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Mass fish mortalities was recorded, a day after the Typhoon Lekima passed the coastal areas at Penang, Malaysia in August 2019, which caused huge losses among the fish culturists. Being within the vicinity of a National Park, one would think that the water qualiy around a protected area should be of pristine quality but obviously it is not. Scientists and researchers from both Universiti Sains Malaysia and Department of Fisheries, with the help from NaFish have conducted several tests on the water and fish. The dead cultured fishes were mainly groupers, which prefer to stay at the bottom of the nets. The storm created by Typhoon Lekima had churned up all sediments in the shallow coastal areas. This had caused additional sediment and nutrients in the ecosystem, leading to algal bloom and also depletion of oxygen levels in the water, causing mass fish mortality. Water quality monitoring (physical, chemical and biological) was conducted along the coastal areas as well as extending towards the sea and at different depth to further understand the causes of fish kills over a period of three weeks after the incident. Sampling was done 3-days, 11-days and 26 days after the typhoon, Results had shown extremely low dissolved oxygen and high concentrations of nitrate, nitrite and chlorophyll a recorded after the typhoon. However, water quality slowly became normal and within the Malaysian Marine Water Quality Criteria & Standard for Class 2-Marine Life, Fisheries, Coral Reefs, Recreational & Mariculture.

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Culturing of bivalves in the hatchery is the most popular technique for aquaculture that promotes a healthy bivalve's production, where the animal would be less exposed to pollution from human activities. The increase of industrial and agricultural waste along the coastal region has altered the environment, hence affecting the growth and survival of aquatic organisms, particularly clams which is one of the sources of protein to coastal communities. Due to the high demand for blood cockles and drastic change in term of production from culture site, the price of blood cockle per kilogram has increased. Thus, this study aimed to observe the growth development of blood cockles (Tegillarca granosa) using different substrates in a hatchery system. In this study, adult cockle from Kuala Juru, Penang on the northern Straits of Malacca were collected from wild and maintained in hatchery system at Centre for Marine and Coastal Studies (CEMACS), Universiti Sains Malaysia (USM). 50 individuals of adult cockle were used for each treatment. The growth characteristics, such as weight, length, thickness, and height of the cockle samples were monitored in both sand and mud substrate experiment tanks until the end of their survival. Generally, both substrates showed an increment in the growth characteristics from initial measurement. Increase in growth characteristics of cockle samples in the sandy experimental tank were, 3.919±0.717 g in weight, 22.90±1.72 mm in length, 15.30±1.69 mm in thickness and 17.40±1.87 mm in height at the end the experiment. Meanwhile, cockle's culture in mud substrate showed growth of an average weight of 7.410±2.022 g, 27.40±2.98 mm in length, 17.60±1.94 mm in thickness and 20.60±2.06 mm in height. Furthermore, cockle samples in sandy substrate particularly showed a higher survivability of up to 4 months, compared to mud that only survived for two months. Therefore, this preliminary study suggest that blood cockle could be cultured using a sand type substrate as an alternative to mud in the hatchery system.