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By Hergen Spalink

The mimic octopus (Thaumoctopus mimicus) was first discovered in 1998, here in Sulawesi.  The mimic is a bottom dwelling octopus that is found on sandy slopes between 2 and 12 meters and has an arm span of about 60cm.  T. mimicus  stands out from its fellow benthic octopuses in that is seems to "mimic" the appearance and behavior of poisonous or noxious animals that share its habitat, hence its name.  Varying its color pattern, body posture, and movements, this bottom dwelling octopus tends to impersonate a variety of flat fish, lion fish, anemones, mantis shrimp, and even sea snakes.  Observations of several individuals over several weeks have even led researchers to believe that the mimic is capable of deciding which type of animal to mimic based on their particular surroundings at that moment.

Impersonation of these distasteful or harmful animals allows the mimic to forage the sandy slopes of its habitat during the daytime, in full view of predators, looking for crabs or shrimp burrowed in the sand.  Other cephalopods use their coloring to camouflage themselves until  predator has passed, blending into their background by assuming the same color and texture of coral, rocks, or rubble.  The mimic moves along the sandy slopes, using one of its tentacles to probe holes and tunnels for potential prey.  As a last resort, the mimic may also completely enter a burrow to escape a predator (or an overzealous photographer), tunneling through the sand and emerging away from the point of entry.  At night the mimic seems to stay hidden in the sand, often occupying the same spot for a few days in a row.  The mimic octopus is definitely high up on every visitor to Lembeh's critter wish list.  One of the many interesting things about mimics, is their dynamic presence, you never know what they are going to do next.  Capturing a good mimic image can be challenging for the same reasons that make animal so sought-after.

Mimic Octopus Underwater Photography Equipment Tips

DSLR:
Having shot mimics with both macro and wide angle equipment, it comes down to preference.  With an arm span of up to 60cm, the subject is definitely big enough to be shot with a wide angle zoom lens, or even a close focus wide angle setup like a tele-converted fisheye.  The main consideration when choosing the lens should be the type of shot you would like to have.  If you are focusing on behavior or environment, perhaps a wider angle lens is desirable, whereas close-ups of their patterns and features may warrant a macro lens.  It is possible to shoot their behavior with a macro lens, but stronger strobes and clearer water conditions may be necessary to get good results.  A 60mm or 50mm lens seems the most versatile at getting both close-up and behavioral shots, yet does require getting closer to the octopus, increasing the chance that it may spook and hide.

Compact:
Compact cameras often capture some exceptional mimic images, as they have the ability to go wide or macro as the behavior of the mimic changes.  The macro mode should definitely be used to capture close-up images of the octopus, yet may not be necessary for some of the mimicry behavioral shots such as impersonating stingrays or lionfish. 

Ligthing:
A strobe is a must for shooting mimics, as their skin tone is similar to that of the surroundings.  In addition, the use of shadow is essential in many situations to bring the animal out from it's background in the image. Snoots or other creative lighting techniques may also help separate the animal from it's bland surroundings. 

Mimics Octopus Underwater Photography Techniques

Hide and Seek:
The most essential piece of equipment when setting out to shoot mimics is an excellent spotter.  The spotter's task is not as simple as finding the octopus.  The hunt for the mimic begins by carefully swimming over big empty sandy slopes (exciting!).  Once the guide spots a mimic he will stop the group before they get within a few meters of the animal (hopefully!).  Here in Lembeh, our guides carry a modified "muck stick" that is about one meter long that they use specifically for "enticing" octopus. 

Most mimics are found in or near a hole in the sand.  Having spotted a mimic, the guide will extend the long muck stick, keeping it very close to the ground, towards the octopus, stopping just short of their hole.  They then stir up the sand, just as a burrowing crab would do.  This disturbance is like catnip to a mimic, they can't resist.  The mimic will usually exit the hole and inspect the disturbance.  At this point, the guides will begin to move the guests towards the mimic (slowly!). 

Manic Mimics:
Mimics (like most octopus) seesaw between bursts of speed and sitting for minutes at a time without moving.  As a shooter you must have patience.  Use those moments of rest to examine your previous shots and adjust your exposure.  The mimic has a strong color contrast with alternating brown and white bands that they can vary in intensity, making the choosing of settings a crapshoot.  I choose to base my exposure upon their most brilliant display (full white stripes), as this seems to also make for the most striking images.  As with other cephalopods, it is important for the eye of the animal to be in focus to make a coherent image.

Shadows and Angles:
The octopus can also turn itself a light-brown when it performs some of its mimicry, making it appear similar to other benthic octopus species such as the long-arm or veined.  Although their behavior is interesting in these "states of mimicry", often times their color scheme is less than exciting which can pose a lighting challenge.  By increasing the power differential between your strobes, or simply using one strobe to create strong shadows, it is easier to make the mimic stand out from its background.  Getting as low as possible to the sand will also improve your chances of creating an image that "pops".

Avalanche Divers:
As mentioned above, the mimic may decide to take off, speeding across the sandy flats.  Being able to follow the animal without causing an avalanche of sand is critical, since the avalanche might not stop when you do. This will cause a cloud of sound to surround you and cloud of sand.  Proper muck-stick use and frog-kicking are all ways that can help you maintain a sand-free shooting environment.

Give 'em Room:
As with any animal, if they feel threatened, they will flee or fight.  Since the mimic is not known for its lethality towards photographers, it flees.  This usually means finding the nearest hole and disappearing.  By giving the mimic a sufficiently wide berth, you can help insure they won't disappear completely.  If you're lucky, they will instead use that hole as a "base of mimicry" pretending to be either a mantis shrimp, anemone, or snake eel.   As with any octopus, swimming directly over the top of them may cause them to retreat completely into their hole.  Instead, stay off to the side and try to remain as motionless as possible.  Octopus are smart animals (anyone remember the 2010 World Cup?) and if they realize you are not a threat or a hindrance to their feeding, they may choose to ignore you and go about their business with you around.  By giving them sufficient room to feel comfortable, you may be able to put the octopus at ease to your presence, allowing you to stay longer with your subject and get better results.

Threesomes are OK:
More than one shooter can photograph the same mimic at the same time.  The variety of interesting angles and perspectives that can be done with mimics means that there is no one "right way" to shoot them (as opposed to say Pygmy Seahorses, which would be challenging have multiple people shoot at the same time and achieve acceptable results).  In general, you are further away from the subject and it is constantly in motion.  As always, be aware of you're subjects state - if it seems overwhelmed or trapped, back off, let it recover before shooting it further, if at all. 

Resources:

 Mark D. Norman, Julian Finn, and Tom Tregenza "Dynamic mimicry in an Indo–Malayan octopus" Proc. R. Soc. Lond. B September 7, 2001 268:1755-1758; doi:10.1098/rspb.2001.1708

Norman, M.D. 2000 Cephalopods: A World Guide.  Hackenheim, Germany: Conchbooks.

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