An array of seven inverted echo sounders was moored along and across the Kuroshio in the East China Sea for more than one year. The data from this array show evidence of energetic meanders with periods of 7, 11, and 16 days. The respective phase velocities of these meanders are 28, 20, and 17 km day Ϫ1 downstream. The 7-and 16-day waves are intermittent, but the 11-day waves are present throughout the deployment. The instability responsible for these waves is investigated with a spectral numerical model applied to a background state representing the Kuroshio in this region. The fastest-growing instability from the model has e-folding growth time of 2 days, period of 12 days, and phase velocity of 18 km day Ϫ1 downstream. It appears to be a close representation of the 11-day wave seen in the observational data. Such a model has been previously used to represent meanders in the Gulf Stream at similar latitudes off the east coast of the United States. The Kuroshio meanders have approximately half the phase velocity and twice the period of the Gulf Stream meanders. To investigate the reasons for these differences, the flow and topography of the model background state were varied. The slower phase velocity and longer period of the Kuroshio meanders appear to be consequences of the deeper shelf and lower transport, with a modifying effect due to the difference in cross-shelf positioning of the current core (more over-the-shelf in the case of the Kuroshio).

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Quantified estimates of southern rock lobster (Jasus edwardii) puerulus settlement have been undertaken in the Southern Zone fishery of South Australia since the early 1990s. An analysis of mean monthly puerulus settlement indices from 1995 to 2007 in three monitoring sites revealed a strong seasonal correlation (r > 0.94 between sites) in settlement patterns. Settlement was highest during the winter months of June, July and August with peak settlement in all sites occurring in July. A reduced secondary settlement occurred during February and March. Seasonal trends were correlated with monthly wind stress and direction data in order to investigate possible environmental drivers of settlement. Using monthly averages of wind stress, it was hypothesized that strong alongshore wind-stress anomalies (ASWSA) prior to peak settlement would influence puerulus indices. Maximum ASWSA over the December-May period prior to maximum settlement was therefore examined. The results showed significant correlations (P < 0.1, r = 0.51-0.90) between wind stress and puerulus settlement in all but one site. We suggest that storm events, in combination with onshore surface drift during the period of settlement, are the principal physical oceanographic mechanisms influencing settlement patterns within the Southern Zone rock lobster fishery of South Australia.

The seasonally averaged wind stress of the Great Australian Bight (GAB) during the austral winter is directed to the east along the shelf and results in downwelling that extends to depths of 250 m. This downwelling is enhanced in the eastern GAB through the outflow of cold saline water formed in the broad shallow regions of the GAB and gulfs. During the austral summer, the averaged wind stress field of the GAB is anticyclonic with upwelling favorable winds along much of the coastline. In general however, significant slope upwelling is only observed in the eastern and western GAB where the shelf is narrow. Upwelling there provides nutrients to support the planktic and pelagic communities and the observed distribution of benthic invertebrate communities that lead to the formation of neritic carbonate sediments. At the shelf break of the central GAB where the shelf is very wide, the observed cross‐shelf distributions of temperature, salinity, and sediments indicate that downwelling occurs year round. The implied lack of nutrients is argued to explain the smaller communities of invertebrates found at the shelf edge (100–250 m) in these areas. A previous numerical study is cited to show that summer downwelling very likely results from a convergence of the deep ocean and poleward Sverdrup transports. The unique aspect of this integrated oceanographic‐sedimentological investigation is to tie outcomes of that numerical study with extant observations and benthic habitat to provide a consistent picture of how cross‐shelf exchange regulates water properties and benthos in the GAB.

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