Previous Page Table of Contents Next Page


In the sea fisheries of the Indo-Pacific region, over 2 million vessels now catch some 30 million tons of fish each year 1. This gives a rough average of 15 tons of fish per vessel per year. The greater part of this fleet is composed of small open canoes, most of which have no form of mechanization. Many of the small canoes land less than 5 tons of fish in a year. But together that great fleet of assorted craft supports over 5 million fishermen and their families. How will this vast fishing fleet develop over the next ten or twenty years?

There are a number of factors that must be noted before we can attempt to draft guidelines for modifications in fleet size and vessel design. These factors relate to fish stocks, manpower and fuel. They should be studied along with the economics, productivity and capital costs involved. Careful consideration of each of these will caution us against further imitation of the fleet development in industrial fishery countries of the temperate water zone.

1 Ref. FAO Country Fishery Profiles, and IPFC Country Statements.

4.1 Relative Factors

4.1.1 Fish stocks

Two major problems relating to harvesting fish stocks are:

  1. Over-pressure on major species such as shrimp and tuna, and

  2. Insufficient harvesting of under-utilized species such as squid and shark.

Examination of these problems would tend to favour future development of small rather than large vessels. The heavy fishing pressure to which the tunas and shrimp have been subjected has been caused mainly by large vessels. Tuna purse seiners of over 200 tons and 1,000 hp are now common in the Philippines, and double rigged freezer shrimp trawlers of over 100 tons and 500 hp are common in Indonesia. The vessels of the Malacca Strait fishery are smaller, mostly around 30 tons 100 hp, but what they lack in size they make up for in numbers. All of the boats mentioned are in the top 10 per cent in size of the total Indo-Pacific fleet of over 2 million vessels. To fish effectively for under-utilized species one generally needs a multi-purpose vessel since changes in gear used and species caught will be necessary during the different seasons when such fish are plentiful or available. Small vessels make much better multi-purpose units than large vessels. Small craft are also much less likely to over-exploit fish stocks since they lack the powerful gear and sophisticated instruments used in high pressure fishing.

A third factor relating to vessel size is the exploitation of the new 200-mile exclusive economic zones or EEZ. While in some cases, this may necessitate construction of larger craft, in most cases, it will not. If one doubts this, he should consider the case of countries like Britain which are rapidly scrapping their large distant water vessels and replacing them with boats of one quarter their size in tonnage and horsepower. Following the loss of fishing grounds now within the EEZs of other countries, many deep sea vessels were forced to fish within 200 miles of the United Kingdom. There they were outfished so clearly by "inshore" vessels in the 12–26 meters category that their owners soon withdrew them from service 1. Another factor to be considered is that countries with narrow continental shelves such as Indonesia and the Philippines have little prospect of any new commercial fisheries more than 50 miles from land. Some states with continental shelves of considerable width, such as Thailand, already find themselves with an over-capacity in large vessels due to the closure of grounds now in the domain of neighbouring states.

1 Ref.: Newspaper reports: Fishing News and National Press, U.K. 1978–79.

4.1.2 Manpower

The manpower question is a socio-economic one. Over five million men in the Indo-Pacific region depend on fishing as their chief or sole source of livelihood. In most of their communities, there is little prospect of alternative work of any kind for them or their families. To what extent are we justified in displacing them by introducing large vessels which can catch 10 times, or even 100 times as much fish as a traditional boat, with only 10 or 20 crewmen? One thing should be made perfectly clear. We do not need the large vessels to maintain production. Except in a very few cases such as longlining for tuna and fishing near uninhabited islands, the total harvestable yield within the EEZs could be taken by small boats. Many so-called "deep sea" trawlers and purse seiners in the Indo-Pacific are operating within three miles of the beach. They are competing directly with local fishermen.

Relating vessel design to manpower and employment requirements, we should consider (a) the capital cost per crewman, and (b) the fish production per crewman. Taking the latter first, suppose a country with 0.25 million fishermen produces 1.5 million tons of fish (a rough regional average). The average catch is 6 tons per man per year. In many areas, the average is actually much less. But using those figures, we could quite easily improve efficiency and double the production per man or even increase it tenfold. In some northern countries, the annual production per fisherman is over 100 tons. But what would we have achieved? Some 50 per cent or 10 per cent of the fishermen would be much better off, and the rest would be destitute. If there were ample attractive employment opportunities for them elsewhere, it might make sense, but when in most cases there is no alternative work whatsoever, it would be sheer madness or wickedness to displace them.

The capital cost of each fishing boat, per fisherman also requires consideration. In Europe, Scandinavia and North America, the vessel cost per crewman employed ranges from $10,000 for small open boats and half-deckers to over $100,000 for deep sea trawlers and purse seiners. The bulk of the modern boats in the 40–120 ton class cost from $50,000 to $80,000 per crewman. Now, when the credit limit of most small scale fishermen in the tropics is around $1,000 to $5,000, how can we possibly contemplate the more expensive craft? The only possible reason would be that the capital intensive unit can capture fish that the cheaper boat is unable to take. But in how many cases is that true? With modern methods of small boat fishing, such as squid jig, trolling line, pair trawl, pair seine, deep trap, and aimed gill netting, there are very few fish stocks that cannot be harvested by relatively low-cost vessels.

4.1.3 Fuel consumption

Given the current and growing problem of fuel supplies, we would be wise to consider vessel efficiency in terms of fish produced per fuel consumed. The Norwegian study referred to earlier indicated that offshore trawlers consumed 260 per cent more fuel than offshore longliners, for each ton of fish caught. Coastal gill net and line boats required only one-fifth as much fuel as the trawlers, to catch one ton of fish. Therefore, if we wish to reduce fuel consumption, we should encourage the use of vessels and gears that are less energy expensive. More power does not necessarily mean more fish.

The following table lists the 1979 earnings by top fishing vessels in Britain in the over 30-meter and under 30-meter categories. The last column, “earning per hp installed”, gives an indication of the energy cost of each. All of the seven best small vessels are less energy expensive, and the 240 hp pair trawler is six times more productive, than the largest stern trawler for each ton of fuel used. The figures might be somewhat unfair to the deep sea vessels since at that time, they were suffering the loss of Icelandic and Canadian grounds. But it underscores the viability of smaller vessels for fishing within the 200-mile EEZs.

Table 6. Fishing vessel earnings/fuel consumption statistics of top fishing vessels in U.K., 19781.
Vessel TypePortMain Engine (H.P.)Grossing at $2=₤1Earnings per HP Installed
(a) Vessels over 300 meters    
Deep sea trawlerHull1,950$980,000$ 503
Deep sea trawlerAberdeen1,700890,000524
Deep sea trawlerGrimsby700850,0001,214
Deep sea trawlerLowestoft1,650760,000460
Deep sea trawlerGrimsby1,400750,000536
Deep sea trawlerFleetwood1,900750,000395
Deep sea trawlerNorth
(b) Vessels under 30 meters    
Scottish seinerAberdeen560960,0001,714
Pair trawlerGrimsby240750,0003,125
Scottish seinerPeterhead420630,0001,500
Light trawlerEyemouth230410,0001,782
Gill netterGrimsby130220,0001,692

Note: These figures are for the top vessels at the main ports in the two categories.

1 Ref.: Fishing News, February 23, 1979. Fleet St., London EC4A.
: Olsens Fisherman's Nautical Almanac, 1979. Dennis, Scarborough.

While actual fuel consumption in each case is not known, we do know from the Norwegian study and from oil costs in U.K. 1978, that many vessels were averaging $100 per year per hp installed. Using that figure as a guide it would appear that none of the vessels listed with more than 800 hp were viable that year. That would include all but one of the deep sea trawlers. All of the “inshore” vessels (up to 200 miles) performed well. The average power of the 7 smaller vessels is 350 hp and the most productive and economical unit was the 240 hp pair trawler. The actual grossing by the pair team of two 240 hp vessels was $1.5 million.

The foregoing should be sufficient to convince us that the fishing vessels of the future should be relatively small, low-powered, labour-intensive units. For the Indo-Pacific region, this will still mean a considerable range of sizes and types. The 240 hp pair trawler mentioned above would be considered a large capital-intensive vessel compared to the majority of the boats in the Asian fleet.

Figure 14

Large factory trawler
66×13 meters 2,600 hp

Figure 14

Figure 15

Small pair trawler
24×7 meters 420hp

Figure 15

4.2 Traditional Vessels

One would have to recognize that there would be little change in the majority of traditional vessels. The sailing dhow, banca, prahu and compring canoe have proved themselves for generations and will no doubt continue to be used by thousands of artisanal fishermen. It is when these craft are mechanized or when a shift is made to a totally mechanized vessel that the need arises to produce an appropriate design1.

A gentle combination of sail and power would appear to be a logical alternative. Many such craft operate successfully on the west coast of America. Some experiments are currently under way in Europe and Japan to produce viable designs for both fishing and cargo work2. Surprisingly, there has been very little work by U.N. and Government fishery departments on such vessel design. The majority of the examples produced to date have been developed by private fishermen or boat builders.

In part 2, page 10 we considered 5 ways in which we might reduce fuel consumption by fishing vessels. When we mechanize a sailing boat or build a vessel to operate on sail and power, we should consider all possible ways of reducing the fuel requirements to a minimum. So we should give preference to heavy duty slow or medium speed engines, to engines which can operate on biofuels, and to propellers which will give more efficient propulsion. Cruising speed should be reduced to an acceptable moderate figure. Fishing methods low in energy requirements will be used in preference to energy expensive systems wherever possible. Trolling line, jig, long line, gill net and trap fishing are all relatively low in power requirement. If one must undertake some trawling and purse seining activties, and if this can be controlled to prevent over-pressure on stocks, it should be prosecuted in the least costly way relative to fuel consumption. Modern two boat methods of fishing have been proven to be more economical, more productive and less energy expensive in a variety of situations They also provide relatively more employment opportunities for fishermen3.

4.3 Sail and Power

Fishing craft using sail and power are remarkably few in the Indo-Pacific although hundreds of trading dhows and schooners are equipped in this way. A zulu type sail and power fishing boat was recently built in Scotland4. But sailing craft are rare in Europe and Scandinavia. It is to the west coast of America, and the Caribbean waters we must look for working examples of such vessels. Many tuna and salmon trollers use both sail and power. These boats are mostly skippered by their owners. That may be a clue to the reluctance of Asian fishermen to use the system. If the fisherman has no equity in the boat, and if the degree of profit sharing is small, then he will have little incentive to save on fuel. Rather, he will maximize engine use to increase production and reduce steaming time. Perhaps when more fishermen in the region own their vessels, we will see a change in attitude towards economy of operation.

1 Cole, R.C. and Greenwood-Barton, L.H. The Mechanization of Fishing Boats. Tropical Science, Vol. V, Nos. 3 & 4. London, ITP, 1963.

2 Ref.: Windy Solution. Time Magazine, p. 18, September 10, 1979.

3 Thomson, D.B. Pair Trawling and Pair Seining. England, Fishing News Books, 1978.

4 A Way to Sail Out of the Fuel Crisis. Fishing News International, Vol. 18, No. 7, July 1979.

Examples of some American sail and power fishing boats are given in Figure 16. Such vessels work the eastern Pacific from Central America to Alaska. Although they are partly sail powered they are very modern vessels equipped with crew comforts and with echo sounder, radio-telephone and even refrigeration. That degree of sophistication would not be needed for most applications in the Indo-Pacific. Crew requirements are relatively small and this also would be an inappropriate saving in regions where labour costs are low and unemployment is high.

The captain and owner of one of these vessels reports on his experience thus: “We designed the Sail Fisher for fishing albacore tuna and it worked out very well for that purpose. It was 16 meters overall and could carry about 17 tons of frozen fish. Power was 3–71 G.M. diesel engine of around 85 shp which gave an 8.5 knot cruising speed at about 11 liters per hour. This is about half the power of many comparable fishing boats. The trolling and sailing gear were laid out so the boat could be fished under sail, although we seldom did so because the boat was so economical to run and fuel (at that time) easily available. We regarded the sails more as an emergency power source, but in remote areas they certainly could have been used to stretch the fuel supply whenever the wind was favourable, and would allow the boat to prospect for fish in areas where it would not be economical for a power vessel”.

“It would seem to me that sailing fishing boats could be used to advantage in developing fisheries by offering economical operation and unlimited range, and the ability to return to port in the event of mechanical breakdown. The higher initial cost for the sailing rigging is offset by the use of a smaller engine and the savings in fuel”1. Those comments by an experienced Pacific Coast fishermen speak well for the potential benefits of sail and power fishing craft.

1 Short, K.C. Poulsbo, Washington. Personal letter, Nov. 22, 1978.

4.4 Biogas on Fishing Boats

Could biogas be usefully applied to fishing vessel propulsion? The question is an intriguing one and raises the thought of fuel production from fish offal. Certainly a lot of space would be required for the digester and the gas tank, but how many vessels today require all of their hold space?

Let us suppose a 15 meter 100 hp vessel has a fish hold measuring 25m3. The fishermen might easily afford to relinquish 5 or 6 m3 of space to be made into two biogas digesters -- one at each side on the aft end of the fish hold next to the engine room. From two small hatches on deck the crew could load the digesters with fish offal, guts, trash fish and galley waste. The gas tanks would protrude above deck level but they would be protected by large hatch coamings which would be necessary to keep sea water out. The gas from each digester might be fed directly to the engine which could be switched over from regular fuel whenever sufficient gas had been produced.

Figure 16


Figure 16

A - W. Garden/Philbrooks, Sidney B.C. Canada, Western Fisheries journal.

B - E.Monk & son/Shookum Marine, Port Townsend, Washington U.S.A.

C - Le Mesnager, Briscoe, Harlog, California, National Fisherman journal.


Figure 17

A single ton of trash fish or fish offal should produce over 500 m3 of biogas, equivalent to over 310 liters of diesel oil -- sufficient probably for 24 hours continuous engine operation. Storage might be a problem, but if the engine consumed 20 m3 of gas per hour, the two expandable cylindrical gas tanks of reinforced plastic tarpaulin material might measure 2× 3 ½ meters when expanded, giving over 10 m 3 capacity each.

Perhaps some enterprising naval architects and engineers might work on the idea to see whether it would be feasible. (See Figure 17).

4.5 Reducing Costs

Cost saving can be further achieved in the areas of electricity generation, ice preservation and deck equipment. In all of these areas we would be cutting down indirectly on fuel requirements. A small wind driven generator fixed to the mast or wheelhouse of a fishing vessel, could provide all the D.C. current required to operate a small echo sounder and normal vessel lights. A ventilator fan makes an ideal miniature windmill and the whole installation could be effected by an average electrician.

Fish room insulation is very necessary if we are to use ice on our catch, particularly in the tropics. Ice losses due to melting can be as high as 60 percent on boats without insulation. At $20 per ton, and using one ton of ice per week, the savings over just one year could cover the cost of a good quality insulation job.

There seems to be very little technology application for deck work, short of complete mechanization with capstans, winches or net haulers. Seaman of the last century performed most of their tasks with no power assistance. But they had the help of a great range of blocks, tackles, pulleys and hand operated capstans. Here is a technology that needs to be recovered from the past, modernized and adapted to small scale fisheries. It could greatly improve working conditions on fishing boats at a fraction of the cost of mechanical or hydraulic machinery.

The capital cost of fishing boats could be kept low by better methods of construction, careful maintenance for long life, and use of non-corrosive bolts and fittings. Where these are not available, traditional boat builders may use hardwood pegs or tree nails which are far superior to iron nails and probably less expensive.

4.6 Summary

To summarize our discussion of appropriate vessel design for the small scale fisheries of the Indo-Pacific we might say: A move towards the creation of a fleet of relatively small, lightly powered craft, using sail power wherever possible and utilizing less energy-expensive fishing methods would:

  1. reduce capital investment costs

  2. increase employment

  3. maintain production while reducing pressure on overfished stocks; and

  4. considerably reduce the fishing industry's overall fuel costs.

Previous Page Top of Page Next Page