Recent research has shown cuttlefish, octopuses and squids are thriving. The three cephalopods have increased in number compared with many other species of fish that are declining.
According to Zoë Doubleday, lead author of the study and marine ecologist from the University of Adelaide in Australia, over the last 60 years, the number of cephalopods has substantially increased. Plus, it seems that there is something in the marine environment that helps these animals.
Dr. Doubleday and her team gathered all the information regarding the population numbers of cephalopods from 1953 to 2013. They also used the data from the historical catch rates for 35 cephalopod species, including the common cuttlefish, the giant Pacific octopus, and the Japanese flying squid.
All these 35 species live in various marine ecosystems throughout the world such as Madagascar, Morocco, United States, Australia, and many other countries. After they had looked at the data, they established that every species is thriving. Plus, she was amazed at how consistent these increases were among the cuttlefish, octopuses, and squids, including the creatures that live in tide pools and the species that live in the open seas.
According to a World Wildlife Fund report from 2015, around 1,200 marine vertebrate species dropped off in numbers from 1970 to 2012, including fish like tunas and mackerels. John Tanzer, Director of the W.W.F. International Marine Program, said that this situation is not to be taken lightly because the loss of these marine animals will affect the entire water ecosystem that supports life on Earth.
Still, invertebrates, such as cephalopods, are doing just fine. Dr. Doubleday and her team are trying now to determine why cephalopods are thriving whereas many other marine animals are dying. Until now, she believes that overfishing might be a possible cause. It means that overfishing might reduce the number of fish that hunt cuttlefish, octopuses, and squids.
But if they manage to find the answer, we will better understand what is the real impact of human activities on the ocean. After so many bad news regarding marine life, it’s nice to hear that there are still some species that thrive in the ocean. We can only be glad for octopuses and squids and hope that many other species of marine animals will increase in numbers.