Fine perch for a sea turtle

Green Sea Turtle perched on the coral at Pulau Sipadan, Malaysia

by B. N. Sullivan

Sea turtles have a knack for finding comfy resting places on the reef.  Earlier this year I posted a photo of a turtle who had plopped down on a bed of soft corals to take her rest.  Here we have another Green Sea Turtle, perched this time on a table coral that jutted out from a steep bank.

We spotted this turtle at the outset of our dive, and as we passed by the same spot about an hour later on our way back to the boat, she was there again -- or still! -- surveying the scene.  She looked so comfy and at ease that we reckoned this must be her regular post.  We know from having observed the behavior of individual turtles in Hawaii over periods of years that each effectively "owns" a particular spot on the reef, returning to the same rocky shelf, or cavelet, or depression in the coral day after day over a long span of time.

To us, this turtle looked a bit like a sentry posted in a watchtower.  From the outcropping, she  had an unobstructed view of the entire bank -- left, right, up to the surface, and down into the gloomy depths -- a fine perch for a turtle.

Sea Plumes in the Caribbean

A Caribbean Sea Plume (Pseudopterogorgia sp.)

by B. N. Sullivan

In earlier posts (such as this one about the Red Sea) I have noted that underwater scenery varies a lot from one region to the next.  Fauna characteristic of a given area can provide instantly recognizable clues to the location of a photo.  For the Caribbean and adjacent tropical waters, one of those clues is the presence of Sea Plumes like the one in the photo above.

Sea Plumes can be found on patch reefs and along dropoffs throughout the Caribbean, as well as some areas of the south Florida coast, the Keys, and in the Bahamas [which are technically in the Atlantic, not the Caribbean].  They are a type of Gorgonian soft coral, in the same taxonomic Order as Sea Fans and Sea Whips.

The polyps of Sea Plumes tend to be arranged in rows along their branchlets.  The colony has a furry or fuzzy appearance when the polyps are extended, as in the photo above.  When the polyps are retracted the branchlets have a smooth, stick-like appearance.  Sea Plumes like to establish themselves in areas where there is some tidal current or other flow that facilitates feeding.  To feed, the polyps catch plankton and other nutrients that pass over them.

Sea Plumes come in an assortment of colors -- mostly greens and browns, but also purple.  The color depends on the presence or absence of zooxanthellae in their tissues.

Some species grow more than a meter tall.  The one in the photo above, which I photographed at Cayman Brac, was about a half meter tall and its branches spread nearly a meter wide.

The Yellowbar Angelfish (Pomacanthus maculosus)

Yellowbar Angelfish (Pomacanthus maculosus), Red Sea

by B. N. Sullivan 

If you dive near tropical reefs in the Indian Ocean or the Red Sea, you may encounter the Yellowbar Angelfish (Pomacanthus maculosus).  Often you will see them nibbling on a sponge,  or pecking at corals and algae-covered rocks.  In our experience, they don't seem to be fearful of divers, often swimming right up to have a look at us.  They are known to be territorial, so perhaps they approach divers to judge if they are friend or foe.

The adult of this species, pictured above, grows to a rather large size (for an angelfish!) -- up to about 20 in (50 cm).  The bright yellow patch on their flanks makes them easy to recognize.  Legend has it that the splash of yellow depicts a map of Africa.  That may be a bit of a stretch, but it accounts for the fact that an alternate common name for this species is Map Angelfish.  In any case, the exact shape of the blotch is unique to each fish, rather like a fingerprint.

The individual pictured above was photographed in the Red Sea, near Sharm el-Sheikh, Egypt.