Why Vaquita Are Almost Extinct

Vaquita is an extremely rare species of porpoise found nowhere else except the northern Gulf of California. Their name means “little cow” in Spanish because these tiny, chubby porpoises are usually only about four feet long. Though they have few natural predators, the vaquita population has been dropping sharply in the past few decades. Currently, there are so few individuals left, that they are considered to be the most endangered cetacean species in the world.


The Rapidly Declining Vaquita Population

The number of existing vaquitas has always been small since they only live in one area in the entire world. However, until about the 1990s, vaquita had a respectably sized population in the Gulf of California region. By the 2000s, only about 300 vaquitas remained. Their population continued to drop sharply, and according to estimates in 2016, there are only about 60 remaining individuals nowadays. In just 20 years, the vaquita population has declined by over 92 percent. The Cetacean Specialist Group reports that vaquita will most likely be extinct in just a few years if drastic measures are not taken.

The Main Issues Harming Vaquita

The endangerment of animals in an incredibly complex subject, so many different factors can combine and threaten any species with extinction. As the number of vaquitas continues to drop, they face more and more issues due to a decreased breeding pool. Five primary reasons caused this population to drop so fast in recent years.

Gillnet Fishing

The primary cause of vaquita endangerment is the illegal gill net fishing that happens in their area. The Gulf of California is also home to the totoaba fish, another endangered species that is in high demand for traditional Chinese medications. Totoaba fishing is not legal, but a single totoaba swim bladder can sell for thousands of dollars on the black market. The totoaba are about the same size as vaquitas, so the illegal gillnets set out by fishers to catch the totoaba often end up finding vaquitas instead. Since the population needs to breathe oxygen to survive, many end up drowning after getting stuck in the gillnets. According to studies of the area, roughly 39 vaquitas are killed each year, and since there is so few vaquita, that amounts to about 17 percent of their species disappearance.

Difficulty Reproducing

Unlike dolphins or whales, the vaquita tends to be a solitary species that only interacts with each other during breeding. Unfortunately, the drastic decrease in their numbers means that they are having more and more trouble finding each other. There are so few individuals in their habitat that sexual reproduction is becoming rare.

The Colorado River Dam

The upper Colorado River used to flow into the Gulf of California, supplying freshwater to the region, and this created a unique blend of fresh and saltwater that allowed the vaquita to flourish. When the river was dammed, the flow of freshwater to the Gulf of California was drastically diminished. This ecological shift has harmed food supplies and proper nourishment, being a contributing factor in the population endangerment.

Environmental Pollutants

The water quality of the northern Gulf of California is declining in more ways than just reduced freshwater input. There has also been a recent increase in certain types of chlorinated pesticides within the waters of the vaquita habitat. Though these pesticides are not directly killing the species, any recent shift in the ecology of the area may be indirectly harming their population. An increase in pesticides may be harming developing fetuses or otherwise impacting vaquita growth and nourishment.

Declining Genomes

Though genome quality is not an immediate concern, it may ultimately become a massive issue. When an animal population is slim, the risk of inbreeding increases substantially. If animals with a similar genome mate, it is more likely for problematic recessive genes to start showing up in their offspring. Over time, this can result in weaker and less likely to survive in harsh conditions individuals. Biologists theorize that the vaquita breeding population needs to contain at least 50 individuals capable of reproduction to avoid all of the problems associated with inbreeding. This means that within just a year, there may not be enough vaquita left to produce a genetically fit population.

The Current State of  Vaquita Conservation

Because they are so endangered, many different organizations are working to help the vaquita. The president of Mexico put a ban on gillnet fishing last year which is supposed to last for at least 12 more months. Unfortunately, attempts to stop illegal fishing are hampered by the limited funds of the Mexican Navy. The Mexican government has also created a nature reserve that is intended to protect a portion of the vaquita’s natural habitat. In addition to these efforts implemented by the Mexican government, the North American Conservation Action Plan works to compensate fishermen who no longer work with gillnets.

You Can Make a Difference

Though the plight of the vaquita is indeed concerning, it may still be possible to save this incredible species. The biggest immediate threat is the fishing that continues to be a problem, but many fishermen cannot support their families without fisheries in the region. Therefore, donations to conservation plans that provide funding to stop illegal poaching and financial incentives to fishermen who stop using nets can provide a lot of help. The ban on gillnet fishing is almost over, so people who want to help can write letters to the Mexican Environmental Secretary to encourage the Mexican government to extend the ban until populations can effectively recover.