4. Aquaculture production trends by species group

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

Eels

Japanese eel production has declined to a stable level of around 22 000 tonnes and that of Taiwan POC has declined greatly to the level of 1999. In contrast, production in China PR has risen steadily, until it peaked in 1997, remaining just below this level since. Australia, Indonesia, Malaysia, Korea RO also produce some quantities through aquaculture.

Barramundi and Japanese Seabass

Barramundi (Lates calcifer) is gaining ground with increasing production in Indonesia from both brackishwater culture and mariculture. Thailand's production has increased but now appears relatively stable, probably due to limited site availability and market saturation. Australian production is also rising. 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 (1 432 tonnes in 2002).

There has been a limited international trade of these species either live or processed and future expansion may be reliant on the development of regional or international markets.

Salmonids - Brackishwater/Mariculture

Culture of salmonids (chinook, coho, Atlantic salmon and rainbow trout) in brackish water and mariculture is reported from Australia, New Zealand and Japan. Japanese coho salmon culture declined sharply in 1995 and hit the lowest point in 1998 dropping to 32 percent of its 1992 production. New Zealand's chinook salmon production is relatively stable.

Australian brackishwater culture of rainbow trout has declined over the past 10 years from 890 tonnes (1990) to zero reported in 1997. In contrast, over the past 10 years the Australian Atlantic salmon industry has developed considerably.

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 in Iran, which has made good progress. Ayu sweetfish (Plecoglossus altivelis) production in Japan has declined about 25 percent in the last decade.

Other carnivorous fish

Over 20 species of other carnivorous finfish are reported and are principally cultured in marine or brackish waters, typically in cages.

Japanese culture of Amberjack (Seriola) is the leader (162 563 tonnes in 2002) and yields are stable. 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 (Rachycentron) culture increased rapidly in Taiwan POC in six years from almost nothing to over 2 400 tonnes in 2002. 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. 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 culture in Australia has emerged as a significant industry for the country over the past ten years reaching 4 000 tonnes in 2002. 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.

Seabream production is confined to Japan, Taiwan POC, Korea RO and Hong Kong SAR. The Japanese production of seabream was 71 866 tonnes in 2002, nearly half that (44 percent) of amberjack.

Other marine finfish not elsewhere identified (nei)

This group of fish is of interest because of the large reported production from China PR. Since the individual species are not reported, trends cannot be determined. Most of these fish are assumed to be carnivorous and are fed by trash fish from the Chinese capture fisheries.

Table 13
Aquaculture production reported under "marine finfish nei"

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 grass-roots 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 reduce as greater rationalization and aggregation of production operations focused onto a small 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 into 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 10 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 14
Tilapia top eight producer States (2002)

Reported exports of tilapia are low. The continuing domestic demand and the high quality required for export targeted fish means that domestic marketing is still attractive in many States.

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 10 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.

Common carp, the third highest production species, is literally the most commonly cultured species in the region; 18 States and areas have reported culturing this species.

Table 15
Carps and barbs top ten producer States (2002)

Although production of the most of species in this group generally exhibits increasing trends, the rate of growth since 1997 for some species has started to show signs of slowing down (e.g. Bighead carp and Rohu).

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.

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). 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 is reducing its production, possibly because of increasing attention to higher value species. Singapore has steadily developed its mariculture of milkfish.

Table 16
Milkfish top seven producer States (2002)

Mullet

Pond based brackishwater culture of mullet is typical but Korea RO is reporting increasing mariculture production since 2000. Indonesia has the largest production of this species and experienced a sharp decline in 1998. 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/brackish water crabs.

Penaeid shrimp culture

Marine shrimp continued to dominate crustacean aquaculture, with two major species accounting for over 48 percent of the total crustacean production in 2002 (the Giant Tiger shrimp, Penaeus monodon; and the fleshy shrimp, P. chinensis). Whilst the giant tiger shrimp ranked 9th by weight in terms of regional aquaculture production in 2001, it ranked 3rd by value at US$ 3.21 billion.

Cultured shrimp production in the region reached one million tonnes in 2002 (accounting for 34 percent of total shrimp landings). The production of P. monodon has ranged between 480 and 610 thousand tonnes since 1993, whilst its contribution to overall shrimp production has declined from 70 percent to 49 percent in 2002, as P. chinensis and other Penaeus shrimp production has increased.

Production trends in the region have increased over the past ten years for the major producers. 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.

Table 17
Penaeid shrimp top ten producer States (2002)

Other major producers, Thailand and Viet Nam, have also encountered fluctuations in production which are primarily associated with the impact of the diseases. Production in the Philippines, India, Sri Lanka and Indonesia has also been affected by the impact of viral diseases (typically WSSV^[26]). Generally the high international market demand has maintained interest in the culture of shrimp for export.

More recently, the introduction of P. vannamei for culture in the Asia region has led to increasing production of this species^[27]. China PR has a large and flourishing industry for P. vannamei with production of more than 270 thousand tonnes in 2002 and an estimated 300 thousand tonnes (71 percent of total shrimp production) in 2003, which is higher than the current production of the whole of Latin America. Other Asian States with developing industries for this species include Thailand (estimated production of 120 thousand tonnes in 2003), Viet Nam and Indonesia (30 thousand tonnes each), Taiwan POC, the Philippines, Malaysia and India (thousands of tonnes each)^[28].

Total production of P. vannamei in Asia was approximately 316 thousand tonnes in 2002, and it was estimated that this would increase to nearly 500 thousand tonnes in 2003, which would be worth some US$ 4 billion on the export market. However, not all the product is exported and a large local demand exists in some Asian States.

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 have dropped dramatically during 2002-2003. 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 and India have recently increased the production of freshwater prawns (their respective productions were zero and 311 tonnes in 1994 as compared to 113 743 tonnes and 30 500 in 2002). Other producers have had relatively stable productions.

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.

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.

Table 18
Freshwater prawn top eight producer States (2002)

Crabs

Chinese river crab (Eriocheir sinensis) and Indo-Pacific swamp crab (Scylla serrata) constituted the major cultured crabs in the region. Chinese production of this freshwater crab and marine crabs^[30] has shown very strong growth since 1994 and they were ranked 11th and 4th respectively among the region's top culture production species in inland and marine waters in 2002. Indo-Pacific swamp crab showed relatively stable production trends for the past decade.

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).

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 supply^[31] projected increasing mollusc production, although this may have been based on current production trends rather than the 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 19
Lower value molluscs top ten production (2002)

Table 20
Higher value molluscs top ten production (2002)

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. 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 21
Aquatic plants top ten producer States (2002)

Seaweeds for food purpose

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 (41 percent in 2002). Its production was doubled from two million tonnes in 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.

Seaweeds for biopolymers

This group consists of Eucheuma, Gracilaria, red seaweeds and others. The Philippines has the highest production of these aquatic plants and Eucheuma cottonii (Zanzibar weed) production in the Philippine far exceeds the production of other seaweeds (778 thousand tonnes in 2002).

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.

Table 22
Aquatic plants top ten cultured species (2002)

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

There are limited data on frog production, although frogs are being increasingly cultured in many States. 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.

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.