I'd call this Work, and certainly Art
But that's just because my eyes behold it. The spiders who leave silk on it, and the tiny dasyurids who leave droppings smaller than that of mice, don't think of art at all. It is a vertical surface that leads to something as far as the dasyurids are concerned, and to the spiders, it's another terrain. To people who don't appreciate Art, it is a detail of the side of a galvanised steel garbage bin.