Very interesting. I heard a bit about it on the news the other day but thought it said that since the end of the civil war - and of intensive poaching - the balance had started to swing back but possibly I misheard it. Of course the males are still under threat even if all females went tusk-less and as the article mentions it does restrict their own diet options.
Take a good look at this animal. If you don't know it yet, learn its name, the vaquita. On a map, find the Sea of Cortez, the Mexican waters in the northern Gulf of California where it can still be found. Remember those facts, because in a few years, the marine mammal, the smallest still existing, will probably have disappeared. From a few thousand to a few hundred between the 1970s and 1990s, its population has continued to decline. In 2019, a Mexican study found yet another 98% drop over the previous decade and estimated the total number of survivors at around 20. In a paper published on Thursday, May 5 in Science, U.S. and Mexican researchers reported that, according to the census conducted in 2021, that number has been halved again.
The cause of the tragedy is known: human greed. Their stupidity too. Long threatened by pollution and oil exploration, the vaquita is now the collateral victim of totoaba fishing. The fish – also a protected species – is at the heart of a highly profitable traffic. Its swim bladder, a valuable asset in Chinese medicine, is sold at colossal prices (more than 40,000 euros according to the latest estimates). The poachers' gillnets become death traps for the vaquitas. "However, its extinction is not an inevitability. The survival of the species is entirely in our hands," said Phillip Morin, a researcher at the U.S. National Oceanic and Atmospheric Administration and one of the authors of the Science article.
Very low genetic diversity The scientist supported his assertion based on the main result of the study, namely that inbreeding does not actually condemn the species. The study's aim was "to evaluate the extinction risk of the vaquita in the light of its low genetic diversity and the expected inbreeding," said Jacqueline Robinson (University of California in San Francisco), the article's first author. The team analyzed samples from 20 vaquitas who lived between 1985 and 2017 and sequenced their complete genome. Since marine mammals, like us, have a father and a mother, they were able to observe differences between those two genetic sources. They also managed to compare the genomes themselves and analyzed the areas of variation. Their conclusion is clear: Vaquitas have a very low genetic diversity. "On average, [it's] 10 times less than ours and less than the 11 species of whales, dolphins and porpoises to which we compared them," said Ms. Robinson . But the diversity hasn't evolved much over the years.
Above all, the species has a particularly low proportion of unfavorable mutations that could lead to its disappearance. Chris Kyriazis (University of California, Los Angeles) said, "The reason for this is its historically low population, less than 5,000 for tens of thousands of years according to our analyses. This has allowed the vaquita to gradually purge the genome of harmful mutations without excessively harming the species and puts it in a theoretically ideal situation to bounce back."
Several species have had this kind of success story: the island gray fox on the Pacific Channel Islands, the California condor, the whooping crane in North America and the Mauritius kestrel. Does the vaquita stand a chance? American researchers have made a prediction: If bycatch ceased completely, the risk of extinction would drop to only 6%. It would drop to 27% if only 10% of current catches remained and 62% with a 20% bycatch rate. In other words, like the Yangtze River dolphin before it, the "little cow" of the Pacific appears well and truly doomed.
The wild rodent – classified as 'critically endangered' – has been surviving for more than 10 years thanks to the continual reintroduction of farmed animals. A long battle with an uncertain future.
A curious hunt took place on May 13, in the town of Geispolsheim, a few kilometers from Strasbourg. Under a gray sky, legs moving through wheat wettened by the first rains of the month, the beaters advanced. Spaced a few meters apart, they beat plastic containers with sticks. A choreography all the stranger because the noise was largely drowned out by the cars on the Strasbourg-Mulhouse highway, which borders the plot of land. But human ears are not the object of this operation. "This is a prerequisite for the release of the hamsters," said Marie Frolinger, head of conservation at the Naturoparc in Hunawihr in the Haut-Rhin department, close to Switzerland and Germany. Ms. Frolinger was coordinating the troops on the ground this morning. "We make sure that there are no foxes or other predators on the plot. Then we proceed to the release. Be careful not to crush the wheat too much, especially around the pre-burrows, otherwise the rodents will be too easy a target for birds of prey. And beware of bites, these are wild animals. Next, we'll run electricity through the fences."
Around her, everyone is listening, even if almost all of them know the score. Not the forest ranger, who took up his post last year, nor the road workers, who prepared the pre-burrows. But most of the others are on their third, fifth or even tenth release. Everyone has showed up for the first of the four releases of the season, which will set a total of 500 rodents free: various government services, the chamber of agriculture, the owners of the plots, the scientists involved in the program, employees of the various breeding farms and even a German TV channel, eager to compare French methods for repopulating the endangered species with those applied on the other side of the Rhine.
Once the hunt is over, the essential operation begins. In groups of three or four, the crew walks the length of the plot. Orange stakes indicate the location of the pre-burrows, dug to receive the animals. One vertical hole, another one slanting, as the species is accustomed to do. "This is to give them an initial shelter and get them used to the outside, later they will go and dig their hole elsewhere," said Fabrice Capber, the vet who supervises the breeding.
From the "skewer" where they are suspended, a first cage is unhooked, turned over, then the bottom is opened. More or less willingly, the rodents fall into the 80-centimeter hole, where a few kibbles, a piece of apple and a carrot await them. The more reluctant ones are given a nudge, or rather a blow on the snout. "I was bitten once, I ended up in the emergency room, I won't be fooled again," said Mr. Capber. Two clods of earth are used to block the burrow, which the most daring will break through after a few minutes, others after several patient hours or more.
And we move on to the next. One male, one female, alternating, siblings never in close proximity, all fitted with an identification chip. "We want to increase the chances of reproduction and avoid the risk of inbreeding," said Caroline Habold, director of research at the Centre National de la Recherche Scientifique (CNRS), France’s state research organization, who has been involved for ten years in this last-ditch attempt to save the wild hamster by strengthening its population. It is also an opportunity to study its behavior and physiology in the lab.