Mandarinfish & other dragonets. Part 9 of my documentary, "Mucky Secrets", about the fascinating marine creatures of the Lembeh Strait in Indonesia. Watch the full 90-minute documentary at    • Mucky Secrets (full) - The Marine Cre...  

In this video I study dragonets including the amazing mandarinfish. Dragonets are benthic animals, meaning that they live on the seabed. They thrive in the muck of Lembeh. Dragonets are well-adapted to benthic life. They are well camouflaged and at night they bury their bodies. The eyes and gills are placed high so only they remain above the sand.

The fingered dragonet, Dactylopus dactylopus, is found in the Lembeh Strait. The first ray of each pelvic fin is effectively a limb or "finger" that the dragonet uses to walk along the seabed and dig for food. The male has warpaint-like facial markings and has long filamented rays on its dorsal fin that it holds forward when walking. The female has a bright orange upper lip.

The orange-black dragonet, Dactylopus kuiteri, is very similar. We encounter an adult and juvenile in close proximity, feeding on the seabed.

The Morrison's dragonet, Synchiropus morrisoni, shuffles around the seabed without the aid of the separated fin rays.

A similar species of dragonet, the mandarinfish, Synchiropus splendidus, stays well hidden amongst shallow hard corals during the day. At dusk the males eagerly seek out female mates. During the hunt they hold their first dorsal fin aloft as an advertisement to the females and a warning to competing males.

When a mate has been found, the female rests on the larger male's pectoral fin and the couple rise up together from the reef. At the peak of their ascent they simultaneously release sperm and eggs and then make a dash for cover as the spawn drifts away in the current.

This frenzy of sexual activity typically lasts some thirty minutes until nightfall. If fertilized, the eggs will hatch about a day later and the tiny larvae will drift for a further week or two before settling onto the bottom to begin their benthic life.

There are English captions showing either the full narration or the common and scientific names of the marine life, along with the dive site names.

The full Mucky Secrets nature documentary features a huge diversity of weird and wonderful marine animals including frogfish, nudibranchs, scorpionfish, crabs, shrimps, moray eels, seahorses, octopus, cuttlefish etc..

Thanks to Kevin MacLeod of http://www.incompetech.com for the music track, "Comfortable Mystery", which is licensed under a Creative Commons Attribution 3.0 Unported license.

Thanks to the staff and keen-eyed divemasters of Two Fish Divers (http://www.twofishdivers.com), for accommodation, diving services and critter-spotting.

The video was shot by Nick Hope with a Sony HVR-Z1P HDV camera in a Light & Motion Bluefin HD housing with Light & Motion Elite lights and a flat port. A Century +3.5 diopter was used for the most of the macro footage.

I have more scuba diving videos and underwater footage on my website at:
http://www.bubblevision.com

I post updates about my videos here:
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http://google.com/+bubblevision
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  / bubblevision  

Full list of marine life and dive sites featured in this video:

00:00 Fingered Dragonet (male), Dactylopus dactylopus, Hairball
00:30 Fingered Dragonet (female), Dactylopus dactylopus, Retak Larry
01:06 Orange-black Dragonet, Dactylopus kuiteri, Aer Perang
01:13 Orange-black Dragonet (juvenile), Dactylopus kuiteri, Aer Perang
01:36 Orange-black Dragonet, Dactylopus kuiteri, TK 1
02:07 Morrison's Dragonet, Synchiropus morrisoni, Nudi Falls
02:32 Mandarinfish, Synchiropus splendidus, Tanjung Kusu-Kusu