This astonishing image from the Marine Photobank shows a diver working to free a sperm whale from a tangle of fishing gear.
It was taken in 1981 by Alberto Romeo when he and a team of divers from the the Gruppo Ricercatori ed Operatori Subacquei (an underwater association that defends and photographs marine wildlife) came across a sperm whale tangled in a drift net in the Mediterranean Sea.
The team entered the water on a seemingly impossible rescue mission. The whale had massive head injuries but the team proceeded to do all they could to save it. Romeo said:
“After we cut away the net-trap near the tail he began to swim away. After a few meters and with only a little piece of net still attached to his tail he turned to us, to say ‘thank you.”