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The concept that ocean fronts are important features in oceanic biology has a long history, as noted by the quotations cited above. The example of a functional understanding of fronts provided by a common fisherman is an example of scientific knowledge lagging behind common knowledge (see Franklin, 1786). The modern situation has seen major advances in our understanding of frontal dynamics and the basic processes that influence biota in fronts. There are still many questions, however, concerning the nature of biological response to fronts. In fact, just as the physical oceanographer still asks whether the Gulf Stream front is an area of strong mixing or a barrier to exchange (Bower et al., 1985), the biological response can be thought of as enrichment (Murray and Hjort, 1912; Hitchcock, 1988; McClain et al., 1988) or as a region of stress and death (Murray and Hjort, 1912; Dutkiewicz et al., 1993). In relationship to Folger’s observation on whales, it is possible to say that many large free-swimming animals seek out fronts for forage and migration but in a preferential way, i.e., they seek out definite subdomains of the frontal zone environment. The nature of fisheries, regrettably, makes it very difficult to test these hypotheses because of inadequate data and lack of control samples; fishermen do not fish where they expect to find no prey (Podestá et al., 1993). In modem fisheries where fishing is often guided by the same satellite remote sensing charts of frontal locations that are available to scientists, the control samples are indeed rare.