Aspects of the fishing industry and an overview of artificial reefs and fish aggregating devices for increasing fisheries output and viability in Nigeria

Aspects of the Nigerian fishing industry are outlined to explain the concept of fishing systems viability which is often influenced by a combination of factors including biological productivity, as well as technical, economic and social factors. The productivity of the aquatic environments can be increased by the construction and installation of artificial reefs and fish aggregating devices. These man-made structures provide shelters, food and breeding grounds for fin fish and shell fish. The habitat enhancement techniques are appropriate, efficient, cheap and simple strategic options for increase in fish production. Recommendations for effective utilization and long term management are outlined.

History of the Atlantic Pearl-Oyster, Pinctata imbricata, Industry in Venezuela and Colombia, with Biological and Ecological Observations

In the 1500’s, the waters of Venezuela and to a lesser extent Colombia produced more natural pearls than any place ever produced in the world in any succeeding century. Atlantic pearl-oysters, Pinctata imbricata Röding 1798, were harvested almost entirely by divers. The pearls from them were exported to Spain and other European countries. By the end of the 1500’s, the pearl oysters had become much scarcer, and little harvesting took place during the 1600’s and 1700’s. Harvesting began to accelerate slowly in the mid 1800’s and has since continued but at a much lower rate than in the 1500’s. The harvesting methods have been hand collecting by divers until the early 1960’s, dredging from the 1500’s to the present, and hardhat diving from 1912 to the early 1960’s. Since the mid 1900’s, Japan and other countries of the western Pacific rim have inundated world markets with cultured pearls that are of better quality and are cheaper than natural pearls, and the marketing of natural pearls has nearly ended. The pearl oyster fishery in Colombia ended in the 1940’s, but it has continued in Venezuela with the fishermen selling the meats to support themselves; previously most meats had been discarded. A small quantity of pearls is now taken, and the fishery, which comprised about 3,000 fishermen in 1947, comprised about 300 in 2002.

Role of the state and financial institutions in financing the fishing industry

The experience of the Government in the recovery of loans for 28 foot mechanized vessels has been unsatisfactory. The author examines the various aspects which have contributed to this situation, and considers arrangements for financing purchase of such vessels. The risks associated with the investment in 38 foot vessels are high, and it seems that the reluctance of private investors to make the required contribution from personal funds is a result of fear of the unknown. Current incentives provided by the Government to the private sector for the purchase of 38 foot vessels are considered to be adequate.

A History of the Pearl Oyster Fishery in the Archipielago de las Perlas, Panama

The pearl oyster, Pinctada margaritifera mazatlanica, was once found around the Archipielago de las Perlas in Panama in abundance and it supported a substantial fishery by hard hat divers. The products were pearls, shells used for making buttons, and meats used locally for food. After the mid 1920’s, the fishery declined due to overfishing, and by the 1940’s it was nearly gone. The oysters began to repopulate the grounds during the 1970’s, but the oysters remain relatively scarce. Fishing has since resumed on a small scale by skin divers using face masks.

The Feasibility of Enhancing Red Sea Urchin, Strongylocentrotus iranciscanus, Stocks in California: An Analysis of the Options

The California fishery for red sea urchins, Strongylocentrotus franciscanus, has undergone explosive growth in recent years and is approaching full exploitation. Thus, there is considerable interest in enhancing stocks to maintain a high rate of landings. Fishable stocks of red sea urchins in different areas appear to be limited at three stages in their life history: By the availability of larvae, by the survival of newly settled to mid-sized animals, and by the food available to support growth and reproduction of larger animals. Here I review other efforts, notably the extensive Japanese work, to enhance fishable stocks of benthic marine invertebrates, and consider the potential options for red sea urchins at different points of limitation. These include collecting or culturing seed for outplanting, physical habitat improvement measures, improving the food supply, and conservation measures to protect existing stocks until alternate methods are proven and in place. The options are compared in terms of biological feasibility, capital and labor requirements, and potential implications for change in the structure of the fishing industry.