Please do this one small thing for marine research

You visit The Right Blue because you like the ocean, and you like to see learn about the creatures that live in the sea, right? We'd like to ask you, our readers, to do one small thing that can aid marine research. It won't cost you any money -- just a minute of your time, and lending your name to a very good cause.

We'd like you to click here to sign an online petition. Here's what it's about:

The Johnson-Sea-Link I & II submersibles and their support ship, the research vessel R/V Seward Johnson, may be taken out of service. Kevin Zelnio over at Deep Sea News explains:

A shining legacy of deep sea research is under threat from the state of Florida. Citing economic problems and the high cost of maintaining equipment and crew, the Harbor Branch Oceanographic Institution (HBOI) has announced it’s intention to sell or retire the submersibles and its mother ship the R/V Seward Johnson II. Concerned citizens from the state of Florida have created a petition and are asking for people to “invest in science, education and technology.”

So very little of the ocean depths have been explored. Research submersibles like these afford marine scientists opportunities to view undersea environments, observe deep-dwelling marine life, and collect samples for further study -- activities that cannot be accomplished by any other means.

These submersibles are not tourist rides; they are essential research tools. Please help to insure that they will continue to be made available to the scientists who need them. Click here to sign the online petition. Do it as a favor to The Right Blue.

Here are a couple of videos from the Johnson Sea Link submersibles:



Click here to watch the above video on YouTube.



Click here to watch the above video on YouTube.

Whitemouth Moray Eel (Gymnothorax meleagris)

What: Whitemouth Moray Eel (Gymnothorax meleagris).
They grow to about 1 meter in length, but this individual was about half that size.

Where: I took this photo while diving at Puako, Hawaii.
This species is common throughout the Indo-Pacific region.

Click in the photo to enlarge.

Hawaiian Green Sea Turtles

by B. N. Sullivan

In recognition of World Turtle Day, May 23, we have decided to tell our readers a few things about our favorite turtle species, the Hawaiian Green Sea Turtle (Chelonia mydas), known as Honu in the Hawaiian language.

Our Hawaiian Green Sea Turtle population was nearing extinction not too long ago, but thanks to Federal and State protection laws and sound conservation efforts, the Honu population is slowly beginning to recover. These days these turtles are a common sight around many of the reefs and shorelines of the main Hawaiian Islands.

Hawaii's Green Sea Turtles nest in the uninhabited Northwestern Hawaiian Islands, primarily in the area called French Frigate Shoals. Tagging studies have shown that sea turtles tend to nest once every two to five years on the same beaches where they were hatched. When they are finished mating and nesting, they migrate hundreds of miles back to the main islands, which are their foraging grounds.

More recently it also was discovered, through tagging and telemetric monitoring, that individual Green Sea Turtles tend to 'hang out' in the same foraging area for periods of years. Once they find their spot, they don't wander very far, except when the time comes to migrate again to the nesting grounds. We have anecdotal evidence of this as well. Over our years of frequent diving and beachgoing at the same places, we learned to recognize a number of individual sea turtles. We saw those individuals again and again and again within a very small range for years at a time.

Long-time readers of The Right Blue may recall our stories about a particular turtle we named Myrtle. This individual lived for years in a certain small cove along the shoreline at Puako, on the Kohala Coast of Hawaii's Big Island.

Quite a few turtles reside in that area, but we began to recognize this one particular turtle because she had a small but noticeable blemish right in the center of her carapace. That little blemish in her shell set her apart from the others and made her easy to spot.

Once we learned to recognize Myrtle, we noticed that she could be found at almost any time in the same little cove. Most often we would see her grazing on the limu (seaweed) that covered the rocks in the shallow water of that cove. In fact, she seemed to spend most of her time feeding. That's Myrtle in the second photo, foraging for limu, along with a much smaller companion (called Baby, naturally).

Occasionally we would see Myrtle out on the reef while we were diving, but there was nothing random about where we would see her: Myrtle had a favorite spot near the base of one particular coral formation. We saw her repeatedly in that exact place, being cleaned by surgeonfish, or just resting.

Myrtle also engaged in basking, a behavior peculiar to Hawaii's Green Sea Turtles. In most places around the world, sea turtles only leave the ocean and come up onto the shoreline to nest. Here in Hawaii, there are a number of locations where Honu haul themselves completely out of the water and bask in the sunlight. No one is exactly sure why Hawaiian Green Sea Turtles engage in this basking behavior. It may have something to do with temperature regulation and metabolism, or it may be a way to rest without fear of being preyed upon.

(Or could it be that, just like the thousands of tourists who spend time basking on Hawaii's beaches, the turtles are just 'working on their tans'??)

Regardless of the reason, it is not uncommon to see a number of sea turtles basking along certain shorelines any day of the week. Puako is one of those areas. The sight of sea turtles lying motionless on the rocks or sand surprises people who have never before witnessed this behavior.

As I wrote in an earlier article about Puako's tidepools and turtles:

Many newcomers and tourists become alarmed when they first spot the turtles on the beach or the rocks at Puako. They assume that the turtles somehow got stuck there as the tide receded, or that they might be injured. Sometimes it takes quite a bit of explaining to convince them that this is the natural behavior of these creatures. The basking turtles are not in distress, and they need no assistance to get back into the ocean. (Honest!)

We love our sea turtles, and we love to show them to visitors. There are some rules that must be followed, however.

Never disturb a sea turtle that is basking on the shoreline, grazing in the shallows, or resting on the reef. Don't try to touch or pet them. Don't try to feed them. And if you encounter a sea turtle while you are swimming, snorkeling or diving, PLEASE do not try to ride it!

Sea turtles are air breathing animals. They can remain underwater for a considerable amount of time, but sooner or later they have to come to the surface for air. Nothing frightens a sea turtle more than being restrained underwater. They know instinctively that this means they cannot surface to breathe. Please don't terrorize our turtles by doing anything that they might interpret as restraint.

The Honu -- Green Sea Turtle -- is the most common species of sea turtle in Hawaiian waters. Two other sea turtle species are seen here less frequently. Hawksbills (Eretmochelys imbricata) -- called Honu'ea in Hawaiian -- do visit our reefs and shorelines, but in much smaller numbers than the Honu. Leatherback sea turtles (Dermochelys coriacea) are found in our neighborhood as well, but only in the open ocean, well offshore.

The Honu photos on this page were taken at Puako, Hawaii. You can click on them for a larger view. Click here for an index to all of the sea turtle articles and photos on The Right Blue.

If you would like to learn more about Sea Turtles, we recommend the Turtle Trax website, and the Sea Turtle Restoration Project website.

UPDATE June 8, 2009: We are pleased to announce that this article was included in the 25th Carnival of the Blue, a monthly compilation of the best of ocean blogging.

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Note: Some of the information in this article was derived from the following sources:

Balazs, G.H. (1995). Status of sea turtles in the central Pacific Ocean. In K.A. Bjorndal (Ed.), Biology and conservation of sea turtles (pp. 243-252). Washington, DC: Smithsonian Institution Press.

Balazs, G.H., Rice, M., Murakawa, S.K.K., & Watson, G. (1996, June). Growth rates and residency of immature green turtles at Kiholo Bay, Hawaii. Proceedings of the Sixteenth Annual Symposium on Sea Turtle Biology and Conservation, Hilton Head, SC.

Whittow, G.C., & Balazs, G.H. (1982). Basking behavior of the Hawaiian green turtle. Pacific Science, 36(2), 129-139

The Armored Division: A Ridgeback Slipper Lobster from Hawaii

What: Ridgeback Slipper Lobster (Scyllarides haanii); length about 20 in (50 cm).
They're edible, but taking them in Hawaii is limited to a state-regulated season.

Where: I took these photos during a night dive at Paniau Cove, Puako, Hawaii.

Click on the photos to enlarge.

Tiger Cowries: The largest cowries in Hawaii

by B. N. Sullivan

Tiger Cowries (Cypraea tigris) have several claims to fame in Hawaii. Two of those claims have to do with their size. The third claim to fame has to do with a traditional use for the shell. (More on that in a bit.)

Tiger Cowries live on tropical reefs in a wide range of places throughout the Indo-Pacific region. They can be found as far west as the Red Sea and the Indian Ocean, and as far south as the tropical shores of Australia. They live as well along the coasts and islands of southeast Asia, and in many locations in the tropical western Pacific. Hawaii is the northeastern-most place on the globe where Tiger Cowries are found.

Tiger Cowries are the largest of the many species of cowries found in Hawaii. Not only that, those in Hawaii grow larger than Tiger Cowries found anywhere else in the world. In Hawaii, Tiger Cowries can grow to nearly 15 cm (about 6 in). Elsewhere, they rarely grow bigger than 10 cm (about 4 in).

Hawaiian Tiger Cowries occur in reef areas at depths from about 4 m to 40 m (about 10 ft to 130 ft). This depth range is another thing that sets them apart from Tiger Cowries found elsewhere. Outside of Hawaii, the species usually is found only in shallow waters, including the inter-tidal zone.

Snorkelers and divers sometimes get to see these shells during the day. Tiger Cowrie shells are very beautiful: they are white or creamy ivory, and covered with irregular dark spots. The spots are mostly brown, but some individuals have a mixture of brown and bluish gray spots. The elaborate pattern of spots on each shell is unique.

The snails usually stay tucked up inside their shells during the day and forage at night, so you have to find one after dark to see evidence of the gray snail that lives inside. At night the animal emerges and crawls along the reef, carrying its shell on its back.

The first photo on this page is a head-on shot of a Tiger Cowrie snail poking out of its shell. If you look closely, you can make out the snail's proboscis and tentacles. It uses these organs to 'sniff' for food and gather it into to its mouth. Tiger Cowrie snails are herbivores -- that is, they eat seaweed and algae.

As the snail moves along to graze at night, it extends its mantle up over the shell. The mantle, with its prickly looking papillae, acts like camouflage when it covers the shell. The snail secretes a mucus that not only facilitates sliding the mantle over the shell, it also keeps the surface of the shell polished and shiny, looking like glazed china or porcelain.

In the second photo on this page, the snail is just beginning to slide its mantle up the side of the shell. In the third photo, the mantle has extended almost completely.

Now, about that third claim to fame. Tiger Cowrie snails are a favorite food of octopus. This was a fact well-known to traditional Hawaiian fishermen, who made lures from Tiger Cowrie shells to attract 'tako' (as octopus is called here in the islands).

Some Hawaii fishermen still use these lures to fish for tako. Writer Jim Rizzuto, well-known in Hawaii for his books and newspaper columns about fishing, discusses these lures and explains how they are made in his book Fishing Hawaii Style, Volume 2 (Honolulu: Hawaii Fishing News, 1987). He notes that the local Tiger Cowrie shell "is easy for the tako to see and is irresistible."

If you would like to try your hand at making a traditional tako lure from a Tiger Cowrie shell, here is a a link to a document from the University of Hawaii at Hilo that tells how to do it: Create a Hawaiian Tako Lure (11-page 'pdf' file).

About the photos: All of the photos on this page are of the same individual. I took these photos during a night dive at Paniau, at the southern end of Puako reef, which is on the western coast of Hawaii's Big Island. Click on any of the photos for a larger view.

Big News: The Right Blue Joins FBI Bloggers (no, really!)

Earlier this week we were invited to join FBI Bloggers, and we gladly agreed to become a part of the team. No, not that government organization. FBI in this case stands for 'From Big Island' -- that is, the Big Island of Hawaii, our home.

FBI: From Big Island. That's us!

Awhile back, Big Island blogger Damon Tucker decided to create a website to gather "the Big Island's best blogs" into one location. FBI Blogs is that website.

What a great idea: all of the Big Island's top blogs in one place -- a microcosm of great blog content (and ad-free). As Damon says, "The FBI site is not designed to make money or do anything except to showcase our blogs from the Big Island."

We're very proud and honored that The Right Blue is part of this very special, very talented blogging community. We invite all of our readers to visit FBI Blogs and enjoy the wonderful and diverse content produced by the writers and photographers who are FBI bloggers. If you like what you see, bookmark the site, or subscribe to the RSS feed.

Sea Turtle says: You go that way, I'll go this way.

What: Green Sea Turtle (Chelonia mydas) on a Malaysian reef.
She decided to head in the opposite direction from the divers in the background!

Where: I took this photo while diving at Pulau Sipadan,
off the coast of the Malaysian side of Borneo.

Click on the photo to enlarge.

The Right Blue: Nominated for a Blogger's Choice Award

A regular reader of The Right Blue, Jenn Thorson, has nominated us for a 2009 Blogger's Choice Award. The nomination came as a complete surprise to us, and we are very honored that Jenn thought enough of The Right Blue and Bobbie's underwater photography to nominate our blog in the Best Photography Blog category.

We have never before been nominated for a competitive award, and to be honest, we're not quite sure how it all works. But, we'll put the clickable badge on our sidebar and see what happens! If you do like The Right Blue -- and especially the photography -- we hope you will vote for us.

We already have thanked Jenn Thorson privately for the nomination, but now we'd like to say it publicly as well: Thank you, Jenn. You couldn't have given us a better surprise. We are very touched.

Stingrays: Dangerous or Not?

by B. N. Sullivan

Our previous pictorial post about a dive site in the Cayman Islands called Stingray City generated a lot of interest, and quite a few questions about stingrays. We decided to tell our readers some more about these interesting marine animals.

Stingrays are found in warmer waters around the world. Stingrays are Elasmobranchs - a classification of fishes that include sharks and other kinds of rays, like Mantas and Eagle Rays. Elasmobranchs differ from other fishes in that their skeletons are made of cartilage rather than bone.

There are many species of stingray. The species pictured on this page, and in our photo essay about Stingray City, is the Southern Stingray (Dasyatis americana). It can be found in the warmer latitudes of the Western Atlantic, and throughout the Caribbean and the Gulf of Mexico. They are found most often in relatively shallow waters where there are sandy bottoms, because that is where they find their food.

The diet of these creatures consists of small animals that live in the sand - mostly shellfish, small crustaceans and worms. The stingray feeds by hovering directly over the sand and fluttering the wing-like edges of its body disc to clear away the top level of sand. This exposes the little creatures that live just under the sand, and the stingray plops on top of them and eats them.

The photos in an earlier post on The Right Blue shows a Southern Stingray hunting for its dinner on a sand flat in the Turks and Caicos Islands.

The stingray's mouth and gill slits are on the underside of the body. You can see the mouth and gill slits clearly in the second photo of our post about Stingray City. The stingray's eyes are on the top of its body, as you can see in the photos on this page. When stingrays lie on the sand, they flutter their 'wings' a bit to cover themselves with sand until only their eyes and the end of their tail are visible.

But what about the 'stinger' that gives the stingray its common name?

The 'stinger' actually is a barbed spine that is located at the base of the stingray's tail. The barb contains a venom and is the stingray's defensive weapon. It does not use the barb on prey.

Stingrays spend a lot of time swimming just over the surface of sandy bottoms, looking for food. When they feed, and sometimes when they rest, they settle onto the bottom and lie flat. Thus, whether resting or hunting, they are subject to predation from above. If they are disturbed from above while they are on the sand, they quickly erect the barbed spine at the base of their tail as a defense.

The stingray's tail does not have a 'stinger' at the end of it, and they do not sting divers or prey by whipping their tails around. Most people who have had nasty encounters with stingrays have been divers and waders who accidentally stepped on a ray, or swam closely over one that was half-buried in the sand.

Many people will recall that Steve Irwin, the well-known Australian environmentalist and television personality, met his death after an unfortunate encounter with a stingray in 2006. Ironically, Steve was filming an underwater documentary about the ocean's deadliest creatures at the time of the incident.

Apparently Steve Irwin either laid down on top of a stingray, or swam just a few inches above where one was buried in the sand. The stingray did what stingrays do when some creature threatens them from above: it quickly raised the barbed spine at the base of its tail. Unfortunately, the barb pierced Steve Irwin's chest.

Irwin's death was sobering to divers and especially to underwater photographers. I think it is safe to say that every underwater photographer or videographer in the world has spent a considerable amount of time lying or kneeling on the sand to take pictures. Steve Irwin's death was a dramatic reminder to look carefully at the surface of the sand for evidence of a partially buried stingray before settling there.

So, are stingrays dangerous? In certain circumstances, yes; in most cases, no.

Here are some earlier posts on The Right Blue that feature stories and photos of stingrays:

• Stingray City, Grand Cayman Island - photos of a Southern Stingrays interacting with divers
• Picture this! - photos of a Southern Stingray hunting with a Bar Jack (Caranx ruber)
• The 'eyes' have it - features close-up images of a Blue-spotted Stingray (Taeniura lymma)
• Blue Spotted Stingray at Pulau Sipadan - photo only
• On a collision course with critters in the sea - story and photo of a large deep-dwelling stingray species in Hawaii (at the bottom of the page)

Stingray City, Grand Cayman Island

What: Divers interacting with Southern Stingrays (Dasyatis americana).

Where: I took these photos while diving at Stingray City,
a well known dive site in the Cayman Islands.

[Click on the photos to enlarge.]

Diving Is Not for Everyone

by B. N. Sullivan

We are contacted rather frequently by readers who want to know if we are diving instructors. After reading The Right Blue, they say, they want to learn how to dive, and they would like to learn from us.

We are always touched and flattered by those kinds of messages, but we have to say that no, we are not dive instructors. Both of us are trained and certified as divemasters, but we don't work as divemasters or dive guides either. As we explained in a much earlier post, we became certified as divemasters out of self-interest -- so that we would be qualified to manage our own dives, both at home and when we travel.

Nevertheless, we have coached many new divers to help them develop their skills, and we have advised many others on issues pertaining to diver training, equipment choice, and the like. We are happy to share what we know -- we just do it in an informal manner.

Quite recently, we have had a flurry of inquiries from people who are just beginning their first diving course, or who are thinking of doing so in the near future. Several have expressed a combination of enthusiasm and reservation: They want to learn to dive, but at the same time, they are more than a bit scared.

We have responded individually to those inquiries, but we thought it might be a good idea to share publicly some of what we said, for the benefit of other prospective divers who were too shy to ask us directly. This will be the first in a series of articles about learning to dive.

If you love being in and around the water, you're in reasonably good physical shape, you love to swim and are comfortable in lakes or the sea, and you want to learn to dive, go for it! Seek out a reputable instruction program that offers a widely recognized certification, and dive right in.

But what if you're not such a good swimmer? What if most of your swimming has taken place in pools and you're worried about diving in open water? Should you sign up for a scuba course and hope for the best?

Every dive instructor can recount stories of people who showed up for their first dive class, barely able to doggie paddle across the width of a backyard pool. What were they thinking? One total non-swimmer who showed up for a class run by an instructor friend of ours said she figured it didn't matter that she didn't know how to swim on the surface. She believed that having an air supply would make up for the fact that she didn't even know how to float! The instructor gently pointed out that eventually she would at least need to swim to and from the beach or dive boat, so if she couldn't do that, she would not be able to proceed with the dive course.

If you are not a reasonably good swimmer, or if you are not confident of your skills in the water, it might be a good idea to work on improving your swimming skills before you begin diving instruction. You don't have to be a champion swimmer, you don't need to be able to swim fast, and you don't need to have perfect form, but you should have mastered basic competencies like being able to tread water for several minutes, swim several lengths of a pool un-aided, and so on.

If most of your swimming has been in pools, and rarely in natural bodies of water - lakes, rivers, sea -- then you may feel anxious when you first venture into open water. There's something about all that open space -- the lack of visible walls and a nice flat, clean pool bottom -- that unnerves some people the first time they go swimming in the ocean or a large lake.

Lots of pool swimmers have good basic skills, but they have to learn what to do about things like surface chop, swells, waves and currents. They often have initial fears about all those creatures in the open water, too. If you have been mostly a pool swimmer, we advise that you spend some time snorkeling in natural bodies of water before you begin scuba lessons, just to become more comfortable with the conditions and surroundings.

Some people sign up for scuba instruction solely because they are urged to do so by someone else. Their spouse or significant other (or parent, child, cousin, friend) either is a diver, or is learning to dive, and wants a companion. We would be the first to tell you that having a regular dive partner that you know well away from diving is a wonderful thing. But if you are going to take dive lessons only because someone else has urged you to do so, it may be a mistake -- especially if some of the factors above, relating to swimming skills and comfort in the water, also apply.

Lots of couples and pairs or groups of friends learn to dive together. Some become lifelong dive companions. However, if you are otherwise uninterested in diving, or you are uncomfortable in the water, but you are being nudged to go through a course to satisfy someone else, you might want to reconsider.

Again, the key factor is comfort. If you are not at ease while swimming in the ocean or a lake, if you are not confident of your swimming skills, diving may not be right for you at this time. Once you spend more time in the water, and once you improve your skills so that you feel relaxed, then you can think about learning to dive.

We hope the title of this article does not put off would-be divers. We like to promote sport diving for people who really want to do it, but some people are just not well suited to be divers. We think it's better to take a realistic look at your own suitability -- your skills and limitations -- ahead of time.

If your skills or comfort level in the water are less than optimal but you really want to dive, you can and should prepare to do it. If you are planning to learn to dive only because someone else wants you to do it, think again. Diving is not for everyone.