SYMBIOTIC RELATIONSHIP

SYMBIOTIC RELATIONSHIP

If you're not familiar with the term ‘symbiosis’, it literally means ‘living together’ and refers to the special relationship that different species form with each other. As you can imagine, the coral reef is full of symbiotic relationships, some of which are beneficial to both species, some of which are harmless and some of which, like parasites, are definitely harmful. That's why I was so happy when I spotted these creatures on one of our dives at Bacan Island, South Halmahera!
They are a pair of Hypselodoris tryoni (nudibranchs), each with a Periclimenes imperator (emperor shrimp) living on them.
This colourful shrimp lives as a hitchhiker and cleaner on some nudibranchs and some sea cucumber species. The shrimp gets protection and extra food, and the host benefits from the free removal of parasites (and probably the occasional tickle...) - everyone is happy! This is just one form of symbiosis called ‘mutualism’ because both species benefit.

We discovered this interesting ‘duo’ during a dive at the dive site Black Sand - Bacan Island, Indonesia - by the way, I ‘LOVE’ nudibranchs!
I am always fascinated by such interesting encounters under water.

Bacan Island, Indonesia, August 2024
Olympus OM-D E-M1 Mark III, 60er Makro M.Zuiko 1:2,8