There is a battle going on between the swordfish and the shark in the Mediterranean Sea. The experts aren’t sure whether sharks killed by swordfish are due to an accident or a deliberate killing over a fight for territory and/or prey animals. Prey animals are being diminished in the Mediterranean Sea by human overfishing.
Pointing to the fact that swordfish are deliberately targeting sharks is the finding that in all cases the wounds were inflicted by horizontal strikes near the head and gills. This appears to be pretty clear evidence that swordfish are spearing sharks deliberately to kill them.
There is a film of a man pulling the 12 inch tip of a swordfish’s sword out of a dead shark (I can’t find it on YouTube). The killing took place near of the coast of Brega in Libya in April which prompted scientist to think about interactions between swordfish and sharks in the Mediterranean.
It is known that young swordfish use their huge pointed bill to defend themselves against shark attacks and they have occasionally injured fishermen who have targeted them. But in this instance the researchers at the University of Vienna and the Omar Al-Mukhtar University in Libya believe that it is a deliberate killing thrust.
Most fights between swordfish and sharks are unrecorded because they happen in open sea where the killed victim sinks to the bottom of the ocean. Since 2016 there have been six other similar attacks all of which involved juvenile swordfish. There has been an increase in reports of sharks killed by swordfish. This may be due to the fact that everybody carries mobile phones with excellent cameras these days and so are able to publish the images to the Internet creating more reports. An alternative theory is that it is happening more often for the reasons stated above.
P.S. Go to YouTube and you’ll see a lot of videos of successful shark attacks on swordfish and marlin. There appears to be hostility between swordfish and sharks perhaps over fish stocks as mentioned.