Tuesday, June 7, 2011

Glowing water-bioluminescent bay

Bahía Mosquito - better known to visitors as Bio Bay - is one of several bays in Puerto Rico that glow on dark nights because of tiny creatures called bioluminescent dinoflagellates. These half-plant half-animal organisms have a similar makeup to fireflies. The bay looks like any other except when you move a paddle or swim through it. We were in an electric boat that glowed blue when the engines were on. When fish or rays dart through the water, they appear to be glowing. 

Lights here are from shore where the next tour was waiting.

The glow in the upper left corner is from the bus headlights on shore. The blue glow in the center is a fish. The streaks on either side are from the boat's propellers.

The companies that run tours claim that the Vieques bay has the brightest concentration of these creatures, probably because there is less light pollution and the bay has a narrower entrance. The Spanish are actually responsible for the narrow channel. They attempted to close off the bay, believing the bioluminescence to be the work of el diablo. Instead the glowing creatures became more concentrated.

By the time I figured out the right exposure to get anything but black on the image, it was time to go. If you are curious, I shot at 3200 ISO, f4.5 at 6 seconds with the camera mounted on a monopod.  

The bay pretty much looks like next-door Sun Bay during daylight hours. 

1 comment:

  1. Nice. Our guides said that the reason it's better is that they're more concentrated & that's because of higher salinity, which results from narrow opening . . . Interesting phenom. Also that they glow because when agitated they blend two chemicals together -- is that what fireflies do/