Hymn to the Sea

If the video does not play or display properly above, click here to view it on YouTube.
Hat tip to Tony Berkman at FriedEggs.com, which is where I first saw this video.

Who's sleeping on the job around here?

by B. N. Sullivan

I know, I know -- it's been awfully quiet here at The Right Blue for the past couple of weeks.  If there were crickets underwater, you'd probably hear them chirping!

I haven't been sleeping on the job.  I've been traveling, and then catching up on stuff related to my day job, so I've neglected this space.  I'm about ready to get busy here again -- posting new photos, creature features, and articles about the marine environment. -- so please stand by.

Meanwhile, if you haven't already done so, do check out Jerry's very active Twitter stream @therightblue. He's been busy there, keeping our followers informed about developments surrounding the horrendous oil well catastrophe in the Gulf of Mexico, among other ocean-related topics.

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.

Purple sea slug (Hypselodoris apolegma)

by B. N. Sullivan

Isn't this a pretty little critter?  It is  Hypselodoris apolegma, a nudibranch from the family Chromodorididae.  It doesn't have a standard common name, so we just call it the purple sea slug. This attractive nudibranch lives in the western tropical Pacific region.

H. apolegma feeds on sponges. It seems to prefer a dysideid sponge of the genus Euryspongia, but it may feed on other sponges as well.

Like many nudibranchs, the purple sea slug lays its eggs in a ribbon-like mass. The egg mass of H. apolegma is yellow.

The creature's striking coloration makes it an attractive subject for underwater macro photography.  I photographed this one off the northern coast of the Indonesia island of  Sulawesi, in the Celebes Sea.  This specimen was about 3 cm long (about an inch).

The species fact sheet for H. apolegma on the Australian Museum's authoritative Sea Slug Forum describes this creature's coloring as follows:

The background colour is a rich pinkish purple with a white border to the mantle. At the edge of the mantle the border is solid white but inside this is a region of varying width in which the white forms a reticulate pattern gradually merging in to the pinkish purple. The rhinophore stalks and the base of the gills is an intense purple, the rhinophore clubs and the gills are orange yellow.

Yep, that's our purple sea slug!

Visit the Hypselodoris apolegma species page on the Sea Slug Forum for more information and photos, including feeding records, mating, and the egg mass of this species.