Why is the Vaquita Almost Extinct?

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If you’re wondering what a vaquita is, you should first check out our previous blog article, which answers this question in great detail.

I’ll tell you here, that the vaquita is species of porpoise (a marine mammal related to whales and dolphins) found only in the Northern Gulf of California in Mexico – it is the most endangered marine mammal on the planet, and has likely been in decline since the 1940s.  By the time my friend and collaborator Sean Bogle and I got involved with the issue in 2015 the situation was critical.  At that time it was estimated that there were just under 100 individuals remaining, and Sean and I spent a lot of time discussing their situation.  We knew that there was a good chance that the species would go extinct, but we didn’t yet fully understand what was driving the vaquita’s dramatic decline.

To unpack the causal factors behind the decline of the vaquita, we needed to spend some time in the Northern Gulf of California region in Northwestern Mexico (locally referred to as the upper gulf) where the vaquita lives.  We talked to scientists, politicians, fisherman, law enforcement officers and numerous local community members.  With each trip that we took to the area, we uncovered additional layers to the issue and learned more about why the vaquita population was declining so rapidly.

We learned that the story behind the vaquita’s dramatic decline begins with the settlement of the upper gulf region.  Fisherman established the first modern small communities in the Northern Gulf of California in the 1920s in response to the demand for a large fish called the totoaba.  There was a market for the swim bladder of this fish in China (it is used as a postpartum aid in traditional Chinese medicine), and this market led to the establishment of a commercial fishery for the species.  Initially this fishing activity probably did little to no harm to the vaquita population, but in the 1940s fisherman began using gillnets to catch totoaba.  A gillnet is a large net that is left to drift with the ocean currents while it passively captures fish and other marine life.  While this innovation dramatically increased the yield for the totoaba fishery, it also dramatically increased the amount of bycatch that fisherman were pulling up.

Bycatch is a global problem – gillnets are an extremely common method of fishing, and wherever gillnets are being used, there are lots of non-target species being killed in those nets.  Marine mammals are particularly susceptible because once they get entangled in these nets they are unable to surface and soon drown.  This is what began to happen to the vaquita in the 1940s with the advent of gillnetting in the upper gulf, and there was almost certainly an immediate impact on the population.

Over the next three decades the commercial totoaba fishery exploded – more fisherman came to the upper gulf to participate in this lucrative activity, and more and more vaquitas were drowned in gillnets.  There were no population assessments done for the vaquita during this time – it had only been known to science since the early 1950s – so we can only guess at the scale of the negative impact that this intensive period of totoaba gillnet use had on the population. 

By the 1970s the totoaba was suffering from three decades of regulation-free intensive harvesting – the population was on the brink of collapse.  Recognizing this for the first time, both the Mexican government and the international community listed the species as critically endangered and shut down the fishery.  The totoaba was actually one of the very first species listed by the International Union for the Conservation of Nature (IUCN) as endangered – this took place in 1975.

Although some small level of illegal totoaba harvest almost certainly continued, the legal market for totoaba swim bladders had been shut down, and this created an opportunity for both the totoaba and the vaquita populations to recover.  Unfortunately, the totoaba fishery was soon replaced by the very lucrative market for blue shrimp in the United States.  Gillnets were seen as the most efficient method for catching blue shrimp as well, so the practice of gillnetting did not end.  In fact – by the 1970s the vast majority of all local fisheries relied on gillnets.  Not all of these gillnets were the same however – the gillnets used for shrimp have very small openings in the mesh, while the totoaba gillnets have large openings to catch fish like the totoaba that can grow up to 8 feet in length.

The gillnets designed to catch totoaba were, and are, the most deadly for the vaquita.  This is because the vaquita is close in size to the totoaba, so they easily become entangled in the same nets.  Shrimp gillnets can still be deadly for a vaquita, but they are less likely to cause entanglement because the openings in the mesh net are much smaller.  Nevertheless, with gillnets still in regular use, the vaquita population almost certainly continued to decline after the totoaba fishery was shut down.  There was still no population assessment for the vaquita, so we can only guess at what the species’ rate of decline was during this period, or if the closure of the legal totoaba fishery had any impact on this decline.

By the 1990s there was a group of marine mammal biologists that were starting to take a comprehensive look at the vaquita population.  The first population survey was conducted in 1997, and resulted in an population estimate of just under 600 individuals.  These same scientists also began to conduct genetic research on the species, and this research led them to estimate that the historic population was made up of approximately 5,000 individuals.  So five decades of gillnetting had caused a huge decline in the vaquita’s population.

In 2008 another population survey was conducted, and it was determined that approximately 245 vaquitas remained – meaning that more than half the population had been lost since 1997.  This prompted a big push to find solutions to the gillnetting problem – the Mexican government offered buyouts to local fisherman, but few took advantage of the program.  The government also began testing alternative fishing gear that wouldn’t harm the vaquita, but only a select few opted to participate in the program.  The vast majority of fisherman just continued to use their gillnets.

When these incentive-based programs failed to have an impact on the vaquita’s decline, an outright ban on the use of all gillnets throughout the entire region began to be considered.  By 2015 there was a lot of international pressure on the Mexican government to ban all gillnets, and President Peña-Nieto finally imposed the ban.  Unfortunately, by 2015 there was a resurgence of the illegal totoaba fishery already well underway.

The totoaba fishery had been illegal since 1975, but by 2010 the demand for their swim bladders had taken off, and an illegal supply chain was being established.  By the time all gillnets were banned throughout the upper gulf, there was already a thriving illegal totoaba fishery with a robust supply chain that connected Mexican drug cartels with the Chinese mafia to facilitate the transport of this bizarre product halfway around the world.

While the gillnet ban was successful in virtually eliminating the gillnets being set for shrimp and other small fish, the swim bladders of the totoaba were worth so much money that fisherman were willing to take the risk of getting caught.  In fact, we were told by several local fisherman that the gillnet ban actually increased participation in the illegal totoaba fishery, because people needed to find alternate work after the closure of the shrimp fishery.

This idea that the gillnet ban may have inadvertently increased participation in the illegal totoaba fishery was corroborated by a marked increase in the vaquita’s rate of decline the following year.  In 2015 there were an estimated 60 vaquitas remaining in the upper gulf – but by 2016 that number had dropped to 30 – a startling 50% rate of decline.

2015 was the year when we began shooting for our documentary project about the vaquita, and we watched as the influence of organized crime became more and more prominent in San Felipe, and the other communities of the upper gulf.  By the end of 2016 it was clear to us that the situation was getting worse, not better.  Illegal totoaba fisherman were becoming more brazen, and it was quite clear to us that many of the Navy officers tasked with enforcing the gillnet ban were being paid to look the other way.  The officers who weren’t being paid off were too scared of the cartels to take any kind of enforcement action.

With the clear failure of the gillnet ban to have any kind of positive impact on the vaquita population, one final attempt would be made to prevent the extinction of the vaquita.  In the fall of 2017 over 60 marine mammal experts from all across the globe converged on San Felipe, Mexico to launch a captive breeding program for the vaquita.  This was billed as the last hope for the species, and it came at a time when there were likely about 15 individuals remaining.

No one had ever attempted to live capture a vaquita before, and it was known from the beginning of this operation that there were a lot of risks involved.  Not all cetacean species adapt well to a captive environment, and everyone involved was worried that even if a vaquita was successfully captured, it would refuse to accept captivity.

Over the course of about two months, two vaquitas were successfully captured.  The first was a juvenile female, who was extremely stressed out right from the first moment of capture.  After holding this individual for several hours, she was released back into the upper gulf, for fear that she would die from the stress.  Although this was certainly not a good sign for the prospect of a successful integration into captivity, scientists were hopeful that an adult vaquita would fare better.

Then, with less than a week left until the capture effort was set to end, an adult female vaquita was captured.  Initially she seemed to be doing quite well at adapting to the captive environment, but after several hours things took a turn for the worse.  The animal stopped breathing and an emergency release occurred too late to prevent the vaquita’s death.  With the death of this individual, the decision was made to shut down the vaquita capture program.

The death of that vaquita was crushing, both for the scientists involved, and for Sean and myself.  In many ways that one individual animal represented hope for the future of the species, and its death brought the reality of extinction to the forefront of everyone’s mind. 

Although those who are directly involved in the vaquita issue are reluctant to say that they’ve given up hope, the reality is that extinction is almost certainly inevitable.  This is not to say that important conservation work going on in the region should end – these efforts benefit numerous other species in the Sea of Cortez.  The Sea Shepherd Conservation Society has been collaborating with a group of local fisherman for the past two years to remove large numbers of illegal and/or abandoned gillnets from the water.  The scale of this effort is enormous – close to 1,000 nets have been removed over the past five years – not an insignificant number.  Were it not for this effort, it’s possible that the vaquita would already be gone.  There is also a slim possibility that the new president of Mexico, who is set to take office in the coming months, could purge the government ranks of corrupt officials and work to address the issues surrounding organized crime in a comprehensive way.  But could this be done within the ever narrowing window of time that we have before the vaquita disappears forever?  Sadly, it’s a virtually impossible task.

So although a small handful of individuals remain in the wild at this time, the vaquita will almost certainly be gone within the next year or two, and the Sea of Cortez will never be the same without them.