Another Side of The Right Blue

This will be quick: I just have to share something.

As I do most days, this morning I opened my Google Reader and began to browse the feeds of some blogs I follow. When the feed for Go Visit Hawaii loaded, I was taken aback by what I saw. It was a photo of the view from my window!

Sheila, has been running an interesting series on Go Visit Hawaii called "The Colors of Hawaii." She asked readers to submit photos of Hawaii that highlight a particular color. Unbeknownst to me, Jerry submitted one in the blue category (of course!), and Sheila published it today.

Click on over and have a look at Colors of Hawaii: Big Island Blues on the Go Visit Hawaii blog. And while you're there, you might enjoy looking at some of the other Colors of Hawaii, too.

P.S. I hear that Sheila is still accepting photos for The Colors of Hawaii, so if you have one you'd like to share, send it to her. The details are here.

UPDATE Aug. 6, 2008: Sheila has put a new post on her Go Visit Hawaii blog that lists all the Colors of Hawaii posts so far. She's still accepting more photos.

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.

On a collision course with critters in the sea

This post was inspired by a comment on our Rush Hour On the Reef photo in which Chris asked, "It's probably a fairly silly question, but do you ever get run into by fish?" The short answer is, "No, not really." But we have had some very close calls.

Little fish, like the fast-swimming Fuslier Fish we showed you recently, often approach in a large school, and at a high rate of speed, but they manage to steer en masse around obstacles -- including divers -- by making high-speed turns in unison, or simply by splitting the school for a moment, with half the fish passing on each side of the diver. Once past the obstacle, the fish reunite into one school again and continue on their way.

Other kinds of small fish that form dense schools do more hovering than swimming around. Sometimes a diver will encounter a dense school of Sweepers or Glassfish hovering in an underwater canyon, or even inside a shipwreck or a cavelet. As the diver (or a large fish) swims toward the apparent wall of little silvery fish, they may scatter. More often, though, the school simply parts like two halves of a stage curtain to allow the bigger swimmer to pass through, then closes again afterward. It can be an amazing sight, and an almost dream-like experience.

In sum, smaller fish usually get out of the way of larger fish and divers, one way or another. Now let's talk about larger fish -- much larger fish.

Over the years, we have noted that the larger the animal, the more likely it will notice divers and even come close to have a look. On occasion they come very, very close.

Consider the photo at right: that's a Whitetip Reef Shark (Triaenodon obesus). I first saw this particular shark while it was about 75 feet (23 meters) in front of me. It was coming toward me at a leisurely pace, so I settled into position and aimed my camera, hoping it would come close enough for a good photo.

Through the viewfinder I watched it come closer and closer, heading straight at me now. It had spotted me, for sure.

About two seconds before I snapped the shutter for this shot I thought I might have to duck out of the way, because the shark had now picked up speed a bit and I feared it might bump into me, head on. I knew it had seen me, so it was starting to feel like a game of chicken! Then at the last moment, the shark made a sharp right turn directly in front of me and swam off (as if that had always been what it had intended to do!), avoiding a collision.

This was neither the first nor the last time that one of the larger species on the reef had intentionally come right up to one or both of us to look us over, and made a very close pass. In fact, sharks and barracudas often do this. So do large groupers, wrasses, jacks, and every kind of marine mammal we've ever been with in the water, including dolphins and whales. (Long-time readers of The Right Blue will recall our tale of close encounters with humpback whales.) But none of these cases ended in a collision, either.

On the other hand, we've had, or witnessed, quite a number of very close calls -- near-collisions with big critters in the sea. Usually this happens when two critters, or rather a critter and a diver, round a corner or swim over a rise at the same time from opposite directions, unaware that the other is approaching until they nearly collide.

Another scenario for close scrapes occurs when a diver inadvertently startles an animal, and the animal reflexively attempts to escape the scene. Once, while diving with a good friend and a visiting diver, we took the visitor to a place where we knew Whitetip Reef Sharks went to rest. The spot was a sheltered cavelet in the face of an underwater cliff. We approached carefully from below the cavelet and quietly positioned ourselves so that we could peek inside. My friend shined his light onto the ceiling of the cavelet, so that the light reflected down just enough for us to see two sharks 'sleeping' inside. The visitor, wanting to get a better look, shined his light straight into the cave, right into the face of one of the sharks. The shark startled and shot out of the cavelet like a missile, grazing my friend's head on the way, and knocking off his dive mask in the process.

On another occasion, Jerry and I passed below a ledge where drowsy sharks sometimes lolled. I was in the lead, with Jerry following just a meter or two behind me. As best as we can reconstruct what happened, we think my exhaled air bubbles must have passed by a shark on that ledge and disturbed it. It was another 'missile launch' situation, but this time the shark swam between Jerry and me, and as it did, it passed right in front of Jerry's face. Reflexively, Jerry's arms shot forward and he shoved the shark. This shocked the poor shark even more, and it sort of jack-knifed sideways. By this time I had turned around, and now the shark went berserk, probably thinking we were trying to corral it. It swam around frantically in a very tight circle for two or three revolutions (like a puppy chasing its tail) before it saw its opening and catapulted itself from between us and went careening down the reef. We stared after it until we could no longer see it, our hearts pounding from the unexpected excitement on an otherwise tranquil and leisurely dive.

Here's one more photo from a near-collision we had with a large stingray. From a technical point of view, it's a lousy shot, but I'm posting it anyway because it has such an interesting story.

We were on a deep sandslope, where I was shooting macro photos of small creatures that inhabited the nooks and crannies of a large, irregular rock. We were both crouched over the rock, engrossed in the task. Jerry looked up briefly, just in time to see an Amberjack swimming up the slope, heading right toward us. Jerry nudged me and pointed toward the Amberjack. I turned my head to look, and noticed that there was another, darker creature moving along the sand, beneath the Amberjack. In one of those 'lightbulb' moments of comprehension, we instantly recognized that we were witnessing a rare sight: a large deep-dwelling stingray species hardly ever seen by divers. Even though my camera was set up for macro, I whirled around and snapped this one shot, just as the Amberjack veered away, and the stingray sort of skidded to a stop, touching me, but just barely.

What looks like snow in the photo is light from my camera's strobe, reflected on sand particles that the stingray and I had stirred up at that moment. An instant later the big stingray did an urgent about face, stirring up a huge cloud of sand particles as it quickly retreated back to the depths.

In case you are wondering about the stingray, it looked to be about 1 to 1.5 meters across. It is either a Hawaiian Stingray (Dasyatis brevis) or a Brown Stingray (Dasyatis latus), but the photo is not clear enough to determine which it is with certainty. Both are known to inhabit deep sandy areas in Hawaii. They are uncommon around reefs, so they are rarely seen by divers. This was one of only three or four encounters we have had with one of these stingrays in all our years of diving in Hawaii, and this was the only time I got to photograph one.

Remembering Brutus, the Great Barracuda

You would think that after doing thousands of dives at hundreds of dive sites around the world, we would not remember encounters with individual fish. Who knows how many different fish we have seen in our long years of diving? Yet there are a few individuals among the masses that do stand out in our memory. One of those was a big silvery fish that hung out near our home reef at Puako, Hawaii for the better part of a year.

That big silvery fish was a Great Barracuda (Sphyraena barracuda), just like the one in the photo at right. I photographed that one in the Caribbean, but we have seen this species all over the world, and have had many close encounters with them. Most of our encounters with barracuda were unremarkable, until we crossed paths with the one we came to call Brutus.

Brutus the Great Barracuda was 'great' in more ways than one. He was great in size: we figured he was about five feet long and probably weighed around 70 pounds. He also was a great companion: if he spotted us from a distance he'd hurry to us, and then follow us around for most of our dive.

Seeing a big barracuda like Brutus underwater can make the hair on the back of a diver's neck stand up and prickle, but Brutus never harmed us, nor did he ever give any sign that he wanted to do anything more than watch what we were doing. In fact, he could be downright nosy.

Usually Brutus followed us at a respectful distance of, say, 20 to 30 feet. But there were times when we'd stop to look closely at some tiny little creature, and that distance would close until we'd have Brutus looking right over our shoulders. I don't know why he did that. Maybe he thought we might have found something good to eat, and he didn't want to miss it. What I do know is that sometimes we'd turn our heads, and there would be this big barracuda face with the gnarly-toothed grin right there!

When Brutus first started to follow us around, we thought maybe we were imagining it. We thought maybe the big fish just happened to be going where we were going, and was not really following us at all. So, along with our friend Dan, we cooked up an experiment: We agreed ahead of time that if we saw Brutus and he started to follow us, we would reverse direction, swim past him, and see if he then turned around and stayed behind us. He did. After a few more rounds of this we concluded that he really was following us intentionally, and not by chance.

Then we noticed that Brutus seemed to prefer Jerry to Dan and me. When the three of us were diving together, it was our habit to swim more or less parallel to one another, but about 15 or 20 feet apart. We noticed that when we fanned out like that, Brutus would watch all of us, but seemed to follow Jerry more closely. So, we planned another experiment. On one dive, Jerry would be positioned in the middle, with Dan and me at either side. On another dive Jerry would take an end position, and either Dan or I would take the middle spot. Sure enough, regardless of which position in the line-up Jerry took, Brutus would be right behind him.

What was it about Jerry that attracted this big barracuda? The probable answer came one day when I stopped to look at something, while Jerry and Dan swam ahead. When I looked up to see where they were, I spotted Jerry right away. He was wearing a wetsuit that had bright yellow sleeves, and had on yellow fins, too. The yellow was very visible, even from a distance. I couldn't see Dan until I got closer. Dan's suit was all black, just like mine. It was one of those 'lightbulb' moments. "Aha!" I thought. "That's it!" It probably was the yellow in Jerry's dive attire that attracted Brutus.

Barracuda are believed to be attracted to shiny things, probably because much of their diet consists of little silvery fishies. It occurred to me that, while Jerry's fins and wetsuit were not shiny, the yellow color definitely stood out in contrast to the background. You know what's coming, I'll bet. One more experiment.

The next time we went diving, Jerry and Dan swapped suits. Jerry wore all black, and Dan now wore the suit with the bright yellow sleeves. Along came Brutus. We fanned out across the reef, with Dan in the middle, dressed in Jerry's suit. Just as we had hypothesized, Brutus now followed behind Dan. When they switched positions, Brutus still followed Dan. We concluded that it was indeed the yellow in the suit that had attracted the barracuda. After that, we referred to that suit as Barracuda Bait!

So, if you're diving in waters where there are Great Barracuda about, and you don't want to attract their attention, do not wear a high-contrast outfit underwater. Wear a suit that blends, not one that stands out. Don't be barracuda bait.

Two Brief Announcements

We have decided to make one short post with two brief announcements, sharing some Hawaii-grown news before we return to our series about diving in the early days.

Our first announcement is that The Right Blue has been rated E, for Excellent, thanks to a fellow blogger from Hawaii. "Mahalo nui loa" to Evelyn, of Homespun Honolulu, for nominating The Right Blue for this award.

We'd also like to invite the readers of The Right Blue to click over to our friends Pua and Keoki's blog, Best Hawaii Vacation, to read Bobbie's guest post, Tips for Watching Sea Turtles in Hawaii. Illustrating the article are two of Bobbie's sea turtle photos, both taken at Puako, Hawaii. (Regular readers of The Right Blue already know something about Puako's sea turtles. If you missed them, please read our stories about Myrtle the turtle and her friends at Puako.)

Wordless Wednesday #24 - A 'Right Blue' Sunset

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Wordless Wednesday #23 - Marlinspike Auger

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Wordless Wednesday #20 - Happy Valentine's Day

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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 #19 - Winter in Hawaii

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Life in Hawaii: A Carnival of Aloha

It has been stormy here in Hawaii for the past several days. But those of us who live here know that after the rain, there's always a rainbow -- quite literally.

We like showing facets of our island home to our readers, and we regularly post articles about Hawaii and photos of the creatures that live here. But there is much more to Hawaii, beyond what we write about.

We'd like to invite our readers to visit the current Carnival of Aloha, a blog carnival hosted by our friend Evelyn at Homespun Honolulu. As always, the Carnival of Aloha features posts by bloggers on several of our islands, and they cover a fascinating array of subjects ranging from local architecture to hula dancers to whales. (Yes, our article about our close encounters with Humpback Whales in Hawaii is included, but there are others, too!) Or maybe you'd prefer to have a look at any of the several articles about interesting things to do, see -- and eat -- here in Hawaii. Take some time to go and have a look at the 6th edition of the Carnival of Aloha: We've Got Us a Whale of a Carnival!

About the Photo: I took the above picture in my back garden early one morning after an all-night rain. We woke up, opened our bedroom blinds and saw this beautiful double rainbow over the Pacific Ocean. I quickly grabbed the point-and-shoot camera that was handy and snapped this image. If you look closely (click the photo to enlarge) you'll see a pair of wild game birds, called Grey Francolins, waiting for their breakfast near our ground feeder.

Tales of Whales: Close Encounters with Humpbacks in Hawaii

I should mention at the outset of this tale that, since Humpback Whales are a protected species, it is unlawful to pursue or otherwise interfere with them, either from the surface or underwater. People, whether on boats or in the water as swimmers or divers, are forbidden to approach "closer than 100 yards of any humpback whale or closer than 300 yards of a humpback mother and calf," according to the law.

On the other hand, the whales themselves are oblivious to (and excused from) such regulations. If they decide to, they are free to approach us, instead of the other way around. And once in awhile they do just that!

As it happens, our very first underwater whale encounter also was the most dramatic. Or perhaps it seems like that because like so many other 'first time' events in life, it left such a vivid and indelible memory.

Jerry and I were diving at Puako, Hawaii near a certain underwater promontory known as Snapper Point. At the top of Snapper Point, a narrow plateau juts seaward like a coral-covered peninsula. The top of the plateau begins at a depth of about 20 meters (65 ft), then the terrain slopes down steeply to a depth of nearly 40 meters (130 feet), where it levels off, more or less, into a sand flat. It always has been a favorite dive: Swim from shore directly to the base of Snapper Point, have a look around at the sand community for a few minutes, then begin a gradual ascent along the steep and rocky slope to the plateau, finally moving across the coral gardens toward the shallows and shore. It's a classic multi-level dive.

Because Snapper Point is sort of like the last outpost between the shore and the deep blue abyss, we often see big animals there. Sharks, eagle rays, mantas, amberjacks, barracuda, tuna and assorted pelagics cruise past Snapper Point frequently. We also see pods of dolphins in the area from time to time, and sometimes they see us, too, and dive down to look us over. In fact, the possibility of seeing big stuff is a main attraction for diving at Snapper Point.

Then one day at Snapper Point we saw the biggest of the big stuff.

On the day of our first whale encounter, we had completed the deepest part of our dive at Snapper Point, and we were coming slowly up the slope, poking lazily along, looking for shells and little critters on the rocky bank. Just like always.

We were a few meters below the level of the plateau when a shadow passed over us. We both stopped and looked up at the same moment -- just in time to see a full-grown Humpback Whale do a jackknife dive from the surface and glide down toward us. We were stunned.

The whale, which looked to be about the size of a city bus, leveled off just at our depth, at a spot maybe five meters in front of us. It stopped and held its position for a moment, pectoral fins akimbo, and with an eye the size of a basketball, it just looked right at us. I think we actually stopped breathing for a moment, and I'm sure that our eyes, too, were about as big as they could get!

Next the whale drew its pectoral fins in to its sides, banked slightly to its right, and began to glide away. Only when it completed its turn toward the blue did it move its huge tail to propel itself. The last we saw of it was the white undersides of its enormous tail flukes -- easily 10 or 12 feet wide (although we didn't exactly get to measure!) -- beating up and down gently but purposefully as it left us.

That was the end of that dive for us. We could think of nothing but the whale, so we ceased our underwater sightseeing for the day and headed toward the shallows and our exit point.

One of the most striking things about that encounter, beyond the fact that the whale came so close to us in the first place, was noticing how graceful and agile it was. You'd think an animal so large would just lumber about -- a bull in a china shop, as it were. What we saw suggested anything but clumsiness. The whale dived just as deep as it needed to in order to inspect us. Then it paused, motionless, with what any diver would recognize as excellent buoyancy control. And when it left us, it made what can only be described as a precision departure. No thrash, no clunky moves. Clearly it was exquisitely aware of -- and in control of -- its body position, and that of its fins and tail flukes. That is what was so impressive, and what burned into our memory.

While that was our most dramatic whale encounter, it was not the last. On a number of occasions since then, we have seen whales underwater. Most encounters have happened while we were in buoy mode (which I described in the previous whale post), positioned near a dropoff or near the top of Snapper Point, just waiting (and hoping) for the whales to pass by. Very often we would wait like that -- sometimes for up to an hour -- and see nothing but little fishies, or perhaps a manta as a consolation prize. But once or twice in a season a whale or two will swim past us at relatively close range, as if rewarding us for our dedication and patience.

Do they notice us? I have to say, yes, I believe they do. In some instances I have been completely certain that they noticed us. An example that comes to mind right away: Along with our friend Dan, we had spent about forty minutes one day, waiting in buoy mode over a certain dropoff, because we'd seen whales on the surface in that area, just as we were entering the water. It was a cold day, and eventually Jerry signaled that he was going to end his dive and swim to shore because he was too chilled. Dan and I were getting cold, too, but decided to remain at the dropoff awhile longer. Several more minutes went by, and then along came a pair of huge Humpbacks. They swam past, close enough that we felt turbulence. It was really exciting. Spontaneously and in unison, both Dan and I were 'punching the sky' in delight. And believe it or not, one of the whales slowed slightly and looked back at us momentarily, as if to say, "What in the heck is THAT?!"

We have learned something about when to expect a whale encounter, or more correctly, when not to. We have noticed that when we hear the whales vocalizing, we never see them, even when the sounds are so loud that we imagine they must be just feet away. Without exception, every time we have come face to face with a Humpback underwater, it has been during an interval of whale silence. We think, perhaps, that they just don't vocalize much while they are swimming. Of course, neither do we.

About the Photo : I've never been able to photograph a whale underwater. Either I haven't had a camera when the whales appeared, or else I had a camera but it was set up for macro. I chose the photo above from the NOAA Photo Library. According to the notation there, the photographer was Dr. Louis Herman, who has had a long career studying the behavior, sensory processes and cognition of cetaceans. It seems fitting that we use Dr. Herman's photo to illustrate our story: When I was a graduate student at the University of Hawaii (UH), several visits to the Kewalo Basin Marine Mammal Laboratory in Honolulu, which Dr. Herman founded, gave me my first exposure to cetacean behavior. Dr. Herman is now a Professor Emeritus at UH.

Note: This is the third post in a series about the Humpback Whales that winter in Hawaii. In case you have not seen them, you may want to have a look at the two earlier episodes:

• Tales of Whales: Humpbacks in Hawaii - includes a brief video of the whales, plus a link to a live web cam at Puako, where we dive. You may be able to see the whales for yourself if you are lucky!
• Tales of Whales: Vocal Visitations - tells of hearing the whales underwater, and includes a link so that you can listen to the whales' songs and vocalizations, just as we hear them underwater.
  

Tales of Whales: Vocal Visitations

Yesterday we introduced our readers to Hawaii's humpback whales (Megaptera novaeangliae), the huge marine mammals that frequent our waters in large numbers every year during the winter months. At this time of year, the whales' presence dominates in this part of the Pacific Ocean. Not only do we see them daily from the surface as they spout, breach, and slap the surface of the water with their fins and tail flukes, we hear them incessantly beneath the ocean's surface. And sometimes, if we are lucky, we see them underwater as well.

Mostly, we hear the whales. The term whale songs has been used for years to describe the humpbacks' vocalizations. At times they do indeed 'sing', but believe me, a lot of what we hear from the whales is not exactly melodious. They snort, they whine, they trill, they grunt and groan. They make assorted barnyard sounds.

They say "whoop, whoop, whoop" and then purr so loudly that the sounds resonate in a diver's body. When the whales are relatively close by, we can physically feel the sound waves their vocalizations generate, perceiving them as palpable vibrations in our own rib cages, in addition to hearing them.

We think of these events as vocal visitations by the whales. The term 'visitation' may suggest something akin to a spiritual experience in your mind. Without exaggeration, that is what the term is meant to evoke. It's impossible to experience these visitations without having an exquisite sense of awe, in the purest meaning of the word, and without feeling very privileged indeed.

Many, many times during our winter dives at Puako, the whale sounds have been so loud and persistent that they are completely distracting. At their loudest, the sounds are close to overpowering.

At such times there is really nothing to do but to settle on a sand patch somewhere to be still and just listen, because it's impossible to do or think of anything else. If there is nowhere safe or convenient to settle, we take up a posture that we call 'buoy mode,' which Jerry is demonstrating in the photo on this page. Buoy mode entails positioning oneself in the water column, suspended somewhere below the surface, but well above the bottom. The idea is to remain quiet and immobile. In this case we use buoy mode to listen to the whales in a kind of motionless meditation.

Sometimes we hear the calls of an individual whale. More often we are party to what clearly are conversations amongst a number of whales. But, almost without exception, every time we actually have seen whales underwater, the encounter has occurred during a period of silence on the part of the whales. Then out of the blue -- very literally in this case! -- there's a whale (or two or three), right before our eyes.

We'll tell you about some of our face-to-face encounters with humpback whales in Hawaii in our next regular post (after Wordless Wednesday!), but meanwhile we encourage everyone to visit The Whalesong Project to listen to the kinds of whale vocalizations that we hear all winter when we dive at Puako. When you get to the website, click on the phrase "We are bringing Whalesongs to the World" near the top of the page. Let the recording load in your favorite media player, and then sit back, close your eyes, and experience a humpback whale vocal visitation for yourself.

Tales of Whales: Humpbacks in Hawaii

One of the most wonderful -- and wondrous -- things about diving here in Hawaii, is the fact that some 10,000 humpback whales (Megaptera novaeangliae) spend the winter months in our waters. During the winter months, we get to see them frequently on the surface, and once in awhile, underwater as well.

Our blogger friend Sheila put up a humpback whale video on her site yesterday, and it reminded us to share some whale tales with our readers. For openers, here's the video:



(If the video does not play or display properly above, click here to view it on YouTube.)

The humpbacks that come to Hawaii every winter are a part of the North Pacific population that spend their summers in Alaskan waters. They pass the summer feeding, mostly, and then migrate south to warmer waters in winter. Some of these whales winter in the eastern Pacific, near Baja California, while the rest come here to Hawaii. It is here that they mate, and where the mama whales who successfully mated the year before give birth to their calves.

The whales begin arriving for the season in late Fall. We usually spot the first ones some time between Thanksgiving and Christmas. The arrival of the whales is a big deal to those of us who live near the coast or spend time in the water. Neighbors vie to be the first to spot the whales as they arrive, and to spread the word, "They're here! They're here!"

We see them offshore frequently, throughout the winter. We see them spout when they come to the surface to breathe. As mammals the whales are air breathers, and even though they can hold their breath for quite a long time, they must come up to the surface regularly for air.

The humpbacks play near the surface, too. They slap the surface of the ocean with their tail flukes, or with their big, flat pectoral fins. They breach and frolic with one another. Quite often we see the mama whales with their youngsters breaching almost simultaneously -- a real sight to behold!

These are huge creatures, weighing over 40 tons at adulthood. Despite their mass, they are very agile in the water. In the video you'll see one whale manage to leap almost completely out of the water. We call that maneuver a "full pickle" -- a term based on an apt description we once heard: that the humpback whale sort of resembles a huge dill pickle, with ceiling fan blades for pectoral fins. I can't recall exactly where we heard that, but the image stuck, and we began referring to a full breach as a "full pickle."

Here's a link to a live web cam at Puako, where we dive most often, so you can see what we see from the shore. If you're lucky, you just may see some whales. (You can also see what our weather and ocean surface conditions are like, in real time!)

In the next post we'll tell you about some encounters we've had with humpback whales. Meanwhile, you can find out more about these incredible creatures at these recommended websites:

• Hawaiian Islands Humpback Whale National Marine Sanctuary - NOAA
• Getting to Know the Humpback Whale - The Dolphin Institute

Next: Encountering humpback whales underwater.

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

My previous Wordless Wednesday posts.

Wordless Wednesday home page.

Wordless Wednesday #9 - November 28, 2007

[Click photo for larger view.]

My previous Wordless Wednesday posts.

Wordless Wednesday home page.

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.

Wordless Wednesday #8 - Happy Thanksgiving