@Skarp, sorry it took so long but I think I’ve found the solution. I’m using an iPad so I have no idea how it would work or look on other platforms, hopefully similar.
Some shapes on map are flat others are raised. Dino’s will often go for shapes of either kind. You can tell if you can hit it or not by whether the center circle is white or shaded. There may be areu off each at the same time. You can hit the white areas. If your aim is not that good you can wait for it in a gap or on the other side of the obstacles. On others it will walk on top and the circle stays white. Sometimes you can get the dino to go away from the shape of you tag it while on the way, others it keeps trying to hide.
Please let me know if this was helpful or not and if you get different results.