Thailand Shark Sampling Expedition

Articles about the Thailand Shark Sampling expedition in 2012,  by Shin Arunrugtichai

 

Introduction

A Black Tip Reef Shark on Koh Tao

A Black Tip Reef Shark on Koh Tao

Sharks, the selachimorphs, are the kinds of the sea, one of the most important, yet also most threatened animals in the ocean. This group of fish as been my personal favorite since childhood. Sharks are the apex predators, taking the role to regulate the prey population all the way down in the food chain. Moreover their morphology is well evolved (I will write about this in detail in future articles), and has hardly changed at all in the last 450 million years, even before the mass extinction in Cretaceous period, the era where T-Rex roams the land! There are many interesting points to talk about them, but let’s just cut to the chase, they are just awesome, which makes me want to dedicate my life for shark research.

 

Still, shark research in Thailand is still lacking, there are only a few scientific papers on sharks that has been published, so there are still many things that we do not know about them here in Thailand. Why do we need to learn more about them? As some of you may know, the population of many species of sharks has dramatically plummeted down in the last two decades, some of them even reduced to 1% of the original population. In a recent report by the IUCN, it was stated that 90% of the world’s total shark poulatioin has been lost in the last 100 years.  Therefore it is very important to have the information on various angles on sharks to come up with proper management plans to conserve them.

Taking a DNA sample from a landed shark in Ranong, Thailand

Taking a DNA sample from a landed shark in Ranong, Thailand

This series of articles is about the genetic sampling expedition for DNA mapping study in collaboration with Chinese Shark research program. Many shark species are very similar, and mis-identification is very common. Therefore by this study will help fixing the mis-identification in our database, telling us what do we have in our water, and also explaining the evolution of shark species, clarifying which species evolved from another species, which will make us understand more about their evolution. Also I did some extra work on market research, collecting the data on sharks species landed in the piers in Southern Thailand, which will be contributed to the database on shark fishery here, which hopefully will be a small grain of sand along the road leading to conservation of these amazing fishes.

 

Chapter 1: Songkla Province

Between mid-December to mid-January 2012, I was traveling around the Southern provinces of Thailand to collect samples with Dr. Xiao Chen, a Chinese researcher who is working on Phylogenetic and population genetic of Elasmobranchii (Sharks and Rays) from the suggestion of Dr. James True from Prince of Songkla University. We departed from Bangkok to Haad Yai in the stormy night when a big monsoon was hitting Songkla to settle in the department of Biology at Prince of Songkla University.

Our objective is very simple, just get the most tissue samples as possible from as many species of sharks and rays that we can get our hands on in the fishing piers. Dr.Wut, a coral reef ecologist from Coral Reef Research Unit from Prince of Songkla university picked us up from the pier on our arrival and as you might have already guessed, informed us about the bad news which is the unexpected monsoon, which prevents local fishing boats to leave or land their catches at the fishing port. So we just spent the first day’s entire morning planning our journey to visit the major ports in Southern Thailand with countless useful advices from Dr.Wut in the laboratory under the monsoon rain, but the rain stopped in the afternoon so we tried our lucks at the Songkla fishing port.

Shark by-catch from trawling fishing, from the Songkla Pier

Shark by-catch from trawling fishing, from the Songkla Pier

When we arrived at the port there were no fish left in the main landing area of the pier (most of the time, the catches are landed and sold in the morning), however we spotted some buckets left by the roadside so we checked them out. It turned out that those buckets are full of small species of sharks, namely Coral Catshark (Atelomycterus marmoratus), and Brownbanded Bamboo Sharks (Chiloscyllium punctatum). These 2 particular species are benthic species that are usually dwell in the rock crevices in the reefs. It means that they were caught by bottom trawling, which is dragging weighted nets along the seabed. In the coral reefs, trawlers entangle everything on the bottom and destroy ecosystems in its’ path, a very destructive fishing methods, which is still widely used by Thai fishing fleets and some local fishermen.

According to the fishermen and traders that I got to converse with during this trip, most of the big trawling fleets operate outside Thailand territories, where the natural resources are still rich, such as Burma and Indonesia. Since “there is nothing left in Thailand” as they usually say. However there are still many trawlers in the Thai waters (we also have this problem at major dive sites around Koh Tao once in every few months even in the protected areas) especially in the Gulf of Thailand. Trawling is very destructive, not only destroying the fragile and slow growing ecosystems such as coral reefs or sea mounts, but it is also causing another problem, by-catch.

Juvenile sharks never even given a chance at life.

Juvenile sharks never even given a chance at life.

By-catch is the term used for unwanted fish that are caught in the nets, which usually have low commercial value, some are even inedible. However the ratio of these by-catch are generally overshadow the commercial species caught in the same trawling session, especially for shrimp trawling which the ratio could reach 20 : 1 for unwanted species against the targeted species. Basically what this means is that for every animal that you eat, 20 more had to die needlessly.

The public awareness of this issue in Thailand is growing, but has not reached the critical mass which going to trigger the change that we hope for. There is still indifference in some stakeholders, there are still flaws in the system that inhibit the efficiency of the government agencies, and there are still lack of people that are working for this cause, but I am sure it will succeed one day. I hope the zoning regulation and management that we drafted last year with the community will be cooperated by stakeholders, keeping our island healthy and to be a model site for conserving marine resources for the rest of Thailand.

 

Stay Tuned for more chapters coming soon!