This photo was posted on the Vancouver Vice Superintendent Michelle Davey’s Twitter feed.
On Snopes.com they are asking for a source, so the veracity of this image is unverified. However, it does not matter if this is real, staged, edited or manipulated. Here’s an article refuting the claim.
The image exists, and that alone is enough for the idea of pigeons making a nest out of used needles is thus legitimate.