In pursuit of modernising fish culture practices, novel recirculatory aquaculture systems (RAS) have been introduced in semi-urban areas of West Bengal and other parts of India. While quite a few progressive fish farmers in India have adopted advanced, intensive and imported RAS systems featuring huge plant, other farmers have developed small and indigenous RAS systems that require comparatively low investment. This article discusses the design, principles, state-of-the-art and associated practical aspects of indigenous RAS technology as currently practiced in West Bengal and other places.

Loricariid catfish species of the genus Pterygoplichthys, known in the aquarium trade as 'plecos' and 'algae eaters', have extensively invaded and proliferated in the East Kolkata Wetlands in West Bengal. Loricariids have capacity to alter the ecosystem and biodiversity of invasion sites, by physically altering the invaded habitats and by competing with native animals for food and space. The aquarium trade pathway is the most significant source of loricariid introductions globally. This article discusses the invasion of loricariid catfish in the East Kolkata Wetlands, and the environmental and economic impact on local fishers.

This disease advisory describes the history, known host range, clinical signs and PCR detection methods for viral covert mortality disease (VCMD). Crustaceans currently known to be susceptible to VCMD include Penaeus vannamei, P. chinensis, P. japonicus, P. monodon, Macrobrachium rosenbergii, Procambarus clarkii, Exopalaemon carinicauda, Ocypode cordimanus, Diogenes edwardsii, Corophium sinense, Parathemisto gaudichaud and Tubuca arcuate. Fish species including Mugilogobius abei, Carassius auratus, and Paralichthys olivaceus may also be susceptible to the virus.

Aquaculture of short-necked clam Paphia undulata in Vietnam started approximately ten years ago, but production has been very small due to the lack of seed supply from hatcheries. The Institute of Aquaculture at Nha Trang University, is the first to conduct artificial seed production research on P. undulata and the first hatchery in Khanh Hoa province to produce seed of this species. This article describes techniques to induce spawning in P. undulata using wet and dry thermal shock stimuli. It also describes broodstock preparation, larval rearing, transportation techniques and the market value of this species.

The 84th edition of the Quarterly Aquatic Animal Disease Report contains information from eleven governments. The foreword discusses meetings of the ad hoc Steering Committee of the Regional Collaboration Framework on Aquatic Animal Health in Asia and the Pacific.

It was with great sadness that we learned that our dear friend Professor Sena De Silva passed away on 6 May, 2020. On behalf of the Governing Council, the Chair Dr Yingjie Liu, and the NACA Secretariat, would like to express our sincere condolences to his family. The aquaculture community, and the region, has lost one of its true champions. We, the staff of the NACA Secretariat, will miss Sena. He was not just a colleague, teacher and mentor, he was also our friend.

Infection with DIV1 is an emerging disease in farmed Cherax quadricarinatus and Penaeus vannamei suffering a high mortality. This disease card provides information on signs of disease at pond and animal level (levels I - III diagnoses), the disease agent, known host range and distribution in the Asia-Pacific region, molecular diagnostic methods and provides key expert contact points.

In this issue:

Potential new species in the Kingdom of Saudi Arabia: Sabaki tilapia (Oreochromis spilurus); Role of fish & fisheries in national nutrition of Pakistan; Success story of first fish farmer in India to be awarded ‘Padma Shri’; Insights into the fishing gear and ichthyofauna of major lentic water bodies of Kashmir Valley; NACA Newsletter.

For the sustainable economic development of Saudi Arabia, the government set up the goals of Vision 2030. In 2030, the Saudi aquaculture industries expect to produce a combined 600,000 tonnes. At present, the total aquaculture production of Saudi Arabia is around 55,000 tonnes. To match the production goal, we need to find some new species to farm. Candidate species should be unique, easy to manage, low cost and have high market demand. The fisheries authority has chosen Sabaki tilapia (Oreochromis spilurus) to be our promotional species. This article describes efforts to establish Sabaki tilapia aquaculture operations in the Kingdom of Saudi Arabia.

The fisheries sector of Pakistan comprises over 290,000 square kilometres of marine waters and 8.6 million hectares of inland water resources including the world’s largest irrigation system and favourable climatic conditions for aquaculture development. Despite these promising circumstances Pakistan stands thirty-third in world fisheries production. This article considers the true fish production potential of Pakistan and makes a comparison with other regional countries that produce more despite having less water resources, e.g. Bangladesh. Considering the ground reality and gaps in fisheries statistics collection, assessment and reporting, the possibility that fish production and consumption are under reported is explored.