Diving the Kona Coast: September 2011

Thursday, September 29, 2011

Whitetip Reef Sharks Abounding

Since around March, there has been an uptick in the presence of Whitetip Reef Sharks (Triaenodon obesus) residing just south of the Two-Step at Honaunau Bay. During the daylight hours they have been residing under ledges or in pukas to rest, occasionally venturing out to give snorkeling tourists a possibly unwelcome thrill. There are at least two of them as I saw a pair together. All the ones I have seen have been female.

The shark in the first two photos is small, around 3' in length. Betty found it in a sand-bottomed puka at around 20' depth. This one was quite confident in the security his shelter gave her and sat still for photographs which I greatly appreciated.

A couple weeks later I was in shallow water by myself and decided to check out a ledge where I had seen a turtle resting on an earlier dive. Turtles often stake out sheltered areas to rest in and return to them regularly. On this day, I turned the corner to find the six-foot shark pictured above where I expected the turtle to be. She quickly roused and came in my direction. In the midst of being startled I took this picture which is blurry due to me recoiling in shock as I tripped the shutter.

The big gal swam around me for awhile, clearly displeased at my presence. While I didn't check my gauge, depth had to be around 10-12'. You can see the play of sunlight on the fish as well as the surrounding reef which generally occurs only near the surface.

One last shot. Notice how ragged the tip of her dorsal fin is. She's been around the block a few times!

Day Tube Anemone

The Day Tube Anemone (Cerianthus sp.) is a creature that looks plant-like but is, in fact, an animal. It lives within a long slimy tube that it forms from adhesive threads that it secretes. The tube is a very tough, durable structure that is open at both ends and is situated vertically in the substrate. The tentacles of the creature protrude from the upper end of the tube while the rest of the creature lives in and under the tube.

This particular species lives in deep water. This individual is at 117' depth in Honaunau Bay. Some types of tube anemones have survived in aquariums for over a hundred years. This one has been around ever since I started diving Honaunau around 12 years ago.

Among anemones, the tube anemones are unique in having two sets of tentacles. Short, oral tentacles surround the mouth while longer food-gathering tentacles are along the periphery. There may be several hundred tentacles in all. The two tentacle varieties can be distinguished in the photo above.

Tuesday, September 20, 2011

Aetobatus narinari at Honaunau

For months I have been following the progress of a young Spotted Eagle Ray (Aetobatus narinari) which has made Honaunau Bay its home. However, while taking these photographs, I saw another ray of similar size nearby. The presence of two rays instead of one certainly accounts for the frequency of sightings which have become almost routine for SCUBA and freedivers in the bay.

All these photos are of the same individual, the other ray staying out of range. This oneis growing up nicely but still not full-sized.

As graceful as the fish are when swimming, they still have to eat. And when they do, it's anything but graceful, diving headfirst into the sand and creating a dust storm as they search for mollusks and crustaceans.

The Manta's Shadow, Part III: The Douglas F4D Skyray

I've always loved airplanes. My dad was a mechanic at an Air Force Base, I lived near two active bases in my life and my step-son is a Sergeant in the USAF. Fish and airplanes have some things in common. Fins, for one. But, also, they are (usually) streamlined and come in a wide variety of shapes, sizes and colors.

As a boy, I used to build plastic airplane kits and one of my favorites was the Skyray. It was sleek and fast and unusual in that it had no horizontal tail surfaces like most planes. The wings were broad, rounded and sharply swept giving it the shape of a certain marine animal known and loved along the Kona Coast. Quoting Wikipedia: "The design was named for its resemblance to the Manta ray fish".

Whether the aircraft designers used the shape of the manta for inspiration is not known but probably unlikely. However, the appearance and name of the plane reinforced the manta's place in the public psyche. Notably, it was the first carrier-based aircraft to hold the world's absolute speed record (752.943 mph) and the first naval fighter that could exceed Mach 1 in level flight. The plane also set a time-to-altitude record flying from a standing start to 49,221 feet in 2 minutes and 36 seconds all while flying at a 70 degree pitch angle which is incredibly steep.

New Links

Recently, two organizations have approached me asking if they could use my photographs on their sites. Both are not-for-profit, conservation/educational entities and I was happy to help and, frankly, quite flattered by the nice treatment they gave to my material.

I have added links to both their sites. The first is a Polish site, Nyskie Towarzystwo Ochrony Zweirzat used a few of my moray eel photos for an article. The site has a built-in translator for those of you not fluent in Polish. The name of the organization in English is Animal Protection Society Nyskie and they are involved in animal rescue work.

The second site is MarineBio which is building an ambitious marine species database. The link leads to their site but they also publish a very interesting blog. The organization looks fascinating and makes me wish I could go back in time and follow that career in marine biology I dreamed about when I was a kid watching Jacques Cousteau on TV.

Anyway, give the sites a look! You'll be glad you did.

Thursday, September 8, 2011

Dendrodoris rubra

I found this attractive nudibranch in a small cave at Honaunau Bay which I poke into often. This critter was around 2.5 to 3 inches in length which is pretty large for a Hawaiian nudibranch. It was also pretty active, sliding along the cave floor at a pretty good clip for a slug. This is the first one I have ever seen although the guide books don't indicate that it is uncommon.