Meet the Mantis Shrimp

Let me introduce you to one of our favorite marine creatures: the mantis shrimp. Why are they a favorite? They're cute (sort of), they're very smart (for a crustacean), and they're fun to watch. Unfortunately, they're also difficult to photograph -- more on this a little later!

The individual in the photos on this page is a Shortnose Mantis Shrimp (Odontodactylus brevirostris), from Hawaii. I know that the critter looks pretty big in these photos, but it's not. These are macro images. The mantis shrimp in these pictures was only about two inches (5 cm) long. You can click on any of the photos to see a larger view.

Despite the name, mantis shrimps are not true shrimps. I guess I don't need to explain that they are not mantises, either -- although they apparently acquired their name because they resemble praying mantises somewhat. Like crabs and lobsters and true shrimps, mantis shrimps are Crustaceans.

All mantis shrimps belong to the order Stomatopoda. Stomatopods have a number of features that set them apart from other crustaceans. Among the most notable -- and noticeable -- are their raptorial arms, and eyes that are highly evolved.

Mantis Shrimp Eyes

I've always wondered what the undersea world looks like through the mantis shrimp's eyes, because their eyes are like no other eyes. Take a look at the photos, and notice that the eyes are set at the end of stalks. Each eye is independently movable -- and they seem to move constantly, giving the critters a hyper-alert look. Each eye is trinocular, that is, each has three separate perceptual regions. This would be sort of like having built-in trifocal lenses, except that instead perceiving things at three different levels of magnification, each eye region is specialized to perceive a different kind of visual information -- but all at once.

Mantis shrimp eyes are capable of hyperspectral vision. In other words, not only can they see the visible light spectrum, like we can, but they also can see spectra of light that we cannot, including infrared and ultraviolet. Very recently it was discovered that mantis shrimps have the ability to perceive circular polarized light, too.

Raptorial Appendages

The mantis shrimp's raptorial appendages actually are legs that have evolved into claw-like arms, specialized for killing prey. There are two types: some species have thin, barbed raptorial arms that can spear prey; others have club-like raptorial appendages that smash their prey. (The mantis shrimp species in the photos is a 'smasher'.) When mantis shrimps are at rest or walking about, they keep those killer appendages folded up like closed jack-knives against their bodies, just as the creature in these photos is doing. When they go after prey, those appendages unfold at an incredible speed and they spear or whack the prey.

The spearers tend to choose soft-bodied prey like worms and little fish. The spearers are ambush predators. That is, they sit quietly and concealed until prey comes along and then they attack. In contrast, the smashers usually pursue their prey -- and that is one of the mantis shrimp behaviors we love to watch, when we get the chance.

The smashers use their raptorial arms not just to kill prey, but also to break it apart to eat. The species in the photo eats things like small crabs, and gastropod snails that live in shells. When the mantis shrimp sees one of those and goes after it, first he punches it silly, then he uses his raptorial arms to crack open the shell so that he can pick out the meat with his little forward legs, which are also specialized for that purpose.

The Star of the Puako 'Petting Zoo'

The mantis shrimp in the photos on this page lives off the coast of Puako, Hawaii in an area where we have made countless dives. When you dive in the same area again and again and again over a period of years, you become aware of things that a visiting diver probably never would notice in the course of just a few dives. One thing you learn is where all the different types of creatures live. Except for pelagics that roam the open sea, most marine creatures have a relatively small range. Once you spot where they live, you can usually count on seeing them in the same general area any time you go there. Once you know where to look, there they will be.

Puako has a wonderful fringing reef that parallels the shoreline for a couple of miles. The coral reef area is beautiful, and very accessible, but there are areas beyond the reef that are just as fascinating, if not quite so pretty. Where the seaward edge of the reef ends there is a steep slope. The top of the slope has many rocks and is still covered with quite a lot of coral, but deeper on the slope where less sunlight penetrates there is little live coral. There are more rocks, plus lots and lots of coral rubble -- lumps of dead coral washed down the slope from the reef over time. At the base of the rubble slope the terrain levels out into a sandy plain.

There is an area near the base of the rubble slope, at a depth of about 100 ft (30 meters), that we named the Petting Zoo. We called it that because it teems with small creatures. Sometimes we would go directly to the Petting Zoo, plop ourselves down in one spot, and spend the entire dive watching all the little creatures go about their business. You can learn a lot about marine creatures' behavior that way.

On one of our visits to the Petting Zoo, we noticed this particular mantis shrimp. Some mantis shrimp species are nocturnal, i.e. they only come out at night. This species works the day shift. We first saw him when he emerged from his burrow and began scurrying about. Mantis shrimps can swim a bit. If you look at the second photo above, you'll notice that this creature has a tail not unlike that of a lobster. They can use their tails to propel themselves through the water for short distances, but their more usual method of locomotion is to run about. Notice I said run. They move quickly -- usually too quickly to get a good macro shot.

Mantis shrimps live in burrows. This one had excavated a double-ended tunnel under the sand. I have no idea what it's like inside the burrow -- we used to joke that he probably had an overstuffed chair and a TV in there for all we knew. We did notice that outside the entrance to the burrow we would sometimes see pieces of broken shell in little piles. A few times we saw the critter in the process of housecleaning -- literally throwing bits of shell out the door.

On successive visits we saw this mantis shrimp stalk and kill prey -- usually a small crab. One time we saw him smack a crab that was bigger than he was, dismember it, and drag the body to the opening of his burrow. The mantis shrimp disappeared inside the burrow for a few minutes, then re-emerged and whacked the shell of the now legless crab a couple of times to crack it open and began to dig out the 'meat' for his feast. We watched him until it was time for us to begin our ascent. He was still working on the crab when we left. When we came back a day or two later we looked for the remains. Sure enough, there was a recognizable piece of the crab's empty shell not too far away from the entrance to the mantis shrimp's burrow.

I mentioned in the first paragraph of this article that mantis shrimps can be difficult to photograph. That's because they seem to be in motion constantly when they are outside their burrows. It's not too difficult to get a shot of one peeking out of its burrow, but capturing an image of the whole animal had eluded me for years.

Then one day at the Puako Petting Zoo, this little mantis shrimp came out of its burrow and just stood there looking at us. And -- Hallelujah! -- not only did I have my camera, it was set up for macro photography. Moving as slowly as I could, not to startle the critter, I lay down on my belly on the sand at the edge of the rubble slope, and sort of inched toward the mantis shrimp. He didn't run away.

I focused carefully on his wonderful eyes and pressed the shutter release, figuring this would probably be my one and only shot. So often in underwater nature photography, the flash of the strobe startles a photo subject and it quickly leaves, so one shot is all you get. But no, not this mantis shrimp. I expected him to high-tail it to his burrow, but instead he actually came toward me a bit, stopped and turned sideways, almost posing. Now practically touching him with the end of the lens port, I took another shot, and a third.

Then he turned the other way and positioned himself as if to say, "How's this? Can you see my tail a little better now?" I shot once more, and then he finally scampered over to his burrow and disappeared inside. I did press the shutter one more time while he was in retreat, but his movements had stirred up the sand by then.

I've often wondered what it was that made that mantis shrimp decide to be such a cooperative photo model that day. I've never again had an opportunity like that.

WW #31 - After While, Crocodile

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Do Not Disturb: Sleeping Fish

We all need our rest, and so do the fish in the sea. Fish don't sleep exactly like we do. For one thing, they don't have eyelids, so they can't close their eyes. Nevertheless, most fish we know about do take their rest for some part of the day or night, on a fairly regular schedule.

Some fish -- especially pelagics -- hunt at night, and rest during the day. Most reef fish are very busy during the day, so they rest at night. They stop moving about and enter a sleep-like state. While they are resting, they are generally sluggish and not very alert. We try our best not to startle them or disturb their rest during our night dives.

Some fish lie on the bottom to rest, while others hang motionless in the water column. Small fish, in particular, often hide while they are in their somnolent state so that their predators can't find them and eat them. Staying out in the open to rest definitely would give their predators an unfair advantage. In the first photo on this page, a tiny fish called a Pygmy Toby (Canthigaster pygmaea) has snuggled itself amongst corals and sponges to "sleep."

In the second photo, a small fish has chosen to settle into a stand of fire coral to takes its rest. We're not sure what species of fish this is, although the shape suggests that it is some kind of Damselfish.

In addition to hiding, another strategy that many fish use to discourage predation while they rest is to change color. Their color may darken or become mottled during periods of rest, helping them to blend in with their environmental background.

Some species of Parrotfish hide themselves by spinning a slimy cocoon around themselves. The mucous cocoon is secreted from an organ in the head of the Parrotfish. (Sorry, I don't have a photo handy.) It is thought that, in addition to hiding the fish, the cocoon also masks the animals' scent, making it harder for predators to locate them.

Both of the images on this page were captured during night dives in the Red Sea, along the coast of the Sinai Peninsula.

The Leaf Scorpionfish

Meet the Leaf Scorpionfish (Taenianotus triacanthus). This little fishie is one of the smallest members of the Scorpionfish family. This fish family, Scorpaenidae, gets its name from the venomous spines that most of the fishes in the family bear. (Regular readers of The Right Blue will recall our posts about the Turkeyfish/Lionfish -- another member of the same family.)

The Leaf Scorpionfish gets its name from its appearance. When you see one in its natural environment, it really does look like a leaf, rather than a fish -- until you spot its eye! Members of the Scorpaenidae family tend to be "lie-and-wait" predators. They tend to stay still in one spot until their prey happens past, and then they pounce very suddenly. They rely on camouflage so that they can blend into their surroundings, making it easier for them to surprise their prey.

The bodies of Leaf Scorpionfish are laterally very flat, which certainly contributes to their leaf-like appearance. This little fish not only looks very much like a leaf, it also behaves like a leaf! If you stay still and watch one for awhile, you'll see the little guy rock back and forth every once in awhile, just as a leaf or a stray piece of seaweed would do if it had settled on the reef. This, too, seems calculated to trick potential prey.

The Leaf Scorpionfish is a small species -- maximum length is about four inches (10 cm). They come in lots of colors -- yellow, reddish, purple, brown, pale pink, and off-white. They often have blotches, which enhance their camouflage, and they sport little fleshy appendages on their heads and chins that look like little weeds growing on them.

The photos on this page show examples of some of the color variations of the Leaf Scorpionfish. Despite the range of colors, they are all the same species. (Click on the photos to enlarge.)

The first photo on this page shows a purple Leaf Scorpionfish. You can see that this individual has a lot of blotches. If you see a scuzzy-looking Leaf Scorpionfish, he's probably getting ready to molt, which they do periodically. Soon after they molt they look much less blotchy. Sometimes the color looks a bit different after molting, too.

The second photo is a 1:1 macro shot of a Leaf Scorpionfish that we watched over a period of many months. In the second photo, you can see the little fleshy appendages on the fish's chin quite clearly. It's all part of the disguise.

We've noticed that when one of these fish finds a good spot on the reef, they tend to stay put in the same small patch of real estate for a long time. Once one is located, it's a safe bet that a diver will be able to return to the same spot again and again, day after day, month after month, and see the same little fish. Good dive guides know this, and that is why they can reliably lead divers and underwater photographers to a Leaf Fish almost at will.

The final photo on this page shows one more color variety. This yellow Leaf Scorpionfish is perched on a coral head. We have noticed that smaller Leaf Scorpionfish often tend to hide in the coral this way, while the larger ones seem to prefer a spot on a rocky bottom. We don't know why this is so, but we surmise that the little ones may feel safer in the coral, since it affords them some protection. They can hunker down if there's a lot of surge, for instance.

I took all of the photos on this page at Puako, Hawaii, at depths ranging from less than 20 feet (6 m) to about 125 ft (38 m).

Wordless Wednesday #16 - Red-spotted Sandperch

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A little fish with a big job

This is an enlarged photo of a little bitty fish --but he's a little fish with a big, important job. Meet the Hawaiian Cleaner Wrasse (Labroides phthirophagus).

These little fellows -- only two to four inches long as adults -- make their living by keeping other fish clean. They are an important part of the reef community.

The little cleaner wrasse stakes out a spot on the reef, usually near a prominent coral head. He hovers above the coral in a head-up posture and wiggles. That's the cleaner wrasse equivalent of turning on a neon sign that says "OPEN."

Other fish come as clients to the cleaning station to be rid of bits of old scales, dead skin, and small parasites that they may have acquired. The client fish swims up to the cleaner wrasse and stops. The cleaner wrasse approaches and gives his client a once over, looking all for extraneous bits, which he then pecks off. This service can take anywhere from a moment, to several minutes, depending on how big the client is -- and how scruffy!

Here's a photo of a Hawaiian Cleaner Wrasse servicing a Spotted Puffer (Arothron meleagris) at Puako. [And yes -- in case you were wondering -- the Spotted Puffer is a first cousin to the Stripebelly Puffer that we showed you a number of weeks ago. They belong to the same genus.]

These cleaning stations serve pelagic (open ocean) fish as well as reef fish. It's not unusual to see animals like sharks, manta rays, and large jacks waiting their turn at busy cleaning stations.

Once a cleaning station is established, it will exist for a long time -- even for years -- in the same spot. Client fish learn where it is, and return to it again and again. The busier cleaning stations may have several cleaners at work -- much like a barber shop with multiple chairs.

Some fish that don't clean other fish full time, do become cleaners from time to time. An example that comes quickly to mind are the several species of fish that clean turtles here in Hawaii. It happens that turtles' carapaces sometimes get covered with a film of algae. Certain fish that are primarily algae-eaters will clean the turtles' shells -- not because they are trying to clean them but because they like to eat the algae, regardless of whether it's growing on a rock, on a coral head, or on the back of a turtle.

Several species of shrimp also make their living cleaning other animals on the reef, and they act as dental hygienists as well. It's not at all uncommon to see a toothsome moray eel -- jaws agape -- with a little cleaner shrimp busily pecking about inside the eel's mouth. (Moray eels don't floss!)

We've played with both the cleaner wrasse and the shrimp to see if we could get them to work on us. The wrasses rarely seemed very interested in us, save for occasionally snipping at Jerry's whiskers. The cleaner shrimp are another story entirely. They'll readily crawl around on our hands, pecking at our cuticles, for example. And by the way, that REALLY tickles!

The cleaner wrasse in the photos on this page is endemic to the Hawaiian Islands. That is, it is native to our waters and exists naturally only here. But, it has close relatives in other parts of the world that look very similar, and which serve the same function in their own locales.

Wordless Wednesday #15 - Home again in Hawaii

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Male fur seals at Taiaroa Head

We spent two days exploring the Otago Peninsula, outside the city of Dunedin on New Zealand's South Island. On the second day there we visited a small cove called Pilot's Beach, a small crescent of sand bordered by a jumble of rocks on each side. The cove is situated on the sheltered side of Taiaroa Head, the wildlife reserve at the tip of the peninsula.

We saw Blue Penguin burrows near the beach, but not the penguins themselves since we were there during the bright midday hours. The penguins only come ashore at dusk to spend the night in their nests, returning to the sea again at first light.

We did get to see several good-sized male New Zealand Fur Seals (Arctocephalus forsteri). While we had seen some female fur seals sunning themselves at Kaikoura the week before, this was the first time we had seen the larger males of the species.

Several of these guys were swimming rather close to shore. We sat on the rocks beside the beach for quite awhile so we could watch them. We were surprised to see them lazily swimming on their backs at times, sort of lolling about, paddling just a bit with their front flippers, while their back flippers poked up above the water's surface. Unfortunately they did this too far offshore to photograph clearly, since I didn't have a telephoto lens.

Then one seal seemed to notice us, and swam toward the rocks where we sat, as if he had decided to have a look at us.


He made one pass, and then swam seaward for a bit before circling back to inspect us again. We didn't move (except to raise the camera). This time the seal came even closer, paused right in front of us, and raised his head out of the water for a better look at the strange jeans-clad mammals sitting on the rocks.


He stayed there for a few minutes, just staring at us. We stared back! He came in just a bit closer, and we began to wonder if he was going to haul out right onto the rocks where we were sitting.

But no -- in the end, he just rolled over onto his back and swam away from shore. We were sorry to see him go back out to sea, but we were grateful to have had such a great close encounter with this very photogenic marine mammal.

Not too far away, there is a fur seal breeding colony populated by females and a few dominant males. Those older males are very territorial and do not appreciate interlopers. They will challenge and fight younger males who intrude at the colony.

We were told that the fur seals we saw in the Pilot's Beach area are mostly younger males who come to the area to rest in the sheltered cove, away from the threat of the older males.

Wordless Wednesday #9 - November 28, 2007

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Turkeyfish or lionfish? Different name, same critter

Several days ago I put up a couple of photos of a Hawaiian Turkeyfish -- as a sort of tongue-in-cheek reference to American Thanksgiving. 'Turkeyfish' is a common name for this fish -- but it is not the common name. In some circles, the same creature is called a 'Lionfish.'

Some of the readers who commented on the previous post seemed to know this, and found my Turkeyfish label to be a bit confusing. Unfortunately that is one of the problems with identifying things in nature by their common names: the names are not standardized. That is why I always include the scientific name (when I know it!) as well as the common name for the marine life in the photos I post on The Right Blue. Scientific names do not vary.

The angle of the photo on this page might give a little better clue as to why this fish might have earned either of its common names. It has this habit of spreading its spiny fins when it is disturbed, a display that must have reminded someone either of a turkey's tail, or a lion's mane. That seems to be the origin of both common names for this fish and its kin.

The scientific name for this fish is Pterois sphex. It belongs to the Scorpionfish family (Scorpaenidae). A characteristic shared by the fish in this family is that they possess venomous spines. This is their defense against being gobbled up by larger predators.

This particular species is endemic to the Hawaiian Islands. In other words, it is native to Hawaii, and it is not found elsewhere naturally. There are other fish of the genus Pterois elsewhere in the world. They all look quite similar, but close examination will reveal some clear distinctions among the species.

These other fish in the genus Pterois also are referred to as Turkeyfish or Lionfish, depending on geographical location and who's doing the talking or writing. At least one leading ichthyologist (fish biologist) prefers to apply the name Turkeyfish to the genus Pterois, and the name Lionfish to a different Scorpionfish genus, but most people seem to use the two common names almost interchangeably.

Some people who commented on the previous post mentioned that they thought they had seen this fish in a saltwater aquarium, presumably away from Hawaii. They may indeed have seen this species, or they may have seen one of its similar-looking cousins -- one of the other fish of the same genus that I mentioned above.

I don't know a whole lot about the fine points of the aquarium trade, but I do know that Turkeyfish/Lionfish are valued as "ornamental fish" and are collected for sale to aquarists. In fact, the population of these fish on our coasts has been depleted noticeably over the years as commercial fish collectors scooped them up in large numbers to sell.

The individual fish in the photo on this page (and in the previous post) has lived in the same small patch for years, along with a handful more of the same species. These fish do not have a very wide range, so once a diver discovers where they live, they can reliably be found in more or less the same spot day after day, and -- with luck -- year after year.

We know this to be true in more than a theoretical sense. Along with our friend Dan, we dived the same stretch of coastline at Puako, Hawaii several days a week for years, and we came to know where all of the permanent residents lived. We know precisely where these Turkeyfish/Lionfish live -- but we're not telling.

Why I love macro photography: Surprises

About a month ago I said I love macro photography (ultra close-ups) for the fine details that are revealed. The example I gave then was a photo of a tiny hermit crab with hairy legs and turquoise eyes. Neither of those features could be seen with the naked eye -- much less by a pair of eyes behind the faceplate of a dive mask! Those details only became visible when the photo was enlarged.

The photo at right is another example of the kinds of surprises that sometimes appear when macro photos are enlarged. I shot this image of a mushroom-shaped leather coral (Sarcophyton sp.) -- a type of soft coral with a sort of rubbery skin -- because it caught my eye as a perfect specimen, in miniature. Only when the photo was enlarged did we notice the face of the tiny little fish that was hiding under the edge of the leather coral. Click on the photo to enlarge it even more.

This coral specimen was maybe two inches (5 cm) high, so the little fish was too tiny to see clearly. (For the photographers out there, this is a 1:2 image.) We have no idea what species the little fish with the great big eye is, but we surmise it's a juvenile of a reef species. We love the way he's hiding, but peeking out curiously, too. The image was shot during a night dive in the Celebes Sea.

Wordless Wednesday - October 10, 2007

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Meet Myrtle the turtle

As I explained earlier, many green sea turtles live along the shoreline at Puako, Hawaii. They cruise around the reef, graze on algae and seaweed in the shallows, and sunbathe on the rocks and beaches there. We'd like to introduce you to one of those turtles.

This is Myrtle, a Hawaiian green sea turtle (Chelonia mydas). Over a period of several years, we got to know Myrtle quite well. Because we got to know Myrtle, we learned a lot about green sea turtles and how they live.

Myrtle's base of operations in Puako happened to be the particular little cove where we most often enter the water to begin our shore dives. While quite a few turtles hang out in that area, we noticed that one particular turtle had a small 'ding' right in the center of her carapace. That little blemish in her shell set her apart from the others and made her easy to identify. We named her Myrtle -- not the most original name for a turtle, I know, but it suited her. (Take a look at that face in the photo and tell me she doesn't look like a Myrtle!)

At the time we first encountered Myrtle, Jerry and I were living in Puako, right across the street from the little cove where this turtle lived. Our good friend Dan lived just up the road. During the time that we all lived there, Dan and Jerry and I visited the cove on a daily basis, whether we were diving or not. It was during this period that this spot became our favorite, and that we got to know Myrtle.

Once we learned to recognize Myrtle, we noticed that she was there almost all the time. So, one of the first things we learned from Myrtle is that green sea turtles are creatures of habit.

Sometimes we'd see her basking on the beach, 'working on her tan.' Most often we'd see Myrtle in the water close to shore, munching away on the limu (seaweed) that covers the rocks there in the shallows, just as she's doing in the photo at right. Occasionally we'd cross paths with her while diving out on the reef beyond the dropoff. More on that later...

Most of the sea turtles around Puako are quite laid back, especially when they're basking on the rocks or the beach. By this I mean that they are not very skittish in the presence of people -- almost as if they know they are protected by law, and that no human will harm them. (Either that, or the warm sun just makes them drowsy!)

The sea turtles in Puako can be a little touchy about having their space invaded when they are feeding, however. If waders approach them, they'll often pointedly shove off from the bottom and swim at least a few meters away. We'd see Myrtle do that, too, but then we noticed something interesting.

As I mentioned, we had almost daily encounters with Myrtle for years. We began to notice that if we waded past Myrtle while wearing our wetsuits and dive boots, she never spooked. Perhaps she grew accustomed to seeing us -- or rather our neoprene-clad legs and feet! -- and understood that the humans attached to those legs and feet were not going to harass her. That thought was reinforced by the fact that if we waded into the water bare-legged, bam! Myrtle would take off.

There is a sound reason why sea turtles tend to stay clear of anything unfamiliar, including people, while they are underwater. Sea turtles can stay underwater for a considerable length of time, but they are air breathers. They need to surface from time to time for a breath, so they have an innate fear of being cornered or restrained underwater.

Nevertheless, Myrtle often would pop her head above the surface and look right at us as we waded past her -- as long as we were decked out in our dive gear. We used to ask one another if we were imagining that she recognized us (or our neoprene), and of course we can't say for sure, but it did seem more than a coincidence that just as we'd pass by her, she'd interrupt her grazing and pop up as if to say hello.

As if! What she really did was exhale her turtle breath in our direction, and then she'd duck her head back under the water to take another pass at the limu buffet below. We'd do our dive, and an hour or so later when we waded back to shore, Myrtle would still be there. Once more she'd surface as we waded past, and give us another big whiff of limu breath.

We have lots of Myrtle stories. Next time, I'll tell you a bit more about this special turtle and what we learned from her.

Wordless Wednesday - October 3, 2007

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The 'eyes' have it

Awhile back I mentioned that I have a 'thing' for photographing the faces and eyes of creatures in the sea. If you've been following along, you've already seen the conch shell's eyes, and the cross-eyed cone shell. Here are a couple more portraits of critters' eyes.

The creature in the first photo, at right, is a Caribbean Reef Octopus (Octopus briareus). You can click on the photos for a larger view.

In addition to his eyes, take note of his amazing skin. That skin can change from a dark reddish color to the almost iridescent green of the specimen in this photo -- and almost every shade in between. This octopus (like many others) also can change the texture of its skin from smooth to rough in order to blend in with its surroundings.

Finding that octopus was a stroke of luck. The Caribbean Reef Octopus almost always hides in its lair during the day, so the only time a diver is likely to come across one is at night. Indeed, the individual in the photo above was encountered during a night dive at a place called Radar Reef on the north shore of Cayman Brac.

This next eyeball, on the left, belongs to a Blue-spotted Stingray (Taeniura lymma), one of the most easily recognizable of stingray species for obvious reasons. The first time you see one at close range, you can hardly believe your eyes. Those blue spots are quite dazzling.

Blue-spotted Stingrays are quite abundant in the Red Sea. That's where this one was photographed. It was resting on the sand at Ras Mohammed, near the southern tip of the Sinai peninsula. I approached it inch by inch, trying my best not to startle it so that I could get this macro shot of its eye.

This second photo of a Blue-spotted Stingray also was taken in the Red Sea. I'm including it here so that you can have a better idea of what the whole animal looks like.

What's missing from this photo, of course, is the stingray's tail. By the way, yes these animals do have a venomous stinger, but contrary to popular belief, it's not in the end of the tail, and they don't slash their tails around to try to sting prey -- or divers. The stinger -- actually a spine with a barb on the end -- is at the base of the tail.

They're quite shy and often swim away when a diver approaches. They look very pretty when they swim, because they propel themselves through the water by fluttering the edges of their body.

Blue-spotted Stingrays are one of the smaller species of stingray. To give you an idea of their size, the ones in the photos on this page were about one foot (30cm) in diameter.

Faces on the reef -- The buck-toothed wrasse

One thing that happens when you begin to take photos is that you start to pay attention to details you might not have noticed otherwise. For me, this noticing of details about my underwater photo subjects progressed in a systematic way.

When I first began to dive, I just saw "fish" and "crabs" and "starfish," but couldn't distinguish among the species of each. Over time I learned to recognize features common to different families of creatures. I could distinguish butterflyfish from angelfish, for example.

Next I learned to identify distinct species within families, and in some cases, whether individuals were male or female. My photos began to reflect that knowledge: I began to 'collect' species -- trying everywhere we went to photograph examples of as many different species as I could find.

Eventually I focused on details that reflected the creatures' individuality. In particular, I began to pay close attention to their faces or -- for creatures that didn't have faces in the usual sense -- their eyes. (This photo of a conch shell's eyes, and this one of a cross-eyed cone shell, are examples.)

Faces, more than any other visible feature, are emblematic of individuality. Our own faces are what instantly set us apart from one another visually. Sometimes we humans tend to overlook the fact that creatures in the wild also have faces -- and individuality.

We have accumulated a collection of photos that we call Faces on the Reef. We think that they illustrate the point that marine creatures, too, have individuality.

The little guy in the photo on this page is a Saddle Wrasse (Thalassoma duperrey). We just love the goofy look on his face, and those wonderful protruding front teeth. The one pictured here is a male, roughly 8 inches (21 cm) long. He was photographed at Honaunau Bay, Hawaii.

This species is very common on reefs in Hawaiian waters, and individuals can be quite friendly toward divers. They'll sometimes swim up and peer right into a diver's mask -- maybe they're looking at our eyes! -- and they'll often follow divers around the reef. If a diver should stop to turn over a rock to see what's under it, the Saddle Wrasse will be right there to look, too. If the wrasse sees something good to eat, he'll grab it and then move along to the next rock and wait, looking back at the diver as if to say, "Well come on, turn this one over next."

The Hawaiian name for the Saddle Wrasse is hinalea lauwili.

Muck diving - The tale of the cross-eyed cone shell

Okay, one more critter post, and then we'll move along to an entirely different kind of undersea adventure.

As I explained in my previous post, I was oblivious to the fact that snails (of all things!) had eyes until I began to photograph these creatures. Once I made the discovery, though, I always looked for eyes. In fact, eyes and faces became a recurrent theme in my underwater photos of marine animals.

Of all the critters I have photographed, the little creature on this page is the only cross-eyed one I've ever recorded. It's a Mediterranean Cone Shell (Conus mediterraneus), and the photo demonstrates the fact that the eyes, which are on flexible stalks, can move independently. I managed to shoot six frames of this very cooperative individual before it retracted completely into its shell. The eyes are 'crossed' in each of the six photos.

While the photo has a certain giggle factor, to me it also says something else: you never know what you're going to find or where you're going to find it. I photographed the cross-eyed cone shell in a shallow area near Cape Greco, on the eastern end of Cyprus. The area is known to divers for its rather interesting rocky terrain and some small caves -- but not for marine life.

I almost didn't take the camera with me on this particular dive, in part because a friend who had been there before us had mentioned that "there was nothing there worth photographing." At the last moment, I decided to set up the camera for macro photography, just in case. As it turned out, that was the right thing to do.

We spent most of the dive in the shallows, on our bellies, rummaging around in the the sand and pebbles looking for little critters. This is called 'muck diving' -- a genre of underwater exploration pursued by photographers and nature lovers who have learned that while lush coral reefs may be the most obvious place to find photogenic marine life, there are many small and interesting creatures living in less glamorous habitats, too. Muck divers look for and find great photo subjects -- like our cross-eyed cone shell -- on sandy bottoms and mud flats, in sea grass beds and mangrove swamps.

The lesson here is that there is always something to see, and something to photograph in just about any marine environment. You just have to know what to look for and how to find it.

Meeting critters, eyeball to eyeball

You've heard of 'snake eyes' -- but have you ever seen snail eyes? I mean, who knew?! I certainly didn't realize that snails had eyes -- nor had I even thought about it -- until I got serious about underwater photography.

I made the discovery one day when we found a large conch shell on a sandy patch and I decided to photograph it. As we approached the shell, it was clear that it had a living animal inside, because it had left a slightly indented trail in the sand as it had moved along.

First I took some shots of the shell where it lay on the sand, without disturbing it. Then I decided to turn it over to photograph 'the shiny side' -- the part kept smooth and pearly by the animal's secretions.

Conch shells, like other spirally constructed sea shells, are inhabited by gastropod marine snails. In fact, the shell itself is secreted by the snail over its lifetime. In the case of this particular species of conch, the snail inside often is quite large, and the shell can be up to about 6 inches in length.

When I turned over the one I was going to photograph, the snail retracted to hide itself in the depths of its shell. I set the shell back down on the sand, shiny side up, and only the tiniest bit of its mantle was visible in the aperture of the shell as I proceeded to photograph it.

I paused for a moment, kneeling on the sand while I twiddled with a few camera settings. When I turned back toward the shell to shoot again, I was amazed to see that the snail was peeking out of its shell at me. I managed to get this one shot of those wonderful eyes on their flexible stalks before the critter, reacting to the flash, disappeared into its shell once more.

I turned the shell over again, placing it back on the sand the way we had found it, and we continued the dive. I wondered anxiously if I actually had managed to capture those eyes on film, and could hardly wait to see the slides. As you can see, the shot was successful.

For the record, the species in the image on this page is a 'Milk Conch' (Strombus costatus). It was photographed in the Caribbean Sea on a sand flat just west of Jackson Bay, Little Cayman island.