by Forest Rohwer, head researcher on the Microbe Team
Here at Kingman, sharks—lots of sharks—patrol the waters around the ship at night. Dinner is served, drawn by the lure of the ship’s lights. Every few minutes a needlefish makes a poor life choice and enters the killing field. There follows a frantic feeding frenzy, with the fish jumping to escape the snapping swarm. One wrong turn by the fish and its all over. A lot more entertaining than TV. Much of the Halloween party (see previous post) was spent rooting for either the sharks or needlefish.
Observing the feeding frenzy, as well as the noticeably more aggressive behavior of the sharks at dusk, dampens any thoughts of night diving. This means that we know very little about what happens on Kingman Reef at night. To watch the nocturnal life of the reef, Katie Barott and I have been setting up cameras to run remotely. After dark the reef really comes to life with invertebrates (shrimps, sea urchins, crabs, snails, etc.), most of which we never see during the day. Their primary activity seems to be feeding on the crustose coralline algae. Switch between the two photos and see if you can find all of the little creatures that are moving around.
We are also using a hydrophone to eavesdrop on the reef. The volume increases significantly at night, presumably because of all the cryptic animals moving about. We will be deploying the hydrophone on all of the islands we visit throughout the chain. Our hope is that the hydrophone can provide a rapid assessment of reef health. We have attached a sound file from Kingman so that you can listen in. (The link is at the bottom of the post.)
No bars or dance clubs to be found, but still the night life on Kingman is downright raucous.