2023-04-11 04:31:12
Researchers from Conicet and the San Juan Bosco National University of Patagonia carried out a population census of Sei whales after reporting several sightings on the beaches of Rada Tilly, Chubut province, in recent years. It is the third largest whale in the world, measuring about 18 meters and can weigh up to 30 tons. To achieve the objective, they carried out a series of flights over the coastal zone of Golfo San Jorge. Because of hunting, which had its heyday from the 19th century, it was on the verge of extinction and that is why there is not much information about it. To this day, the International Union for Conservation of Nature considers it endangered.
“During the last 100 years not many specimens have been observed. Although historical records show that this whale was here before the hunts, The number and frequency with which they are appearing today is surprising.”, comments Mariano CoscarellaConicet researcher at the Center for the Study of Marine Systems.
an unknown species
“It struck us that there were so many of these whales in the region, but we understood why they come here once we began to study their behavior”, explains the scientist. The San Jorge Gulf is a productive area and from March there are many lobsters, a small crustacean that the Sei feed on. In addition, he clarifies: “We have not seen copulations or births. It is not an area where they come to give birth, but they do come to eat at this time of year. They have a way of feeding that is called by ramming; the animal opens its mouth and its throat expands. We were able to observe groups of up to 10 whales eating simultaneously on the same school”.
In turn, the reappearance of this species forced the work team to redirect their usual research. One of the new questions that arose has to do with the biological and family ties of other Sei that inhabit nearby places. “We do not know if they are the same ones that are in Antarctica or in Chile. They are probably related to those in the Malvinas and on the coast of Tierra del Fuegobecause they began to appear in those regions more or less at the same time that they began to visit our coasts”, he details.
cetacean observatory
The Punta Marqués Protected Natural Area is located in the extreme southeast of the province of Chubut, south of the town of Rada Tilly, and is located in the central area of Golfo San Jorge. Many species of cetaceans arrive there such as bottlenose dolphins, dark dolphins, bottlenose dolphins, gray dolphins, sperm whales, blue and humpback whales.
However, the researcher points out that the most abundant of all is the Sei whale. “They can be seen practically all year round, except between July and September when there are hardly any. From there, they can be observed more and more frequently and reach their maximum in May.. We came to count 70 specimens in the same place, with the naked eye ”, he describes.
The period of the year in which this whale visits the region makes Chubut occupy a privileged place from the point of view of nature tourism. In the months in which the frequency of sightings of Sei begins to decrease, 450 kilometers away, in the city of Puerto Madryn begins the peak of the visit of the Right Whale. So, the province has these fabulous animals all year round.
Indiscriminate hunting
According to Coscarella, Based on the analysis of records and period documents, between the end of the 19th century and the beginning of the 20th century, it is estimated that about 100,000 Sei were hunted worldwide.. Whales and other marine animals, such as wolves and elephants, were exploited for many years, because their fat had a high commercial interest and was used, among other things, in oil lamps.
Over the years, as technology and hunting gear improved, the number of whales caught increased to the point that, at different times, different species were on the verge of extinction. After the signing of the International Convention for the Regulation of Whaling in 1946 and the hunting moratorium policies implemented in 1986 by the International Whaling Commission (added to national laws and public policies), some whale species, such as the Sei , recovered their populations to a greater or lesser degree. Having a census is key: after all, counting is also knowing.
#Specialists #carried #census #estimate #population #endangered #species #whale #largest #world