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We present the results of a survey for intervening MgII absorbers in theredshift range z $\simeq$2-6 in the foreground of four high redshift quasarspectra, 5.79$\le z_{em}\le$6.133, obtained with the ESO VLT X-shooter. Weidentify 24 absorbers at $\ge 5\sigma$ significance in the equivalent widthrange 0.117$\le W_{2796}\le 3.655\unicode{xC5}$ with the highest redshiftabsorber at $z=4.89031\pm4\times10^{-5}$. For weak($W_{2796}<0.3\unicode{xC5}$) systems, we measure an incidence rate$dN/dz$=1.35$\pm$0.58 at <z>=2.34 and find that it almost doubles to$dN/dz$=2.58$\pm$0.67 by <z>=4.81. Weak absorbers exceeds the number expectedfrom an exponential fit to stronger systems ($W_{2796}>0.3\unicode{xC5}$). Wefind that there must be significant evolution in the absorption halo propertiesof MgII absorbers with $W_{2796} >0.1\unicode{xC5}$ by <z>=4.77 and/or thatthey are associated with galaxies with luminosities beyond the limits of thecurrent luminosity function at z $\sim$5. We find that the incidence rate ofstrong MgII absorbers ($W_{2796}>1.0\unicode{xC5}$) can be explained if theyare associated with galaxies with $L\ge0.29L_{\ast}$ and/or their coveringfraction increases. If they continue to only be associated with galaxies with$L\ge0.50L_{\ast}$ then their physical cross section ($\sigma_{phys}$)increases from 0.015 Mpc$^2$ at z=2.3 to 0.041 Mpc$^2$ at <z>=4.77. We measure$\Omega_{MgII}$=2.1$^{+6.3}_{-0.6}\times10^{-8}$,1.9$^{+2.9}_{-0.2}\times10^{-8}$, 3.9$^{+7.1}_{-2.4}\times10^{-7}$ at <z>=2.48,3.41, 4.77, respectively. At <z>=4.77, $\Omega_{MgII}$ exceeds the valueexpected from $\Omega_{HI}$ estimated from the global metallicity of DLAs at z$\simeq$4.85 by a factor of $\sim$44 suggesting that either MgII absorberstrace both ionised and neutral gas and/or are more metal rich than the averageDLA at this redshift.

The comoving mass density of MgII from $z\sim2$ to $5.5$