Seeing stars: A new descriptor for Linckia sea stars?

by B. N. Sullivan

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

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

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

Serene Waipiʻo Valley on Hawaii's Big Island

by B. N. Sullivan

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

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

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

Seeing stars: Linckia multifora

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

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

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

Seeing stars in the sea

by B. N. Sullivan

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

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

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

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

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

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

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

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

What do you think when you see the ocean?

by B. N. Sullivan

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

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

That's right, I said dead end!

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

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

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

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

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

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

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

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

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

Butterflyfishes on a North Kohala reef

by B. N. Sullivan

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

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

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

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

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