This is an account of the second phase (1964–1965) of a project -which originally started in 1963 - concerned with inland fishery investigations, management and training in Thailand, carried on under the Expanded Program of Technical Assistance (EPTA) of the Food and Agriculture Organization of the United Nations (FAO). The second phase was conducted by Dr. Arthur W. Witt, Jr. (U.S.A.), FAO/EPTA Inland Fisheries Biologist, during the period of 1 August 1964 to 31 July 1965.
The background of this project has been related in FAO/UN (1965), but it may be useful to present a brief sketch of the forerunners of the present project.
The first FAO fisheries mission to Thailand occurred in 1948, when Drs. K.F. Vaas and J. Reuter made a brief survey of the fisheries from 1 November to 13 December. The former considered the freshwater fisheries while the latter dealt with marine fisheries. A number of sound recommendations were made in the report, FAO Fisheries Mission to Thailand (1949).
In 1951 the Government of Thailand requested technical assistance in fisheries from FAO under EPTA, and in response to the request, Dr. S.W. Ling, FAO/EPTA Fishery Biologist was detailed to serve with the Thai Division of Inland Fisheries in a program of inland fisheries development. During his stay (1951–54), he developed the extension program and markedly accelerated the country's program of fish culture. His report (Ling, 1957) contains many sound recommendations to the Department of Fisheries.
In 1962, the Government again requested technical assistance from FAO - this time a project concerned primarily with establishing a program of inland fishery investigations. In 1963, Dr. R.W. Larimore was assigned as FAO/EPTA Inland Fisheries Biologist to advise and assist the Government in this program. He served in Thailand from 25 July 1963 to 6 June 1964, and the report based on his work (FAO/UN, 1965) also contains a sound body of recommendations. (It has been studied thoroughly by the present expert - see below - who concurs whole-heartedly with its recommendations.)
With the repatriation of Dr. Larimore, Dr. Arthur W. Witt, Jr. (U.S.A.) was next assigned to continue the project under the same general terms of reference.
The objectives of the technical assistance program were to assist the Division of Inland Fisheries to develop:
training programs for technical personnel.
After assessment of the present policies, management practices, and research activities, the major problems of Thailand's inland fisheries were to be listed and plans drawn up for their solution. Plans were to be developed for:
The FAO expert was to serve in an advisory capacity, and make every effort to see that the work he initiated would be continued after the term of assistance.
Dr. Witt left his post with the Co-operative Fishery Unit, University of Missouri, Columbia, Missouri, on 1 August 1964, and arrived at FAO Headquarters, Rome, the next day to be briefed on his assignment. On 15 August he left Rome to take up his duties in Thailand with the Department of Fisheries in Bangkok.
The expert was disappointed to find that Dr. Larimore's counterpart, Mr. Ariya Sidthimunka, Senior Technical Officer, who had an intimate knowledge of the projects that he and Dr. Larimore started as well as a good knowledge of the fishery problems in Thailand, had been assigned to a school on psychological warfare for a period of three months.
Mr. Snit Tognsanga, a competent biologist, and Mr. Kitjar Jaiyen, a recent graduate from the School of Fisheries, were assigned as counterparts to the expert. These men were able, but they knew nothing of the work that Dr. Larimore had performed nor of the activities of the fisheries stations.
Mr. Ariya Sidthimunka was reassigned to the expert after the termination of the course on psychological warfare, but needless to say, valuable time had been lost.
The starting point of this project began with the laborious re-translation into English of Dr. Larimore's project plans so that the new expert could get a datum point from which to start. (The English version could not be located). Throughout the expert's stay and as stations were visited, the projects were reviewed with the biologists and station chiefs. As the expert gained knowledge of the fishery problems new projects were established. It was impossible to follow a systematic schedule in visiting the stations; actually no arrangements were made for visits to five of them.
On 4 July 1965 the expert left Bangkok for Rome for preparation of the final report. His employment was terminated on 31 July 1965.
The flow of knowledge and understanding is not in only one direction; the student learns from the teacher and the teacher learns from the student. As I have tried to impart knowledge and understanding during my stay in Thailand, I have also gained knowledge and understanding. To the people of Thailand who have been my teachers, I offer my sincere thanks.
Mr. Chertchai Amatayakul, Mr. Prida Karnasut, and Mr. Sant Bandhakut have been most helpful to me in gaining a broad understanding of administrative and fishery problems in Thailand. I have valued their counsel and acknowledge their assistance.
I owe a special debt of gratitude to my counterparts, Mr. Ariya Sidthimunka, Mr. Snit Tongsanga, and Mr. Kitjar Jaiyen. These men have been very close to me. We have shared many wonderful experiences, and they have served as my eyes and ears while in Thailand. There is a bond between us which cannot be broken.
There are many biologists and station chiefs I want to thank for the helpfulness and hospitality I enjoyed while in the field. To mention only several of them would slight the others, so to each one with whom I have had the pleasure of working and talking, thank you.
I must also mention the people of Thailand I have met, especially the fishermen. In the course of my studies I have shared their food, the comfort of their homes, and slept on their mats. They are, as are all fishermen, the salt of the earth. Needless to say, I thank them deeply, and shall always remember their sincere and generous hospitality.
Finally, I acknowledge, with warm affection, the stimulation, comfort, guidance and friendship of my colleagues at the FAO Regional Office for Asia and the Far East. To Mr. J. Alan Tubb, Dr. G.N.S. Rao, Dr. S.W. Ling, Dr. T. Yamamoto, and to Mr. Boon Indrambarya, who looked after us all - thank you very much.
There is no question but that freshwater fishes play a major role in the diet of the Thai. Fish constitutes their major source of protein. This renewable natural resource is exploited throughout the year, in all parts of the country, and through the use of a tremendous variety of gear. Fish are taken singly by hook and line, and by the thousands in huge traps in the flood fishery. Fishing activity is most intense as the flood waters are receding, a time when the Thai characteristically fish as they wait for the rice fields to dry.
At this time when fish are in abundance they are eaten fresh and are also preserved in various ways against the coming dry season when they are scarce. They are preserved by salting and air drying, dried by smoking, made into fermented fish or into the liquid known as “nam pla”. Each year with the cycle of the monsoon this resource is renewed. Thus the Thai is supplied with an abundant source of food --all he has to do is dip it from the water. Like all natural resources, this one is in danger of rapid exploitation and depletion, in the face of an increasing human population and the changing patterns of land use. Fortunately, however, this is a renewable resource, and it can continue to be productive for future generations --if this generation acts wisely and quickly.
An increasing human population imposes increasing demands on fish populations, and at the same time destroys natural habitats by irrigation schemes, agricultural and industrial growth. To offset this, and to increase fish production, we must try to: maintain and improve existing natural habitats; utilize to the utmost new waters, such as hydroelectric reservoirs and irrigation tanks; create new waters such as farm ponds; improve and increase fish cultural activities; and augment fishery extension work.
To accomplish these aims, research is required to answer certain basic questions. The findings of research can then be applied in the form of sound management practices. This must be done if the production of fish is to be maintained or increased.
After becoming familiar with the fishery program of the Department, the expert reviewed the existing projects, assisted in getting some of them underway and improved some by enlarging their scope. New projects were proposed to open important avenues of research and application, keeping in mind the practicality of the projects, their immediate value, the physical facilities available, and the technical competence of the personnel.
There follows a list of technical projects developed by Dr. Larimore and assigned to station biologists, in some cases station chiefs, for execution. The annotations, which explain the progress of the projects, are those of the present expert, Dr. Witt.
Technical Projects of the Thailand Inland Fisheries Stations, 1964
Bangkhen Fisheries Station (Bangkhen)
Breeding of Pangasius sutchi by hormone injection.
(Not done. Members of School of Fisheries will work on this 1965.)
Life history of the giant freshwater prawn, Macrobrachium rosenbergii.
(No report, but the project has been active.)
Fishing records at Ayddhaya.
(Report prepared for 1964. Data for 1965 being collected and analysed. A large amount of information has been gathered.)
Selective breeding of the common carp, Cyprinus carpio.
(Report in preparation.)
Biologists: Snit Tongsanga, Prasit Kessunchai.
(Snit transferred to Kasetsart University; Prasit, 3-month fellowship to Japan.)
Bung Borapet Fisheries Station (Nakorn Sawan)
Fisheries surveys of Bung Borapet Lake.
(Not done.)
Breeding of Pangasius sutchi by hormone injection.
(Not done.)
Fishing records at Nakorn Sawan.
(No report, but much work has been done.)
Food habits of Cyclocheilichthys enoplos and Cirrhinus microlepis.
(Not done.)
Biologist: Suchit Bhinyoying (one-year FAO Fellowship to the United States).
Nong Harn Fisheries Station (Sakol Nakorn)
Fisheries surveys of Nong Harn Lake.
(Survey completed. Report completed. Good work.)
Growth rate of marked Tilapia mossambica in irrigation tanks.
(Work completed and report prepared. Good work.)
Biologist: Somched Chulapond (Transferred to Nong Prajak at Udorn).
Kwan Payao Fisheries Station (Chiengrai)
Fisheries surveys of Kwan Payao Lake.
(Survey only partially done, but project has been dropped. No report.)
Life history of Pristolepis fasciatus.
(Present information indicates it spawns in ponds. No report.)
Biologist: Pramote Vanichakorn.
Chao Phya Fisheries Station (Chainart)
Fishing records at Chainart Dam.
(Not done.)
Fish culture in rice fields.
(Not done.)
Biologist: Dumrong Silapachai, one of Dr. Larimore's counterparts. (Transferred to Extension Section).
Maecho Fisheries Station (Chiengmai)
Fish Culture in rice fields.
(Report in preparation. Good work.)
Ecological studies of Tilapia mossambica and T. melanopleura.
(Not done.)
Biologist: Chaloemwilai Chuensri on fellowship in the United States.
Kuankut Fisheries Station (Patalung)
Surveys of aquatic animals in Patalung Lake.
(A list of fishes has been compiled.)
Biologist: Swad Boonthai.
Surin Fisheries Station (Surin)
Population studies of fish in irrigation tanks.
(Not done.)
Fish culture in rice fields.
(Work completed, and report submitted. Production of rice increased slightly when fish were cultured.)
Biologist: Nid Koocharoenphaisal.
Huoy Maung Fisheries Station (Ubolrajthani)
Fish populations of irrigation tanks.
(Work completed and report prepared. Standing crop very low: 19.8 pounds per acre.)
Introduction of new species into an irrigation tank.
(Report indicates stocked Tilapia disappeared from the irrigation tank, perhaps as a result of predation.)
Life history of important fishes.
(Not done.)
Nong Jabok Fisheries Station (Nakornrajasima)
Fish populations of irrigation tanks.
(Work finished and report completed. Tilapia disappears from the irrigation tank, perhaps as a result of predation.)
Biologist: Su-in Ritjarung.
Bhumipol Fisheries Station (Tak)
Production of fish in Bhumipol Reservoir.
(Work completed and report submitted. Good work.)
Fishing methods in Bhumipol Reservoir.
(Not done.)
Limnology of Bhumipol Reservoir.
(Not done.)
Biologist: Charoen Panil.
Bangchan Fisheries Station (Chanthaburi)
Studies of various types of shrimp (Penaeidae) farms at Chanthaburi.
(Studies completed and report prepared.)
Life history of Scylla serrata.
(Not done.)
Collection of oyster spat for rearing purposes.
(A report has been submitted.)
Ecology of Tilapia mossambica in relation to shrimp farm.
(Not done.)
Biologist: Smarm Bhumipol.
Klong Warn Fisheries Station (Prachuabkirikhan)
Growth rate of milkfish (Chanos chanos) in brackishwater ponds.
(A report has been prepared on the work. Good work.)
Efficiency of gear used for collecting milkfish fry.
(A report has been prepared.)
Biologist: Likit Nukoolrak.
The above annotations indicate that of the 32 outlined projects, 14 (44 percent) were completed and reported upon. Of the 18 remaining, 13 were not done, and there were no reports (up to July 1965) for 5. The reasons some of the projects were not done are varied, and range from lack of interest and understanding on the part of the administration and biologists, lack of equipment, lack of knowledge, to the transfer of key personnel. What was not done is of little importance; this can be remedied. What is important is that 44 percent of the projects were done, some of them were done very well, and some of them indicate minor changes that need to be made to improve the fishery program.
The following list of projects was developed for the 1965 program of research. Some of these were carried over from the 1964 program because of their importance. These combined projects should continue for a number of years. Definitive answers to complex biological problems can rarely be found in one year, even by the most competent biologists. For example, it would be impossible for a single biologist at Bhumipol Reservoir to complete the projects in the 1964 program in only one year.
Some of the projects in the 1965 program were started while the expert was still on duty. It was encouraging to see the enthusiasm of some of the new biologists, and the good work they are capable of doing.
Technical Projects of the Thailand Inland Fisheries Station, 1965
Bangkhen Fisheries Station (Bangkhen)
Induced spawning in catfish (Clarias macrocephalus) by pituitary injection.
Fishing record of flood fishery at Ayutthaya.
Selective breeding of Cyprinus carpio.
Biologist: Prasit Kessunchai.
Bung Borapet Fisheries Station (Nakorn Sawan)
Fishery survey of Bung Borapet Lake.
Fishing record of flood fishery at Nakorn Sawan.
Biologist: Khemchart Nimsomboon.
Nong Harn Fisheries Station (Sakol Nakorn)
Biological survey and fish production of Nong Harn Lake.
Preliminary study of growth rates of Tilapia mossambica and survival in natural populations.
Life history study of Osteochilus hasselti in Nong Harn Lake.
Biologist: Pipob Kamolrat.
Kwan Payao Fisheries Station (Chiengrai)
Experiments on biological weed control using herbivorous fishes.
Biologist: Chaninthorn Sritongsuk.
Chao Phya Fisheries Station (Chainart)
Fish culture in rice fields; determination of stocking rates.
Study of the growth of the giant freshwater prawn (Macrobrachium rosenbergii) in ponds.
Biologist: Boonchuay Chaopaknam.
Maecho Fisheries Station (Chiengmai)
Experimental fish culture in rice fields.
Fish population in an irrigation tank, and stocking of new species.
Biologist: Samrong Pawhorn.
Kuankut Fisheries Station (Patalung)
Survey of aquatic animals in Patalung Lake.
The effect of salinity on the distribution of fish in the upper end of Patalung Lake.
Biologist: Pramote Suwanasart.
Surin Fisheries Station (Surin)
Fish culture in rice fields.
Fish population studies in an irrigation tank and stocking of new species.
Biologist: Nid Koocharoenpisal. (Not visited in 1965).
Huoy Muang Fisheries Station (Ubolrajthani)
Evaluation of stocking Tilapia in irrigation tanks.
Evaluation of stocking Puntius gonionotus in irrigation tanks.
Biologist: Somdech Srikomut. (Not visited in 1965.)
Nong Jabok Fisheries Station (Nakornrajasima)
The value of introducing Tilapia melanopleura into irrigation tanks.
Fishery survey of irrigation tank in Nakornrajasima.
Biologist: Su-in Rithjarung.
Bhumipol Fisheries Station (Tak)
Production of fish in Bhumipol Reservoir.
Experimental fishing in Bhumipol Reservoir.
Limnology of Bhumipol Reservoir.
Biologist: Charoen Panil
Bangehan Fisheries Station (Chanthaburi)
Biologist: Smarn Bhumipol. (Not visited in 1965.)
Klong Warn Fisheries Station (Prachuabkirikhan)
Experimental culture of the oyster (Crassotrea vitrefacta).
Efficiency of gear used for collecting fry of milkfish (Chanos chanos).
Biologists: Likit Nukullak and Jamras Khantijit.
Nong Prajak Fisheries Station (Udondhani)
Experiments on biological weed control using herbivorous fishes.
Control of predaceous insects in hatchery ponds.
Biologist: Somchet Julapong.
Toong Sarng Fisheries Station (Khonkaen)
Growth rate of Cyprinus carpio in ponds.
Biological fisheries survey of Nam Pong River.
Pre-and post-impoundment study of the Nam Pong Reservoir.
Experimental fish culture in rice fields.
Biologist: Saney Polprasith.
Kaeng Lerng Charn Fisheries Station (Mahasarakarm)
Production of fish in Klanglearngjan (an irrigation tank).
Experimental fishing for predators in an irrigation tank.
Biologist: Amnuay Tantong. (Not visited in 1965.)
During the course of the expert's assignment he was asked for comments on a proposed reorganization plan for the Department of Fisheries. These comments were submitted to the Director-General of Fisheries and will not be presented in this report.
The expert would also like to comment on the question of a research budget. It was noted that within the Division of Inland Fisheries the officer in charge of research projects had no information as to the amount of money allotted to these projects.
It is suggested that the research budget be made up and expended by those persons concerned with the research.
The Station Biologist should formulate the research budget for his station and submit it to the Divisional Chief of Research who could pass or modify it and incorporate it into the Divisional research budget. This budget would then go to the Chief of the Inland Fisheries Division for incorporation in the Division Inland Fisheries budget which would be sent on through higher channels for final approval.
Upon receiving the approved budget the Chief of the Inland Fisheries Division would inform the Divisional Chief of Research who would then notify the Station Biologist of the exact amount of his approved station budget.
At the station level, the biologist would be responsible for the expenditure of the funds. This procedure would allow the research personnel to know how much money they have to work with and thus plan their work accordingly.
A contingency fund needs to be established within the Division. At present, before an item of equipment can be purchased it must be included by name and approved by the budget bureau of the Government. It is impossible to forsee all eventualities, and if an item is needed in the middle of an experiment it cannot be purchase legally. Provision for a contingency fund in the research budget would provide a means whereby emergency items and services could be secured.
There is a great deal of delay in obtaining actual cash for expenditures, such as those for field trips, even though the expenditure has been authorized. For example, the expert and his counterpart had to wait a month for money before they could go into the field. At times a biologist cannot do his authorized field work because he cannot get the money in time. He may go so far as to use his own funds to pay for the expenses of the field trip and then wait for weeks for reimbursement. However, this tends to strangle initiative and it is really expecting too much of the biologist.
Steps should be taken by the Department of Fisheries to correct this fault, wherever it lies, whether within the Department or some other department of the Government.
The flood plain fishery has been aptly described in FAO/UN (1965) which also indicates the studies being conducted of this fishery at Ayutthya. These studies were enlarged during 1964–1965 to include records of the daily catch for six traps at Nakorn Sawan and a detailed study of three traps at Ayutthya. At Ayutthya, records were kept of the daily catch, size and species composition, and ecological factors, and once a week samples were taken every four hours during a 24-hour period to determine differences in time of movement of different species. A great deal of life history information was also collected.
These data have not been analyzed completely because of the large amount of material collected and the departure of Mr. Snit from the Inland Fisheries Division. This work has progressed very well, but with the departure of Mr. Snit there is an urgent need to put someone in charge of this important project.
The catch records of the six traps at Nakorn Sawan are summarized in the following table.
The flood fishery usually extends from December through February. An individual trap generally operates from about two to three months.
| Trap | Area | Total catch | Catch in kg per unit area on basis of area at high water | ||||
| At low water | At high water | ||||||
| rai | (ha) | rai | (ha) | kg | per rai | (per ha) | |
| 1 | 120 | (19.2) | 3,000 | (480) | 70,621 | 23,5 | (147.1) |
| 2 | 280 | (44.8) | ? | ? | 69,743 | ? | ? |
| 3 | 15 | ( 2.4) | 1,000 | (160) | 28,337 | 28.3 | (176.8) |
| 4 | 258 | (41.2) | 2,500 | (400) | 24,612 | 9.8 | ( 61.2) |
| 5 | 37 | ( 5.9) | ? | ? | 82,528 | ? | ? |
| 6 | 80 | ( 12) | 2,500 | (400) | 53,684 | 21.4 | (133.7) |
| Total | 329,516 | ||||||
These six traps have resulted in a considerable harvest of fish, almost 330,000 kg, which is even more remarkable when we realize that the flooded land that produced it consisted of so-called “waste land” or forest and bush.
Similarly, the three traps that were surveyed at Ayutthya: Bang Wai, Kok Tong, and Pak Hai, resulted in a harvest of 132,484, 590,747, and 21,622 kg respectively, again during a period of about two to three months, a total of 744,854 kg of fish that were produced for the most part on flooded “waste land”.
What is the future of the flood plain fishery in Central Thailand? It does not look good; the flood plain fishery is probably doomed to near extinction because of man's activities.
The most important of these is the development of an irrigation system which will prevent the annual inundation of the flood plain. Its purpose is to grow two crops of rice annually.
Now, what is the comparative value of the two products, the extra crop of rice against the natural crop of fish? Possibly the fish are as valuable or even more valuable to the economy of Thailand than is the extra crop of rice, and it is, therefore, recommended that the flood plain fishery in Central Thailand be evaluated on a monetary basis.
This is to be done by determining:
the number and location of all traps,
the area during high water from which these traps harvest fish,
the annual harvest of selected traps throughout the central valley, and
by extrapolation the total harvest and monetary value of fish captured in the flood plain fishery.
Some of the flood plain habitat is associated with swamps close to large waterways. It is quite possible that a co-operative effort between the Fisheries and Irrigation Departments could result in these swamps being incorporated into the irrigation plans to serve “as reservoirs” during the flood season. Thus they would serve the purpose of water storage during flood period and as a source of harvestable fish as the water recedes.
If most of the central flood plain will fall under an irrigation plan, then it will be necessary to produce fish in conjunction with rice. Now is the time to plan for this; the experimental work in fish culture in rice fields that is being conducted at Chainart Fisheries Station should be accelerated.
Large main-stream reservoirs are new to Thailand - they are new to Southeast Asia - and the first of this type is Bhumipol Reservoir which was completed in 1964. Two more were completed in 1965, one on the Nam Pong and one on the Nam Pung. Through the efforts of the Mekong Committee, the Irrigation Department, and the National Energy Authority there will be soon an even greater number of reservoirs. Additional reservoirs are planned for the Pattani River near Yala, the Meklong near Kajchanaburi, a small stream east of Khon Kaen, and others on tributaries to the Mekong River.
There is literally no information on this type of reservoir in the tropics, and the Inland Fisheries Division of Thailand is sitting on a “scientific gold mine”. Happily, an effort has been made to work the mine.
The Division has a record of the catch landed at the dam for the last 18 months, and at the upper end of the lake for the last 6 months. The plan calls for extending the census to one other site.
Dr. Larimore suggested a wise course of study for Bhumipol Reservoir which this expert tried to implement; but because of a series of unusual circumstances the study was not carried out.
Five major studies need to be made:
a census of the harvest,
experimental fishing,
the life history and growth of the important fishes,
limnology
the reproductive success of important fishes.
In general the biologists of the Inland Fisheries Division have the knowledge needed to conduct these investigations that which they may lack can be obtained from the biologists in the Marine Investigations Division - all they need do is ask. However, under the present system of staffing each Inland Fisheries Stations, with only one biologist, this work cannot be done because it is impossible for one man to do it. At least three men are needed: two stationed at the reservoir, and one, who is in charge of reservoir research and will also conduct a part of these investigations, stationed in a laboratory at or near Bangkok.
The time expended to census the harvest might be reduced by establishing a stratified rather than a total census. This would allow the biologist to work at other projects. Dr. T. Yamamoto, FAO/EPTA Regional Fisheries Statistician stationed at the FAO Regional Office, Bangkok, would be helpful in the design of this census.
It is recommended that:
an intensified effort be made to accelerate the study of Bhumipol Reservoir along the five main fields of investigation listed above,
these be long-term studies (in the case of experimental netting this needs to be done monthly for at least a year),
the staff of biologists working on the reservoir be increased to three, and they be supplied with needed basic equipment, and
a stratified census of the harvest be started in order to save time for other investigations.
This reservoir became operational in June 1965. The project will be completed with the construction of the diversion dam down-stream from Pong Neeb Dam which will impound a small irrigation reservoir. Biologists of Inland Fisheries Division have conducted a pre-impoundment survey of the large reservoir.
A large deep reservoir such as this presents new problems of fishing to the local fishermen. Experimental netting needs to be conducted here to learn how and where to catch fish and what kind of gear is most suitable. This information needs to be extended to the local fishermen.
It is suggested that the course of study suggested for Bhumipol Reservoir be applied to this reservoir, and that the studies be made by biologists stationed at the Fisheries Station at Khon Kaen. This station could be made into a center of research for this region. It is suggested that aside from extension personnel four biologists be assigned to work out of Khon Kaen. One would be concerned with fish culture in ponds and rice fields, the second with fish management and research in swamps and irrigation tanks, and the other two biologists assigned to develop the fisheries on the new reservoir.
It would be well establish a sub-station at Pong Neeb Dam from which research and census work could be conducted.
It is recommended that:
the same studies that were suggested for Bhumipol Reservoir be made at Nam Pong Reservoir,
this work be conducted from the Fisheries Station at Khon Kaen and a sub-station be considered for Pong Neeb Dam, and
the number of biologists at Khon Kaen be increased to four.
Many other reservoirs will be constructed on rivers in Thailand. Every time a new reservoir is constructed a program of study similar to that outlined for Bhumipol Reservoir could be initiated. Since this could be a never ending procession of studies, the expert suggests that complete and continuing studies be conducted on perhaps only three or four new reservoirs: Bhumipol, Nam Pung Reservoir, the projected one on the Meklong, and perhaps the one to be built on the Pattani River at Yala. The information derived from these can probably be applied to similar new reservoirs.
It is recommended that: an effort be made to conduct complete continuing studies on selected reservoirs and the findings applied to future reservoirs.
FAO/UN (1965) contains a thorough discussion of other types of aquatic habitats in Thailand: small and large swamps, irrigation tanks, rice fields, and fish ponds. The present expert is in agreement with the recommendations of the report and sees no need for further discussions of the subject here.
The problem of gathering fishery statistics is especially complex in Thailand, yet their collection is vital if the importance of inland fisheries is to be recognized. Dr. Larimore suggested a number of sources from which these statistics can be gathered and initiated a survey of markets in the Northeast.
In the Inland Fisheries Division there is no one who understands the importance of this work nor is there anyone assigned specifically to it.
The data from the survey of the markets in the Northeast are filed away without analysis.
The expert has discussed the matter of inland fisheries statistics with Dr. Yamamoto who was keenly interested in the problem.
It is recommended that: (i) a biologist with good fisheries statistical training or a fisheries statistician with a knowledge of inland fisheries be appointed to work on a full-time basis on the development of a statistical system for inland fisheries. In developing such a system the staff member should consult the FAO/EPTA Regional Fisheries Statistician, Dr. Yamamoto.
The expert saw most of the Fisheries Stations in Thailand and was very impressed with them. The stations are well kept, have good facilities for the production of fry, and most of them have extra ponds, of concrete or soil, that can be used for research projects.
Each station has an office-laboratory building and a variety of equipment for research. Some of the equipment is for highly specialized work, it could be termed “fancy” equipment, and some of the basic fisheries equipment is lacking or in poor condition. Much of the basic equipment wears out rapidly and should be replaced occasionally. The purchase of equipment should be determined by the nature of the research projects, and the biologists should request only that equipment which is needed. They must learn to improvise and be encouraged to do so.
Where applicable, the following basic equipment should be at each station: good measuring boards, gram scales, kilogram scales, one-quarter inch mesh minnow seines, mechanical or electrical calculators, limnological-chemistry kits, pH colorimeters, nets (gill nets, hoop nets, traps), etc. It is strongly suggested that 16-foot outboard-motor boats be secured to replace the inadequate long-tail boats which are unsafe to use especially in open waters such as reservoirs.
The Inland Fisheries Division now has 14 freshwater fisheries stations and 2 brackishwater fisheries stations. With the construction of dams throughout Thailand there appears to be a desire to construct a fisheries station at each dam to raise fry to stock the new reservoirs. This is not necessary, and will lead to a proliferation of stations that will not be adequately staffed or equipped to conduct needed investigations. If fry are needed to supply fish culturists, such as those southeast of Bangkok who raise Clarias, private individuals should be encouraged to take up this line of work.
The expert suggests that there is no need for more fishery stations in Thailand, with two exceptions.
A dam for irrigation and power is to be constructed on the Pattani River near Yala. A fisheries station and hatchery could be constructed here if needed, and the Patalung Station could be closed. This subject has been fully discussed in Special Report No. 1, submitted by the expert to the Government.
The expert is opposed to the establishment of a station and hatchery at the site of each new dam and reservoir. However, it may be well to construct sub-stations at some of these. A sub-station could consist of a small structure that would serve as a combination laboratory, storage, and office building for census personnel. A small building to supply living quarters could also be provided for biologists who would come periodically from Bangkok or nearby regular stations to conduct research projects.
The investigations that can be conducted at the brackishwater stations are closely allied to marine investigations.
The Fisheries Department may want to consider turning these stations over to the Marine Investigations Division or the two Divisions could operate the stations jointly.
It is recommended that:
certain basic equipment be supplied each fisheries station;
there is no need for more Inland Fisheries Stations with the exception of one near Yala, at some future time, and sub-stations on some of the new reservoirs;
the Department of Fisheries consider turning the Brackishwater Fisheries Stations over to the Marine Investigations Division or the two Divisions operate the stations jointly.
The expert was impressed with the extension program in only one station he visited; this was Nong Harn located in the critical region of the Northeast. The Station Chief, Mr. Duang Techakomol, is doing an excellent job in taking the knowledge of fish culture to the farmers within his region.
At other stations, the biggest problem with respect to the extension program seems to be lack of activity on the part of their station chiefs. That is, they appear to sit and wait for the farmer to come to them for help. It should be realized that the farmer who needs help may be located, say 50 kilometers from the station and does not have the means to travel to the station for help.
The biologists and station chiefs in the Inland Fisheries Division have a basic knowledge of fish culture in ponds and rice fields, pig-aquatic weed - fish extension culture etc. Furthermore, Dr. S.W. Ling provided a sound basis for extension work over 10 years ago and many of the present station chiefs were taught by him. However, despite this knowledge, the station chiefs and personnel are not going to the farmers and inducing them to raise fish. Extension personnel should not sit in their offices and wait for the farmers to come to them for help, but go to the farmers and induce them, show them, and work with them to manage their ponds in multi-purpose ways.
It is specifically recommended that:
extension personnel begin an active program by:
going into their districts, contacting village chiefs and farmers and selling them on the idea of fish culture;
helping them get started whether it be by digging a new fish pond, removing weeds from existing ponds, killing off old fish populations, or improving small swamps (a part of the present program, and a good one);
encouraging multiple use of a pond, i.e., the culture of fish, raising of pigs over a pond, and feeding aquatic vegetation to the pigs;
providing free fish to farmers for initial stocking of their ponds;
re-visiting each farmer periodically to see how his project is progressing and continuing this until he no longer needs help;
this active extension program be started immediately in northeastern Thailand where the need is greatest;
in the Northeast a survey be made of existing natural bodies of water in conjunction with the Irrigation Department and a plan be made and implemented for their improvement, taking into consideration fish production, domestic water supply, and irrigation;
the people of the Northeast be warned of the danger of becoming infected with liver fluke by eating raw or improperly cooked fish.
The fishery laws of Thailand make it illegal for anyone to use electro-fishing gear and poisons to capture fish. Thus the biologists are prevented from using these methods in research and management projects, even though these methods are used throughout the world by many scientific fishery organizations. On the other hand this law does not really prevent the use of these methods by unscrupulous fishermen. They find it profitable to do so because the fishery laws are not adequately enforced.
In 1963–1964, Dr. Larimore estimated that 50 electro-shockers were being operated illegally in Bung Borapet. A year later, the present expert, with the help of the station biologist, estimated that 200 shockers were being operated illegally in or near the swamp, along with poisons (insecticides), illegal nets, and illegal fishing within the sanctuary.
It was determined that with one shocker it is possible to catch about 300 kg of fishes per night, valued at 1200 baht (US$60.00). This is profitable to the fishermen but detrimental to the stocks of fish. The use of this illegal gear is spreading in Thailand, and will continue to do so unless checked by rigorous law enforcement. (This serious problem has been discussed in detail by the expert in Special Report No. 2 which was also presented to the Government).
It is recommended that: the biologists should be allowed to use electro-fishing gear and poison (rotenone) in the legal discharge of their duties, such as making fishery surveys or studying life histories and in the management of irrigation tanks.
The electro-fishing gear used on Bung Borapet is an efficient method to capture pla chon (Ophiocephalus), a highly prized carnivorous fish. It occurs in many irrigation tanks and apparently prevents stocked Tilapia from establishing a population in many tanks. Selective fishing, only for Ophiocephalus, under rigid control by the Inland Fisheries Division, may allow stocked fishes like Tilapia and Trichogaster to become an important part in the production of irrigation tanks. Also, by curtailing the numbers of this predator, the numerous herbivorous fishes could grow and add to the production of the tanks.
An experiment, over a two-year period, may indicate the effectivness of the electric shocker in controlling Ophiocephalus.
First year.
Select a moderate sized irrigation tank near Korat.
Determine the species composition, weights, and lengths, of all species by seining and partial poisoning techniques.
Determine the size of the Ophiocephalus population.
Use the shocker to capture Ophiocephalus.
Mark, by cutting off a fin, and release.
Repeat a and b, and estimate size of population. 1
Stock Tilapia and Trichogaster.
Seine each month to determine the abundance and growth rate of stocked fish.
At the end of 12 months estimate the population of Ophiocephalus again.
Second year.
Remove Ophiocephalus by repeated shocking.
Stock Tilapia and Trichogaster.
Each month continue to remove Ophiocephalus by stocking.
Determine abundance and growth rate of stocked fish as in “5” above.
At the end of experiment, seine and poison the tank to determine the species composition and the weights and lengths of all species.
1 For details of this method, see Lagler (1956), p. 167.
During the dry season of about 6 months, large numbers of Macrobrachium rosenbergii move up the Chao Phya to be stopped by the dam at Chainart.
The prawns attempt to crawl up and over the locks and it is here that the biologists pick them off and transport them upstream. The expert thinks that this may be a waste of time and that if the lock were flooded early in the morning when it contains a maximum number of prawns and the upper gate were opened the prawns would pass above the dam. This could be verified by a simple marking and recovery experiment done in co-operation with the authorities that operate the dam.
The prawns exhibit a remarkable ability to climb and will climb 20 feet up the side of a vertical concrete wall if a trickle of water is present. This suggests that a “ladder” may be devised to allow the prawn to crawl over the dam. The expert suggested a number of designs for a “ladder”. Through trial and error some effective device may be found.
Young prawns can be collected in several ways at the dam and in the river. The prawns can also be cultured in ponds and will grow rapidly to marketable size, as has been shown by Dr. Ling. It is quite possible that the prawn can be effectively cultured commercially in ponds and in rice fields. Since Chainart is the head of an irrigation system it would be well to continue experiments along this line at the excellent new Fisheries Station located here. Such experiments were started in 1965.
Dr. Ling, who is now based at Bangkok as FAO/EPTA Regional Fish Culturist, is willing to discuss informally any aspect of the culture of the giant prawn when he is not on assignment. Dr. Ling's services should be solicited by biologists in the Department, especially by Mr. Boonchuay Chaopaknam, who is working on this project.
It is recommended that:
the gates of the lock at Chainart Dam be manipulated experimentally to see if the prawns will move through them so as to re-populate the river above the dam;
experiments be made to devise a “prawn ladder” which will allow prawns to move over dams;
the experiments on prawn culture in ponds be continued until a successful method of culture is devised;
experiments in prawn culture in rice fields be started;
Dr. Ling be consulted about this work.
Two general types of aquatic weeds need control in Thailand: floating weeds and submerged rooted ones. Three methods of control may be used: chemical, mechanical, and biological. In all probability the weeds will never be eliminated but only controlled, hence this will be a never ending operation.
The control of water hyacinth (Eichhornia crassipes) is the main problem in Bhumipol Reservoir and Bung Borapet Swamp. In the reservoir it has become so thick and compacted that it interferes with navigation. Mechanical devices, regardless of size and method of operation, are useless in the control of water hyacinth in large bodies of water and are no longer used in most countries where this weed is a problem. Control of water hyacinth is best accomplished by use of the chemical 2–4 D. The application of 2–4 D is best done by small craft, 16-foot boats, equipped with motor-driven pressure sprayers and outboard motors. Where there is a large mass of water hyacinth, aerial spraying can be the initial operation, followed by maintenance spraying from small boats.
The chemicals, Diquat and Paraquat, can be used for both water hyacinth and Salvinia. They are more costly than 2–4 D, however, they are 100 percent effective and may therefore be worth the added cost.
Water hyacinth has formed large impenetrable mats in certain areas on Bhumipol Reservoir. Control could best be accomplished by an initial aearial application of 2–4 D and after 72 hours the spots that were missed should be sprayed from small boats. After 6 weeks, the remaining mats should be sprayed again from small craft. Further maintenance control can be done from craft small enough to enter the little coves and tributaries where water hyacinth may be present.
It is obvious that this problem can best be attacked on a co-operative basis with the Department of Fisheries, Irrigation Department and the Power Resources Agency.
It is recommended that:
the weed problem in Bhumipol Reservoir be attacked through a co-operative effort of the three agencies listed above;
control be accomplished by the application of 2–4 D as outlined above, and that
one of the agencies involved be charged with continued maintenance control of weeds on the reservoir.
This large swamp, and others like it, also contains excessive amounts of water hyacinth that can be controlled by the use of 2–4 D applied from small boats. Since the water level in this swamp can be controlled, it is also possible to lower the water level, trap the weeds on land to let them dry out, and then spray the remaining weeds.
It is recommended that:
the control of water hyacinth on Bung Borapet Swamp be accomplished by spraying with 2–4 D from small craft.
Submerged rooted aquatic weeds are a problem in some large swamps and lakes, as in Kwan Payao. Their control by chemicals is costly, difficult and can be lethal to fish. With this type of weed, biological control is a distinct possibility. If fish can be found that will eat the weeds, the weeds will be controlled and converted into a source of protein for human consumption. The Chinese carp, Ctenopharyngodon idellus, will control submerged aquatic weeds.
The biologist at Kwan Payao is now experimenting on the control of weeds by herbivorous fishes using both indigenous species and the Chinese carp. This work should be continued and when Mr. Suchit returns to Thailand he should try to breed the Chinese carp, by the use of pituitary injection, so as to provide a supply of this fish to be used in weed control.
It is recommended that:
the control of submerged rooted aquatic weeds be accomplished by biological controls, and
induced spawning of Chinese carp be developed to supply fish for weed control.
Irrigation tanks, relatively small bodies of water, may pose acute weed problems. For example, an irrigation tank near Udorn with an area of 7,600 rai (1,216 hectares), is almost completely covered with a mat of Salvinia thick enough to support the weight of a dog. The area of open water is only 5–6 rai (one hectare) and the depth is about one meter. In 1963–64 the tank was stocked with 8,000 Tilapia and Trichogaster fry. It is doubtful that this stocking could have resulted in a measurable addition of fish to the local people. The tank is supposed to be managed by both the Fisheries Department and Irrigation Department. At the time the expert saw it, the tank was nearly useless for fish production and soon would lose its water storage capacity and become useless for irrigation.
Salvinia can be controlled chemically (using Diquat and Paraquat). It can also be killed readily by drying, as the expert's counterpart has pointed out. He suggested that it would be a simple matter to draw down the irrigation tank just prior to the monsoon, and hold the low level long enough to effectively dry and kill the plant. With reflooding, remaining patches of the weed could be sprayed or removed mechanically. The expert thinks this is an excellent idea and should be tried.
If the tank is not completely dried, a stock of fish will remain to repopulate the tank. However, even if all the fish were killed, this would be no great loss; the tank could easily be stocked with a desirable species combination.
Clearly, this type of management should be a co-operative effort between the Department of Fisheries and the Irrigation Department.
It is recommended that:
the Fisheries and Irrigation Departments co-operate on a weed control program in irrigation tanks;
the control of Salvinia in tanks be attempted by draining, drying the weed, and removing it mechanically after reflooding.
Small ponds and swamps are sometimes completely covered by water hyacinth and are thus useless for fish production. In small bodies of water mechanical removal of the weed can be done easily. Not only is the water hyacinth easily removed, but it can be chopped, mixed with rice bran, and fed to pigs. This will allow better fish production in the body of water, and a continued supply of food for pigs, resulting in another desirable protein-rich food supply. Dung from the pigs can be used to fertilize the water to increase its productivity. Dr. Ling recommended this management practice more than 10 years ago, but apparently little attention has been paid to his recommendations.
It is recommended that:
extension personnel and the Station Chiefs at the Inland Fisheries Stations be charged with the management of small bodies of water as mentioned above.
One of the major functions of the Fisheries Stations is to raise and provide fry for stocking purposes. Four species are commonly raised: common carp (Cyprinus carpio), giant gouramy (Osphronemus goramy), kissing gouramy (Helostoma temmincki) and Tilapia. Fry are sold to farmers who stock them in their ponds and remaining fry are stocked in swamps and irrigation tanks.
During one year at Udorn, 206,177 fry were produced. Of these, 67,547 fry were stocked in new and old ponds, 67,100 in natural swamps, 15,600 in improved swamps (ones where a dam has been constructed to raise and maintain the water), and 55,930 in irrigation tanks. After assuming a 50 percent mortality and taking into consideration the expected growth for one year, it was estimated that stocking produced 12,886 kg of fish valued at Baht 77,602 (US$3,865). (These figures are based on a summary put out by the fisheries station and with minor corrections made by the expert).
Dr. Larimore initiated projects, which have been continued, to evaluate stocking of tilapia in natural waters. It appears that tilapia do not survive an appreciable time after the initial stocking. The reason for this is not known, but it is possible that they may be removed by predators, perhaps Ophiocephalus (see Section 3.81 on Electro-fishing and the Use of Poisons for a detailed experiment designed to determine the part predation may play in the failure of tilapia to survive).
This indicates that it may be well to re-examine the stocking policy. If the species complex in a swamp is not known and there may be a large number of predators in it, and if the predators are effectively removing the stocked tilapia, then one can not assume a 50 percent mortality and a certain figure for production. It may well be that no appreciable number of fish are produced through stocking.
Of the fish produced in the station at Udorn, 70 percent of them are stocked in swamps or irrigation tanks and into an unknown species complex. Except for the carp and tilapia this could be called indiscriminate stocking. This type of stocking is of little or no value, especially when a species is stocked that naturally occurs in a body of water unless that body of water is subject to severe overfishing. As an example, it would be of no value to stock a fish as Probarbus jullieni after it were determined that it can live and reproduce in reservoirs.
It is recommended that:
the role of tilapia stocked in swamps and irrigation tanks continue to be evaluated,
the experiment detailed under section 3.81 Electro-fishing and Use of Poisons, be carried out,
the species complex in a body of water be determined before any thought is given to stocking that body of water,
indiscriminate stocking be stopped,
a study be made of the possibility of stocking some of the rapidly growing fine food fishes such as Probarbus jullieni and Pangasius spp.,
a greater proportion of the fish produced in the Fisheries Stations be stocked in ponds and rice fields and that they be managed to produce fish.
The School of Fisheries at Kasetsart University now has a functioning museum established by Dr. Karl F. Lagler under the United States AID Program. The Inland Fisheries Division, as it continues to enlarge the scope of its fisheries survey work will collect fishes from all parts of Thailand. These specimens will be invaluable to scientists of Thailand and abroad.
It is recommended that: the Inland Fisheries Division and the School of Fisheries co-operate in the systematic collection of fishes and their deposition at the latter's museum.
The scientific attitude demands that a biologist should be concerned only with facts, regardless of how these facts may alter or vary from present ideas. The biologist should not consider a problem lightly. He must plan his approach to each problem very carefully and after due consideration of all possible factors that may affect it. He must be able to modify, improvise, and alter his plans if early results so indicate, and not follow blindly a research outline. Whenever possible, controls should be established, from which he can evaluate his experimental results.
Neither the research biologist, nor -especially- the administrator, should expect every experiment to succeed; many may fail, but the biologist, if vitally interested in his work, will learn from those that fail as well as from those that succeed.
Accurate work is absolutely essential in scientific research. In order to obtain accuracy the biologist must first see the need for accuracy, constantly check his calculations and results, and actually do the work himself. The expert has noticed a distinct tendency of many fishery biologists in Thailand to let the laborers or clerks do much of the work they should do. This only leads to serious errors because the laborers and clerks have little interest in the basic problem. The laborers and clerks work by the clock; the true research biologist must work longer hours than they, that is, on his time at night.
It appears that when a biologist has a college degree he often sits himself apart, upon a high plane, and is reluctant to do certain chores such as setting nets, and tabulating his own data. This is a poor attitude to take and leads to poor results. The expert has observed, on a number of occasions, that tabulation and analysis of data are given to clerks to do. The expert has examined some of these data and found many of them to be in error. Apparently the biologist assumes that the clerk will do his job for him and do it accurately, therefore he does not bother to check the results critically. In one case the expert checked some of the results of the inland fisheries investigations and found an error in the recorded harvest in excess of 250,000 kilograms, or more than one-third of the total harvest. This is no little error.
There is no place in scientific work for the attitude symbolized by the phrase mai pen rai (“it doesn't matter”).
What recommendation from the expert will correct this problem? He can only say that the biologist must be shown that he has a tremendous responsibility, that of providing food for his people. The change has to come from within him. If he does not change he should be dismissed from his responsible position.
When the expert began to work with his first counterpart, who is an excellent biologist, he was surprised to find that his counterpart had no knowledge of the activities at the other stations. The expert was soon to find out that in general there is a lack of communication and exchange of information within all levels of the Department of Fisheries. The station biologists work in intellectual isolation, and do not know of the work of one another even though they are working on the same type of project. The Senior Biologists do not discuss their work with one another even though they are housed in the same room. As far as the expert knows, the Chief of Inland Fisheries does not communicate the problems of the Division or Department in a general meeting with his Senior Biologists. There apparently is little communication or co-operation between the Division and closely related agencies, such as Irrigation, Rice, Public Health, National Energy Authority (hydro-electric projects), and the Committee for the Co-ordination of Investigations in the Lower Mekong Basin.
It is recommended that greater liaison be established between the above mentioned groups. Only when projects and problems are discussed with others can we see the common ground we walk on, and that we can be of mutual assistance. It is suggested that the following activities may well accomplish this.
A quarterly and annual report of research and station activities should be started. The progress of the projects would be set forth briefly each quarter and sent into headquarters on time. These reports could be mimeographed and sent to all personnel. An annual report could be handled in the same way.
If a research group of biologists were established that would go out to work at the stations, this would be helpful. A research group bound together and vitally interested in their research would soon begin discussing this work, which would lead to seminars. Monthly staff meetings, and frank discussions between the Administrators and Senior Biologists, would be helpful for both groups. This would lead to better understanding of all problems and a more rational solution of common problems.
The dissemination of knowledge occurs via the spoken word and written word. The “First Guide to the Literature of the Aquatic Sciences and Fisheries in Bangkok, Thailand” (Kasetsart University Fishery Research Bulletin No. 2) pointed out the literature that is available and unavailable in Bangkok. Pertinent literature in fisheries is needed, as well as time for the biologist to use the library for research and study, if the Division is to develop. The station biologists do not have access to library facilities, and for all practical purposes neither do the biologists in Bangkok. They rarely use the Department's library.
It is recommended that:
A part of the budget be set aside for the yearly acquisition of the important literature in fisheries,
the biologists be encouraged and allowed to use the libraries,
when station biologists undertake a research project, they make a complete search for pertinent literature in the libraries in Bangkok (Department, Kasetsart University, Chulalongkorn University, and the FAO Regional Office),
the libraries in the above mentioned organizations coordinate the acquisitions of their new books and journals, so duplications will be avoided and they can realize the maximum number of new books for the minimum of money.
Liaison with other agencies should be established because of the benefit to the Department, specifically, and to all concerned in general. This liaison needs to be at the level of the administrators and the working biologists. Some examples of the need follow. The problem of water hyacinth in Bhumipol Reservoir is a problem for the Department of Fisheries as well as for the Irrigation and the National Energy Authority; the problem of the human liver fluke in the Northeast is a problem for the Department of Fisheries, Public Health, and the Institute of Tropical Diseases; and the Department of Fisheries, Rice Department, and Irrigation Department should all be interested in the culture of fish in rice fields.
The expert found that although the responsibilities of different Departments may overlap, they do not seem to co-operate with one another, hence little is done. For example, both the Irrigation Department and Department of Fisheries are concerned with weed control in irrigation tanks. Yet, there are no biologists in the Irrigation Department with a knowledge of weed control and they do not contact the Department of Fisheries where the biologists do know how to control weeds.
The Irrigation Department makes fishing regulations for irrigation structures but they are not based on biological information, and, it is judged, without consulting the fisheries people. As an example, they regulate fishing in irrigation tanks and prevent fishing in irrigation canals. Clearly, the promulgation of fishing regulations is the function of the Department of Fisheries. Fishing is prevented in irrigation canals because, as the expert was told, the fishermen would destroy the bunds by walking on them, but the bunds are being destroyed, not by fishermen but by water buffalo coming down the bank to bathe).
Irrigation tanks are stocked with fish by the Irrigation Department. When the expert inquired as to the stocking practice he was told that they buy some fish, such as Clarias, from a local market and dump them into the tank. There is no justification for this costly and wasteful practice. Proper stocking and management is the function of the Department of Fisheries.
If the Department of Fisheries wishes to conduct a survey or manage an irrigation tank to increase fish production they must first obtain permission from the Irrigation Department, which is a time consuming process.
The Department of Fisheries should be given authority on all aquatic resources (waters) when it comes to the management of these resources for the production of fish. This includes weed control, stocking procedures, fishing regulations, etc.
But, there should be close co-operation between these two departments to expedite certain fish management practices which appear to run counter to the interests of irrigation. As an example, one way to manage an irrigation tank for fish production is to remove the native species complex and restock it with a more desirable combination. This can best be done by draining the irrigation tank. At first thought this appears to be counter to the purpose of the irrigation system, but complete drainage can be done just prior to the monsoon, the fish population destroyed, and the tank filled as the rains begin.
There is also need for liaison between these two departments so that the Department of Fisheries knows where and when a tank will be completed so that it can plan to manage the tank for fish production.
The Department of Fisheries may wish to suggest modifications in control structures (spill-ways, gates, etc.) so as to make the management of the tank easier. For instance, some tanks cannot be drained completely through the water level control gate because the gate is at a higher elevation than the bottom of the tank or swamp. It would be a simple procedure during the construction of a tank to dig a channel from the bottom of the tank to the gate, and place the gate at a low enough level to ensure drainage.
During periods of heavy run-off, unwanted fishes may swim up the spill-way and actually jump into the tank to reproduce and prey on a desirable complex of fishes. With a co-operative effort a fish screen could be built into the spill-way to prevent this.
It is recommended that:
the Department of Fisheries be given control of aquatic weed eradication, fishing regulations, stocking policy, and the management for fish production of all public waters in Thailand, and
the Department of Fisheries and Irrigation Department cooperate very closely in the design, construction, operation and management of existing and future irrigation tanks.
Just prior to the departure of the expert, an attempt was made by interested individuals in the Department of Fisheries, Kasetsart University, AID, and FAO, to establish a society for furthering the knowledge of aquatic sciences in Thailand. The society was given the provisional name of “The Association of Aquatic Scientists of Thailand” (A.A.S.T.).
A functioning society would be an invaluable aid to the development of fisheries in Thailand. At the meetings, especially during the course of informal talks, mutual problems could be discussed and joint efforts made to propose solutions. The meetings could also serve to exchange information between the Department of Fisheries and other departments. The biologists could receive training by formally presenting the results of their work at the meetings, their work would be discussed, and they would receive valuable suggestions for furthering their researches.
The expert believes that the greatest benefit of A.A.S.T. to the Inland Fisheries Division would be in the exchange of information and especially the free discussion of the results of research projects. With a functioning society, the Station Biologists, for one, would no longer be in the state of intellectual isolation they must now endure.
It is suggested that the scientific aspects of the society be pursued vigorously and that minor attention be placed on the typically social aspects.
It is recommended that:
all members of the Department of Fisheries especially those in the Inland Fisheries Division, cooperate in every way possible and take on the personal responsibility to see that the society becomes organized and functional,
each Station Chief and Station Biologist be encouraged to participate in the activities of the society and that they be given the opportunity to do so. It would be especially desirable for them to attend the annual meeting and be encouraged to present the results of their research at this time.
4.1 Review and Revision of Technical Projects
The expert reviewed the current projects and where needed made suggestions for improvement.
4.2 Program for 1965
Following the above review, a program for 1965 was developed, put into effect, and work carried out in the field and laboratory. Training was given counterpart personnel and other field officers in the development, conduct and evaluation of the field program.
4.3 Administrative Arrangements
The expert was asked to help draw up a plan for the reorganization of the Department of Fisheries. Comments were submitted to the Director-General of the Department, as were comments on budgetary matters.
The flood plain fishery in Central Thailand should be evaluated on a monetary basis (see Section 3.41).
A long-term and intensive study should be made of Bhumipol Reservoir (see 3.421).
Similar studies should be made at Nam Pong Reservoir (see 3.422), and a few other selected reservoirs. (see 3.423).
An inland fishery statistics program should be developed (see 3.5).
Certain basic equipment should be supplied each Inland Fisheries Station (see 3.6).
No new inland stations need be created at this time, but in the future one station near Yala might be opened, and it may be convenient to have sub-stations on some of the new reservoirs (see 3.6).
Consideration may be given to turning the Brackishwater Fisheries Stations over to the Marine Investigations Division or having the two Divisions operate them jointly (see 3.6).
A really active extension service program should be undertaken following the specific recommendations in section 3.7.
Biologists should be permitted to use electro-fishing and other methods of sampling currently forbidden by law (see 3.81).
Experiments should be conducted to facilitate the movements of the giant freshwater prawn over barriers (see 3.82).
Experiments on the culture of the giant prawn should be made (see 3.82).
Aquatic weed control measures should be worked out, especially at Bhumipol Reservoir and Bung Borapet Swamp, and in selected irrigation tanks and ponds following the recommendations in section 3.83.
The fish stocking policy should be evaluated, indiscriminate stocking stopped, and a greater portion of the fish produced in the stations used to stock rice fields and ponds where they can be managed (see 3.84).
The Inland Fisheries Division should collaborate with the School of Fisheries, Kasetsart University, in making systematic collections of fish (see 3.85).
The fishery biologist should adopt a completely scientific approach, collect, tabulate and analyze his own data, learn to improvise and never follow a predetermined course blindly - in full recognition that he holds a position of responsibility in the production of food for Thailand (see 3.86).
Important fisheries literature should be acquired, the several libraries concerned should coordinate their efforts in this field, and the biologists should be given every chance to use the libraries (see 3.87).
The various Departments of the Thai Government should co-operate closely where their fields overlap. This is especially true for the Departments of Fisheries and Irrigation (see 3.88).
The fisheries officers should be encouraged to join the Association of Aquatic Scientists of Thailand and to participate in its activities (see 3.89).
FAO. 1949 Fisheries Mission to Thailand, Report of the FAO Fisheries Mission to Thailand. Washington, 73 p.
FAO/UN, 1965 Report to the Government of Thailand on the development of programs of inland fishery investigation, management and training. Based on the work of R.W. Larimore, FAO/EPTA Inland Fisheries Biologist Rep. FAO/EPTA, (2020):ii+36 p.
Lagler, K.F., 1956 Freshwater fishery biology. 2nd ed., Dubuque, Iowa. Wm.C. Brown, xii+421 p.
Ling, S.W., 1957 Report to the Government of Thailand on the development of inland fisheries. Rep. FAO/EPTA, (653):ii+50 p.
