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We study the Globular Cluster (GC) system of the nearby elliptical galaxy M87using the newly available dataset with accurate kinematics (Strader etal.2011). We find evidence for three distinct sub-populations of GCs in termsof colours, kinematics and radial profiles. We show that a decomposition intothree populations (blue, intermediate and red GCs) is statistically preferredto one with two or four populations, and relate them to the stellar profile. Weexploit the sub-populations to derive dynamical constraints on the mass andDark Matter (DM) content of M87 out to $\sim100$ kpc. We use a class of globalmass-estimators (from Paper I), obtaining mass measurements at differentlocations. M87's DM fraction changes from $\approx$0.2 at the starlight'seffective radius (6 kpc) to $\approx$0.95 at the distance probed by the mostextended, blue GCs (135 kpc). We supplement this with \textit{virialdecompositions}, exploiting the dynamical model to produce a separation intomultiple components. These yield the luminous mass as $5.5^{+1.5}_{-2.0}\times10^{11}M_\odot$ and the DM within 135 kpc as $8.0^{+1.0}_{-4.0}\times10^{12}M_\odot.$ The inner DM density behaves as $\rho \sim r^{-\gamma}$ with$\gamma\approx 1.6$. This is steeper than the cosmologically preferred cusp$\rho \sim r^{-1},$ providing evidence of DM contraction. Finally, we combinethe GC separation into three sub-populations and the Jeans equations, obtaininginformation on the orbits of the GC system. The centrally concentrated red GCsexhibit tangential anisotropy, consistent with radial-orbit depletion by tidalshredding. The most extended blue GCs have an isotropic velocity dispersiontensor in the central parts, which becomes more tangential moving outwards,consistent with adiabatic contraction of the DM halo.

Dynamical Models of Elliptical Galaxies -- II. M87 and its Globular Clusters