A fairly lousy photo I'm afraid, but it shows quite clearly a pure black rabbit in a garden, along with a more ordinarily coloured version in the foreground. These are both 'wild' rabbits, so I can only presume that the black one is an escaped pet. Apparently it's been around for a while and seems quite happy.

Could it inter-breed with the others, and if so what colour would its progeny be? A quick web search suggests that yes they can inter-breed, depending on the exact species of domestic rabbit. I imagine pet rabbits escape quite often so it's perhaps surprising that we don't see more variation in the colours of rabbits in the wild. But maybe the swift turnover of rabbit populations soon engulfs these oddities and loses their DNA in the wider pool.