The first requirement for any analysis of the composition of a stock of fish is a reliable method of obtaining representative samples. Where there are no market or mesh restrictions leading to the elimination of small fish from the commercial landings, these may include the full range of sizes and provide good samples of the fishable stock. If the commercial catch is not representative of the stock, it may still supply useful data if the sampling error is known. In most cases, however, special fishing gear operated by fishery research vessels is needed to obtain good samples of all age groups. The fishing grounds are explored using trawls with cod ends covered with fine-mesh net capable of retaining the smallest fish. For pelagic fish, drift nets may be used which include a range of mesh sizes suited to the different sizes of fish in the shoals.
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The Reasons Behind And The Plan To Build A Healthy Ego. It is important for us all to ensure that our egos are strong and healthy. Our ego is our identity. It is who we believe ourselves to be and as such is a reference point and our “home in the world.” The ego is individuality. As our identity it sets us apart from other people’s identity. Get your ego in order here.