Taiwan’s Fisheries Research Institute (FRI), in collaboration with local and Japanese universities, presented its findings on the behavioral characteristics and thermoregulation mechanisms of the shortfin mako shark on Monday.
The species of shark, classified as “endangered” by the International Union for Conservation of Nature, is one of the most common bycatches of Taiwanese commercial longline and gillnet fisheries, the FRI told a news conference.
The joint research was carried out by FRI in conjunction with Japan’s Graduate University for Advanced Studies (SOKENDAI) and National Kaohsiung University of Science and Technology.
Photo: CNA
According to SOKENDAI professor Yuki Watanabe, Taiwanese and Japanese fishers have helped to capture shortfin mako sharks and tag them with custom-made data loggers, which transmitted the data via satellite.
The loggers, which capture video recordings, monitored the sharks’ body temperatures and tracked their movements, SOKENDAI researcher Soma Tokunaga said.
Analysis of the data revealed the unique thermoregulation abilities of the shortfin mako that are not found in other shark species, one of which is the ability to regulate body temperature so that it stays warmer than the surrounding water, Tokunaga said.
When hunting prey even at depths of 1km where water temperatures are as low as 4°C to 5°C, the shark can use this ability to its advantage.
FRI Deputy Director-General Yeh Hsin-ming (葉信明) said the research also shows that the shortfin mako experiences only a slight decrease in body temperature averaging about 2°C to 4°C after each deep dive of several hundred meters.
This is vastly different to other types of shark, which typically keep themselves warm through a “countercurrent heat exchange,” where blood vessels transfer surrounding heat into the body, Yeh said.
The study found that during the day, the shortfin mako shark could be found in areas from the surface to depths of 300m and frequently crosses the thermocline, likely related to feeding behavior, FRI associate researcher Chiang Wei-chuan (江偉全) said.
At night, it prefers to inhabit depths of between 100m and 200m, Chiang added.
SOKENDAI is working on a report to publish the findings in international journals, Yeh said, adding that the research would also be presented at a scientific conference next month.
The research would serve as a useful resource for regional fisheries management organizations and others for research into the sustainability of the species, he said.
With climate change leading to variations in sea surface temperatures, the shortfin mako shark’s activity would also change, and as such, the findings could provide valuable insights for fisheries management, Tokunaga said.
Travel agencies in Taiwan are working to secure alternative flights for travelers bound for New Zealand for the Lunar New Year holiday, as Air New Zealand workers are set to strike next week. The airline said that it has confirmed that the planned industrial action by its international wide-body cabin crew would go ahead on Thursday and Friday next week. While the Auckland-based carrier pledged to take reasonable measures to mitigate the impact of the workers’ strike, an Air New Zealand flight arriving at Taipei from Auckland on Thursday and another flight departing from Taipei for Auckland on Saturday would have to
The Taipei City Government yesterday confirmed that it has negotiated a royalties of NT$12.2 billion (US$380 million) with artificial intelligence (AI) chip giant Nvidia Corp, with the earliest possible signing date set for Wednesday next week. The city has been preparing for Nvidia to build its Taiwan headquarters in Beitou-Shilin Technology Park since last year, and the project has now entered its final stage before the contract is signed. Taipei Mayor Chiang Wan-an (蔣萬安) said the city government has completed the royalty price negotiations and would now push through the remaining procedures to sign the contract before
Taipei Zoo welcomes the Lunar New Year this year through its efforts to protect an endangered species of horse native to central Asia that was once fully extinct outside of captivity. The festival ushering in the Year of the Horse would draw attention to the zoo’s four specimens of Przewalski’s horse, named for a Russian geographer who first encountered them in the late 19th century across the steppes of western Mongolia. “Visitors will look at the horses and think that since this is the Year of the Horse: ‘I want to get to know horses,’” said zookeeper Chen Yun-chieh, who has been
The Ministry of Foreign Affairs on Thursday said the name of the Taiwanese Representative Office in Lithuania was agreed by both sides, after Lithuania’s prime minister described a 2021 decision to let Taiwan set up a de facto embassy in Vilnius as a “mistake.” Lithuanian Prime Minister Inga Ruginiene, who entered office in September last year, told the Baltic News Service on Tuesday that Lithuania had begun taking “small first steps” aimed at restoring ties with Beijing. The ministry in a statement said that Taiwan and Lithuania are important partners that share the values of freedom and democracy. Since the establishment of the
RSS