Street Art Sculpture or Pigeon Detterent?

On my way into one of the overhead 'U-bahn' metro stations in Berlin I couldn't help but to register this colourful collection of decorative, wall mounted shapes. I remain unsure as to whether they were part of the station design or whether one dilligent individual has taken time and exerted effort in creating and erecting said pieces. If anybody out there should know any better, I'd be happy to hear about it.