This is a photograph of what appears to be an insect’s nest. It may be a nest of something like a hornet or something similar.
This photograph can inspire a number of poetry ideas. One idea would be the ideas of protection and shelter. This nest presumably provides both, and those ideas could be used in a poem. For example, a poet could write about finding shelter in the rain or about the idea of finding a place to feel protected.
Another idea that could be inspired by this photograph is the idea of construction. This nest was constructed, and the idea of construction could be used in a poem. Since the nest was built using natural materials (all be it, on a manmade wall) a poet might decide to write about a structure built with natural materials. This could range from the idea of a temporary shelter in the woods, to a modern home built with natural materials incorporated.
Another idea that could be inspired by this photograph is the idea of vulnerability. This nest is on a wall. It could be easily damaged by rain, animals or human beings. The idea of vulnerability could be used in a poem. For example, using the ideas of protection, shelter and construction from above combined, a poet could write about someone building a shelter in the woods, for example when they are lost. The poem could describe the construction of the shelter for the purpose of protection and have allusions to the vulnerability that the person has and feels.