In the last decade and a half there has been an increased awareness of links with other habitats and assemblages. The importance of geology is dramatically demonstrated by intertidal sites wiped out by land slides (Pearse 1984) and changes in shoreline elevation by earthquakes (Bodin and Klinger 1986). Terrestrial organisms such as rats (Navarrete and Castilla 1993) can be significant predators on intertidal species. Birds will feed on barnacles (Meese 1993) and limpets (Hahn and Denny 1989, Wootton 1992) as well as graze on algae (De Vogelaere 1987). Moreover, bird guano seems to enhance the growth of Prasiola, an alga found in the splash zone (Anderson 1987). When harbor seals hall out on intertidal sites, their waste products bleach algae (De Vogelaere 1991) and the disturbance from their movement affects the local assemblage of species (Boal 1980). Sea otters feed on intertidal mussels, creating patchy distribution patterns (Harrold and Hardin 1986, Van Blaricom 1988). Links with offshore systems include tidepools that act as nursery grounds for subtidal fish (Moring 1986), kelp forests and associated fish that filter larval or intertidal species (Gaines and Roughgarden 1987), and strong upwelling currents that prevent the offshore larvae of intertidal species from returning to the shore (Roughgarden et al. 1988).
Section IV. Temporal Changes