He has completed almost a hundred of national and international scientific projects in biodiversity preservation in the northern range of Truong Son Chain which runs as the backbone of Vietnam.
His two museums of freshwater fish are now kept in Vu Quang National Park in the central Ha Tinh Province and Phong Nha-Ke Bang National Park in Quang Binh Province.
La Giang fish enters Red Book
Tu displayed his passion in talking about the Vu Ha fish he has the credit for adding it to the Red Book. He said, “Local people call this fish ‘ca co’ or ‘La Giang fish’, but I just gave it another name – Vu Ha.”
Pointing at the sparkling swimming school of fish in the river, he explained, “Their special biological habit is to mate in groups on the river surface in their breeding season. With sparkling white and yellow stripes, they look like they are wearing wedding gowns.”
“Vu Ha” is meant “dancing on the river”.
Tu had initially discovered the fish species in 1993 while going on a trip with Ph.D. John Mackinnon from the World Wildlife Fund (WWF) and head of the investigation team in biodiversity of Vu Quang National Park, and a forest ranger.
While they were pulling a fishing net from a river, the forest ranger showed the two scientists a beautiful pink sparkling fish, which would go on to be called a La Giang fish afterwards. As Tu uttered excitedly, “This is a new species of fish,” Dr. Mackinnon said doubtfully, “It is new to you, but is it so easy to discover a new species of fish for the world?”
Undeterred by Mackinnon’s reply, Tu started his own long-time journey to prove that the La Giang is a new species of fish. From 1993 to 1995, he continuously corresponded with M. Kottlat, chief editor of the world freshwater fish journal, based in Germany.
Over the years, Kottlat required detailed information about the La Giang fish, and then in late 1995 he concluded that it was really a new kind of fish. As a result, Mackinnon gave strong support for Tu in a new project to preserve the uniqueness of the fish system in the mountainous limestone area of Phong Nha- Ke Bang. Also, the La Giang fish was listed in the Red Book in 2007 under the name “Parazacco vuquangensis, Tu, 1995”.
Ph.D. Nguyen Thai Tu and samples of freshwater museum in Phong Nha - Ke Bang (Photo: Tuoi Tre)
Einstein-style hair and beard
In a science conference in Quang Binh held by the WWF, Tu presented four stages in the emergence of a new species of fish, namely individual variation, flock variation, new subspecies formation, and finally species emergence.
An example he gave of this procedure was the emergence of “chep hoa fish” and “ton fish.” They both belong to the carp branch but never mate with each other, due to the geographic obstacles in streams that weave their ways between limestone mountains. This is an interesting example of a new species’ emergence in a small area like Phong Nha- Ke Bang, which is remarkably different from other areas of the world.
In this report, Tu also convincingly proved that Phong Nha-Ke Bang was the fourth emergence center of the Cyprinus branch of carp fish and the emergence center of the Cyprinini branch of carp fish in South East Asia.
On leaving the podium after his lecture, Tomas Dillon, chief consultant of the project, congratulated him with a joke, “Vietnamese Einstein.”
He replied humorously, “I only have hair and beard that look in the style of Einstein.”
Now at the age of 75, Tu is still pursuing research for species of freshwater fish.
“The German Development Bank is sponsoring a new project on biodiversity in Phong Nha-Ke Bang. I was asked to join the project. Maybe I will encounter a new question about a new species of fish,” he said.
That means this 75-year-old man is again starting a new journey on his endless track of scientific research.