A study found that the size of Megavish in the Mekong River has been worrying in recent years due to overfishing. The length of the largest and most extreme fresh water giants, some of which are large as gray bears, decreased by 40 % in seven years.
Some fish, such as the mekong giant fish, have been studied, for more than a longer period and a decrease in the weight of 55 % in the past 25 years, as it has decreased from 180 kg (397 lbs) to 80 kg.
One of the study team, NGOR PENG BUN, helped hunt the giant catfish in 2000 weighing 270 kg, before marking it and launching it. He said, “It was enormous – unforgettable,” and he almost touched his boat. Species, known in Khmer as Trey Reach, or Royal Fish, are now for the previous.
The giant Barb, the largest carp and carp fish in the world, showed a similar path. Both types are threatened with extinction.
Scientists said the size is a matter of survival because large fish – which are likely to be arrested – produce more eggs. Cellow thickness can produce 300 kg from 10 to 20 times more offspring than a 50 kg fish, for example. Many of the largest species are also long -term and slow to maturity, which means that the increases in deaths can raise the balance towards population collapse.
The giants giants are decisive for the river’s ecosystem, but also essential in ways of living millions of people who depend on hunting. Scientists have found a sign of hope when Fischer signed in 2022 and issued a standard record of 300 kg. He was The largest fish in freshwater ever And it showed that some of the giants are still.
Hunting and hunting It often targets the largest animals It has reduced many species, including cod in the Baltic Sea and Salmon in Alaska SharksAnd it led to Smaller fangs in African elephants.
Dr. Zeeb Hogan, Associate Professor of Researcher at Nevada University in the United States and part of the study team, said that the huge Mekong shrinkage was surprising and shocking.
“We have seen this style in Atlantic fisheries, as it removed contracts of selective hunting, the largest fertile fish, which led [the Mekong] Hogan said that the risk in fish that enter the “vortex of death”, as the population is no longer viable.
“The knowledge of these giants is shrinking, whether in size and number, is similar to the loss of a small piece of Cambodia itself. Their presence carries a deep cultural or environmental importance,” said Sophorn Uy, at the Royal University of Agriculture in Bennah and also part of the team.
The study is Posted in Biological Conservation MagazineSeven years of data monitoring of 23 sites in the lower Mekong Basin included 257 species of fish. The full data was available from 2007-14. Hogan said the shrinking trend is likely to continue.
In addition to overfishing, Mekong Megafish is struggling with dams, which prevent their migration to spawning lands; Climate crisis, which disturbs seasonal temperature and rains; And the destruction of the forests that were flooded by the water seasonal, which is an important homeland.
Hogan said: “300 kilograms of Stingray explained to us that it has not been too late. There are still new records. But it only means little unless we behave now to protect these types and the river system they call home.
STINGRAY was placed and followed for two years, which was spent in a protected area over the length of 3 miles (5 km) of the river. “Contact [along rivers] “And the protected habitat – this is the Holy Jass. If you have these, these fish can live,” said Hogan.
Scientists said that fishing Megafish is already illegal in some countries where Mekong flows, but the application still represents a major challenge. “Local fishermen were necessary to collect our data,” said Sophorn. “They are on the front lines and they should be part of the solution.”