Introduction

Menhaden are uncommon as a food fish, and thus are unfamiliar to the general public. There are two species of menhaden off the US coast, each of which supports a separate US menhaden fishery, the Atlantic coast fishery (Brevoortia tyrannus), and the Gulf of Mexico fishery (B. patronus). Together, they comprise one of the largest (by weight) commercial fisheries in the US (Henry, 1971; Rothschild, 1983). Prior to World War II, Atlantic menhaden dominated the total catch. Between World War II and 1962, larger and more efficient vessels led to a steady increase in Gulf landings (Vaughan et al., 1988). By 1963 Gulf menhaden landings exceeded those from the Atlantic (Henry, 1971).

The menhaden processing industry produces fish meal, fish oil, and fish solubles. During 1980, for example, more than 75 percent of the fish meal produced was used domestically, and over 90 percent of the fish oil was exported, primarily to European markets (Hu et al., 1983). Menhaden, therefore, are of value not only to the US economy and fishing industry, but also play a role in the international marketplace. Present-day development of new products and uses of menhaden by-products, such as medicinal uses of fish oil and surimi (minced fish), is bringing the menhaden fishery into a new prominence which will directly benefit the diet and health of citizens in the US and elsewhere.

* The author was a Visiting Scientist with the Environmental and Societal Impacts Group, National Center for Atmospheric Research, at the time this research was carried out.

This chapter focuses on historical changes in Atlantic menhaden. Interannual and interdecadal fluctuations in commercial fish catches are well known, although their causes are often poorly understood. Recruitment, or year-class strength, can be influenced by year-to-year regional and global-scale environmental changes, as well as by other population responses and differences attributable to stock density (Cushing, 1974). The understanding of the relationship between the early life history, juvenile and adult stages of menhaden and their environmental settings is crucial in assessing what impact a global climate change may have on their distributions and abundance (Fig. 6.1). These will affect the fisheries, and therefore society in general. Based on analogies drawn from past societal actions, lessons can be drawn and used as warnings or guidelines for the future.

Climate Variability and Change and its influence on estuarine/oceanographic processes

Climate Variability and Change and its influence on estuarine/oceanographic processes

Life History of Menhaden

Survivorship

Anthropogenic Effects- Recruitment (Transport)

Pollution (Disease) Age, Size, Growth

Habitat Degradation Migration Patterns

Survivorship

Anthropogenic Effects- Recruitment (Transport)

Pollution (Disease) Age, Size, Growth

Habitat Degradation Migration Patterns

Fig. 6.1 Influencing effects and interrelationships of climate variability and change on menhaden life history, fishery and industry, and on society.
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