This picture is called "bird vs rabbit", but there is no much in therms of "versus", the poor rabbit is adversary in the same sense a Big Mac is an opponent for me. The bird actually is Grey Heron (Ardea cinerea) and the rabbit is most likely to be pet dwarf rabbit (at least in my opinion, we can judge from the shape of ears, head and the colour, also it seem too dark for young Hare). It looks bizarre and abnormal for us, but the Herons usually will eat all small enough animals they can catch.
In this video is shown the St James's park in London, where a pelican swallows alive pigeon. The moment was caught on camera by the photographer Cathal McNaughton. The pelicans usually eat fish, but if they are starved, they will eat almost anything they can catch. There are known cases where they have eaten ducklings for example.
All is OK, all it's natural, but the last one is already excessive.
Sources: Daily Mail, BBC