Ichthyofaunal assemblages at 11 surf zone localities along the perimeter of False Bay South Afnca were sampled by seine netting at monthly intervals between July 1991 and J u n e 1993 Sampllng localit~es were selected to encompass as wide a range of physical vanables as possible incorporatlng sheltered, exposed, sandy and mixed-shore habitats, thus providing a colnprehensive assessment of the factors lnfluenclng surf zone fish assemblages Data collected at each site were averaged over the 2 yr p e i~o d in order to highlight the influence of various physical environnlental vanables on the abundance and co~nmunity structure ot these assemblages Athenr~a brevlceps, Liza rlchardsonii and Rhahdosarg~ls gloh~ceps were numeiically domlnant at all sites together providing between 69 and 99%) of the catches Overall catches of juvenile flsh exceeded that ot adult fish, making up almost 53 of the catch Fish abundance (no ind per 100 m') and number of species recorded at each site ranged from 6 to 199 and from 12 to 31 respectivel) Multivdriate analyses Indicated that the deglee of wave exposure the presencc of emergent rock on the shore dnd turbid~ty were responsible for most of the s p a t~a l vanab~lity in abundance and community structure observed Although of lesser importance abundance of detached macrophytes salinity dnd water temperature also played a role in structuring fish assemblages Species specific preferences for varying combinations of these var~ables are responsible for fluctuations in the structure and overall abundance of assemblages in different a r e a

Temporal variations in surf zone fish assemblages and various physical factors at 11 sltes In False Bay, South Africa, were studled over 2 yr from July 1991 to June 1993. Changes in the abundance of fish in the surf and in the relative r a n k~n g of the more frequently occurring species were evldent between years and relative to an earlier study. Of the 9 environmental variables monitored, only water temperature and wind direction varied seasonally. Seasonal fluctuations In fish abundance and numbers of species captured were absent, except at 1 site, where numbers of species recorded v a r~e d seasonally. Physical factors responsible for these fluctuations varied in response to differences In the physical attributes of the different sites, but water temperature, wave height, wind speed and direction and macrophyte abundance were considered to be the most important. When data from all sites were combined, the overall numbers of flsh captured did not appear to vary seasonally. However, seasonal patterns were evident in the abundance of juvenile fish In the surf, and to a lesser extent in the species richness and total number of species captured. Abundance and species richness were highest from mid-summer u p to the beginning of winter, which IS the penod during which most species recruit into the surf zone. We concluded that even when seasonal variations in physical variables such as water temperature are not great, spawning periods of surf zone fish are nevertheless timed to allow most resident and trdnsient O+ juveniles to optimise their use of this habitat K E Y WORDS: Surf zone fish Tcniporal var~ab~lity Environnlental influences . Seasonality -Sandy beach South Africa