Crustacean Facts and Favorites in North Sulawesi
Divers and especially macro photographers are often amazed by the abundance and diverse range of crustaceans which can be found in North Sulawesi. At some of our muck diving sites the number of shrimps, crabs and other crustacean species can almost equate to the number of fish species! Did you know that crustaceans are second only to mollusks in terms of their diversity in the marine realm, with well over 30,000 species described to date and many, many more that have not yet even been named by science.
Most of us recognize crabs, shrimps and lobsters as crustaceans but this diverse group also encompasses isopods, amphipods and even barnacles!
All crustaceans are in the Phylum Arthropoda; along with their terrestrial cousins the insects, spiders, centipedes and millipedes, they all have an external skeleton (known as an “exoskeleton”), a segmented body and jointed legs. All crustaceans have two pairs of antennae at some point in their life cycle, and those that are most familiar to us are generally in the order Decapoda with five pairs of legs (this includes the crabs, shrimps and lobsters).
Most crustaceans are active at night, so for those who are keen to spot as many species as possible, we highly recommend making some night dives with us during your stay. Crustaceans which are found on “hosts” such as anemones, sea whips or bubble corals can be spotted through the day and we see many different species on almost every dive.
Here are a few of our favorite and most intriguing crustaceans which can be found in North Sulawesi…
The mantis shrimp is one of the most famous crustaceans in the world due to its phenomenal vision which is the most advanced in the entire animal kingdom. The “smashing” species’ (such as the peacock mantis, pictured here), are also known to deliver blows to their prey which are delivered with the same force as a 9 caliber bullet being fired from a pistol!
One of the most sought after crustaceans which many divers want to see is the stunning harlequin shrimp (Hymenocera picta). There is no denying this crustaceans beauty but did you know that they are actually ferocious carnivores? Harlequin shrimp feed mainly on blue sea stars. Living in a burrow and working in pairs they will cut off an arm from the sea star with their claws. Together they will then drag the severed arm back to their burrow to feast on!
Did you know that the Emperor Shrimp can often be found “hitchhiking” from feeding ground to feeding ground onboard the back of nudibranch? In return for the free ride, they will clean parasites from the nudibranch along the way. One of their favorite nudibranch to use for “transport” is the ceratosoma nudibranch which is a type of T-bar nudibranch and can be seen in the title image above.
Boxers or Pom-Poms?
Did you know that the names Boxer Crab and Pom Pom Crab relate to the same species? The scientific name is Lybia tesselata and their common name comes from the two small stinging anemones which the crab “wears” on it’s claws for protection. While some people say they resemble boxing gloves others say they are more akin to a cheerleaders’ pom-poms – which is the best fit? You decide!
Why not enhance your time in Indonesia and join us for a Passport to Paradise while you are here? Discover three of North Sulawesi’s most notable diving areas (and increase your crustacean sightings) in one incredible trip: Bunaken -> Bangka -> Lembeh. Discover epic walls in the Bunaken Marine Park, kaleidoscopic reefs surrounding Bangka Island and the world’s best muck diving in the Lembeh Strait. With seamless boat diving transfers from resort to resort there’s no wasted transfer days and no gear drying or packing – just dive your way around North Sulawesi!
If you’d like to make a reservation, or for more information please contact us on: [email protected] – we look forward to diving North Sulawesi with you soon!