Tag Archives: Caulerpa

Day 13: Marine debris and mangroves

Sunrise on Middle Caye

The project of the morning consisted of quantifying the marine debris that was washed up on the windward side of Middle Caye. At four sites we measured the amount of trash that the 14 of us could collect in 15 minutes. By weight, 50% of the debris that we gathered was plastic and another 21% was Styrofoam. 14% was rope and 15% was glass, rubber, or other materials. Overall we collected 41.22 kg of debris in one hour, which is especially significant because the shore gets cleaned every week. The amount of debris that we collected on a small portion of this small island far away from the shore was staggering.

In the afternoon we ventured through a stand of mangroves to the leeward side of the island to the back reef. We were there to collect data on coral colonies that the EBIO 319 students measured last year, but we were also able to explore the area. The large quantity of sand on the back reef made it a good place to find green algae. Most of the Caulerpa that I saw were either Caulerpa cupressoides (cactus tree algae) or C. urvilleana. The Caulerpa were often found near Penicillus capitatus and Udotea flabellum. I also saw a few examples of Dictyosphaeria cavernosa (green bubble algae) on corals and in sea grass.

While we were collecting debris I noticed a fair amount of filamentous algae on the rocks along the shore. I’m not sure whether they were from the Cladophoraceae or Derbesiaceae family. Some of them might have been Rhizoclonium riparium.

I forgot to mention yesterday that I found Caulerpa racemosa (green grape algae) on the windward back reef that we visited. The algae were in very shallow water right behind the reef crest. I also have seen examples of Acetabularia calyculus (mermaid’s wine glass) in the shallow water off of the dock.

Caulerpa racemosa on the back reef at Middle Caye
Caulerpa racemosa (green grape algae), turf algae, Halimeda, and brown algae on the back reef at Middle Caye
Acetabularia calyculus (mermaid’s wine glass)

Day 9: The Reef!

View of Glovers Reef from observation tower on Middle Caye
Patch reef in Glovers Reef

Today we traveled from the zoo to Glovers Reef. Glovers Reef is one of three atolls in Belize. It consists of four islands – Southwest Caye, Middle Caye, Long Caye, and Northeast Caye. We got to the island around 3:45pm and were able to snorkel for an hour before we had dinner. To our surprise, the water was like bathwater, especially right by the pier. It almost wasn’t refreshing, but being in the water was amazing.

Most of the sea floor that we saw was covered in sea grass. There weren’t any trees in the sea, but someone found a Penicillus capitatus, which is a species of green algae that looks like a paint brush. A little farther out, the sea grass gave way to a few patch reefs. The reefs had more sediment than I was expecting, but the diversity on the reefs was still greater than almost all reefs I have visited. The first species that I noticed were Gregonian sea fans, that were purple and rose gracefully from the mounds of coral.

Halimeda sp.

The sedimentation on the patch reefs made them a good habitat for green algae. The highest concentrations of green algae that I found were along the edge of the patch reef. There were multiple species of Halimeda, but I wasn’t able to identify the exact species. There was a lot of Caulerpa cupressoides, which was smaller than I was expecting but still very recognizable. I also saw a species that could be Anadyomene stellata, but I need to look at the morphology of the algae more closely.

Tomorrow I’m looking forward to having more time in the water and learning about more reef species.