Earth Day Greetings from the Blue Marble

by B. N. Sullivan

Behold, our favorite image of  Earth --  the 'Blue Marble'.  This now-famous photograph was taken on December 7, 1972 by the astronauts of Apollo 17, which was the last manned mission to the moon.  The photograph, listed in the Apollo 17 Image Library as AS17-148-22727, is described this way:

A Full Earth from the Apollo 17 Command Module at about 5 hours 6 minutes, shortly after separation of the docked CSM-LM from the S-IVB at 4 hours 45 minutes. Note that the trajectory is far enough south that Antarctica is visible.

That simple description belies the stunning impact of this iconic image.  If anything can remind us of the interconnectedness -- the oneness -- of the Earth's seas, land masses, and atmosphere, the evocative imagery of the Blue Marble  is it!

This Earth Day, regardless of what else you do, we encourage each of you to pause and reflect on the Blue Marble. That's our home --  the only one we'll ever know.  Each of us individually, and all of us together, must do whatever we can to look after it.

Video: Underwater junkyard off the California coast

by B. N. Sullivan

We've posted several articles about a nasty ocean environmental issue: marine debris.  Since this is one of our pet peeves, we have repeatedly reminded divers and beachgoers to deposit their trash in proper receptacles or to take it home with them.  Moreover, we have asked them to pick up and properly dispose of debris they find on the beach and in the water, including abandoned nets and fishing tackle, even if they did not put it there to begin with.

Being mindful about trash such as picnic remains and general litter can help to reduce damage to reefs, the pollution of waterways, and the risk of entanglement by marine wildlife -- and that's a good thing. But a much more serious and pervasive problem exists as well: using the ocean as a dump!

Have a look at this Fox News video, and you'll see what we mean:

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

Thanks to @scubadivergirls and Deep Sea News for alerting us about this video.

Don't feed the critters

by B. N. Sullivan

There are some dive sites where you know immediately that the fishes and other critters are used to being fed by divers and snorkelers.  How can you tell?  You can hold out your hand, like Jerry is doing in the photo above, and see if the fishes come forward.  Sometimes you don't even need to extend your hand.  At some sites, the fishes begin to converge on divers as soon as they descend from a boat.

So, is feeding the critters a bad thing or an okay thing to do?  Generally speaking, we advise against it.

For one thing, it can be disruptive to the critters in a number of ways.  Feeding an animal something that it would not naturally eat can disrupt its digestion and nutritional status.  Even if you choose to feed something the animal might normally eat, you alter its natural feeding behavior by supplying the food item.

For another thing, feeding critters encourages them to congregate in places where they might not normally stay -- like at the base of a boat mooring.  While the critters may learn that if they hang out in a particular place, they will be fed, their predators also learn this.  You may be setting up the unsuspecting recipient of your offerings for becoming a meal himself!

And then there's the diver safety issue.  If you've ever been mobbed by a swarm of fishes expecting a handout, you know what I mean. We have been followed around on many occasions by fishes that had become accustomed to being fed -- including eels and stingrays.  As annoying as being mobbed by Snappers or Butterflyfishes may be, it can be worse -- even dangerous -- if the hungry critters are large and/or toothsome and aggressively pursue divers expecting a treat.

Long-time readers of The Right Blue may recall a story we told awhile back about a particularly aggressive Napoleon Wrasse in the Red Sea.  The huge fish was accustomed to being fed boiled eggs.  The wrasse  apparently mistook the white second stage of our friend's regulator for an egg, and chomped it hard enough to detach it from the hose.

We know a dive guide who used to feed a certain large Moray eel, and then pet it.  One day he reached out to pet the eel and it snapped at him, clamping down on his finger.  At the hospital emergency room the doc said the only reason the dive guide did not lose that finger was because he was wearing a heavy class ring, which probably deflected the eel bite just enough to save the digit (although it was pretty badly mangled).

Remember, folks.  The creatures you see in the ocean are wild animals, not pets.  Don't give them indigestion and don't mess with the natural food chain.  Don't feed them.

About the photo:  I took this photo of Jerry (and a handful of Yellowtail Snappers) at the wreck of the Oro Verde, located off Grand Cayman's Seven Mile Beach.

So, there was this tsunami in Hawaii...

by B. N. Sullivan

Here in Hawaii, the drama began on Friday evening, Feb. 26, 2010, while I was watching the Olympics on television.  As is usually the case when I watch TV in the evening, my mini netbook was on my lap, and I was playing a game on it.  In addition to the game, I had Twitter open in my browser -- not wanting to miss anything that might be happening somewhere in the world.  (I admit it: I'm a breaking news junkie!)

At exactly 8:36 PM Hawaii time, I saw the first mention on Twitter of a huge earthquake off the coast of Chile.  The first report said the magnitude was estimated to be 8.3.  A few minutes later, that estimate was changed to 8.5, and a tsunami warning was issued for Chile and Peru.  Roughly an hour after that, the magnitude of the quake was upped to 8.8, and it was announced that a tsunami had indeed been generated.

That was it for me.  I had no further interest in my game, the Olympics, or anything else on TV, save for the news.  I watched the story develop on TV and on the Web until about 3 AM, when I could stay awake no longer.  But by that time I knew that a tsunami was headed across the Pacific; that an official tsunami warning had been issued for Hawaii; that coastal evacuations would begin at 6 AM; and that the tsunami was projected to reach Hilo minutes after 11AM on Feb. 27.  Believing (correctly, it turned out) that most of my family members and friends on the Big Island already were asleep when the tsunami warning was initiated, I sent tweets and emails to them to give them a heads up about what we all would face when morning came.

Promptly at 6 AM -- right on schedule -- the civil defense sirens along the coast began to wail their warning to those who lived in inundation zones to prepare to evacuate.  The sirens warbled again, each hour on the hour, until 10 AM when roads along the coast, as well as those that led into and out of the inundation zones were closed.  Coastal evacuees traveled inland and upslope; vessels left the harbors and went far out to sea to wait in open water; some small craft were trailered inland for the duration.

We sat tight at our house, not needing to evacuate since we live on a hill at an elevation about 500 feet above sea level.  At 10:30 AM the final warning siren sounded.  I have to admit, it was a bit nerve-wracking.

We watched live coverage of the scene at Hilo Bay.  Everyone was nervous.  After all, the epicenter of the  present quake was very near that of another great quake in 1960, which generated a tsunami that wiped out much of downtown Hilo and claimed 61 lives.  In addition, people of our era have seen vivid images of the Boxing Day Tsunami that followed a huge earthquake off the coast of Sumatra on Dec. 26, 2004, which swept  across the Indian Ocean, killing hundreds of thousands of people.  All of this was on our minds, but no one knew exactly what to expect.

The predicted time of arrival for the tsunami came and went.  The webcam trained on Hilo Bay showed calm water, under a clear blue sky.  Several minutes later, however, the water began to flow out of the harbor into the bay.  As the water receded, the surface roiled, there were ribbons of foam, and the color of the water changed radically from transparent  blue to a very muddy, opaque brown.  Rocks and reeftops that had been submerged were now bared for a moment.  Then the water surged back toward the shore.

This cycle was repeated at least six or seven  times over the next hour and a half or so, and indeed, officials have said that smaller, less noticeable (to casual observers) surges continued for many hours.  When the tsunami warning was lifted, just before 2 PM, evacuees were allowed to return to their homes and businesses along the coast, but the beach parks remained closed.  Everyone was warned not to venture into the ocean, due to the possibility of unpredictable and potentially strong currents.

In Hilo Bay, the largest surge turned out to be just over one meter high.  There was no breaking wave, but the surge did wash over the breakwater, and briefly covered a dock in the harbor.  Although we did not witness it, we heard reports that the tsunami  swelled into the mouths of the two rivers that empty into Hilo Bay, surging upstream and turning the river waters very muddy.  As the mass of sea water pushed into the rivers, it uprooted vegetation along the river banks, and carried it back out to sea, along with rocks and other debris from the river bottoms.  Fortunately, though, the surge was insufficient to cause it to overflow the bay and the harbor to an extent that caused damage.  Hilo was spared, and so were all the other coasts of the Hawaiian Islands.

We don't have tsunami alerts very often, and the number of times a tsunami has reached our shores is relatively small.  Still, there have been several instances in which a tsunami large enough to do damage did come ashore in Hawaii, did cause destruction, and did cause injury and loss of life.  Island residents take tsunami alerts very seriously.

We have warning sirens on all of our coasts, and people know that when the sirens sound, they should immediately head inland and/or upslope and ask questions later!  Indeed, during yesterday's event, there were no reports of people who did not cooperate with the evacuation order.

For more information about the tsunami hazard in Hawaii, visit the Pacific Disaster Center's Tsunami page.  For tsunami alerts and data, visit the Web site of the Pacific Tsunami Warning Center, where you can also sign up for email alerts or subscribe to an RSS feed that will bring you alerts in real time.

Staghorn coral (Acropora cervicornis), a threatened species

by B. N. Sullivan

When we think of endangered or threatened species in the ocean, we usually think of sea turtles, or whales, or certain kinds of fishes.  Unfortunately, populations of some coral species also have been seriously depleted, and some are at risk for extinction.

According to the language of the Endangered Species Act of 1973 (ESA), a species is considered to be 'endangered' if it is in danger of extinction throughout all or a significant portion of its range.  A species is considered 'threatened' if it is likely to become an endangered species within the foreseeable future.

The pretty Staghorn coral (Acropora cervicornis) in the center of the photo above is officially classified as a 'threatened' species.  Acroporid corals like this one are important reef-building corals, and they provide a habitat for fishes and invertebrates..

In the United States, this species is found in the Florida Keys, and along the Atlantic coast of Florida as far north as Boca Raton, but it is absent from U.S. waters in the Gulf of Mexico, according to the National Oceanic and Atmospheric Administration (NOAA).  A. cervicornis does occur in the western Gulf of Mexico, and also in the Bahamas, the Caribbean islands, and Venezuela.

In a few places (very few)  it is still possible to see large stands of this antler-shaped coral, but more often these days, the species exists only as small colonies, like the one in the photo above.  In fact, reef surveys have shown that, since 1980, populations of A. cervicornis have collapsed, declining by up to 98% throughout the range.

So, what is responsible for such a marked decline?  The number one threat to Acroporid corals is White-band Disease, a devastating, rapidly spreading disease that destroys the tissues of the coral.  The cause of White-band Disease is poorly understood, but the results are devastating.

A. cervicornis is "particularly susceptible to damage from sedimentation and is sensitive to temperature and salinity variation," according to NOAA. In addition, NOAA lists hurricanes, increased predation, bleaching, algae overgrowth, and human impacts among the factors that threaten Acroporid corals.

Fortunately, conservation efforts have been initiated to manage and protect what remains of the A. cervicornis population.  In some areas -- such the U.S. Virgin Islands, Puerto Rico, and the Florida Keys National Marine Sanctuary (FKNMS) -- restoration activities also have been undertaken following hurricanes, ship groundings, and the like.  Nevertheless, restoration efforts, such as re-attachment of broken coral fragments and attempts to culture and settle coral larvae, are painstaking and have had limited success.

What you can do:

• When you snorkel, dive, or go to the beach, NEVER stand on or touch coral.
• Do not collect coral, dead or alive.  (Federal and State regulations prohibit collection of all soft and hard corals.)
• Divers should maintain proper buoyancy, be careful not to kick corals when swimming over them, and keep gear items such as hoses, gauges, etc. secured so that they do not drag across the coral.
• Boaters should use mooring buoys wherever they are available.  If you must anchor, avoid doing so near coral; instead of throwing your anchor, swim it down and place it on sand.

The above rules apply to all corals, of course, not just Acroporid corals.

More information: NOAA Fact Sheet: Atlantic Acropora corals - 2-page 'pdf' file

Hawaii Marine Debris Action Plan: Much needed program is the first in the nation

by B. N. Sullivan

Yesterday was an important day in the world of ocean conservation, and particularly for Hawaii.   The U.S. National Oceanic and Atmospheric Administration (NOAA) officially rolled out its new Marine Debris Action Plan (MDAP) for Hawaii -- the first in the nation.  Implementation of the MDAP is intended to protect Hawaii's coastal communities and marine life from the thousands of pounds of marine debris that wash ashore each year, just like that in the photo at right. [Photo supplied by NOAA].

The new MDAP is described as "a comprehensive long-term plan to actively assess and remove plastics, derelict fishing gear, and other human sources of marine debris from coastal waters and coral reefs along the island chain."  The plan, which was developed as a cooperative effort among NOAA; federal, state and local government agencies; academic institutions; conservation organizations; private industry; and community groups, aims to provide a comprehensive framework for activities to reduce:

• the current backlog of marine debris
• the number of abandoned and derelict vessels
• land-based debris in waterways, and
• fishing gear and solid waste disposal at sea

According to NOAA: Numerous strategies and activities fall under each of these goal areas, many of them already underway by Hawaii’s marine debris partners. These include debris removal efforts, emergency response, prevention and outreach campaigns, as well as increasing research and technology development. Progress will be tracked and measured for each of these areas.

These efforts are very welcome, and we are so pleased that the Hawaii Marine Debris Action Plan is now formally implemented.  Marine debris is a global problem, of course, and we hope that the Hawaii MDAP will serve as a model for similar efforts elsewhere.

For more information about the new program: Hawaii Marine Debris Action Plan (HI-MDAP) - 2 page 'pdf' file

Also visit the NOAA Marine Debris Program on the Web for related information, photos, and videos.

[Photo Source]

NOTE: This article was included in the February 2010 Carnival of Aloha, a blog carnival with a Hawaii theme. Have a look: Preservation and Lots of Aloha Create an Interesting Carnival

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Related posts on The Right Blue:

• Do your part to reduce marine debris
• What's wrong with this picture
• Loggerhead sea turtles need further protection

Container ship damages Woodhouse Reef in the Tiran Straits

by B. N. Sullivan

Regular readers of The Right Blue surely must know by now that one of our favorite places in the world to dive is the Red Sea.  We lived and worked in the eastern Mediterranean region for many years, and during that time, we went to the Red Sea frequently for dive breaks.  When we had the time to do so, we would spend a week or more on a live-aboard dive safari boat.  More frequently, we stayed at Sharm el-Sheikh and used day-boat charters to dive the reefs of the southern Sinai peninsula and the Straits of Tiran.

During that period of time, we visited the area so frequently that we came to know the South Sinai and Tiran dive sites as well as we know our reefs back at home.  Those reefs are incredibly lush, teeming with life -- and very photogenic.  Some of my best underwater photos were shot in the northern Red Sea.  It's been a few years since our last visit there, but our fond memories of the area have not dimmed.

All of  those reefs happen to be situated in or near very busy commercial shipping lanes.  The Tiran Straits separate the Gulf of Aqaba from the rest of the Red Sea.  All ship traffic heading to or from the busy ports of Eilat, Israel, and Aqaba, Jordan must thread their way around the reefs as they pass through that narrow passage between the coasts of Egypt and Saudi Arabia.  This week we learned that Woodhouse Reef, one of the four spectacular reefs in the Straits of Tiran, was seriously damaged when a 40,000 ton container ship ran aground on it on December 31, 2009.  The news made our hearts ache.

Underwater cameraman Tom Osborn dived at Woodhouse a few days after the ship ran aground there and filmed the damage.  In an article about the accident on the British Web site Dive Magazine, Tom Osborn relates what he saw:

"All of the reef in the area of the collision has been destroyed. It resembles a chalk quarry with fresh white lumps of rock scattered everywhere.

"You can see underwater that large sections of the container's hull has been crushed and sliced open from the force of the impact. As the ship smashed into the reef, she damaged huge chunks of the reef plate near the surface.

"An area approximately 30m wide and 20m long has tumbled away in sections down the steep slope of Woodhouse Reef like an avalanche, destroying any living coral below to a depth of at least 45m. At 35m you can clearly see a large slab of reef plate that used to be near the surface."

Here is a sample of the video shot by Tom Osborn that shows some of the devastating damage to Woodhouse Reef:

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

Leviathan cowries: Becoming scarce in Hawaii?

by B. N. Sullivan

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.

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.

World Oceans Day: Our Oceans, Our Responsibility

Today, June 8, is World Oceans Day. The theme of this year's World Oceans Day is "Our Oceans, Our Responsibility." Please take some time today to learn something about the ocean, and to reflect on how essential it is that we all do what we can to preserve and protect ocean environments -- for the health and well being of the entire planet.

We have the good fortune to live near the ocean, and we have spent countless hours in, under, and near the sea. Our perspective as divers has prompted a special interest in certain issues related to ocean health and conservation.

We decided that today, World Oceans Day, would be a good day to reprise some of what we have written in the past two years about ocean conservation issues. Here are some examples of our concerns:

• Do your part to reduce marine debris
• More on marine debris (with pictures of what we have seen underwater)
• Sea turtle conservation
• Responsible vs irresponsible spearfishing

We hope you are wearing something blue today to commemorate World Oceans Day. (Make sure it's The Right Blue!)

Here is a lovely video with images of the ocean and some of its inhabitants. We hope you enjoy it.



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

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.

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

Warm Geothermal Springs on Puako Reef

by B. N. Sullivan

The Big Island of Hawaii, where we live, is volcanically active. Kilauea Volcano, in the southern part of the island, has been erupting continuously since 1983, sending lava down its flank and into the ocean. Mauna Loa, another active volcano on the island, erupted most recently in 1984, and could erupt again at any time.

The coastline at Puako, where we dive most often, was formed by an old lava flow from Mauna Loa. The layers of hardened lava flows run well beyond the shoreline, extending seaward below the surface of the ocean to form the volcano's submarine flank. The old lava flows also form the substrate for the wonderful coral reef that fringes that particular section of the western coast of the Big Island.

Molten rock -- called magma -- moves along constantly underground beneath the volcanoes, and far below the reef and the sea floor. Here and there, cracks have formed in the substrate beneath the reef. When that happens, sea water seeps down and mixes with hotter fluids closer to the magma. That warmed sea water then rises back up toward the surface.

About 15 years ago, we discovered a couple of spots on the reef at Puako where this geothermally heated water rises up through chimney-like vents in the reef, creating warm springs. The photos on this page show one of those vents. I know it doesn't look very impressive, especially in the first in the photo, but we find these sources of volcanically heated water on the reef quite fascinating. [Click on any of the photos for a larger view.]

We first noticed this one, and another about 50 meters away, by their appearance. These vents are relatively small, but they are eye-catching to divers. They are situated in a broad coral garden dominated by a certain species of finger coral (Porites compresa). In fact, in that area, that species of coral is so dense that it uniformly and completely covers the substrate for acres.

Amidst that large stand of finger coral a couple of spots stand out, because they look different. There are deep holes, literally, in that dense forest of finger coral, and the holes are surrounded by a crust of very different looking corals.

It was the unexpected interruption of the field of finger coral that first caught our eye. We swam over to have a better look at these anomalies, and that's when we discovered that the crusty looking corals actually were arrayed around holes in the reef. When we hovered directly over the holes to peer inside, we felt the warm water emanating from below. We understood right away that these holes were venting geothermally heated water. It was an exciting find.

On one occasion, we showed the vents to a marine biologist friend who was visiting and diving with us. When she returned to Honolulu, she in turn told some oceanographer friends about these geothermal vents in Puako Reef. The news traveled through the grapevine, I guess, because we then got a call from someone at NOAA who asked if we would be willing to serve as dive guides to some researchers who wanted to have a look at the vents the next time they visited the Big Island.

We agreed, of course, and a party of three divers arrived in Puako several weeks later. We led them to the vents, where they took some photos, and some water samples. Once we were back on shore, they said these vents probably were not very important. In any case, they did say that they would let us know what was in the water samples, but then we never heard from them again.

We concluded from the silence that, indeed, 'our' little geothermal vents were not scientifically important. Still, we always have enjoyed this little underwater curiosity on our reef.

In this final photo, at left, our friend Dan is poking his head and shoulders into the larger of the two vents. I had asked him to pose for a photo near the mouth of the vent, to provide a reference for the size of the opening. Dan decided spontaneously that this posture would demonstrate the size better than simply posing beside it! (Thanks, Dan.)

In fact, the photo also demonstrates something besides the size of the vent opening. It should tell you that the water emitting from the vent is warm, but not hot, else Dan would not be able to actually enter the space like that! Using the temperature indicators on our dive computers, we have measured the temperature of the water coming out of the vents on many occasions. It varies, but always is in a range between 27-29 C (about 81-83 F). In other words, it is always several degrees warmer than the ambient water temperature, which typically ranges from about 24 C (75 F) in late winter to 27 C (80 F) in late summer.

Some of the reef critters seem to have discovered these vents. On numerous occasions we have spotted sea turtles hanging out around the edges of the vents. We also have seen any of several species of crab, and even the odd slipper lobster, snuggled down into the hole, clinging to the stony side of the vent, and at times we have seen clusters of sea urchins ganged up along the rim.

We, too, have taken advantage of this relative warmth, especially after long, deep dives. Making our way to our exit point, we can choose a route via one of the vents, and take turns hovering in the warm water for a few minutes. Ahhh.

Collecting Cone Shells: Special Handling Required

by B. N. Sullivan

In the last several posts we have been talking about collecting sea shells, and how divers can find shells underwater.

We strongly discourage the taking of live shells from their habitat. Taking live shells depletes populations by preventing the creatures living inside from reproducing. It also can disrupt the ecological balance of the habitat, since these creatures have roles as both predators and prey.

Previously, we offered a few tips on how to figure out if there are creatures living inside a shell. Today we would like to add a word of caution, particularly in regard to Cone Shells (Conidae).

There are hundreds of species of Cone Shells. The shells are attractive, and popular with collectors, but you should know that the snails that build and inhabit Cone Shells are venomous. Handling a live Cone Shell can result in being stung.

The Cone Shell snails are carnivores: some prey on other mollusks, others eat worms, and still others actually prey on fish! The snails have a structure that works a bit like a hypodermic syringe. They produce a venom that contains neurotoxins. They inject the venom into their prey through hollow stingers. (Technically, the 'stingers' are tiny, harpoon-like radula teeth.) Depending on the species, the venom either kills or immobilizes the prey.

There have been numerous cases documenting Cone Shell envenomation in humans. Depending, again, on the Cone Shell species, and also on the site of the sting, the result can range from pain, to paralysis, to death! So, if you see a Cone Shell in the water, understand that it is a venomous creature, and approach it accordingly.

If you are going to handle a Cone Shell to see if it is alive, pick it up carefully by the crown -- that is, the broad end of the cone. The stinging part is in the proboscis, which is at the 'nose' of the cone. Better yet, use something inanimate as a tool to flip over the shell so that its aperture faces upward. You may immediately see some part of the snail, but even if you don't, you should wait for awhile to see if the animal appears and tries to right itself.

If you find shells -- including Cone Shells -- while diving, it's convenient to carry them in a small mesh bag that you can clip to a D-ring on the outside of your vest. In any event, do NOT put a cone shell into your pocket or carry it in your hand, even if you think it is empty -- just in case!

We recommend that divers (and others) who are interested in collecting shells learn something about the creatures that formed the shells and live inside them. An understanding of how and where they live, what they eat -- and what eats them -- not only facilitates knowing where to look for them, it also provides the collector with a better appreciation of how the creature fits into the ecosystem. Today we add another item to this list of reasons to learn something about these creatures: your own self-protection.

About the photos: I took these macro photos of a live Mediterranean Cone Shell (Conus mediterraneus) on a sand flat off the coast of Dhekelia, Cyprus. As far as I know, this is the only Cone Shell species native to the Mediterranean Sea. The shell is relatively small -- about 3 cm (1.25 in). By the way, despite its appearance, that brownish structure sticking out near the wide end of the shell in the second photo is not the 'stinger'. It is the snail's operculum - a sort of lid that the snail uses to close over the shell aperture for protection when it retracts into the shell. The operculum is hard, made of material similar to our fingernails.

Curiously, we have never found an empty Mediterranean Cone Shell, so we have no examples of this shell in our collection. Fortunately, we do have several nice photos of the living species. Some long-time readers of The Right Blue may recall another post featuring this species, from 2007: Muck diving - The tale of the cross-eyed cone shell

On Sharks, Spearfishing, and Senseless Killing

by B. N. Sullivan

Over the years we have had many encounters with sharks while diving. We have told quite a few tales about sharks here on The Right Blue. Our readers always seem to enjoy our stories and photos of sharks, and a quick glance at the list of keywords that bring search traffic to The Right Blue tells us that a lot of people are looking for information about sharks every day.

It should be clear to anyone who has read our tales about sharks that we enjoy seeing them in the ocean. We do not fear them, but we do respect the sharks' role as apex predators in the hierarchy of ocean life. Sharks have great value to the overall ecology of the sea.

Without question, the shark species we have encountered most frequently is the Whitetip Reef Shark (Triaenodon obesus). We have seen this species regularly in our home waters around Hawaii, and in virtually every tropical reef environment we have visited around the world. We have seen Whitetips 'sleeping' in cavelets, on ledges, and on sandy bottoms. We have seen them actively and expertly hunting at night -- an impressive sight, indeed. Mostly we see these elegant animals lazily cruising the reefs, just like we do when we're diving.

We have never seen or heard of a Whitetip Reef Shark harming a human. They are not an aggressive shark. Neither are they valued as food for humans.

So, imagine our complete dismay and disgust when we learned recently that a Whitetip Reef Shark was senselessly killed by divers who were spearfishing at Puako, Hawaii. Here is an excerpt from this sad story, as it appeared on a local news blog called Hawaii247.com:

A couple of weeks ago, a resident Whitetip Reef Shark, known to countless Puako scuba divers, was speared and dragged out of the water along Puako Beach Drive.

A Puako resident who asked the young spearfishermen if they planned to eat the shark reported that they didn’t know what to do with it and that they had just shot it because they could.

As the animal thrashed around in a tidepool with a spear through it, they were unconcerned about its fate. It is likely that it died and was washed out to sea by the surf in the night.

The market value of a single shark pales in comparison to its value on the reef, alive and serving its function for reef ecology. As seemingly insignificant as the take of one shark may seem, these are not abundant animals, and, as they pose no danger to us, there is no justification for killing them for sport.

They had just shot it because they could. How brave. How sporting. NOT!!

Some time ago, a reader asked us, via The Right Blue contact form, what we thought of spearfishing. We sent him a reply privately, but made a note to address the issue in a blog post "one of these days." When the story about the senseless killing of that shark in Puako came to our attention, we decided that "one of these days" should be now.

Our attitudes and ideas about spearfishing have developed over time. Many years ago, in the early days of sport diving, many divers took along spearguns on nearly every dive, as a matter of course. It just seemed to be the thing to do. We never engaged in spearfishing, but many of our dive companions certainly did. Yet, it wasn't ever a question of engaging in target practice on reef fish, at least among the divers we knew. Instead, those divers speared food fish (or tried to -- they missed more often than not). If they managed to spear a grouper, sea bass, or flounder, all of us happily feasted on the catch.

Here in Hawaii, many people still spearfish. A good number of those look upon spearfishing as just another method to catch fish to put on the family dinner table. We have no quarrel with this kind of spearfishing, as a matter of principle.

We do have a big problem with spearfishing of the sort engaged in by the shark-killers in the above story. Fish -- whether sharks or angelfish or anything in between -- must not be used for target practice, ever. With spearfishing, there is no such thing as 'catch and release'. In most instances, a fish, once speared, will suffer substantial tissue and organ damage. It will not be able to survive, even if it is removed from the spear and let go. There simply is no excuse for spearing a fish you are not going to eat, just because you can. Of this we are certain.

Many conservationists oppose any sort of spearfishing by divers using scuba, reasoning that it provides the spearfisherman with an unfair, unsporting advantage over his game. They contend that spearfishing only should be allowed while free diving.

While we agree with the spirit of this point of view, we think it subsumes that spearfishing always is done just for sport. To us, "sport" implies just the kind of live target-shooting we abhor. We concede, of course, that this may be a semantic difference.

In truth, we are less concerned about whether a spearfisherman is free diving or using scuba than about his motivation. If we are talking about fishing for food, we don't see much practical distinction between spearfishing, throwing a net, or tossing a baited hook into the water.

Our core attitude about spearfishing is this: Don't spear anything you are not going to eat, and don't spear more fish (or other animals) than you need for a meal.

Divers, Cover Yourselves!

by B. N. Sullivan

For the past few months, virtually all of our posts here on The Right Blue have focused on interesting species of marine life we have come to know. Feedback on those articles has been positive: our readers seem to enjoy learning about creatures that inhabit the sea. But we also have been nudged by a few readers to get back to writing about diving -- as in, "Enough with the critters, already. Get back to diving stories!"

Well, okay then. How about some tips for divers?

Over the course of a few decades of diving, we have learned a number of useful things that, for one reason or another, are not taught to divers in formal training courses. The first is a simple rule that usually does not occur to divers until after they have had a bad experience or two. Cover yourselves!

In colder water, divers must cover themselves in drysuits or heavy wetsuits in order to retain body heat. But we believe that divers should be completely covered even when diving in warm tropical locations. These days, there are plenty of lightweight dive suits designed specifically for use in warmer waters.

We see many, many divers here in Hawaii -- mostly (but not only) tourists -- who seem to think that because they are in the tropics, they should just wear a shortie suit. We see them jumping into the water with their arms and legs exposed. Worse yet, some wear no dive suit at all, donning their dive equipment right over their bikinis. Guess what happens? Sooner or later, they get wounded!

It is very easy to brush against something -- a rock, a coral head -- even when you are trying to be careful not to touch anything. Sometimes it happens because the diver is not paying attention. Other times there is a little surge, just at the wrong moment. In any case, sooner or later some part of your exposed anatomy will collide, however briefly, with something in the water, and you will get cut or scraped.

In addition to those kinds of bumps and scrapes, it happens that there are many critters in the water that can bite or sting. Some are very tiny -- stinging plankton so small that you cannot see them in the water column -- so you cannot take evasive actions. Other are big enough to spot -- jellyfish come to mind -- but even then, you run a risk of being stung. Just because you see the critters doesn't mean you can count on completely avoiding contact.

The best way to prevent many of these inadvertent stings and scrapes is to wear a full suit that covers you from your wrists to your ankles. Wear boots or neoprene booties inside your fins. And wear gloves.

Now, we know that many dive operators discourage or even prohibit divers from wearing gloves. We also know the reason for that: they don't want to encourage divers to pick things up or handle them, and they figure if the divers are not wearing gloves, they may be less inclined to touch things.

Fair enough, but short-sighted. There are just too many situations where the protection afforded the diver by gloves outweighs the momentary protection of the reef and its critters afforded by bare-handed divers.

We think of it like this: we're grown-ups. We know we shouldn't recklessly handle things that dwell underwater. We know that touching corals (and many other things) can damage them. We promise we won't do that -- not because our hands are bare, but because we know better.

At the same time, what happens if we are shore diving and need to grab onto rocks at our exit point? We can very easily get cuts and scrapes on our hands, that's what.

If we are diving from a boat, what happens when we need to hang onto a mooring line or an anchor chain in order to remain stationary for our safety stop? Lines and chains that have been in the water for awhile are certain to be covered with algae, hydroids, and even teeny-tiny crustaceans. If you don't believe me, just have a look at the second photo on this page -- a 1:1 macro shot of an actual mooring line, totally encrusted with an entire ecosystem of its own! Hanging onto such a line is going to disrupt some of those things anyway, regardless of whether your hands are bare or gloved. But hanging on with a bare hand will really hurt. Said teeny-tiny crustaceans will cut your hand like little razors, and if you happen to grab onto a hydroid, you will know it, believe me. They sting like a son-of-a-gun -- and you will never forget the experience!

So then, even if you don't want to wear gloves for the entire dive, do carry a pair in your pocket at all times, just in case you have to hold or grab onto something for your own safety.

Dive like grown-ups. Cover yourselves completely to protect yourselves from scrapes and stings; but at the same time, do keep in mind that being covered (and thus protected) does not excuse you from responsibility for avoiding physical contact with the reef and the creatures that call it home.

Fish Tales: Encounters with the Napoleon Wrasse

by B. N. Sullivan

Imagine that you are on a dive boat in the Red Sea. The boat has just tied up to a mooring at a place called Jackson Reef in the Tiran Straits. All geared up, you jump off the stern platform of the boat and begin your descent. As you drift down gently through the water column, something off in the distant blue catches your eye. At first all you can make out is a hulking shape that looks vaguely like a Volkswagen beetle, and it is moving toward you. As it lumbers along, the shape tilts this way and that, and as it gets closer you are able to make out pectoral fins, big eyeballs, and huge fat lips. You realize it's definitely not a Volkswagen; it's a great big fish - A Napoleon Wrasse.

Earlier this week, for Wordless Wednesday, I posted a photo of a Napoleon Wrasse. Readers commented on the size of the fish, on its shape, and on its prominent eye.

These guys definitely are big: adults usually are close to four feet in length, although I read somewhere that there have been reports of older males of the species occasionally reaching a length of about six feet. Females tend to be smaller. In any case, they are said to be the largest species in the Wrasse (Labridae) family.

They are heavy-bodied, and weigh several hundred pounds. Because of their bulk, they usually lumber along, but make no mistake - they are capable of very quick speeds, too, at least over short distances.

Their eyes are large, and each can move independently. The eyes protrude and rotate in a way that might remind you of the ball turret on a World War II B-17 aircraft (without the gunner). When they are close to you, they tend to tilt to look at you with one eyeball, much as a chicken would.

The common name, Napoleon Wrasse, arises from the prominent bump that protrudes from the foreheads of fully grown adults, giving them a profile that is reminiscent of Napoleon Bonaparte with his hat. Another common name for the fish is Humphead Wrasse -- take your pick -- but in either case, the scientific designation for the species remains the same: Cheilinus undulatus.

These fish can live for thirty years or so, and they seem to have long memories. When we first began to dive in the Red Sea a few decades ago, dive guides there sometimes would entertain their clients by hand feeding boiled eggs to the Napoleon Wrasses. After awhile, once everyone finally realized that this was not an ecologically sound thing to do, this practice was banned.

Unfortunately, no one sent a memo to these fish to tell them not to expect boiled egg handouts from divers. For years after the practice of feeding them boiled eggs had stopped, the Napoleons still converged near dive boat moorings as soon as they heard the sound of the boats' engines approaching. There they would lurk until they spotted divers descending, at which point they would approach the divers at quite close range, hoping for a free snack.

Sometimes the Napoleons would do more than wait. If a diver reached into the pocket of his vest for any reason, the Napoleon would quickly swim right up to that diver in anticipation, sometimes nudging the diver with those great big fat lips. We've heard countless of stories of divers who had to physically push a Napoleon away from them repeatedly before the fish finally got the message that they had no eggs to hand out.

In an extreme case that we actually witnessed, a friend who was diving with us lost an important piece of gear to a Napoleon, and almost lost his hand as well.

For the benefit of our non-diving readers, let me first explain that these days, scuba regulators (the device that reduces the pressure of the compressed air in the cylinder so that it can be breathed) usually have two second stages, i.e., the part that includes the mouthpiece. The primary one will be used by the diver to breathe underwater. The secondary one, though fully functional, is a back-up. As such, it is usually attached to the diver's vest by a clip or similar means, or stuffed into a pocket.

So then, on this particular dive, the clip that usually held our friend's back-up second stage had broken. Rather than let the device trail behind him, he held it at waist level, cupped in his two hands, as he swam. Now, these devices come in a wide variety of colors. Our friend's happened to be white. (Can you see what's coming?)

Along came a Napoleon. It saw the round white shape cupped in our friend's hand and apparently mistook it for an egg. First the fish swam back and forth excitedly around our friend. Then it nudged him. Annoyed, our friend put out one hand to push the aggressive fish away. At that instant, the Napoleon lunged and snapped the white regulator out of our friend's other hand -- or tried to. The regulator was attached to a hose, of course. When the Napoleon bit, the hose partly detached and it began to froth like crazy from the rapidly escaping compressed air. That scared the fish, which went zooming past us with our friend's glove hanging from its mouth!

That was the end of that dive: time to initiate emergency procedures. A fourth diver who was with us immediately handed off his back-up second stage to our stricken friend so that he could breathe. Meanwhile, Jerry swam around behind him to turn off the valve on his cylinder, stopping the uncontrolled flow of air. Then, with the two divers sharing air, we all swam back to the boat.

Once on board, we inspected the damage. The hose had to be replaced, and although the white second stage that had been bitten probably could have been repaired, our friend announced immediately that he would replace it -- with a black one! No one ever saw the glove again, but our friend was happy enough to have relinquished it, since he still had his hand.

By the way, we have seen Napoleons elsewhere -- especially in the waters around Malaysia and Indonesia -- but only the ones in the northern Red Sea were so bold. The ones we saw in other places tended to keep their distance from divers. Apparently they had not been fed by divers. In fact a dive guide in Indonesia told us that Napoleons had been a favorite target of spear-fishermen there until quite recently; thus, they had learned to be wary of humans underwater.

About the photos on this page: Each image shows a different individual Napoleon Wrasse, and each was photographed on a different dive. I took all three photos in the Red Sea: the top photo was taken at Jackson Reef in the Tiran Straits; the other two photos were taken at Ras Mohammed, near the tip of the Sinai Peninsula. And in case you are wondering, the Napoleon in the third photo is not about to bite the leg of the diver on the left. It's an optical illusion created by the wide angle lens. The wrasse actually was positioned between the two divers.

What is the difference between 'endemic' and 'indigenous' species?

by B. N. Sullivan

When I write about the creatures we have come to know, I nearly always identify both their common name, and their scientific name, and of course I tell our readers where the creatures live. In some instances, I may also mention that a creature is 'endemic' to a certain place.

A reader recently asked, "Does endemic mean the same thing as indigenous?"

The answer is, "Not exactly." Let me explain.

When we say that a species is indigenous to a place, we mean simply that it occurs there naturally. It is a native. But a species can be indigenous to a number of places at once.

In contrast, if we say a species is endemic to a place, we mean that it occurs naturally only in that place. It is a native to an exclusive or limited area. It is not widely distributed, and won't be found naturally anywhere else.

Most species inhabit specific areas of the world, but not the whole world. When people think about animals on land, they intuitively know this. They know, for instance, that giraffes exist naturally only in Africa, and that the polar bears live naturally only in the Arctic. They would not expect to see a giraffe wandering around wild near Hudson Bay, nor would they expect to see a polar bear in Kenya. Yet there are many animals that are much more widely distributed than giraffes or polar bears. Think of squirrels -- or rats!

In the sea, it is the same. Some marine animals (and plants) occur naturally only in the Caribbean, or the Mediterranean, or Hawaii, for example. Other species are found in a wider range of places.

Here in Hawaii, we have a high percentage of endemic species, compared to other places in the world. This is true both on land and in the ocean. Because the island chain is so geographically isolated -- separated from other land masses in every direction by thousands of miles of open ocean -- there has been less opportunity for species from elsewhere to wander here spontaneously and establish themselves. Likewise, it has been difficult for many species that have evolved here in Hawaii to make their way to other areas of the world.

The photos on this page show examples of fish species that are found in Hawaiian waters. The first photo on this page shows a fish called the Saddle Wrasse (Thalassoma duperrey) being serviced by a smaller fish called the Hawaiian Cleaner Wrasse (Labroides phthirophagus). Both of these species are endemic to Hawaii. They occur naturally nowhere else in the world. Each has 'cousins' of the same genus in other regions. Some of those cousins look quite similar, but they are not anatomically identical. I took the photo at Puako, Hawaii.

The second photo shows a small squadron of Moorish Idols (Zanclus cornutus). These fish are indigenous to Hawaii -- they occur here naturally -- but they are not endemic. They also occur naturally elsewhere in what is known as the Indo-Pacific region and the tropical eastern Pacific. Indeed, we have seen them and photographed them in quite a number of places. These four were photographed at Honaunau, Hawaii.

When we speak of an animal's provenance, there is a third category that is important: the introduced species. Introduced species are those that do not occur naturally in a given place. They are brought there -- introduced -- from somewhere else. Sometimes this happens accidentally (as when a caged parakeet escapes), or when an animal hitch-hikes to a new location on a ship or plane, and manages to establish itself there. In other instances, animals are introduced deliberately, for a variety of reasons. Here in Hawaii, for example, there are a number of game birds that were intentionally introduced decades ago for the benefit of sport hunters. Other species were intentionally introduced as a food source.

In the third image on this page are some Bluestripe Snappers (Lutjanus kasmira), photographed at Puako, Hawaii. These fish were intentionally introduced from the Marquesas in the 1950s as a food fish. As so often happens, their introduction had unintended consequences. Some people in Hawaii do fish for them, and we do see them for sale in some fish markets, but they are not exactly prized. Worse, they have proliferated greatly and they compete with other, more valuable fish. It is also believed that they have contributed to the depletion of the population of a particular kind of crab upon which they prey.

So, to review: Endemics are native to, and live naturally, only in one place; indigenous species are native, but may be more widely distributed; introduced species are 'immigrants' of a sort.

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.