Abstract

The shallow waters of the world's coasts comprise a variety of ecosystems such as tidal wetlands, salt marshes, sand flats, rocky coasts, and coral reef flats, and encompass complexes of pelagic and benthic, vegetated and unvegetated habitats. These disparate ecosystems are bound together by one common feature; that the pattern of life for marine organisms, the outcomes of process and the functioning of the ecosystems are irrevocably influenced by the tide. Focusing on the tide highlights a unique component, the intertidal zone – an area that alternates between exposure to the atmosphere and inundation by marine waters. While the tide has diverse influences on the pattern of life and on the processes that regulate ecological function in tidally dominated ecosystems, much of this can be captured in one idea, that the multi-scale predictability of tides provides vital information for the organisms utilising these systems. We explore this idea by considering the dynamics of the nekton assemblages of tidally dominated ecosystems, the roles that nekton play in the functioning of those systems, and how these dynamics are fundamentally influenced by the differential responses of nekton and their prey to the predictability of tides. Further, we discuss the nature of the information tides provide to biota, the trade-offs inherent in utilising tidally available resources, and strategies employed by biota to take advantage of the tidal information and the need for strategic trade-offs.