Ecology and management of water plants in lowland streams

A review article which discusses the ecology and management of common water plants in lowland streams, with an introduction containing a review of previous studies on the subject. The article covers the significance of seasonal growth, the significance of stand structure (particularly in relation to hydraulic resistence), an assessment of current river management, improvements to plant management techniques (in relation to cutting), and alternatives to the traditional techniques of river plant management. There are a number of accompanying figures.

Biology and Management of the American Shad and Status of the Fisheries, Atlantic Coast of the United States, 1960

This paper summarizes current information on the American shad, Alosa sapidissima, and describes the species and its fishery. Emphasis is placed on (1) life history of the fish, (2) condition of the fishery by State and water areas in 1960 compared to 1896 when the last comprehensive description was made, (3) factors responsible for decline in abundance, and (4) management measures. The shad fishery has changed little over the past three-quarters of a century, except in magnitude of yield. Types of shad-fishing gear have remained relatively unchanged, but many improvements have been made in fishing techniques, mostly to achieve economy. In 1896 the estimated catch was more than 50 million pounds. New Jersey ranked first in production with about 14 million pounds, and Virginia second with 11 million pounds. In 1960 the estimated catch was slightly more than 8 million pounds. Maryland ranked first in production with slightly more than 1.5 million pounds, Virginia second with slightly less than 1.4 million pounds, and North Carolina third with about 1.3 million pounds. Biological and economic factors blamed for the decline in shad abundance, such as physical changes in the environment, construction of dams, pollution, over-fishing, and natural cycles of abundance, are discussed. Also discussed are methods used for the rehabilitation and management of the fishery, such as artificial propagation, installation of fish-passage facilities at impoundments, and fishing regulations. With our present knowledge, we can manage individual shad populations; but, we probably cannot restore the shad to its former peak of abundance.

The ecology and management of the European grayling Thymallus thymallus (Linnaeus). Interim report

The European grayling, Thymallus thymallus, is a highly under-rated freshwater fish, particularly in the United Kingdom. As such, little scientific research has been conducted on its biology, ecology or specific management plans, in comparison to the related species, salmon, Salmo salar L. and brown trout, Salm.o trutta trutta L. or the nearest relative to T. thymallus, the Arctic grayling, Thymallus arcticus (Walbaum), whose life history has been well documented in view of its high ranking by anglers, as a game fish. However, the importance of sound scientific research cannot be over stressed for this species, which can potentially provide an excellent fishery and source of income in salmonid depauparate rivers. The aim of this report therefore, is to review all available information on the biology, ecology and management of the European grayling, T. thymallus, incorporating findings for T. arcticus to bridge subjects where the literature is scarce, and propose management strategies for T. thymallus in the United Kingdom, bridge subjects where the literature is scarce, and propose management strategies for T. thymallus in the UK.

Conservation and management of marine fishery resources of Kerala State, India

The highly productive fisheries of Kerala, India, are suffering from overexploitation. Use of unsuitable fishing gears that result in a high level of wasteful bycatch and destruction of egg bearing and juvenile fish should be controlled. This paper makes some suggestions for monitoring and conservation of the fisheries in Kerala.

Development, use and management of the Zhoushan fishing ground, China

The Zhoushan fishing area contains the Zhoushan archipelagos, whose population is nearly 1 million, including over 300,000 fishermen. A detailed account is given of the environment and its resources; there are more than 300 species of fish, over 60 species of shrimp, more than 10 species of crab and more than 50 species of algae in the area. The history of fishery development in the area is described, outlining motorization, technology, and education. Various regulations and management activities, implemented in the 1980s, are highlighted.

Biology and Management of Deepwater Snappers of the Hawaiian Archipelago

Commercial and recreational deepwater (100-400 m) bottom-fishing in Hawaii targets a multispecies group of lutjanid snappers. Relatively little is known about the life history of these species. Research in Hawaii and elsewhere in the tropical Pacific suggests that most of the species are slow growing, long lived, and have a relatively high age at sexual maturity. Stock assessment is difficult because of the multispecies nature of the fishery. However, recent analysis of commercial fishery data indicates that some of the species may currently be overexploited. Research is underway to determine the efficacy of management measures such as minimum-size limit changes or seasonal and spatial fishery closures to maintain optimal spawning biomass.

Assessment and Management of Atlantic and Gulf Menhaden Stocks

The organization of coastwide management programs for Atlantic menhaden, Brevoortia tyrannus, and Gulf menhaden, B. patronus, are described. Recent assessments of the status of the Atlantic and Gulf menhaden stocks are summarized. Estimates of population size and fishing mortalities are obtained from virtual population analysis, and are used in determining spawner-recruit relationships, spawning stock ratios, yield-per-recruit, and surplus production. Management issues are addressed in the framework of assessment results.