Can the Vaquita Porpoise be saved from extinction?

Understanding the smallest Cetacean’s fight for survival

The vaquita porpoise in Mexico´s Gulf of California. Photo by PROFEPA 

The vaquita porpoise (Phocoena sinus) is the smallest cetacean alive and one of the most endangered marine mammals. Found exclusively in Mexico’s Gulf of California, its population has plummeted from 600 individuals in 1997 to fewer than 10 by 2021 [1]. This critical decline is driven primarily by illegal fishing and bycatch in poachers’ gillnets. Despite this, new genetic research offers a glimmer of hope for the species’ survival.

Is the Vaquita Porpoise extinct?

The vaquita is not extinct, but it is critically endangered. Fewer than 10 individuals remain in the wild, making its survival precarious. Conservation efforts and enforcement of anti-poaching measures are essential to prevent its extinction.

Why is the Vaquita in danger?

The vaquita’s decline is tied to human activity:

1. Illegal Fishing and Bycatch: The vaquita often becomes entangled in gillnets intended for totoaba fish, whose swim bladders are highly valued in traditional Chinese medicine [6].

2. Weak Enforcement: Despite bans on gillnets in the vaquita’s habitat, poor enforcement of fishing regulations continues to put the species at risk [8].

3. Small Population Risks: With so few individuals left, finding mates becomes difficult, increasing the likelihood of inbreeding [2].

Undated photo of a dead vaquita trapped in a gillnet used to catch totoaba. Mexico´s Gulf of California. Photo by BBC. 

Can the Vaquita be saved?

Recent research provides a reason for optimism. A study led by UCLA, NOAA Fisheries, and other institutions found that the vaquita’s genetic makeup offers resilience against inbreeding depression. This resilience stems from their historical rarity, which has minimized the accumulation of harmful mutations over generations [3].

Key findings from the genetic study

• Researchers sequenced DNA from 20 vaquita tissue samples collected between 1985 and 2017.

• Computational simulations predicted that the species could survive if bycatch is eliminated.

• The vaquita’s historical population size helped reduce harmful genetic mutations, allowing it to maintain relatively good health despite low diversity [3].

Lessons from other species

The vaquita is not alone in demonstrating that small populations can survive and even thrive under the right conditions. Examples include:

• Northern Elephant Seal: Once reduced to 20-30 individuals, this species now numbers around 100,000 [3].

• Mountain Gorilla and Iberian Lynx: Both species rebounded thanks to intensive conservation efforts [4].

• Channel Island Foxes: Their survival highlights the importance of managing harmful mutations [5].

“Relative to other species, the vaquita has a higher chance of rebounding from an extreme population crash without suffering severe genetic consequences from inbreeding”

— Dr Jacqueline Robinson of the University of California, San Francisco.

Fisheries officials and a Mexican marine confiscating an illegal net in Baja California Photo by G Arias/Getty. 

What’s next for the Vaquita?

The future of the vaquita hinges on human actions. Key steps include:

1. Enforcing Gillnet Bans: Stronger enforcement of existing laws against gillnets in vaquita habitats is crucial [8].

2. Community Engagement: Collaborating with local fishing communities can help promote sustainable practices and reduce resistance to conservation measures.

3. International Cooperation: Addressing the global demand for totoaba swim bladders requires tighter international regulations and awareness campaigns [6,7].

4. Innovative Monitoring: Technologies like acoustic monitoring and drones can improve the detection and protection of remaining vaquitas [9].

A symbol of hope

The vaquita is a unique symbol of the Gulf of California’s biodiversity and a reminder of the delicate balance required to preserve endangered species. While their population is alarmingly small, recent genetic studies suggest they have the resilience to recover if bycatch and illegal fishing are eliminated. Ultimately, their survival depends not on their genetics but on humanity’s commitment to conservation.

References

1. Jaramillo-Legorreta AM, Cardenas-Hinojosa G, Nieto-Garcia E, et al. Decline towards extinction of Mexico’s vaquita porpoise (Phocoena sinus). Royal Society Open Science. 2019;6(7):190598.

2. Charlesworth D, Willis JH. The genetics of inbreeding depression. Nature Reviews Genetics. 2009;10(11):783–96.

3. Robinson JA, Kyriazis CC, Nigenda-Morales SF, et al. The critically endangered vaquita is not doomed to extinction by inbreeding depression. Science. 2022;376(6593):635–639.

4. Wiedenfeld DA, Alberts AC, Angulo A, et al. Conservation resource allocation and small population resiliency. Conservation Biology. 2021;35(5):1388–1395.

5. Robinson JA, Brown C, Kim BY, et al. Purging of strongly deleterious mutations explains persistence in island foxes. Current Biology. 2018;28(21):3487–3494.

6. Carrington D. Chinese appetite for totoaba fish bladder kills off rare porpoise. The Guardian. 2017. Available at: https://www.theguardian.com/environment/2017/may/16/chinese-appetite-totoaba-fishbladder-threatens-rare-vaquita.

7. Martínez IA, Alonso AI. Mexican organized crime and the illegal trade in totoaba maw. Trends in Organized Crime. 2021;24(4):526–546.

8. Earth League International (ELI). The Totoaba Supply Chain. ELI. 2018. Available at: https://earthleagueinternational.org/wp-content/uploads/2018/07/EAL-Operation-Fake-Gold-Final.pdf.

9. NOAA. Critically Endangered Vaquita Porpoise Not Doomed to Extinction by Inbreeding Depression. NOAA Fisheries. 2022. Available at: https://www.fisheries.noaa.gov/feature-story/critically-endangered-vaquita-porpoise-not-doomed-extinction-inbreeding-depression.