So there are a lot of dino who can gather berrys but i reccomend taming mammoth'bronto or ankylo mammoth can gather lots of berrys and they can also gather woods bronto can gather much more berrys than mammoth but you need to be high level to craft its saddle and why anky is also there because they can also gather lots of berrys i tried it i try to gather 3 plants and they get lots of berrys in just 3 plants anky can also gather lots of obsidian and metal and maybe doe can gather berrys up this if helpfull