4. Status of Aquaculture

This part of the document will deal with the review of major groups of species that are currently cultured in the Asia-Pacific region. The manner of grouping species will be according to the trophic needs of the species and in some cases the degree of reliance on external inputs (such as feeds and infrastructure for culture).

4.1 Carnivorous species or species requiring higher production inputs

Freshwater carnivorous species

Eels

During the period 1988 to 1998, the world's aquaculture production of eels doubled from 98 000 tonnes to 217 000 tonnes, of which 95 percent was produced in Asian farms.

Eel production in Japan (Anguilla japonica) has remained stable for the past ten years at around 20 000 tonnes. The production of Taiwan POC has declined greatly to the lowest level in 1999. In contrast, production in China PR has risen steadily, until a peak in 1997, remaining just below this level until reaching a new high in 2004 at a level of 178 176 tonnes.

This production is reported as Japanese eel, however, China PR also imports European glass eels (Anguilla Anguilla) and hence some of this reported production would be the European eel. In 2004, Chinese swamp eel production was also high at 137 486 tonnes for 2004. Malaysia and Korea RO also produce some quantities of Japanese eel through aquaculture.

Europe has increasingly supplied Asian eel farms with glass eels, and the region has gradually become more dependent on wild-caught eels of Europe. In 1997, for example, France exported more than 2 66 tonnes of European eels to destinations outside the EU (amounting to 55 percent of all EU eel exports outside Europe that year).¹

Salmonid - Freshwater culture

Freshwater production of trout species in the region has been fairly stable over the last decade with the exception of the development of the industry of Rainbow trout in IR Iran, which has almost doubled production in two years (to 30 000 tonnes). Ayu sweetfish (Plecoglossus altivelis) production in Japan has declined by about 25 percent in the last decade (7 200 tonnes).

Catfish

The top five producing states are China PR, Thailand, Indonesia, India and Malaysia. Total production in 2004 was 652 386 tonnes and China PR produced 58 percent of the total production. China started to report on this group in 2003. The production (without China) shows a slow increasing trend with an average growth rate of 11 percent. This would be greater if Vietnamese production of Pangasius was also included (Viet Nam does not report Pangasius separately from "freshwater fish nei").

The top five species are Amur catfish (Silurus asotus) , Torpedo-shaped catfishes nei (Clarias spp.), Hybrid catfish (C. batrachus x C. gariepinus), Yellow catfish and Channel catfish (approx 90 percent of the total production for the group). In addition, Viet Nam produces significant quantities of catfish of the Pangasius spp. Viet Nam produced over 300 000 tonnes in 2004 which is a significant increase over the estimated 180 000 tonnes for 2003.²

Snakeheads

The total production in 2004 was 285 173 tonnes and the top four producing states are China PR, India, Indonesia and Thailand. China PR has just started to report snakehead production separately (as with the catfish) in 2003. In 2004 China PR produced 84 percent of the total Asian production.

The trend for this goup is hard to define. Indonesia and Thailand show a stable trend at a low level (approx 6 600 tonnes). India has fluctuated in the past ten years with a high in 2000 of 80 740 tonnes and a low in 2001 of 1 301 tonnes but is again showing an increase to almost 30 000 in 2004. The production in China PR increased by 35 percent to 238 754 tonnes (2003 to 2004).

Knifefish and gobies

These species are not widely cultured but have a good market price in certain countries. The sand goby production in Asia is almost totally based on on-growing of wild caught fingerlings. The total production of Knifefishes and Marble goby was 214 tonnes in 2004. Malaysia is the top producer, followed by Indonesia, Singapore and Thailand.

Thailand has shown a declining trend. In Malaysia production has declined by half in a five year period to around 100 tonnes in 2004, except for a peak in 2003 of 700 tonnes.

Marine and brackish water carnivorous species

Barramundi and Japanese Seabass

Barramundi (Lates calcifer) is gaining ground with the regional total reaching 29 884 tonnes in 2004. Thailand has become the top producer in the region with a still increasing trend. The Thai production is still largely marketed domestically. There has been a significant reduction in production from Hong Kong SAR which may be due to a shift towards higher value species and limited site availability. Korea RO is also producing Japanese seabass (Lateolabrax japonicus, 1 850 tonnes in 2004). China PR has also reported large production of Japanese seabass starting in 2003 and 2004 (217 000 tonnes in 2004), which may be an effect of China PR's improved reporting on individual species (these species may have previously been reported under marine finfish nei).

There has been limited international trade of these species either live or processed and future expansion may be reliant on the development of regional or international markets. There is some interest in Lates niloticus , the Nile Perch which has particularly white flesh and is widely traded as a commodity; Lates calcarifer does not have such good flesh colour, but may still offer some potential as an alternative in some markets.

Salmonids - Brackishwater/Mariculture

Culture of salmonids (chinook, coho, Atlantic salmon and rainbow trout) in brackishwater and mariculture is reported from Australia, New Zealand and Japan and is currently at 29 631 tonnes. Japanese coho salmon culture had a peak in 1991 and has declined sharply in 1995 and hit its lowest point in 2002 dropping to 31 percent of its 1991 production. In 2004 the production reached 9 607 tonnes. New Zealand's chinook salmon production is relatively stable at just over 5 000 tonnes.

Australian brackishwater culture of rainbow trout has declined over the past ten years from 890 tonnes (1988) to zero reported in 1994. In contrast, over the past ten years the Australian Atlantic salmon industry has developed considerably to a current figure of 14 828 tonnes in 2004.

Marine and brackishwater carnivorous fish

Over 40 species of marine and brackishwater carnivorous (or largely carnivorous) finfish are reported and are largely cultured in cages.

Japanese culture of Amberjack (Seriola) is the leader with production stable at 150 068 tonnes in 2004. The production of several other Japanese species is also quite stable (such as pufferfish, several mackerel species and bastard halibut) and it is assumed that this is due to site limitations which effectively prevent further expansion. In Japan and Korea RO particularly, it is inevitable that there will be a turn towards imports from neighbouring States such as China PR.

Cobia

Cobia (Rachycentron) culture increased rapidly in 13 tonnes in 1996 to 2 400 tonnes in 2002 and was 20 461 tonnes in 2004 (this is largely because of China PR reporting this species separately). Chinese production in 2004 was 16 493 tonnes. Taiwan POC reports a production of 3 968 tonnes for 2004. Culture of this species is also taking off rapidly in other States such as Viet Nam and Thailand, possibly as a result of the increasing availability of fingerlings from Taiwan POC (however, this is not yet being reported widely, therefore the total production can be considered conservative). The very rapid growth rate of this species and relative hardiness in ponds makes it an attractive species for aquaculture, although market acceptance is not yet definite.

Southern Bluefin Tuna

Southern Bluefin Tuna culture in Australia has emerged as a significant industry for the country over the past ten years reaching 4 000 tonnes in 2002 and stayed at this level in 2004. Although the quantity is relatively low compared with the Japanese Amberjack production, the very high value of this product makes it a significant economic activity where it is practiced.

The total value of the Australian Southern Bluefin Tuna wild harvest component of the fishery was approximately US$50.5 million, and the value- added from grow out of wild caught fish in seacages is approximately US$97.3 million³(2002-2003) .

Seabream

Seabream production is confined to Japan, China PR, Taiwan POC, Korea RO and Hong Kong SAR. The Japanese production of seabream was 80 959 tonnes in 2004, more than half that (54 percent) of amberjack. China PR has started reporting over 40 000 tonnes starting from 2003. The production of this species was probably reported earlier as Other marine finfish nei.

Other marine finfish not elsewhere identified (nei)

Most of these fish are assumed to be carnivorous and are fed by trash fish from the Chinese capture fisheries. China PR production of European turbot is estimated at about 3 000 tonnes representing about 33 percent of global aquaculture production.⁴

This group of fish is of interest because of the large reported production from China PR. Even though China PR has decreased its reporting on nei species by 64 percent since 2002, the quantity of "marine finfish nei" reported by China PR equals the total aquaculture production of Malaysia. Since the individual species are not reported, trends cannot be determined.

It is important to point out that an increase in trends for a species most likely is a result of improved reporting on individual species. Table 18 and Figure 33 show the apparent drop in production for China PR between 2002 and 2004, an artefact caused by improved detailed reporting of individual species.

Table 18
Aquaculture production reported under "marine finfish nei"

Figure 33
Trend in reporting by species for marine fishes in China PR (1 000 tonnes)

4.2 Finfish requiring lower inputs

Freshwater omnivorous and herbivorous fish have been important food fish for developing States in the Asia-Pacific region. Traditional production methods have become diversified and intensified, starting with fertilized polyculture systems and moving towards systems using supplemental feeds and even complete feeds. As demand for fish increases and prices rise, further pressure on intensification and the use of feeding can be expected in many States.

Backyard ponds are an increasingly common sight in many States; however, this production is frequently missed in national statistical surveys due to the small unit size. In many cases ponds may be below the size required for registration and production from them is not viewed as a significant economic activity. However, the large numbers of these ponds and the aggregated production and value to the households engaging in the activity is probably very significant. The lack of reliable information from this part of the sector currently limits evaluation of the grassroots impact of rural aquaculture in the Asia-Pacific region.

It has been suggested that the wide range of species that are currently produced from aquaculture will decrease as greater rationalization and aggregation of production operations focus on a smaller number of species. This lesson has been taken from the livestock sector and is considered to be an essential part of the "industrialization" of aquaculture. This trend does not appear to be the case so far in the Asia-Pacific region with farmers increasingly seeking out new species that give them a marketing or profit advantage.

Tilapia

This "industrialization" trend is seen in some States with species such as tilapia. There is a trend towards standardization of size, feeds and production systems, some quality control, avoidance of off-flavours, and marketing in supermarket chains.

However, even with tilapia, there is still considerable flexibility of systems, strains and colours of fish. There is probably more diversity in tilapia culture systems today than ten years ago with a range of characteristics including:

• Colouration (red, white and black strains)
• Monosex and mixed sex
• Pellet fed, supplemental feed and fertilized greenwater
• Freshwater and brackishwater
• Cold tolerance

Table 19
Tilapia top eight producer States (2004)

Reported exports of tilapia are still low (~9 percent) relative to total regional production. The continuing domestic demand and the high quality required for export targeted fish means that domestic marketing is still attractive in many States. The biggest exporter of frozen whole tilapia and frozen fillets to the USA was China (Mainland and Taiwan Province), which accounts for virtually all imports of this product by the USA⁵ (Table 20).

Table 20
Countries exporting tilapia (2004)

Carps and Barbs (cyprinids)

Carps and barbs continue to be the most popular species group among Asia-Pacific States dominating eight ranks of the top ten freshwater species by production. Their production is particularly important in terms of the vital supply of protein in major populous States in the region such as China PR, India and Bangladesh.

Silver carp has maintained the highest production for decades. Grass carp was once in a distant second place but has recently closed the gap between the two species and was in 2004 at the same level.

Common carp, the third highest production species, is literally the most commonly cultured species in the region; 20 States and areas have reported culturing this species (Table 21).

Table 21
Carps and barbs top ten producer States (2004)

Although production of most species in this group generally exhibits increasing trends, the rate of growth since 2001 for Silver carp has started to show signs of slowing down.

There are reports that the profitability of production of these species in India and China is declining and farmers are starting to explore the production of alternative higher value species. Since the markets of these species are largely domestic, there is little opportunity for export, although India, for example, does export to neighbouring Nepal and Bangladesh.

Pacus and Pirapatinga (Collossoma spp. and Piaractus spp.)

These Latin American species are not reported in detail for most countries grouped under "Freshwater species nei". China PR has started reporting production of Piaractus (86 409 tonnes) separately.

Freshwater fish nei

Statistics from China PR have reported the reduction of "Freshwater fish nei" from 2 million tonnes in 2002 to less than 540 000 tonnes in 2004. These fish are now reported by species and, interestingly, are mostly carnivorous species with the exception of Pirapatinga (Piaractus brachypomus). The species which are now reported in detail are Amur Catfish (245 874), Snakehead (238 754) , Swamp eel (137 486) , Pirapatinga (86 409), Pond loach (79 409), Yellow catfish (63 062), Channel catfish (62 618), Sea trout (11 869), Sturgeons nei (11 269) , Pond smelt (10 056), Chinese longsnout catfish (5 938) and Salmonids nei (2 366).

Milkfish

Milkfish culture is a strong tradition in the Philippines which reflects the country's preference for the species. There are also traditions of milkfish culture in some of the Pacific Islands (Kiribati, Nauru, Cook Islands and Palau). Of these countries only Kiribati reports production to FAO. Milkfish have typically been produced in brackishwater ponds but there is an increasing trend in reported mariculture production, indicating the use of more intensive cage systems. These systems are fed with either pellets or trash fish and are part of the general trend of intensification of mariculture in the Philippines.

Indonesia and the Philippines are traditionally the largest producers. Taiwan POC is reducing its production, possibly because of increasing attention to higher value species. Singapore has steadily developed its mariculture of milkfish (Table22).

Table 22
Milkfish top four producer States (2004)

Mullet

Pond based brackishwater culture of mullet is typical but Korea RO has been reporting increasing mariculture production since 2000. Indonesia has the largest production of this species and experienced a sharp decline in 1998 but shows a fluctuating increasing trend. Taiwan POC has relatively stable production but has seen a gradual reduction in production. Thailand has greatly reduced production in recent years.

4.3 Crustaceans

Whilst a number of crustacean species are cultured, the predominant commercial species are brackishwater shrimps, freshwater prawns and freshwater/brackishwater crabs.

Penaeid shrimp culture

Marine shrimp continued to dominate crustacean aquaculture, with two major species accounting for over 56 percent of the total crustacean production in 2004 (the White leg shrimp, Penaeus vannamei and Giant Tiger shrimp, Penaeus monodon) . White leg shrimp production in Asia-Pacific increased from 2 000 tonnes in 2000 to over a million tonnes in 2004. A significant amount of this production comes from China PR (735 055 tonnes) and Thailand (276 600) as well as increasing amounts from Indonesia and Viet Nam. Many other countries are now producing this species, however, not yet at a level where it is entering the statistics.

Whilst the White leg shrimp ranked 10^th by weight in terms of regional aquaculture production in 2004, it ranked 1^st by value at US$3 684 million.

Cultured shrimp production in the region reached 2.6 million tonnes in 2004 (accounting for 65 percent of total shrimp landings). The production of P. monodon has ranged between 560 000 and 720 000 tonnes since 1994, whilst its contribution to overall shrimp production has declined from over 70 percent to 33 percent in 2004, as P. vannamei production has drastically increased. P. chinensis had a stable increase during the 1990's but has decreased since 2002 to its lowest level since 1985.

Production trends in the region have increased over the past ten years for the major producers (Table 23). China PR suffered a major setback in the mid-1990s due to the occurrence of viral diseases in shrimp culture, but since that time production has slowly recovered and has been increasing rapidly in recent years.

Table 23
Penaeid shrimp top ten producer States (2004)

Other major producers, Thailand and Viet Nam, have also encountered fluctuations in production which are primarily associated with the impact of diseases. Production in the Philippines, India, Sri Lanka and Indonesia has also been affected by the impact of viral diseases (typically WSSV⁶). Generally, high international market demand has maintained interest in the culture of shrimp for export.

Total production of P. vannamei in Asia was approximately 1.1 million tonnes in 2004. The main reason for the importation of P. vannamei to Asia has been the poor performance, slow growth rate and disease susceptibility of the major indigenous cultured shrimp species, P. chinensis in China PR and P. monodon virtually everywhere else. Shrimp production in Asia has been marred by serious viral pathogens causing significant losses to the culture industries of most Asian States over the past decade. It was not until the late 1990s that, spurred by the production of the imported P. vannamei, Asian (and therefore world) production levels began to increase again.

There are problems associated with this dramatic increase in the production of P. vannamei in terms of marketing of the product. With so many States now producing essentially the same product, global prices dropped dramatically during 2002-2003. There has been a trend towards decreasing shrimp prices for a number of years now. This has follow-up effects regarding the actual value of the product sold and disagreements regarding possible "dumping" of shrimp onto markets.

Freshwater prawns

China PR and India have recently increased the production of freshwater prawns (their respective production levels were zero and 311 tonnes in 1994 as compared to 339 913 tonnes and 38 965 in 2 004) . Even Thailand and Bangladesh show increasing trends in production of freshwater prawns. Other producers have had relatively stable production levels (Table 24).

Table 24
Freshwater prawn top eight producer States (2004)

Since it is not easy to intensify production of freshwater prawns due to their territorial habits and divergent growth effects, the development of this sector is reasonably slow. In some States the sector has shrunk, as attention and resources have been diverted to brackishwater shrimp production. There have also been significant increases in the production of L. vannamei and other Penaeid shrimp in freshwater (or extremely low salinity systems inland). Reported production is very low (only 4 611 tonnes of L. vannamei are currently reported from freshwater production) and does not reflect the fact that there is substantial production of this species in inland areas.

Although the principle species cultured in freshwater (M. rosenbergii) does not suffer the same problems with viral diseases that impact the brackishwater shrimp industry so severely, export markets for freshwater prawns are much smaller and less developed. This is because consumers in general are not as familiar with these species as with brackishwater shrimp. Freshwater prawns, however, enjoy good domestic markets, especially in South and Southeast Asian States.

Crabs

Chinese river crab (Eriocheir sinensis) and Indo-Pacific swamp crab (Scylla serrata) constituted the major cultured crabs in the region. China PR production of Eriocheir sinensis and marine crabs⁸ has shown very strong growth since 1994 and they were ranked 14^th and 4^th respectively among the region's top cultured crab species in inland and marine waters in 2004. Indo-Pacific swamp crab showed stable increasing production trends for the past decade. The reporting of marine crabs nei from China PR has declined from 178 185 tonnes in 2002 to around 10 000 tonnes in 2004. At the same time, the named species of Indo-Pacific swamp crab and Swimming crabs etc., nei has increased from zero to 108 503 tonnes and 74 625 tonnes respectively.

4.4 Molluscs

Mollusc culture is split into low value species produced in extensive cultured systems (e.g. seeded blood cockle mudflats, mussel and oyster stake culture) and high value species produced in intensive systems (fed systems, and possibly recirculation).

Recent improved breakdown by species of aquaculture production of Chinese molluscs has given a better indication of the proportion of low and high value mollusc production. Reported production of "Molluscs nei" in China PR has dropped from 1.25 million to 800 000 tonnes.

Whilst it is possible to separate species such as Abalone or Giant clam as high value species, there are difficulties with some species such as mussels that may be cultured in low input systems in one country (e.g. Thailand) but relatively high input in another (e.g. New Zealand). Many States report their mollusc production in a large grouping such as marine molluscs nei.

The IFPRI/WFC outlook on fish supply⁹ projected increasing mollusc production, although this may have been based on current production trends rather than resource potential. The issue of site availability is likely to constrain future development of mollusc culture in several States as can be seen for the examples of Japan and Korea RO (Table 25 and 26). In these two States, the production of molluscs and seaweeds has been relatively stable for many years. This indicates that suitable sites may now all be taken.

Table 25
Lower value molluscs top ten producer (2002)

Table 26 
Higher value molluscs top ten producer (2002)

Unlike fish culture, the intensification of mollusc culture is quite difficult and probably not economically viable. The trend in mollusc culture is more likely to be a shift from lower value species to higher value species in those areas where sites are suitable.

A further dimension is the development of intensive on shore culture operations such as those for abalone and a number of gastropod species.

4.5 Aquatic plants

Aquatic plant production can be divided into two distinct groups. The first group consists of seaweeds of temperate waters solely and traditionally used for food purposes and the second group consists of tropical species mainly processed as a source of commercially valuable biopolymers (carrageenan, agar) that are used for various food and non-food purposes (Table 27).

Table 27
Aquatic plants top ten producer States (2004)

Seaweeds for food purposes

This group includes Japanese kelp, laver (Nori), green laver and Wakame. The production of these species is confined to East Asian States and has a relatively stable production.

The only exception to this is Japanese kelp culture, which has the largest share of production (33 percent in 2004). Its production doubled from two million tonnes in the three years to 1993 and another one million tonnes was added in the next six years. This rapid increase was probably due to continued expansion of cultured areas in China. Production of Japanese kelp peaked in 1999 and since then has stabilized, which might indicate that the rapid expansion of production area reached a limit and further sites are not available.

Recent detailed reporting from China PR has given a clearer picture of aquatic plant production (Table 28).

Seaweeds for biopolymers

This group consists of Eucheuma, Kappaphycus, Gracilaria, red seaweeds and others. The Philippines has the highest production of these aquatic plants and Eucheuma cottonii (Zanzibar weed) production in the Philippines far exceeds the production of other seaweeds (one million tonnes in 2004).

Table 28
Aquatic plants top ten cultured species (2004)

New areas are being investigated for the expansion of seaweed production since global demand for carrageenan and other alginates is expected to continue to rise.

4.6 Reptiles and amphibians

Reported species are soft shell turtle, crocodiles and frogs. China PR has greatly increased its reported production of soft-shell turtle in the past five years. The production of soft-shell turles in China PR has increased by 77 percent in five years to total production of 163 257 tonnes. Other states who reported production of turtles are Thailand, Taiwan POC and Korea RO.

There are limited data on frog production, although frogs are being increasingly cultured in many States. China has reported production of 73 837 tonnes of frogs in 2004. The small size of a typical frog farm (using small cement tanks or even pens) means that quantification of this type of operation is problematic.

Crocodile production is growing quickly in the region with Cambodia exporting juvenile crocodiles to both Viet Nam and China PR. Thailand and Papua New Guinea also have crocodile farms. This production is rarely reported in fishery or aquaculture statistics.

4.7 Niche aquaculture species

There are a number of niche aquaculture species that this review does not cover with statistical information. These species are either cultured at the pilot/experimental level or simply not reported by many States. Some of the species are not food type commodities (e.g. sponge and pearls, ornamental shells, ornamental fish) and are therefore not routinely monitored by the authority reporting fisheries information (Table 29).

Table 29
Niche aquaculture species (2004)

¹ TRAFFIC report http://www.traffic.org/dispatches/archives/march2001/eel.html

² http://www.globefish.org/index.php?id=2 2 91& easysitestatid=626311130

³ http://www.afma.gov.au/fisheries/tuna/sbt/default. htm http://www.australianaquacultureportal.com/PDF/ industry_bluef in_1 .pdf

⁴ http: //www. ices. dk/committe/acfm/comwork/report/2005/ may/Wild%20cultured%20fish%20interactions.pdf

⁵ http://www.eurofish.dk/indexSub.php?id=3059

⁶ Shrimp White Spot Syndrome Virus.

⁷ This figure was reported as freshwater crustaceans nei., which was most likely freshwater prawn production, and hence it is included here.

⁸ Although the species name is not specified in China PR official statistics, it is most likely Indo-Pacific swamp crab.

⁹ Delgado, C.D, Wada, N., Rosegrant, M.W., Meijer, S. and Ahmed, M. (2003). Fish to 2020. Supply and demand in changing global markets. WorldFish Center Technical Report 62. 226 pp.