Asian scientist (Jan 23, 2019) Scientists from Japan's Tokyo University say – Whale Sharks, the world's largest fish, tolerate the period of starvation and eat more plants than previously thought. Their findings are published in the journal Ecological Monographs.
Whale sharks are filter-feeding, soft-body fish that travel to tropical oceans in search of their microscopic food. They can increase up to 12 meters long and weigh 21 metric tons, as long as the public city bus and three African elephants are as heavy. Despite their special size, there are many myths of whale sharks life in the open sea, even after discovering 183 years ago.
In the present study, researchers under the Tokyo University Environment and Ocean Research Institute, led by Mr. White White, planned a health check for whale sharks based on blood tests.
"Whale shark is not one of the same size for tourists and scientists, but also one of the most exciting creatures due to their grace and beauty. It is a special privilege to unveil some of the mysteries surrounding their lives," said Wat.
Researchers have taken almost ten milliliters of blood from the pectoral fins of whale sharks. Then they analyze blood samples immediately on the research research ship and using specialized laboratory equipment, biopsy whales detects various forms of carbon and nitrogen or isotopes inside the whistle shark tissues.
"When you visit a doctor, like blood tests, we can evaluate the health of whale sharks based on their blood-sourcing," said Wat. "We combine blood tests and tissue isotopes analyzes to make accurate health checks for animals."
There was a complete health check on eight wild whale sharks, which were accidentally released from an aquarium trap on Okinawa, Japan's coastal coast. According to blood test results, wild whales could not eat sharks for weeks or months.
However, whale sharks in coastal places are seen by eating small hunt and fish from fish to small fish and squid in hunting ranges, scientists have found that all the tested shark plants show signs of bite and significant amounts of algae.
"This is a somewhat surprising and controversial discovery, because whale sharks are generally considered to feed hard on the high levels of the food chain. However, some whale sharks have been found in their stomach with seaweed and leaving plenty of food can reduce the chances, Because our blood tests suggest, "said Watt.
Healthy diagnosis and dietary discovery can not be similar to other species, or possibly other whale shark populations, from Wild Okinawan whale sharks. However, Wat is hoping that a complete health check approach will be used to investigate the possibility of starvation, personal specialists and unwanted food selection in various dangerous marine animals.
This article can be found here: Wat et al. (2019) Using multi-tissue, Multi-Isotope Approach to enhance insight into the foregoing specialization in the world's largest fish.
Source: University of Tokyo; Photo: K. Saito / Okinawa Churashima Foundation Research Center
Disclaimer: This article does not necessarily reflect the views of Asian scientists or its staff.