Renewable Resource: ~ Fish & Fishing Activities ~
Content • Importance of fish to human • Cause of over-fishing andits impacts on the environment • The ways to ensure sustainability of fisheries in Hong Kong
Importance of fish to human – For Commercial purpose • As food supply ．To compensate essential nutrientsabsent in rice (protein, oil, Vitamins andminerals ) ．Less cholesterol than the other food • Marine fishing ．To support the living of about 200 million employees in related industries globally
Importance of fish to human – For Recreational purpose • Fishing as an outdoor activity • For appreciation and relaxation
Fish Protein ~ • Fish protein is necessary for physical growth and maintenance (amino acids) • Fish protein is highly digestible and has favorable taste
Fish Oil ~ • Polyunsaturated fatty acids in fish oil can decrease blood triglyceride and cholesterol • Fish helps maintain a healthy heart and lowers the risk of stroke and heart attack
Fish Vitamins ~ • Vitamin A is present in fish as retinol, which is readily absorbed and utilized by humans • Vitamin D is present in seafood
Fish Minerals ~ • Fish iron is necessary for hemoglobin formation in the blood • Calcium and phosphorus are essential for bone formation • Iodine avoid causing goiter and cretinism and retarding growth
Cause of over-fishing • Demand of fish increase as population growth of people • The massive overcapacity of fishing fleets which leads to great pressure from fisheries on the dwindling fish stocks • New technologies and fishing methods • Economic development
Impacts on the environment • Threat to ocean health are exacerbated • Fishing down the food web ( the systematic removal of the largest top-level predators ) • Cause serial depletion • Alter the composition of entire ecological communities
Alter the relationships of prey to predators and thereby pose risks to entire ecosystems • Global warming • Changes in ocean currents
The ways to ensure sustainability of fisheries in Hong Kong • Aquaculture Development • Fisheries Management & Development • Fisheries Legislation • Others
Aquaculture Development –by Agriculture, Fisheries and Conservation Department • To identify suitable new species with good market potential for extension to farmers (Jade Perch, Tinca sp. and Chinese Long Snout Catfish) • To develop feed formulations to replace trash fish, traditional feed for aquaculture • To provide assistance on fish culture techniques and related management problems encountered
New Species of Fish ← Jade Perch ↑Chinese Long Snout Catfish ←Tinca sp.
To provide assistance in disease diagnosis and advice on appropriate treatment measures • To provide initiatives • To conduct regular water quality monitoring at fish culture zones • To implement an enhanced phytoplankton monitoring programme
Fisheries Management & Development -by Agriculture, Fisheries and Conservation Department • The proposed fisheries management measures include a territorial-wide fishing license system • Artificial reefs are able to encourage growth and development of a great number and variety of marine organisms
To commissioned a consultancy study to examine the technical and financial feasibility of developing an offshore fishing for Hong Kong • To launch the Hong Kong Fish Net (www.hk-fish.net) to help raising the public awareness on the need and importance of fisheries resources conservation in Hong Kong www.hk-fish.net
Fisheries Legislation -by Agriculture, Fisheries and Conservation Department • The Fisheries Protection Ordinance (Cap 171) : ．destructive fishing practices (electricity, explosive, toxic substances, dredgingand suction devices) are banned Electricity: ．destroy nearby small fish and planktons
Explosive substances: ．destroy nearby small fish and even planktons ．destroy the related food chains and cycles of the marine ecosystem Toxic substances: ．poison the neurosystem of the target fish ．would kill nearby small fish and other marine lives such as corals Dredging and suction devices: ．affect the seabed ．damage to the fisheries resources
The Marine Fish Culture Ordinance (Cap. 353) : ．require all marine fish culture activity to operate under licence in designated fish culture zones
Others • Closed-fishing (April to August) • Control marine water quality ．Indicate the state of health of marine waters ．Assess compliance with the statutory Water Quality Objectives (WQOs) ．Reveal long-term changes in water quality ．Provide a basis for the planning of pollution control strategies
Levels of compliance with key water quality objectives (WQOs) in Hong Kong Waters
The scientific vessel, the Dr. Catherine Lam it is equipped with a satellite-aided global positioning system for accurate location of sampling stations at sea