Insane fish fry upwelling, Alor, Indonesia

Insane fish fry upwelling, Alor, Indonesia, originally uploaded by echeng.

October 31, 2011; 5:04pm - I've just surfaced from one of the most incredible dives of my life. We've been diving in the sound between Alor and Pura for the past few days, and the water has been rich with the critter life for which this area in Indonesia is well known. It has, however, been unusually cold—the coldest any of us have ever experienced while diving in Indonesia—and during one dive yesterday, our computers reported water temperatures of 15ºC (59ºF)! This is totally unheard of in this part of Indonesia.

Today's diving started out rather typically, with two productive critter dives. During one dive, we saw and photographed five different Rhinopias sp. scorpionfish. Three of them were new individuals, which means that the dive site, named "Mucky Mosque" for the mosque it is located in front of, is home to at least seven individual rhinopias (rather extraordinary for a single site). We decided to go back to a site called "Slugfest" for the third dive of the day. At the site are two pregnant xeno crabs (Xenocarcinus tuberculatus) and dozens of species of nudibranchs and other pretty sea slugs. About 45 minutes into the dive, photographer Julian Cohen and I were at around 85' engrossed in photographing one of the xeno crabs. Cold water had seeped up from the depths earlier in the dive, and there was a noticeable thermocline. Suddenly, we noticed a huge, milky, white cloud ascending from the deep. In no time at all, the white cloud enveloped us, and we saw that the gigantic formation was comprised of million—if not billions—of tiny fish fry. The fish cloud completely covered the reef, and vertically-blessed corals (like long wire corals) jutted outed of the milky mass like tall trees emerging from fog. As the giant school of fry hit the shallow reef, it changed formation, branching out into hundreds of rivulets, each snaking organically around any coral formations in the way. Tentacle movements were not unlike the water creature from the movie, "Abyss." With so much food in the water, reef denizens went berserk. Fish by the hundreds shot out into the water column, gulping down the little fry in a frenzy of feeding. But there were nowhere near enough predators to affect the overall population.

Photographer Julie Edwards was confused. "Nothing was eating them! I was expecting a whale shark to show up."

Indeed, the bulk of the huge mass of fry simply blanketed the reef in a virtual atmosphere of baby fish bodies. Unfortunately, all of us photographers had entered the water expecting to photograph tiny (individual) marine critters, and had configured our cameras as macro rigs. Since we couldn't take any pictures, we just sort of floated around, gawking in disbelief at the strange marine spectacle. A guide was carrying my 3D GoPro setup. I tracked him down in order to retrieve the camera, and captured some basic footage of the scene. The footage I captured pales in comparison with what we actually saw, but I was glad that I was at least able to capture some of it. I'll upload it when I return from Indonesia.