Two arrays in inverted echo sounders, one along the equator and the other across the North Equatorial Countercurrent, are analysed together with a wind record from St. Peter and St. Paul rocks. The dominant high frequency feature along the equator is an energetic oscillation with a period of 5.8 days that shows strong coherence with the meridional component of the wind. The sounder at 3¿N 28¿W, on the other hand, shows a high degree of coherence with the zonal component of the wind at a period of 4.5 days. Comparison of these measurements in 1983 with measurements made in 1979 suggest considerable non-stationarity.