A whale that wandered into the mouth of the Yodo River in Osaka Bay attracted attention. In recent years, a series of unusual occurrences in marine life have been reported in the waters around Japan. Large sharks like this one have also moved north from their natural habitat, causing serious damage to fisheries.
▽Whale in the mouth of the Yodo River…Large sharks in the Seto Inland Sea On the 9th, a 15-meter-long sperm whale was discovered in the mouth of the Yodo River in Osaka. The day before yesterday, on the 13th, experts confirmed that it was dead. Experts believe that it had become separated from its pod for some reason, but the exact reason is still unknown. Something unusual is happening in the seas around Japan right now. Today, the 15th, a giant squid, which lives in the deep sea, washed ashore on the coast of Iwami Town, Tottori Prefecture. It measured 3.2 meters in length. Furthermore, in June of last year, a oarfish was also found in the same Iwami Town.
(Reporter Taisuke Ikegawa) “This is it. That’s an incredible amount of pufferfish.” A large number of pufferfish were washed ashore on the beach. And what has become a problem in recent years is… sharks. This is a great white shark, approximately 4 meters long, that was caught in a fishing net in the Seto Inland Sea last May. It is a ferocious shark that is said to attack humans and was the model for the movie “Jaws,” and it is rare for a great white shark to appear in the Seto Inland Sea. In Okinawa, a shark over 2 meters long was spotted at a swimming beach. This shark was caught on a fisherman’s hook. After a struggle of about an hour, it was finally pulled up using a rope. There have been a series of shark sightings in this area. Amami Oshima, Kagoshima Prefecture. This area has also been troubled by shark attacks in recent years.
(Hidekazu Beppu, Amami Surfing Federation) “This is the beach where the sharks appeared. There were three sharks, about 2 meters long.” The sharks were attracted to the carcass of a whale that had washed ashore in the shallows. (Hidekazu Beppu) “There have been occasional sightings of sharks coming into the shallows even though they are not usually there. There is a disaster prevention radio in Tatsugo Town that says, ‘Please be careful of sharks.'” This is a nationally famous surf spot. There are many surfers and tourists, and there are concerns about the impact on tourism. ▽ “Sharks are biting nets used for aquaculture…” Fisheries are suffering from even more serious damage.
(Kiyotaka Suwahara, fisherman) “Fishing is not viable. They bite into nets used for aquaculture, and sharks are everywhere, even in shallow waters.” In recent years, the amount of fish caught has decreased significantly due to shark damage. When they pulled up the nets… “There are sharks.” And then, “Another shark.” On this day, three sharks were caught in the nets. These sharks are tiger sharks and blacktip reef sharks, which sometimes attack humans. On some days, sharks measuring 4 to 5 meters in length and weighing 300 kg are caught.
(Mr. Suwahara’s wife) “Sharks come from all over. There weren’t this many before.” Q. They’re eating the nets, aren’t they? “That’s why they tear.” Sharks not only eat other fish, but they also bite through nets like these, causing significant damage to fisheries. In Amami Oshima, many people involved in the fishing industry have complained about the damage caused by sharks, so the government is using subsidies to carry out shark culling.
(Yoshito Tanaka, representative of Sumiyo Fishing Village, which is carrying out shark culling) “We want to cull the sharks in a way that prevents their numbers from increasing any further. The fish population is decreasing, and there are sharks when you go fishing, so it’s becoming increasingly difficult for fishermen to make a living from fishing due to the damage.” Why is the damage from sharks increasing, according to experts?
(Professor Emeritus Kazuhiro Nakatani of Hokkaido University, an expert on shark ecology) “It must be global warming. I can’t think of anything else. It’s quite possible that sharks that are in the south are coming up due to global warming. After all, they come in search of food.” Professor Nakatani points out that as seawater temperatures rise due to global warming, the habitats of the fish that serve as their food have also changed, and it is possible that sharks have been drawn northward as a result. Q. Are seawater temperatures high? (Chairman Katsuki Oki of the Amami Marine Biology Research Association) “Yes, they are about 1 to 1.5 degrees Celsius higher than usual.” Katsuki Oki conducts research on coral reef conservation and the ecology of marine organisms on Amami Oshima. Mr. Oki points out that in response to rapid global warming, we have reached a stage where we must not only take measures but also adapt to the environment.
(Katsuki Oki, Chairman of the Amami Marine Life Research Association) “When the environment is different, trying to force things that can’t survive there back into the environment doesn’t always work, so we have to think about various things that are suited to that environment.” From “Sunday Station” on January 15 [TV Asahi News]
