Bays and Estuaries

Estuaries are among the most productive areas on earth, and fish biomass in these habitats ranks with that of the marine regions of upwelling, coral reefs, and kelp beds. This chapter characterizes California bay-estuarine fish assemblages from two broad perspectives: latitudinal distribution patterns, and major ecological features. The coastline from Humboldt Bay in northern California to Laguna de Ojo Liebre in central Baja California spans about 11° of latitude and crosses biogeographic boundaries and environmental gradients, especially of temperature and rainfall. This perspective can be divided into two components: species-area relationships, and classification based on salt tolerance and life-history pattern, which relate generally to the ecological classification of the entire California marine fish fauna. The overarching ecological features of diversity, productivity, seasonality, inter-annual variability, and nursery function are important in portraying and understanding bay-estuarine fish ecology.