It is very common to encounter medium and giant Atlantic bluefin tuna in the Strait of Gibraltar during the summer season. This predatory species generally migrates to the Mediterranean area in the summer to reproduce and their size can range from 100-800 lbs (50-400 kg). Bluefin tuna usually travel in medium to large size schools and enjoy diving deep. They are also considered one of the fastest fish species on the planet as they can travel at a blistering speed of over 70 km/h.