Skimmer Leaf Guard
In the fall with leafs falling the skimmers can get clogged with leafs if you leave your pool open all year. Storms can blow leafs off of treas and clog skimmers and starve pumps of water at times when you most need the pump running and possibly freeze protection.
There are commercial products and DIY skimmer leaf barriers.
Commercial Products
DIY
Skimmer Leaf Trap
Skimmer Leaf Trap on Instructables is built with PVC pipe and a net to hang over the skimmer opening.