Many scientists believed it was extinct. vaquita dolphin fish, the world’s most endangered marine mammal. Again almost a dozen copies leftheifers resist losing. What’s more: new research shows that few survivors they are breeding. And even seems to have developed ways to avoid gill netsThe biggest danger they face, because these fishing tackles destroyed them until recently.
All projections made in recent years showed that: vaquita must have been extinct by now. But the study, conducted by the University of Saint Andrews in Scotland and other academic institutions from Mexico, the United States and the United Kingdom, and published in the ‘Endangered Species Survey’, opens up a window of hope.
Although research documents high level of illegal fishing In the last small fort of Mexico’s vaquita marina, it puts species survival at greater risk, he also suggests: surviving specimens may have learned to free themselves from gill nets.
“Given the rapid declines detected in previous censuses, it is a surprise to find any gaps in the (study) field. These survivors are the future of a species endemic to Mexico and must be protected.‘ shouts Lorenzo Rojas-Bracho, lead author of the investigation.
Scientists estimate that between 7 and 15 vaquitas were observed in 2019 and between five and 13 in 2021, with calves being sighted in both cases. Previous research had estimated that fewer than 20 individuals remained in 2018, with the population decreasing by about 50 percent per year.
The goal is to avoid the gill nets
With all this data, experts assumed that the heifer would not survive extinction. “It seems miraculous to watch these survivors “Given the almost certain increase in the number of gill nets known to be the only threat to the species,” the researchers write.
Artisanal fishermen use gill nets to catch shrimp and fish, but they can also catch and suffocate vaquita dolphins.
Scientists underline that The only way to save this iconic species is to prevent the establishment of gill nets in the small area where these tiny porpoises are located., in the upper part of the Gulf of California. That’s the purpose.
The report containing the results of the researches, until the time when the fishermen can make a living without using nets, extinction is “inevitable”. They point out that there is alternative fishing gear this does not circulate the vaquita, but their implementation requires “additional investment, effort and complianceIn the studies conducted in recent years, the use of any of these alternative hunting tools has not been found.
“Despite everything, We still have one last chance to save the vaquita“Let’s give these animals a chance and they might survive,” adds Barbara Taylor, co-author of the paper.
The research used an established method called ‘expert inference’ to determine the number of individual vaquita dolphins seen in multiple censuses in 2019 and 2021, concentrated in an area of 12 by 24 square kilometers where nearly all detections were made. in recent years.
A “very ingenious” animal
The number of individuals seen can be taken as an estimate of the minimum population size. “There is not enough information to determine a more precise total population size,” the scientists agree.
Len Thomas of the University of Saint Andrews, who conducted the expert research with Cormac Booth, states that in the absence of direct data, “expert opinion is the next best thing to provide the quantiles used for decision making.”
Scientists have identified clues that suggest this. some vaquitas may have learned to avoid gill nets: They seemed to avoid them during a 2017 effort to protect other animals in captivity. Some also bore traces of previous gillnet encounters they had survived.
“If you kill 99 percent of the animals, the remaining one percent is probably not random.. Models do not necessarily take into account: intelligence vaquitas that may have learned to escape through their gill nets,” says Taylor.
“This may help prevent the extinction of the species, it will take a little longer, but the vaquita is not far from extinction, as the gill nets are still the main way of making a living in nearby towns, and even protecting the small area where the vaquitas are staying seems beyond the capabilities of the application,” said the researcher. detailing.
“Until fishermen have access to alternatives to gill nets and receive training in these nets, vaquita extinction is guaranteed.“, Add.
“Vaquitas are very dexterous and will recover if we stop killing them.. Mexico has all the ‘contents’ for management actions that prevent this species from extinction and its long-term recovery,” concludes Rojas-Bracho.
Reference work: https://www.int-res.com/abstracts/esr/v48/p225-234/