'World Oceans Day' Featured Story: 65 Days After Being Released, Rescued Sea Turtles Reveal Clues to Migration Routes and Habitats

  Today, June 8, is World Oceans Day, and sea turtle research in Taiwan is continuing to make tremendous strides forward! The Forestry Bureau provides funding to a team from the National Taiwan Ocean University (NTOC) to carry out rescue operations for stranded sea turtles. One turtle in particular, a subadult hawksbill turtle named "Calamari", was carefully nurtured back to health and released back into the wild by the team on March 29, 2018. Calamari was fitted with a GPS tracking device on its shell by NTOC professor I-Jiunn Cheng with the hope that it would be able to transmit useful data back to researchers which could shed light on the hawksbill turtle's mysterious migration route and other habitat information. After being tracked for 65 days, on the eve of World Oceans Day, Calamari sent back its final GPS signal, showing that it was in the waters off the coast of Samar Island near Southern Luzon in the Philippines. To date, researchers have tracked a total of 3,572 kilometers of the turtle's extraordinary migration journey, and this data also provides important clues regarding two particular subjects: First, the data reveals that hawksbill turtles have an exceptionally longer migration route compared to the green sea turtle. Second, the data strongly suggests that tropical coral reefs serve as the hawksbill turtle's primary feeding grounds, indicating that the fate of hawksbill turtle populations is closely intertwined with coral reef ecosystems.

  This marks yet another successful case in Taiwan of rehabilitating, tagging, and releasing a sick hawksbill turtle which was a tremendous boon for helping uncover ecological mysteries of the hawksbill turtle. The fact that Calamari is still safe and happily swimming in the ocean is also great news which testifies to Taiwan's hard work and achievements in the area of marine wildlife release and conservation!

Critically Endangered Sea Turtles Face Many Threats to Their Survival, But a 'Sea Turtle Rescue Network' Is Boosting Survival Rates

  According to the Forestry Bureau, cold and warm ocean currents converge along on the east and west coasts of Taiwan, allowing a rich marine ecosystem to thrive. In fact, out of the seven species comprising two families and six genera of the planet's sea turtles, five species — green sea turtles, loggerhead sea turtles, hawksbill turtles, olive ridley sea turtles, and leatherback turtles — can be found in the territorial waters of Taiwan, making it a critically important marine habitat for sea turtles. The hawksbill turtle, in particular, lives in tropical and subtropical ocean areas throughout the world. However, the beautiful patterns on its shell have made it a long sought-after decorative item, and this species of turtle has been actively hunted since ancient times. It has an extremely small population spread around the planet and is constantly under threat of extinction. In addition, sea turtles frequently sustain injuries related to the fishing industry such as incidental capture (known as bycatch) and being accidentally hit by boats, putting additional pressure on their continued survival. Meanwhile, climate change and ocean warming, acidification, pollution, plastic waste, and other environmental issues are also causing serious harm.
  Under the Wildlife Conservation Act, the hawksbill turtle is a protected endangered wildlife species, and it is also listed as Critically Endangered (CR A2bd) by the International Union for Conservation of Nature (IUCN). In order to protect these critically endangered sea turtles, the Forestry Bureau has helped set up and fund a "Sea Turtle Rescue Network" which is separately administered in the north by National Taiwan Ocean University and the National Museum of Marine Biology and Aquarium in the south. Upon receiving a report from the general public or a coast guard unit, the Rescue Network immediately dispatches specially trained students and volunteers to provide assistance. Since 2014, the Rescue Network has handled 664 rescue missions, among which approximately 20% involve stranded turtles which were found alive, and upwards of 90% of rehabilitated sea turtles are successfully released back into the ocean.

After Being Rescued, "Calamari" Was Tagged and Released, Providing Insights into the Ecological Mysteries of the Hawksbill Turtle

  On December 4, 2017, a fisherman in Nanfang'ao, Yilan County discovered a stranded subadult hawksbill turtle which had washed ashore. After being alerted, the NTOU Sea Turtle Rescue Team came to the rescue and transported the turtle to the National Taiwan University Veterinary Hospital for evaluation and treatment. While waiting for the turtle to be admitted to the hospital, one of the Rescue Team member's was snacking on dried calamari, so the team decided to name the turtle "Calamari". Upon examining the turtle, a veterinarian discovered bits of man-made objects, such as fishing line, lodged in Calamari's stomach, and the turtle showed signs of being dehydrated, weak, and in poor health. After performing a blood test, the turtle was found to have a high white blood cell count and elevated creatinine level, indicating that the turtle was suffering from an infection. Calamari was subsequently entrusted to the care of the NTOU Sea Turtle Rescue Team, and after gradually eliminating sand particles and other foreign objects from its digestive system; the turtle finally regained its health.

  After nearly four months spent nursing Calamari back to health, the team determined that the turtle was healthy again. On March 29, 2018, the team brought Calamari out to Wai'ao Beach in Yilan county, NTOC professor I-Jiunn Cheng fastened a satellite tracking device onto its shell, and the turtle was successfully released back into the wild. At long last, as representatives of the Yilan County Government, NTOU Sea Turtle Rescue Team members, and devotees of the Buddhist organization Bliss and Wisdom looked on and bid farewell, Calamari slowly waded out into the ocean and began swimming in the direction of Turtle Island.

  After a 65-day oceanic voyage, Calamari reached the coastal waters of the Philippines between Samar Island and Southern Luzon. During its 65-day migration, Calamari visited Japan's Ishigaki Island for two days from April 10–12. After swimming around the island, the turtle continued on its way southward through the Western Pacific until it eventually reached the territorial waters of the Philippines.

  According to Professor I-Jiunn Cheng, two years ago, in 2016, an adult female hawksbill turtle named Afei was also released back into the wild. After being released in Yilan, Afei swam through the Taiwan Strait along the continental shelf for a total of 5,467 kilometers, eventually reaching the Karimata Strait off the coast of the Indonesian island of Belitung. Calamari, on the other hand, was observed to have swum southward through the oceanic zone, covering a total of 3,572 kilometers. After analyzing the satellite tracking data, researchers concluded that this area was likely Calamari's feeding grounds. Data from these two hawksbill turtles revealed previously unknown ecological habits including the turtles' "long-range migration" and "reliance on tropical coral reef ecosystems". The turtles recorded an average migration speed of 2.1 km/hr, showing that they swim faster and migrate further than green sea turtles. The data also show that these hawksbill turtles have very different ecological habits in terms of the kinds of seaweed they eat as compared to green sea turtles. Nevertheless, Afei and Calamari were found to have taken entirely different migration routes, and more research data will be needed to better understand their migration patterns.

Help Protect Our Oceans, and Always Report Stranded Animals to Authorities

  The ocean is a source of life and an important environment for nurturing marine creatures. When people engage in careless behavior such as throwing plastic trash and old fishing nets into the ocean, these things often end up in the stomachs of unwitting marine life or cause them to get tangled up, causing injury and death. In fact, this is now one of the main reasons that cetaceans (whales, dolphins, and porpoises) and sea turtles become stranded. Therefore, it is critical that we all pay attention to this issue starting with our own behavior, including generating less garbage and not littering. By working together, we can help protect Taiwan's precious marine environment.

  The Forestry Bureau reminds the general public that they should immediately call the Coast Guard Administration's 118 hotline to report any stranded sea turtles found along the coast. In the north, individuals can call the National Taiwan Ocean University (NTOU) Sea Turtle Rehabilitation Hotline (0978-952145); in the south, individuals can notify the National Museum of Marine Biology and Aquarium (08-8825001#5052). Both organizations have specially trained students and volunteers who can provide assistance. Fishermen are likewise asked to please bring any sea turtles which have accidentally gotten caught in their equipment (bycatch) back to port and notify their nearest coast guard unit.
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Visit counts:1153 Last updated on:2021-10-21