Mon 19 Apr 21
Anyone reluctant about emerging from lockdown and having to start mixing with others should spare a thought for the Caribbean reef octopus – as they hate being sociable claims a new study.
Whereas octopuses are generally known for being “asocial” – neither avoiding nor seeking company – new research from the University of Essex shows the Caribbean reef octopus, Octopus briareus, actively avoids being with others.
The research, published in the Marine Biology journal, focused on the octopus population living in the tropical landlocked lake Sweetings Pond on the island of Eleuthera in the Bahamas. Its unusual environment is shrouded in local folklore and home to many distinctive species such as seahorses, octopuses and giant crabs.
Led by Duncan O’Brien, the research involved setting up artificial dens in different cluster numbers to see if the octopuses preferred being together or apart.
“Our findings showed that this population of octopus goes out of its way to avoid others, trying to find hidey-holes with less chances for neighbours. They are true self-isolators,” explained Duncan, who carried out the study during his Masters degree.
Due to the lake’s environment, there are no octopus predators and its geology prevents the adults moving to the wider ocean, which has resulted in a higher density of octopuses than other coastal environments.
“We initially thought that the high population density would result in the octopus population being more sociable,” added Duncan. “But, in fact, we saw the opposite, as the octopuses preferred to rest by themselves and were more frequently found in isolated artificial dens than grouped dens.
“Octopuses are generally thought of as being ‘asocial’ and not being attracted nor repelled by members of its own species, so such antisocial behaviour was unexpected. One theory is they are trying to avoid conflict with other octopuses, but this would need further research.”
The Centre for Ocean Research and Education facilitated the project which meant Bahamian students of all ages helped with the data collection process.
“Sweetings Pond is shrouded in folklore to such an extent that local Bahamians often avoid it for fear of the ‘kraken’ or giant eel that lives in its ‘bottomless’ waters,” added Duncan. “By taking part in the data collection, a number of students now actively promote the protection of this unique site right on their doorstep.”