Cuttlefish eat less for lunch if their favourite food is on the menu later, research finds

Cuttlefish will eat less during the day if their favourite meal is on offer in the evening, according to new research.  

Scientists found that the animals would limit the number of crabs they consumed if they expected to eat shrimp —​ their preferred food — later on.

This demonstrates “a complex cognitive ability”, researchers said. 

Pauline Billard, an author of the study published in Biology Letters, said it only took the fish a few days to learn whether or not they could expect shrimp later that day, depending on how they were being fed during the experiment. 

“It was surprising how quickly the cuttlefish adapted their eating behaviour,” she said. 

“This is a very complex behaviour and is only possible because they have a sophisticated brain,” according to Ms Billard, a PhD student at the University of Cambridge’s Department of Psychology.

Researchers looked at 29 European common cuttlefish, giving them crab and shrimp five times a day for five days and finding they all preferred the latter.

In further experiments, they found cuttlefish who were given shrimp every evening would eat fewer crabs during the day compared to another group fed their favourite meal at random, who instead became more opportunistic. 

In another test, cuttlefish were given shrimp every other evening and “adopted a flexible foraging strategy, adjusting the consumption of their less preferred prey in response to the upcoming availability of the preferred prey”, 

The marine creatures have a large central nervous system — similar to humans and other vertebrate animals — which helps them remember past events and change behaviour based on their expectations, the researchers said. 

Nicola Clayton, a University of Cambridge professor who led the study, said: “This flexible foraging strategy shows that cuttlefish can adapt quickly to changes in their environment using previous experience.

“This discovery could provide a valuable insight into the evolutionary origins of such complex cognitive ability.”

Press Association contributed to this report