A View from the Ocean

Abstract

Migration is defined as a coming and a going with the seasons on a regular basis and a distinction is made between local and more extensive movements in terms of fish-body lengths (10 3 Land 10 5 L, respectively), the former being likely to be associated with scalar and the latter with vector quantities. It is suggested that cZue and cue be used, relative to migration, in the sense of information as to where and when respectively. The open ocean is considered as the sea area where oceanic currents are stronger than tidal currents and the importance to migration of the main circulatory features of the ocean, at different scales, is discussed. Boundaries (at the surface, between water masses, and near the bottom) are identified as sites where migrants might obtain directional clues. Negative attitudes towards the publication of primary data are considered as a serious hindrance towards an advance in our knowledge and understanding of problems of homing and migration. While there is reason for concern over data that are known to have been collected, there is the further problem over data which may have been collected and about which nothing is known. There could be a need for a focal point for the exchange of information and the deposition of archival material.