We present a survey of rapid reductions in electron flux within the Martian upper atmosphere and induced magnetosphere for one full Martian year (January 2010 to April 2012). These observations are made with the Mars Express (MEX) Analyzer of Space Plasmas and Energetic Atoms Electron Spectrometer (ASPERA-3 ELS) instrument, and are referred to as electron holes. The electron holes occur across a wide range of energies and are a common occurrence within the Martian induced magnetosphere. Analysis of the electron hole locations shows evidence of increased event occurrence over locations of strong crustal magnetic fields. Such events are mostly distributed across altitudes where the crustal magnetic fields can still play an important role in the interaction of the solar wind with the Martian plasma system. Since the Mars plasma environment interaction with the solar wind is primarily with its ionosphere, understanding the presence of these electron holes could give a deeper insight into the temporal evolution of the Martian atmosphere.