Dave Senior,
I think you are overlooking the most obvious translation of the word Etrange which is "unknown".
I think you probably have a point here. Thatīs why I would like to see the original phrase.
Nevertheless, I have my doubts if an expert couldnīt have a good idea of the shark species by inspecting the bites. There are not many shark species making a life at high seas, and the most dangerous shark there is the oceanic whitetip, known to attack wrecked tripulations of ships and aeroplanes crashes.