We examine the isotherm displacement fine structure spectra obtained from expendable bathythermograph casts at different places within a Gulf Stream ring. If N is the Brunt-V¿is¿l¿ frequency and N0=1 cph, we find that spectra from different depths groups together fairly well with (N/Nd0) scaling and roll off as ~k-2. If &zgr; is the isotherm displacement, scaled displacement variances (N/N0)n ⟨&zgr;2⟩(n=0,1,2: N0=1 cph) formed from the wave number decade 0.04≤k≤0.4 cpm are regressed upon the vertical mesoscale shear. It is found that when n=0 or 1, the scaled variance and the shear are negatively correlated, but the potential energy variance (n=2) and the shear are uncorrelated. An explanation for the correlation when n=0 is offered by examining the effect which a vertically sheared flow has upon internal waves and upon a patch of mixed fluid.