Fortunately for you, I've made a map!

In case you can't see it, you're basically about 85 feet away from the harpies. Where the sun is at right now, the mountain is shadowing the tree, allowing Shortfang to see them despite his light sensitivity. Additionally light grey rocks near you are cliffs that are about ten feet above you, however the dark rocks are impassable terrain (too rocky, sheer cliffs, etc). Of course, might not
entirely be an issue for you. The lighter color rocks indicate a twenty foot drop to mostly traversal terrain, however beyond that is steep cliffs aka you will fall to your death.