Total number of GCs for the UDG sample (black open circles) and those belonging to the UDGvD15 selection criteria (indigo open circles) as a function of the galaxy stellar mass. The number of GCs is shown to steadily increase with total stellar mass for the full sample of UDGs. The trend continues as the stellar mass increase to massive early-type galaxies, as can be seen using the GC counts obtained from the HST ACS Fornax cluster survey (Liu et al. 2019) (blue open circles). The galaxies in the UDGvD15 sample extend higher at each stellar mass than the galaxies in the non-UDGvD15 sample with the exception of the two most massive bins which contain no galaxies from the UDGvD15 sample.