On the work front, things are quite busy with spring break in full swing. Most of our programs are filled to or over capacity, so I haven't been getting too much time off, and you all know what that means - recycled pictures from last week's scuba trip!

Some rather lumpy coral polyps. During the day they all tuck in like this to expose the algae living in their skin, as they get up to 98% of their food from their symbiotic relationship with this algae. We often use this relationship as an example of sustainable living in our CAOS programs, as each partner's waste products are necessary for the other to live, forming a virtually closed nutrient cycle. The remaining 2% of the coral's food comes from plankton caught by the coral polyps at night. The polyps unfold to extend their stinging tentacles, so if I were to go back and take a picture of this same coral head at night, it would look very fuzzy.

This is a closeup of a sponge. Just like any kitchen sponge, these guys clean the area around them. They feed by filtering water through their bodies, drawing it in through the sides and out through the large hole on top. It is for this very reason that coral reefs can even exist - the sponges remove particles that would otherwise block the sunlight, allowing corals to grow. This removal of nutrients from the water also keeps algae from overgrowing the reef, as only self-sustaining, closed nutrient cycles like those found in the corals can survive. Also, they look pretty cool.

My apologies for the relatively bad picture quality on this one, but I didn't really feel like getting too close to this particular subject. For those not familiar with their marine carnivores, this is a barracuda. Barracudas are actually given a pretty bad reputation. Yes, they have sharp teeth, and yes, they have bitten humans in the past, but that's about as far as their interest in humans goes. People act like these guys are the Great Whites of the Caribbean (Great Whites also being vastly misunderstood, by the way). This fish is about 3-4 feet long and really quite skittish. It would like nothing more than to be rid of those darn humans with cameras and simply float along in peace. Vilification is not the answer, people!
And now for a Postcards first: pictures NOT taken by Andrea! These photos are both courtesy of Ollie, my dive buddy, and are of me swimming through the cave-tunnels described in last week's post.

