Wonderful migratory fish fieldwork in Vietnam 2016

19-07-2021

Wonderful migratory fish fieldwork in Vietnam 2016

According to the addendum as a part of and contemporaneous with the MOU between Hanoi National University of Education (HNUE) and Okinawa Institute of Science and Technology School Corporation (OIST), Japan, the Vietnam trip in 2016 has just finished successfully and unforgettably. Three researchers including Dr. Ken Maeda (OIST), Dr. Midori Iida (Niigata University) and Dr. Tran Duc Hau (HNUE) made research activities in the Tien Yen River, Quang Ninh Province and some localities from Danang City including the Han River from 24^th February to 5^th March, 2016 to examine Taxonomy, life history, and population genetics of gobies in Vietnam.

In the fieldwork, fishes were collected by hand nets and by snorkeling and cast net sometimes was used at varieties of sites along the Tien Yen Rivers, and some tributaries of the Han River. Estuarine waters also belonged to our target to catch goby fishes to understand migratory pattern of this group fish that is poorly known in the continent including Vietnam. Various information on geography of the sampling sites, with respect to the pattern of the bottom as well as the current speed were noted carefully that would be very important data for the further analysis, with values in comparison with the other sampling sites.

Even during the trip the researchers actually did not have a true laboratory, a bed room could be occupied as a special location for laboratory work for us. However, many skills, such as fixation and photos taking could be performed perfectly under guide of Dr. Ken Maeda who also is as known as “Dr. Goby” because he really does like discovering migration of goby in the world. The laboratory work in Tien Yen and Danang will be endless for us as we had dozens of funny stories.

The most important impression as a part of the trip is two wonderful presentations by Dr. “Goby” and Dr. Iida with a lot of interesting results from their current studies. The seminar warmly welcomed to the Dean, Faculty of Biology (HNUE), Assoc. Prof. Dr. Nguyen Lan Hung Son who always supports this agreement on ichthyological research as well. Many ichthyologists from the university and other institutes as well as lecturers from the mentioned office also participated the seminar by their full attentions with various curious questions to the speakers. The seminar introduced overview of diadromous migration that fishes move between the sea and river during their lives. Dr. Maeda specialized in amphidromous migration, which the fish moves between the two environments not for reproduction. As we could know, he focused on some beautiful gobies, such as species of Stiphodon and Rhinogobius genera. Importantly, the aim of Vietnam trip and result from the previous visit was also a crucial part in his speech.

The next part of the seminar from Dr. Iida, who has a lot of experiences in migratory studies under Prof. Tsukamoto (the University of Tokyo) as a supervisor, the person found out the spawning ground of Japanese eels, which was published in Nature (2006). Applying otolith to elucidate habitat shifting of fish in their lives, herein the microchemistry of otolith by individuals estimated the ratios of Sr:Ca and Ba:Ca accounted for Dr. Iida’s presentation. She spent much time on talking about an amphidromous goby Sicyopterus japonicus migration and some expectations on corporations with Vietnamese scientists in investigation into some migratory fishes, such as Ayu and goby, but the machine in process the otolith reading and analyzing still remains audiences’ concerns.

The trip in 2016 ended successfully and hoping some notable results will be published in future! Thank you very much for the both Japanese researchers who always have kind considerations in ichthyological research in Vietnam. Looking forward to seeing you!