Situated in the Southern Indian Ocean, the Kerguelen plateau is known for intense phytoplankton blooms due to local iron enrichment. Any change in mixed layer depth (MLD) could impact this large marine ecosystem. Using 17-years of observational data, obtained mostly with animal-borne sensors and Argo floats, we investigate the distribution and temporal trends in MLD. We use a principal components analysis through conditional expectation (PACE) to reconstruct the MLD distribution from sparse in situ data. The accuracy of the PACE method is evaluated using a reanalysis product, and deemed suitable in the region. We identify a marked difference between a deep MLD region onto and west of the plateau surrounded by a shallower MLD region. The eastern boundary between the two regions matches the eastern shelf break, found west of the Polar Front. Temporal trends in MLD are estimated for the years 2007-2023. We find a general shoaling in winter (-1.75 m/year), contrasting with a deepening in summer (+0.8 m/year). Overall, the seasonal amplitude of MLD is reduced. Potential factors responsible for the observed trends such as surface warming and increasing wind stress are discussed as well as their possible impact on primary productivity.