In 2014, a team of scientists discovered a giant squid with a wingspan of 100 metres in the Gulf of Mexico.
They named it Sebastian, after a Portuguese explorer who explored it in the 15th century.
The creature has now grown up to the length of a 10-metre-long bus, and has begun to use its fins as a means of propulsion.
The team described Sebastian’s growth in an article in the journal Nature.
They say that in the next few years, Sebastian may become the world’s largest squid, possibly weighing as much as 1,000 tonnes.
The researchers said the creature was about 1.5 metres long, and was covered in a gelatinous mucus.
The specimen was collected in 2014, and then returned to its home in the ocean to be analysed.
The squid was then transferred to a research vessel, and researchers released it into the water.
The vessel found that it was growing by around 10% a year, and in 2016 it weighed in at around 1,500 tonnes.
Sebastian was later tracked and filmed by scientists at the University of Cambridge.
Sebastian’s new home has since been moved into a different ocean, which will allow researchers to study the creature more closely.