Most divers in Asia are familiar with mantis shrimp, especially the colourful and comical rainbow mantis shrimp (Odontodactylus scyllarus) regularly spotted on reefs throughout the region.

Already considered amazing for their ability to spear, stab or pulverize prey at blindingly rapid speed (plus a whole host of other unusual talents), some mantis shrimp, or stomatopods as they’re known, also have the unique capability of being able to see circular polarized light (CPL).

CPL differs from linear polarized light (which is the type of light your Oakleys or Ray Bans create to pamper your eyes), as photons travel in parallel, rotating wavelengths instead of up-and-down wavelengths.

No other organism on earth can see this form of light…at least as far as anyone knows.

What practical purpose does this serve? No one’s certain, but it’s very cool nonetheless. Read more here.

FiNS Associate Editor Tony Wu has just posted a story about his recent trip to swim with adorable Australian sea lions in Western Australia. Read more here. 

Following our recent post about the unusual frogfish photographed in Ambon Bay by Maluku Divers, we’ve received interesting feedback from a number of people.

Among the suggestions early on was the possibility that the UFRO (Unidentified FROgfish) could be a Antennatus linearis, which was first described in 2001 by Randall and Holcom. This potential ID was partially based on the lack of a visible esca (the frogfish’s bait).

After more people around the world weighed in, we began to consider another possibility… Read more…

Check out this video of a very large, rare, six-gill shark (most sharks have five gills) taken by researchers in a submarine 1000 metres down in Hawaiian waters. Almost as interesting as the shark is the excited chatter of the researchers.

During a recent dive at Laha in Ambon Bay, divemaster Toby Fadirsyair and Maluku Divers’ owner Buck Randolph found this unusual fish. Toby, who has been diving the region for over 18 years, had previously only seen this fish once before, 15 years ago. The specimen pictured here is one of a pair and is about 10cm long.

Unable to identify the frogfish, Maluku Divers enlisted help from photographers Beth and Shaun Tierney, who were equally fascinated, but unable to ID the critter.

Maluku Divers has sent these images to fish experts around the world, and is seeking your help to identify this frogfish. If you’ve seen this fish before and/ or can help identify it, please contact Maluku Divers

Something large and curious made a guest appearance 900 metres down on an oil and gas exploration site last year. Take a look at this video to find out what it was. (Source: Appin Scientific Ltd)

Did you know that some coral reef fish establish a pecking order based on size, and use the threat of punishment to keep other fish in line?

Researchers at James Cook University recently published a study based on analysis of coral goby behaviour at Lizard Island in the Great Barrier Reef. Only the largest male and female gobies in a particular group mate, so gobies living together establish a queue according to size, and wait their turn to reproduce.

There appears to be approximately a 5% difference in size between any particular fish and the one immediately above or below it in the queue. If the size difference drops below this, there may be an ensuing challenge by the smaller fish to jump the queue and move ahead. But if it fails, the larger one may punish the upstart youngster by driving it out of the group…which in coral reef terms, probably means death.

Read more about this fascinating study here

Here’s something interesting. Take a few seconds to look at this nudibranch (Chromodoris coi), a type which is quite common on our reefs. We took this photo recently during the Tioman Mega Dive event. See something unusual?

Did you know that clownfish talk to each other? Well, perhaps not exactly “talk” like Nemo in the movie, but they make sounds to communicate among themselves, and maybe to other marine life too. This was demonstrated recently by Eric Parmentier at the University of Liege in Belgium, who is a fish-behaviour specialist.

According to his research, published in the journal Science, Eric and his colleagues determined that clownfish use their jaws to make clicking and knocking sounds…essentially snapping their jaws shut, producing a sound similar to the chattering our teeth make when we shiver.

Perhaps clownfish can’t engage in deep discussions about the meaning of life, but it seems that they’re much more talkative than most of us imagined.

Here’s a sample of clownfish chatter:

Here’s an interesting update we received from FiNS Magazine Associate Editors Andrea and Antonella Ferrari:

Recent research by cephalopod specialist Mark Norman has shown that the colourful displays put on by flamboyant cuttlefish (Metasepia pfefferi) are for a specific purpose…to warn would-be predators of potential danger. In the case of this cryptic cuttlefish, it’s not the bite which is venomous (which is the case for blue-ring octopuses), but it’s the cuttlefish’s flesh which is poisonous. In other words, flashing bright colours warn predators to stay away from what would be a toxic meal.

The Ferraris report encountering many of these fascinating critters in both Kapalai and Lembeh.