Happy Holidays from The Right Blue


We wish all of our readers a happy, festive and safe holiday season. We're taking a break for the holidays, but we hope to see all of you again early in the new year. We have a few surprises in store for our readers in 2010. Meanwhile, stay well and enjoy yourselves.

Happy Holidays!

Bobbie & Jerry

Labyrinthine brain coral

brain coral

What: Macro photo of the surface of a Labyrinthine brain coral (Diploria labyrinthiformis).
The polyps, which usually extend at night, live in the 'valleys' between the ridges.
These corals form hemispherical heads that can grow to four feet in diameter.

Where: I photographed this coral off the coast of Grand Cayman.  This species is found throughout the Caribbean and is also found around the Bahamas and south Florida.

Wreck diving: Beware of entanglement

wreck diving

by B. N. Sullivan

What:  This photo of Jerry ascending from a wreck dive is a reminder that the potential for entanglement is one of the hazards of diving on natural wrecks.  Wrecks that have been intentionally sunk as artificial reefs and diver playgrounds usually are prepared ahead of time to minimize hazards that could lead to diver entanglement or entrapment.   Doorways and portholes are removed or welded open, and cables, lines, and other sources of entanglement are taken off the vessel.  This is not the case with natural wrecks, i.e., vessels that have sunk as a result of an accident, or war.  Proper training in wreck diving will educate the diver about how to recognize and cope with the risks entailed in diving on natural wrecks.

Where:  I took this photo of Jerry at the site of the wreck of the Zenobia, a modern ship that sank in 1980 off the coast of Larnaca, Cyprus.  The Zenobia was a huge vessel, more than 172 meters (560 feet) in length, with a beam of about 23 meters (75 feet).  Click here to see a photo of the Zenobia, just before she sank.

We made a number of dives on the wreck of the Zenobia in the 1990s.  In case you missed our series of articles about those dives (with photos), here they are:

The Octopus: Nature's ultimate shape shifter

by B. N. Sullivan

We have encountered octopuses frequently wherever we have dived, and they are fascinating creatures to observe underwater. They can change their coloration and the texture of their skin readily to camouflage themselves.  Take a look at the above image of a Caribbean Reef Octopus (Octopus briareus), which I photographed in the Cayman Islands. It can change its skin color from a dark reddish shade to the almost iridescent green you see here.  The skin texture can change from smooth, to rough or prickly looking to mimic the surface texture of the rock or coral on which the octopus is resting.

Octopuses also can squeeze through incredibly small spaces, since they have no skeleton, either internally or externally.  We have seen these creatures slide their bodies between lobes of coral that were practically touching each other, and flatten themselves to pass through a crack in the wall of a cavelet. It's a most amazing sight -- almost magical.

I recently discovered the video below on YouTube.  It had no accompanying explanatory information other than its title -- "Octopus escaping through a one inch hole" -- but it appears to be an experiment to illustrate the shape shifting ability of the octopus. At the beginning of the video, the octopus is inside what looks like a clear lucite box.  In the course of the next 30 seconds, the octopus manages to extricate itself from the box by passing through the round hole in the side of the box -- and quite effortlessly at that.

Watch the video and you will  see why we think of the octopus as Nature's ultimate shape shifter!

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

Hat tip to YouTube user defosterr, who posted the video to YouTube three years ago.

Bet you can't eat the whole thing!

Chromodoris quadricolor

What: A Striped Pajama nudibranch (Chromodoris quadricolor) browsing on a brightly colored sponge (Negombata sp.), which is the favorite food of this nudibranch species.

Where: I photographed this nudibranch in the Red Sea, at Tiran Island.

Seeing stars: A new descriptor for Linckia sea stars?

by B. N. Sullivan

Linckia sea stars all have plump, cylindrical arms, making the genus easy to recognize.  Earlier this month we posted a photo of a purple sea star, Linckia multifora.  Our fellow diver and underwater photographer Andrew Cooper commented that, to him, Linckia sea stars look like something a five year old would make out of Play-Doh.  We instantly liked that description --  it struck us as particularly apt.

So, here are two more examples of what we shall think of henceforth  as the Play-Doh sea stars, thanks to Andrew. (Check out Andrew's blog, A Darker View.)

The sea star in the first image below is Linckia laevigata.  The sea star in the second image probably is L. multifora (but we couldn't swear to it).  Both were photographed at Indonesia's Bunaken Marine Park.

Linckia laevigata

Linckia sp.

Serene Waipiʻo Valley on Hawaii's Big Island

Waipiʻo Valley

by B. N. Sullivan

This is the mouth of the Waipiʻo Valley, situated on the northeastern coast of Hawaii's Big Island, in the Hamakua district.   The remote valley is historically important as the childhood home of King Kamehameha I, but we think its greatest virtue is its stunning natural beauty.  The valley is about a mile wide at the coast, and is surrounded by steep cliffs that rise up to 2,000 feet from the valley floor.  Waipiʻo Valley extends inland for roughly five miles, and features hiking trails, streams, and waterfalls -- including  the 1,300 foot high Hiʻilawe Falls.

This photo was taken from the Waipiʻo Valley Overlook.  From this vantage point you can see the surf breaking on the black sand beach that forms the seaward edge of the valley.  The Overlook is near the top of the narrow, rugged road that descends into the valley.  Not only is the sole road into Waipiʻo Valley narrow, it is very steep -- a 25% grade -- requiring four-wheel drive.  It takes about a half hour to carefully descend into the valley from this overlook point.

As residents of Hawaii's Big Island, we may be prejudiced, but one thing we can say about our island home is that it's a feast for the eyes, don't you think?

Seeing stars: Linckia multifora

Sea Star (Linckia multifora)

What: Sea star (Linckia multifora), family Ophidiasteridae. Common names include: Spotted Linckia; Multi-pore Sea Star; Multicolor Sea Star.

Members of this genus have cylindrically shaped rays, and skin that has a rough, granular surface.
They come in a variety of colors.

Where: I photographed this sea star on a reef at Bunaken Marine Park, Indonesia.

Seeing stars in the sea

by B. N. Sullivan

Awhile back we had some fun with our 'Every Seashell Has a Story' series, in which we presented photos and tales of marine molluscs that produce and live in shells.  Another interesting and often very pretty class of marine animals are Sea Stars -- also known colloquially as 'Starfish' (although they really are not fishes, of course).

Sea Star (Fromia monilis)
Sea stars are marine invertebrates that belong to the phylum Echinodermata, which also includes brittlestars, urchins, and sea cucumbers.  Sea stars make up the class Asteroidea.

Although the sea stars we have come to know best live in tropical reef environments, sea stars can be found in all the world's oceans and seas.  There are about 1,800 sea star species worldwide.

The pretty sea star pictured on this page has quite a few common names: Mesh Sea Star, Tiled Starfish, Necklace Sea Star, and Peppermint Starfish.   (Choose which one you prefer!).

Its scientific name is Fromia monilis, and it is a member of the Ophidiasteridae family. This is an Indo-Pacific species widely distributed in the Western Pacific and also common in the waters around Indonesia. The ones here were photographed at Indonesia's Bunaken National Marine Park.

The classic, prototypical sea star has a central disc shaped body from which five rays (i.e., arms) radiate. While that may be the idealized form that comes to mind when we think of sea stars, in fact there are many species that have more than five arms.  Some sea star species have a body that looks less like a disc than a sort of lump where the rays appear to converge; others have a large body disc and rather stubby arms.

Sea Star (Fromia monilis)
The rays have rows of little tube feet on their undersides.  (We'll show you some macro images of those in a forthcoming post.).  A sea star's mouth also is on its underside, in the center of the body, while its anus is on the top (aboral) side of the body disc. The external covering, or skin, of sea stars can be leathery, or fuzzy, or warty, or prickly.

Did you know that sea stars operate hydraulically?  On the top side of the disc is a structure called the  madreporite, which includes an opening -- a pore -- through which the sea star draws in water to its hydraulic vascular system. The sea star's respiration, feeding and movement all are powered by its hydraulic vascular system. If you look closely at the second photo on this page, you can see this sea star's madreporite. It is that little bump that looks a bit like a pimple, to the right of center on the red disc. [Click on either photo to enlarge.]

What do you think when you see the ocean?


by B. N. Sullivan

When you see a scene like the one in the photo above, what do you think? Do you want to go for a swim? ...grab your mask and snorkel? ...put on your dive gear? Or maybe you'd think about getting into a boat and heading out to sea?

Would you muse about all the places and possibilities that lie over the horizon? Or would you feel like you had arrived at some kind of dead end?

That's right, I said dead end!

How people feel when they arrive at a shoreline is completely dependent on their point of view. Let me tell you a story that taught us that this is so.

A number of years ago, while traveling in Greece, we agreed to give a ride to a young man who was headed our way. We didn't know him very well, but we learned something important from him when we stopped for a bite to eat. We chose a seaside taverna in the little coastal town of Kamena Vourla. The taverna had a canopied outdoor section with tables and chairs placed right on the beach, and that's where we sat. It was a fine sunny day, with a light sea breeze wafting the salty air and causing little wavelets to lap against the shoreline. It was quite heavenly, actually.

We ordered our lunch, and then sat there chatting while we waited for our food. We swapped stories about our travels -- places we'd been, and places we'd still like to visit. Then, enchanted with the lovely Aegean coastal scene and the pleasantly moist sea air, I gushed, "Don't you just love being next to the sea like this? I always feel like the whole world is out there, just waiting for me!"

The young man gave me a puzzled look and replied, "Really? How odd. When I get to the seacoast I always feel a bit sad, because I know that's as far as I can go."

It was my turn to look puzzled. Never before had I heard anyone equate a seacoast with the end of the line -- an impediment, rather than an opportunity. I felt my expansive mood drain away, replaced by a sense of confusion. This really was a new one on me, so I felt compelled to probe, to try and figure it out.

Further conversation revealed that the young man had never been on a boat, much less a ship. He did not know how to swim, and in fact he was afraid of the water; he told us one of his worst fears was that he would drown some day. Once he revealed all that, his view regarding the seacoast made a bit more sense (although we felt quite sorry for him).

The lesson, of course, is that how we feel about places and situations depends entirely on our own point of view -- and that, in turn, often arises from our personal experiences (or lack thereof).

So, when you are on the coast and looking seaward, which is it for you? Is it the beginning of the rest of the world, or is it merely the end of the road?

About the photo: This is our favorite entry point for shore dives and snorkeling at Puako, Hawaii.

Butterflyfishes on a North Kohala reef

by B. N. Sullivan

Of all the reef fishes in Hawaii, those that belong to the Butterflyfish family (Chaetodontidae) are perhaps the most colorful and easy to recognize.  About two dozen species of butterflyfishes live in the waters around the Hawaiian Islands.  The photo at right shows two of those species. [Click on the photo to enlarge.]

This photo is dominated by a grouping of Pyramid Butterflyfish (Hemitaurichthys polylepis).  Their common name refers to the triangle-shaped white patch  that covers most of their bodies.  These plankton eaters tend to aggregate over stands of coral during daylight hours, just as you see in the photo.  Pyramids are native to the central and western Pacific Ocean.

In the lower left quadrant of the photo are some Milletseed Butterflyfish (Chaetodon miliaris), named for the vertical rows of black seed-like dots on their otherwise yellow bodies.  They also sport a prominent black ocular bar (eye-stripe) and a black blotch at the base of their tails (i.e., the caudal peduncle).  They, too, eat plankton, but sometimes a diver or snorkeler will see a Milletseed Butterflyfish cleaning other fishes.

The Milletseed Butterflyfish is a Hawaiian endemic species -- that is, they are found naturally only in the Hawaiian Islands.  They are quite plentiful along coastal reefs, so if you snorkel or dive in Hawaii, you are very likely to see these fishes.

The photo on this page was taken at Big Sandy, a dive site located a few miles north of Kawaihae, on the North Kohala Coast of the Big Island.

Humpback whales returning to Hawaii for the winter season

by B. N. Sullivan

We're at the start of Humpback whale season here in Hawaii. Every autumn, large numbers of Humpbacks (Megaptera novaeangliae) migrate from their summer feeding grounds in the north Pacific to the waters around the Hawaiian Islands, where they then spend the winter. Those of us who live in Hawaii tend to feel a bit possessive about the north Pacific stock of Humpbacks, because they are born and bred in our waters.  Over the course of their winter stay in Hawaii, the big cetaceans mate, and the females who became pregnant the year before give birth to their calves.  In spring they all migrate north again

Although we haven't yet seen this year's Humpbacks here on the Kohala Coast of the Big Island, the first whales of the season were spotted recently near Maui. That means we can expect to see them here on our coast any minute!

Earlier this month some lucky folks on an Oceanic Society whale watching boat near the Farallon Islands, 25 miles west of San Francisco, had an amazing encounter with some Humpbacks. Four friendly whales "approached the boat and for over an hour circled the boat, nearly brushing up against it, and seemed to make contact with the 45 passengers on board."

Here is the Oceanic Society's video of that exciting encounter:

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

Hawaiian Green Sea Turtle at Honaunau Bay, Hawaii

by B. N. Sullivan

Here is a large image of a Hawaiian Green sea turtle (Chelonia midas) -- posted back-to-back with our previous post of a Hawksbill turtle (Eretmochelys imbricata), so that our readers can compare the features of the two species. Like the Hawksbill in the previous photo, this Hawaiian Green also was photographed at Honaunau Bay on the southeastern coast of Hawaii's Big Island, however the photos were taken on different days.

A Hawksbill at Honaunau

WHAT: Hawksbill Sea Turtle (Eretmochelys imbricata) - Hawaiian name: Honu'ea

WHERE: I photographed this turtle at Honaunau Bay, on the southeastern coast of Hawaii's Big Island.

Hawksbille Sea Turtle (Eretmochelys imbricata)

We see this species of sea turtle infrequently in Hawaii, so it's always nice to cross paths with one. Hawksbills have been known to nest on the eastern coast of the Big Island, but they are not plentiful. Seeing one on the western coast of the island always is an event worth noting.

Unlike the Hawaiian Green Sea Turtles, which are primarily vegetarians, Hawksbill turtles eat sponges and small invertebrates in addition to algae.  We  have not observed Hawksbill feeding behavior in Hawaii, but elsewhere we have seen them munching soft corals and sponges.  We once spent most of a dive watching as a Hawksbill turtle methodically devoured a tube sponge, gnawing it and pulling away hunks until there was nothing left of the sponge but a stub!

For more information about this endangered species, visit the U.S. Fish and Wildlife Service Hawksbill Sea Turtle Fact Sheet.

Allya, a captive Beluga whale that blows bubble-rings

Meet Allya, a Beluga whale (Delphinapterus leucas) who lives at an aquarium in western Japan. Like the dolphins at Orlando's Sea World, Allya has learned to blow bubble rings.

The YouTube blurb for this video notes:
Allya clearly loves interacting with her audience. She aims the bubbles at spectators as they peer in through the glass.
To learn more about this species, visit the Beluga Whale Fact Sheet on Web site of the American Cetacean Society.

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

Thanks to the folks at itnsource.com for this video.

Gray Angelfish (Pomacanthus arcuatus)

What: Gray Angelfish (Pomacanthus arcuatus), a common angelfish species in the Caribbean Sea.
This adult specimen was approximately 40 cm (16 in) long, from nose to tail.

Where: I photographed this Gray Angelfish at Cayman Brac, Cayman Islands.

Click on the photo to enlarge.

Helping kids learn about the ocean

by B. N. Sullivan

We began publishing our photos and stories on The Right Blue back in mid-2007 primarily as a means to share them with our family and friends. Since then, we have acquired a much larger audience than we ever imagined. These days, our regular readers are divers, marine scientists, and ocean buffs of all stripes -- including children.

From time to time we hear from kids -- or their parents.  They thank us for an article about something they were studying, or ask if we know where to find more information about a certain creature .  Sometimes they want to know if they can use one of our photos for a report or a school project.  We're always glad to help if we can, because we believe it's important to share with children our  fascination for all things ocean.  We like to foster young people's  interest in the sea and understanding of marine ecosystems.

Earlier this week our fellow ocean bloggers over at Deep Sea News came up with a great idea. They proposed that we, along with a number of other ocean and nature bloggers, join together to sponsor ocean and waterway science education in K-12 classrooms. We're doing this by publicizing and promoting Donors Choose, a charity that allows individuals to directly fund educational projects proposed by K-12 teachers themselves.

The teacher-chosen projects we are sponsoring are all worthy. Teachers at  participating schools in seven states around the U.S. are asking for things like materials for classroom projects; a salt water aquarium; gear to help them collect field samples; subscriptions to a student science magazine; and transportation for a field trip to learn about what sailors and explorers did 'back in history'.

We are joining the guys at Deep Sea News, Southern Fried Science, Blogfish, Oyster’s Garter, Echinoblog, Cephalopodcast, Drop In, The New Blue, Natural Patriot, and Malaria, Bedbugs, Sealice, and Sunsets in asking our readers to help fund these educational projects for young people by making a donation. The requests from the individual teachers are modest, so even a $10 donation will be helpful -- but of course more generous donations also are very welcome!

Follow this link to Donors Choose to have a look at the individual projects. You can specify which project you'd like to help fund, or you can make a general donation via the "Give to the most urgent project" button near the top of the list.

One more thing:  If you have a blog or a website and would like to join our group in supporting and  promoting these projects, let us know.  We'd love to have you on board.

Threadfin Butterflyfish (Chaetodon auriga)

What: Close-up photo of a Threadfin Butterflyfish (Chaetodon auriga), an Indo-Pacific species

Where: This fish was photographed at Honaunau Bay, on the west coast of Hawaii's Big Island.

Click on the photo to enlarge so you can see the details.

Nudibranchs in The Right Blue

Chromodorid nudibranch
Nudibranchs-- also called sea slugs -- are marine gastropod molluscs (snails) that do not have a shell. (The name 'nudibranch' means bare gills.)  Most tropical nudibranchs are small and brightly colored, so they are a popular  subject for underwater macro photography.

Here is a directory of articles about nudibranchs in The Right Blue:

Here is a directory of nudibranch photos on The Right Blue, sorted alphabetically by family name and species name:

  • Gold Lace nudibranch (Halgerda terramtuentis), Hawaiian endemic species, two macro photos - Pacific: Puako, Hawaii
  • Dotted Sea Slug (Peltodoris atromaculata), three macro photos, incl. feeding behavior - Aegean Sea: Greece

Nudibranch video:
  • Spanish Dancer (Hexabranchus sanguineus), shows how the creature 'swims'

Knock-knock: Who's there? A surprise from the past

by B. N. Sullivan

When I used to shoot film underwater, I made it a habit to mark a code number on the frame of each of the slides as soon as they had been developed.  The coding system I devised long ago consists of a number that corresponds to a particular entry in my dive logs -- that identifies the when and the where -- plus a letter code that indicates something about the subject.

Jerry finished scanning all of our old underwater photography slides awhile back, and as he went along, he labeled each with its original ID number and sorted the scanned images into folders according to the subject code on the slide.   I still have not finished reviewing all of the thousands of images, but every once in awhile I sit down in front of the computer and spend the next few hours sifting through those digital files.

So, there I sat earlier today, looking at images filed in the 'Sponges' folder, and I found this photo.  Looking first at the thumbnail image, it appeared to be a close-up photo of the surface of an orange sponge -- no more, no less.  Then I loaded it into the photo editor to have a closer look at the full-screen version.  Do you see what I saw?

There, peeking at the camera from an excurrent opening of the sponge is a little fish!  (I can't decide whether the fish looks surprised or merely annoyed.)

The next surprise for me came when I looked up the numerical code in my log books.  I was amazed to discover that I had taken this photo in 1990, during our first-ever dive trip to the Cayman Islands!  According to my log book notes, that roll of film was shot at a place called Angelfish Reef, Grand Cayman.

I have no idea what species of sponge that is, nor do I know the identity of the little fish. My best guess is that it is some kind of Blenny.  It's about the right size, and many fishes in that family like to hide out in small holes in the reef with only their heads visible to passers-by.  In any case, we're glad to give him a new home in our underwater menagerie here on The Right Blue.

Oh, Baby! A juvenile Scorpionfish

by B. N. Sullivan

See that little fishie in the photo at right?  It's a juvenile scorpionfish -- species unknown.

We came across this little guy in the Red Sea during a night dive at a place called Tiran Island,   in the Straits of Tiran.  (For those of you who may be a bit foggy on Red  Sea geography, the narrow body of water that separates Egypt's Sinai Peninsula from Saudi Arabia is known as the Straits of Tiran. That is also where the Gulf of Aqaba joins the rest of the Red Sea.)

We were there to photograph other critters -- which we did --  but once we spotted this little baby, it became the highlight of our dive.  I was kneeling on the sand, fiddling with camera settings.  Jerry shined his light onto my camera so that I could see what I was doing.  In the periphery of the pool of light, we saw something move.  That something was partially covered with sand, but it had some colorful bits sticking out of it.  It looked a little bedraggled, but we recognized that it was a tiny fish.  Those colorful bits turned out to be its tail and pectoral fins.  

This next photo shows how the little fish looked when we first saw it lying on the sand.  Not quite two inches (5 cm) long, we knew it was some kind of fish, and that it probably was a juvenile.  But a juvenile what??

Jerry slid his gloved hand under the little critter, picked it up,  and held it out to me.  We shined our lights on it to get a better look, when all of a sudden it wiggled, then fluttered, launching itself from the palm of Jerry's hand into the water column like a fledgling bird leaving its nest.

Luckily, I was able to snap a few frames of the fish as it glided back down to the sand (see first photo).  By this time we were both quite sure it was some kind of scorpionfish, based on its overall shape, but to this day we do not know which species.

Our best guess is that it is a baby Bearded Scorpionfish (Scorpaenopsis barbatus), a species that is plentiful in that area of the Red Sea.  The adults have an overall shape similar to the juvenile we saw and photographed that night.  We have shown the photos of the juvenile to a number of people who know something about Red Sea fishes, but so far no one has been able to identify it with certainty.   If any readers of The Right Blue happen to know the identity of this juvenile, please do let us know.

For reference, here is a photo of an adult Bearded Scorpionfish from the Red Sea.  This specimen was photographed in the central Red Sea at Little Brother (Brothers Islands), where it was trying its best to blend into the reef scenery.

Video: Making of 'The Abyss'

One of our favorite sci-fi movies is The Abyss. This video gives an idea of why the film became known in the industry as "the toughest shoot in film history." The video runs for nearly 10 minutes -- much longer than the videos we usually post here on The Right Blue -- but it is both entertaining and informative, and we think it's worth the time it takes to watch.

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

Stalking the wily night critters: Hinge-beak shrimps

by B. N. Sullivan

Hinge-beak shrimp
Imagine that it's just after dark.  You jump off the stern of the boat into the water and descend to the reef.  You switch on your light and sweep the beam  left and right to get your bearings.  You see little blinking red lights all over the place. What the...??

Don't be alarmed.  Aliens have not landed and dispersed on the reef.  What you probably are seeing are reflections from the eyes of tiny critters called Hinge-Beak Shrimps.  All of the shrimps in this family have big googley eyes that reflect when a beam of artificial light is shone on them.

These creatures of the night are little guys, usually between 3 cm to 5 cm (1.25 in to 2 in) in length. They hide all day -- who knows where?  At night they come out to feed,  often in large numbers, but they're not easy to find then either.  Oh, you definitely will see those blinking red lights I mentioned, but if you try to find the actual critter behind the pinpoint of red light you will be unsuccessful much of the time.  These critters are extremely shy, so as soon as you get near -- piff! -- they're gone!

I had wanted to photograph one of these critters for years before I finally managed to do so.  I succeeded in capturing the macro image you see on this page by concentrating very, very hard on where one of those red dots of light seemed to be, then switching off my light and sneaking up to the presumed spot.  In this instance, the tiny red light  seemed to be coming from a pencil urchin, so I assumed the shrimp was hiding among the urchin's thick spines.  I  knelt down very close to the urchin while Jerry shone a small light beam near to it, but not on it, giving me just barely enough light to set up the shot.  I pressed the shutter release and  voilà! Gotcha!

Now, about that funny name, Hinge-beak shrimp.  Shrimps in this family (Rhynchocinetidae) have a beak-like rostrum that can bend.  In fact, the name Rhynchocinetidae actually means 'movable beaks'.  Other kinds of shrimps do not have this feature.

We first encountered these shrimps in the Caribbean Sea where the dive guides called them Red Night Shrimps.  It turns out that the shrimps' bodies are mostly red, but that name referred to the red glow from their eyes at night.  We have since seen species from this family almost everywhere we have dived around tropical reefs at night: Caribbean, Red Sea, Hawaii, and throughout the Indo-Pacific region.  Each locale seems to have its own common name for the creatures in this family.  We think the name Red Night Shrimps really suits them, so that is what we like to call them.

Green sea turtle (Chelonia mydas) at a cleaning station in Hawaii

Look what Jerry found on Google Earth!

We have mentioned cleaning stations in several of our blog posts. Here is a short video of a Hawaiian Green Sea Turtle (Chelonia mydas) being 'serviced' at a turtle cleaning station on the Big Island's Kona Coast. Visits to these cleaning stations are the turtle version of going to a beauty salon for a spa treatment. The turtle looks like she's saying, "Ahhh" -- don't you think?

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

Goatfish: Tropical bottom-dwellers

by B. N. Sullivan

Take a close look at the photo on this page, and you can understand how this fish family acquired the common name Goatfish.  Members of this family (Mullidae) all sport appendages on their chins that look like very fat whiskers.  As the story goes, these 'whiskers' suggest a billy-goat's beard.

Those appendages are called barbels, and they are a kind of sensory organ.  They sense chemical 'smells' and a goatfish uses its barbels to help it locate a meal.

Goatfish are bottom-dwellers.  They like sandy areas, where they can rummage in the sediment for tasty morsels to eat.  They eat small crustaceans, worms,  snails -- just about any little invertebrate they can find under the surface of the sand.  Some goatfish species also eat tiny fishes; we have seen goatfish use their barbels to nudge little fishies out of their hiding places in reef crevices and then gulp them right down.

Most goatfish species live in relatively shallow water, so it is not uncommon for snorkelers to spot them.  During the day, goatfish often hang out in small groups in sandy areas at the edges of coral reefs, where you might see them lying on the bottom.  Most of their feeding activity takes place at night, but sometimes you might see some goatfish nosing around, looking for food during daylight hours.

Goatfish are quite adept at changing their coloration.  Most assume one color pattern while at rest, and another when swimming.  There are some that even sport a specific color pattern just for feeding!

The fish in the photo on this page is called Forsskal's Goatfish (Parupeneus forsskali), common in the Red Sea.  It is solid-colored during the day, with a very dark stripe on each side that runs the length from its nose, through its eye, and almost to the base of its tail.  At night, while the fish is feeding, the dark stripe becomes blotchy, and the body of the fish is mottled rather than solid.  The photo was taken during a night dive at a reef near Safaga, Egypt. [Click on the photo to enlarge.]

In case you are wondering if these are edible fish, yes, they are.  We've never eaten goatfish, but we have seen some for sale at fish markets in several countries, particularly in Asia. In fact, some of the larger goatfish species look like they could be quite meaty.  If any of our readers have dined on goatfish, we would be interested to know how they tasted, so do tell us.

Invertebrates are such spineless critters!

by B. N. Sullivan

AcroporaReaders of  The Right Blue have been very patient while I turned my attention to 'another blog' for the month of August. (Yes, I feel a bit like I have somehow been unfaithful!)  Never fear: on August 31 I ended my month-long tenure over at Photo Synthesis.  So, dear readers of  The Right Blue, I am all yours again.

In order to tie things up tidily, here are the links to the final two posts that I did over at Photo Synthesis:
Now I have one more thing to tell you about. There is a blog carnival called Circus of the Spineless, "A monthly celebration of Insects, Arachnids, Molluscs, Crustaceans, Worms, and most anything else that wiggles, crawls or fluttered. (Spineless = invertebrates, i.e., critters with no backbones.)

One of the articles I did for Photo Synthesis -- the one about the Bearded Fireworm -- is featured as a part of this month's Circus of the Spineless, which is hosted by Susannah Anderson at her nature blog, Wanderin' Weeta. Do go and have a look at the great collection of photos and articles about all manner of creepy crawly things over there. It's quite an education.

 Thanks, Susannah, for including my creepy crawly Fireworm in this month's Circus.

And now, back to our regularly scheduled programming on The Right Blue...

Who are you calling a worm?!

by B. N. Sullivan

What the heck is that thing? A caterpillar? A centipede? Nope, it's a marine worm called a Bearded Fireworm (Hermodice carunculata). I wrote an article about this critter for Photo Synthesis, and it includes some ultra-close-up shots of this mean-looking creature. Be sure to go and have a look.

Hermodice carunculataLong-time readers of The Right Blue might recognize this creature. H. carunculata was the 'model' for an article I wrote back in 2007 about photographing critters on different backgrounds. The one pictured here, at right was, was photographed in the Aegean Sea, near Cape Sounion, Greece. [Click on the photo to enlarge, if you dare.]

Also posted on Photo Synthesis this past week was an article -- titled Gimme shelter! -- about creatures that live on or among sea anemones and corals for protection. The article is illustrated with some of my photos of clownfish, including the species that was the model for the cartoon movie character, Nemo.

Another Photo Synthesis article was about photographing feeding records of nudibranchs. Readers of The Right Blue already have seen quite a few of my nudibranch photos, I know, but go and have a look there if you'd like to see a few more.

Next was a photo essay featuring Gorgonian sea fans, including macro photos of several different types. Finally, I posted an article about Cerianthid tube anemones on Photo Synthesis, a topic I wrote about here on The Right Blue just about a year ago. Remember Cerianthid Tube Anemones - Flowers of the Deep?

This is my final week of writing for Photo Synthesis. Just a few more posts there, and I will be back to publishing my underwater photos exclusively here on The Right Blue. Stay tuned...

"Does this pose make my butt look big??"

What: The critter asking the question is a Green Sea Turtle (Chelonia mydas).
The diver is Jerry, of course.

Where: I took this photo at Pulau Sipadan, Malaysia.

Chelonia mydas
Click on the photo to enlarge -- turtle butt and all!

Crinoids, fish faces and backscatter - oh my!

CrinoidsBobbie has been busy over at PhotoSynthesis this past week, posting close-up protraits of Wrasses, showing and writing about Crinoids, and suggesting ways for underwater photographers to cope with the problem of backscatter.

What's backscatter, you ask? It's the stuff that all too frequently spoils underwater photos that were taken in water that's not exactly clear. For an explanation, check out Backscatter: The bane of underwater photography, in which Bobbie holds forth about matters of physics and light, but also includes a handful of really nice critter photos.

The photo on this page shows some Crinoids on a reef in the Celebes Sea. Remember them? Long time readers may recall that Bobbie wrote about Crinoids -- also known as Feather Stars -- here on The Right Blue more than a year ago. This week she wrote about Crinoids on PhotoSynthesis, so if you find these Echinoderms interesting, or you like to see pictures of them (including some pretty amazing macros), check out Getting to know crinoids through close-up photography, and then Crinoids on the night shift. (Yep, a two-parter.)

And finally, do have a look at Hello, Fish Face -- four in-your-face close-ups of pretty fishies from the Wrasse family.

Video: Hawaiian Green Sea Turtles

The folks over at JournOwl.com have put together this very nice video about Hawaiian Green Sea Turtles, one of our favorite ocean creatures. The narration of the video echoes much of what we said in our earlier article about Hawaiian green sea turtles.

P.S. There are many more sea turtle articles and photos on The Right Blue.

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

The Right Blue is the 'flavor of the month' at Photo Synthesis

Gymnothorax meleagrisSeveral months ago the folks over at ScienceBlogs.com launched a new project -- a blog called Photo Synthesis. The idea was to showcase science-related photography and provide a platform for discussing it.

Here's how they describe it:
The internet is home to a wealth of captivating science images, from the many microscopic components of a cell to the remote corners of the universe captured by Hubble. On Photo Synthesis, we aim to bring you the best of what's out there. Every month we will feature the work of a different photoblogger, exposing worlds both small and large, familiar and exotic. We will let the power of the lens take us where we ourselves are not able to go.
Shortly after Photo Synthesis was launched, we were asked if we would like to take a turn there. Long story short: Bobbie agreed to post some of her underwater photos there, and to write about the photo subjects and the process of taking pictures underwater -- just like she does here on The Right Blue.

This month -- August -- is Bobbie's month at Photo Synthesis, so we'd like to invite our readers to visit there and say hello. Just think: If you like what you see at The Right Blue, this month you can have a double dose!

Here's the link to Photo Synthesis, and here is what Bobbie has posted there so far:We'll keep you posted on what else Bobbie publishes at Photo Synthesis.

About the photo on this page: Bobbie photographed this Whitemouth Moray eel (Gymnothorax meleagris) in its hiding place in a bed of Plate-and-Pillar Coral (Porites rus) at Honaunau Bay, Hawaii.

Leviathan cowries: Becoming scarce in Hawaii?

by B. N. Sullivan

Cypraea leviathan
Here is another favorite from our seashell collection. One of the larger cowries found in Hawaii, its name is apt: Leviathan (Cypraea leviathan).

This one has been in our collection for a long time. I found it in the mid-1980s at Pupukea on the north shore of the island of Oahu. This one is 6.6 cm in length (roughly 2.5 in).

We used to see Leviathan cowries quite regularly, but we haven't seen any at all in quite awhile, alive or empty. These guys live in relatively shallow water, so they are (or were) relatively easy for snorkelers, divers -- and even waders -- to spot. We fear that we're not seeing them these days because too many live ones have been taken by collectors, leaving too few to reproduce and maintain the population.

Older reference books about seashells list Leviathan cowries as endemic to Hawaii. More recently these shells have been recorded in a number of other locations in the Indo-Pacific region, so while we still can say that they are indigenous to Hawaii, they are no longer considered to be Hawaiian endemics.

Leviathan cowries are heavy shells; they definitely are not fragile. And like almost all cowries, they have a wonderful china-like look to them.

Cypraea leviathan
One of the distinctive features of the shells of Leviathan cowries is a row of violet teeth bordering each side of the aperture on the underside of the shell. You can see those unusual violet teeth clearly in the second photo on this page. There are several other cowries in Hawaii that have marking similar to the Leviathan, but they are smaller -- and they do not have those wonderful violet teeth!

Another distinctive feature of Leviathan cowries has nothing to do with the shell, but rather with the snail that secretes and inhabits the shell. Readers may recall the photos of a live Tiger cowrie that we posted here on The Right Blue earlier this year. When the creature's mantle was extended over the shell, you could see that it had rubbery-looking thingies sticking out all over it. Those are called papillae. Well, the papillae of Leviathan cowries are quite different. They are spiky clumps that look like little bushes!

The papillae on the mantle of the Leviathan are difficult to describe, and I don't have a photo of a live one to post. Fortunately there is a video on YouTube that shows a live Leviathan with its mantle extended over the shell. You can see the weirdly shaped papillae on the mantle.

Here is makuabob's video, Meet Cypraea leviathan:

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

All set for a pajama party on the reef?

by B. N. Sullivan

The common name for this little creature is Striped Pajama Nudibranch. Its scientific name is Chromodoris quadricolor. These nudies are small -- less than two inches (5 cm) in length -- but their bright colors make them easy to spot.

This species is very common in the Red Sea. In fact it is probably safe to say that this is the nudibranch seen most frequently by Red Sea divers. C. quadricolor also is found elsewhere in the Indo-Pacific region. They are sponge eaters.

Those two orange structures sticking up from the forward end of the creature are its rhinophores - sensory organs that help it navigate and find food. The rhinophores sense chemical molecules in the water similarly to how we sense smells in the air.

The bunch of feathery-looking things protruding from the tail end of the nudibranch are its gills, used for respiration. The gills can be retracted into a tiny pouch on the nudibranch's back. If you see one of these guys and it appears to have no gills, look for a little bump where the gills should be. That's where they are hidden.

Like many of its colorful cousins of the same genus, the Striped Pajama Nudibranch is a favorite photo subject for underwater macro photographers. No surprise there: it is colorful, photogenic -- and like most snails, it doesn't move very quickly. (Photographers are particularly fond of brightly colored critters that will hold still long enough to focus the lens!)

I photographed the individual on this page in the Red Sea at a place called Shark Bay, which is not far from Sharm el Sheikh, Egypt. [Click on the photo to enlarge.]

Whale sharks, mantas, stingrays, barracuda, jacks...

What else can you identify in this wonderful video shot at the Okinawa Churaumi Aquarium in Japan?

Said to be the second largest aquarium tank in the world*, Jon Rawlinson, the videographer, explains:
The main tank called the 'Kuroshio Sea' holds 7,500-cubic meters (1,981,290 gallons) of water and features the world's second largest acrylic glass panel, measuring 8.2 meters by 22.5 meters with a thickness of 60 centimeters. Whale sharks and manta rays are kept amongst many other fish species in the main tank.
Visit Jon Rawlinson's website to see more of his work.

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

* The Georgia Aquarium in Atlanta is billed as the world's largest aquarium - more than 8 million gallons.

Regional color variation in a marine crab species

by B. N. Sullivan

Carpilius convexusLast month we talked about some fishes that have color phases that change with developmental stage. We pointed out that these variations sometimes make it difficult to identify a species by color alone.

The same can be said for some kinds of marine invertebrates. In fact, some invertebrate species also vary in color from one location to another.

The crabs pictured on this page resemble each other in shape and size. Each is red with a carapace about three inches (8 cm) across. The shape of their bodies, appendages and claws are virtually identical; so is the spacing and positioning of the retractable eyestalks.

You could guess straightaway that they belonged to the same family (Xanthidae). Their similarity also might prompt you to surmise that they belonged to the same genus; but if you hesitated to identify the two as the same species, you would be forgiven. Although they both are red, the first crab has a much richer color, and a more striking pattern of spots on its carapace and legs, while the second crab is considerably paler, and is mottled with light grayish spots that look quite different than the darker spots on the first crab.

I photographed the first crab years ago in the Red Sea. By poring through published reference books, I was able to identify the species as Carpilius convexus.

Carpilius convexusMuch later, and thousands of miles away, I photographed the second crab in the Pacific Ocean off the coast of Hawaii. When we first looked at the photo, we commented that it resembled Carpilius convexus from the Red Sea, so we assumed it must be a relative. What we did not realize at first was that the second, lighter colored crab was indeed a member of the same species.

It turns out that the coloration of each of these crabs is typical of the species in each location. If you look at reference photos from the Red Sea, you will see pictures of the darker red version with the well-defined spots. If you look at reference photos from Hawaii, you will see the paler colored crab with the grayish mottling.

These color variations are quite consistent within the populations at each location, but what we don't know is why the species developed these external differences. If you believe, as we do, that these kinds of characteristics evolve over time and become prevalent for reasons that relate to survival, then you have to wonder what those reasons might be.

Could it be that the richer coloration of the Red Sea variant somehow reflects its colorful environment? In the Red Sea, this crab species lives among very colorful Nephtheid soft corals, so perhaps its brighter coloration helps it to 'blend' better with its surroundings.

Conversely, the paler color variant may be more suited to living -- and hiding -- among the drabber hard corals that predominate on Hawaii's reefs. Here in Hawaii we have no brightly colored soft corals like the Nephtheids in the Red Sea.

This is conjecture on our part, of course. There may be other explanations for the regional color variation: diet perhaps? Maybe one day we will know the answer.

About the photos: Both photos show adult crabs of the same species, Carpilius convexus. The photo at the top of the page was taken in the Red Sea at Ras Um Sid, near Sharm el Sheikh, Egypt. And yes, the poor critter has lost one cheliped (arm). The second photo was taken in the Pacific Ocean off the coast of Hawaii's Big Island, near Puako.

Lunartail Grouper (Variola louti)

What: Lunartail Grouper (Variola louti). Length: about 38 cm (15 in).
Also called Lyretail Grouper, both common names refer to the pale crescent on the tail fin.

Where: I took this photo in the Red Sea, off the coast of the Sinai Peninsula.
This species also lives in the Indian Ocean.

Variola louti
Click on the photo to enlarge.

Fire Coral Redux

Our readers ask us a lot of questions about diving, about locations we have visited, and about marine life. Fire Coral is among the topics asked about most frequently. People want to know where it is, what it looks like, and what to do if they are stung by Fire Coral.

Back in late 2007, we posted two articles about Fire Coral, along with some photos of examples of the kinds of Fire Corals most commonly encountered by divers and snorkelers in the Caribbean Sea and the Red Sea. Although those articles receive a lot of traffic from search engines, we decided to post the links to both for the benefit of our newer readers who might not have known about them.

Fire Coral: Look, but do not touch gives an overview of Fire Coral, and how its nematocysts work to sting whoever brushes up against them. The article includes a photo of Millepora alcicornis, a Caribbean species of Fire Coral, and a macro photo that shows the dactylozooids, the tiny hair-like structures that contain the Fire Coral's stinging nematocysts.

Fire coral: Another view displays a wide-angle image of Millepora dichotoma, the Fire Coral species encountered most frequently in the Red Sea.

For those of you who prefer to listen rather than read, here is a video about Fire Coral, produced and narrated by Don Stark of ScubaVisions.com.

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

Ghost Shrimp (Stenopus pyrsonotus)

What: Ghost Shrimp (Stenopus pyrsonotus)
Also called Flameback Coral Shrimp.

Where: I took this photo at Puako, Hawaii.

Stenopus pyrsonotus
Click in the photo to enlarge.

You can't always identify a fish by its color

by B. N. Sullivan

You know that old cliché: You can't judge a book by its cover. In a sense, the same can be said for many fish species. Countless species exhibit different colors and patterns as they develop. In fact, sometimes juveniles and sub-adults look markedly different from the adults of their kind.

This is confusing to divers trying to learn the names of the fishies they see underwater, and in some cases it even has tricked scientists. Taxonomic records of fish species have many, many examples of fishes that were thought at first to be two distinct species, but later turned out to be different color phases of the same species.

Cantherhines macrocerosThe two individuals in the photo at right are an example of this phenomenon. They are both Whitespotted Filefish (Cantherhines macroceros), a Caribbean species common on reefs around Belize and the Cayman Islands. They appear in two distinct color phases: one with spots, and one without.

Of course, this happens on land, too. Just think of Bambi, for instance. As a fawn, Bambi had spots on his back -- spots he outgrew as he matured into an adult deer.

The fishes in the photo at least resemble one another, but some fish species undergo really radical color changes as they mature. Not only that, many reef fishes even change sex! Some species begin life as females, and later turn into males, a condition called protogyny. Then there are the protandrous species, which begin life as males and ultimately become females. There are even a few species that can change sex in both directions. Talk about gender-bending!

Like a lot of land animals, many fish species are sexually dimorphic, that is, the two sexes differ in appearance. The males are usually (but not always) the ones that are larger and more brightly colored. I've always thought that sexual dimorphism made obvious sense; if the two sexes look different, than each should be more readily able to spot a potential mate.

It turns out, though, that mate attraction is a much more complex process, probably less dependent on visual cues like color and size, than on subtle biochemical sensing (i.e., scent, or the fishy equivalent thereof). In any case, when critters -- including fishes -- need to find a mate, they know what to look for.

And that reminds me of a conversation we had one time with ichthyologist Jack Randall of the Bishop Museum in Honolulu. We described to him a peculiar individual fish we saw regularly at a certain patch of the reef at Puako. The fish was a Yellow Tang (Zebrasoma flavescens) with an odd color pattern. Usually that species is solid yellow, but this individual had irregular white blotches on it, such that it looked like it had been splashed with bleach! Dr. Randall told us that similarly patterned Yellow Tangs had been noted occasionally, and that it was presumed to occur because of some mutation to the genes that control pigmentation.

Another diver who was present said he had seen a Yellow Tang with similar white blotches several miles south of where we regularly saw 'our' little mutant. We mused aloud about what might result if we could get those two fishies with the aberrant color patterns to mate. Maybe we could capture one and release it near the other in the hope that they would produce some interesting offspring.

But then Jerry asked, "What if both are males or both are females?" Both sexes of Yellow Tangs look exactly alike. There's no way to tell them apart visually.

Jack Randall just grinned and winked. "Don't worry," he said. "They know."

Nassau Grouper: Overfished and Now Endangered

What: Nassau Grouper (Epinephelus striatus). Valued as a food fish,
but over-harvested -- now classified as Endangered by the World Conservation Union (IUCN).

Where: I took this photo during a night dive off the coast of West Caicos, Turks & Caicos Islands.
Nassau Groupers are found throughout the tropical West Atlantic and Caribbean.

Click here to learn more about the Nassau Grouper.

Nassau Grouper (Epinephelus striatus)
Click in the photo to enlarge.

Wordless Wednesday
Watery Wednesday

Another Dimension of The Right Blue

TwitterVisitors to The Right Blue may have noticed that we added a Twitter button to our sidebar awhile back. On the other hand, those who read The Right Blue via the RSS feed would not have known about that Twitter button. So, we decided it might be a good idea to post a quick announcement about our Twitter feed: @therightblue

Jerry is the primary Twitterer for The Right Blue. He tweets the title and link to each new post on the blog, of course, but that is just a small fraction of what we view as a new dimension for The Right Blue.

As @therightblue, Jerry tweets news and other information about all things ocean: scuba diving, underwater photography, maritime archaeology, ocean conservation and ecology, developments in oceanography and marine biology -- and whatever else strikes his fancy on a given day! He also passes along information about upcoming events related to all those topics via re-tweets.

Of course it's not all titles and links. Jerry adds his own brief comments, and the Twitter feed is liberally sprinkled with Jerry-style one-liners and dialog with fellow Tweeps.

If you're on Twitter, and you want to stay current with all things ocean, we invite you to follow @therightblue. Click on the button near the top of the side bar on the blog, or on the big fat Twitter button on this post.

One more thing: If you're not on Twitter, Jerry says he's got some eight-track tapes he'd like to sell you. ;-)