that the population had stabilized since it had last been recorded in 2021.
In October 2024, Colossal Biosciences announced their non-profit foundation dedicated to conservation of extant species, with one of their first projects being the vaquita. Colossal plans to biobank genetic material to revive the species if it were to become extinct, and to use acoustic sensors and drones to monitor vaquitas in collaboration with CONANP.
See also
In Spanish: Vaquita marina para niños
