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Research? More like reef-search!!! (Day 4)

Hi all, it’s Faith with Day 4 updates from the 2022 Belize trip!!!

Today we started our attempt to answer our new research questions: “ What is the correlation between percent live coral and the sea urchin population?” and “How does that correlation change between mpa and non mpa reefs?”

Our hypothesis are as follows:  we think that areas with moderate amounts of sea urchins will have the highest percentage of live reefs. Additionally, we think that the unprotected reefs  will have an abundance of sea urchins and therefore have less live coral. We think this because unprotected reefs are susceptible to overfishing, which reduces the amount of creatures that prey on sea urchins.

Our methods were to lay out 50ft of transect tape in random, radial direction s from one central point. Then, at every 5 meters we would count the squares of live coral and dead coral using a quadrat. Our final part, would be collecting as many sea urchins as possible in 10 minutes, which we would identify later.

This method sounds easy in practice, but let me tell you. Counting. The. Corals. Was. Hellish. Don’t try to tell me,  “Corals are delicate, don’t touch them because they’ll get hurt.” * I now know the truth. They will cut you, burn you, and make you lose your quadrat to the current. If I wasn’t wearing a wetsuit, I would be covered in the wrath of a fire coral right now. So, yeah, getting the data from the West patch reef was very difficult, but collecting the sea urchins wasn’t easy either. Most of the time, the sea urchins were 1cm-2inches burrowed in the remains of hard corals (specifically the ones with a little algae overgrowth). They were hard to see at first, but after awhile they were easy to find. I saw many types, and as the echinoderms expert, I knew exactly what they were (mostly). The most common find was a Common reef urchin, Echinometra viridis, identifiable by the dark body, orange spikes, and small white rings on their spines. We saw a few reef burrowing urchins, Echinometra lucunter, and 2 pencil slate urchins, Eucidaris tribuloides. We found so many urchins that I could hardly count the ones in the wild, but we brought back 20 to classify.  My three favorite finds of this trip were a Flamingo tongue snail, a lobster trio(featured picture), and the donkey dung sea cucumber (Holothuria mexicana). I found the sea cucumber under a coral, and I got to hold him, he was very squishy and started molding to the shape of my hands. I couldn’t identify any particular behavior that he was doing, but maybe he just needed a nap.

Our other daily activity was making a taxa showcase! We gathered lots of creatures from the seagrass beds behind the kitchen. We found one Spiny Sea Urchin, Diadema antillarum, and Kaiu graciously scooped it up for me to talk about. He hardly stole the show though because we found so many types of green algae, a lobster, and two mantis shrimp!

Oh, and did I mention that Prof. Solomon speared a lionfish? Looks like we might have ceviche tomorrow!

Till then!

QOTD: “You made the *dumb* graph, this is on you

The first mantis shrimp I’ve ever seen. Everytime I go to an aquarium they don’t have them, and they are supposed to be really hard to find. I finally accomplished my life goal (twice in one day!!!)
Me and the Donkey Dung Sea Cucumber, Holothuria mexicana
Black long-spined sea urchin, Diadema antillarum, somehow being carried in a tiny net
Some of the guides we used to identify the sea urchins. I made the one on the left!!!
My teacher speared a lionfish in front of me … I LOVE BIOLOGY

* please do not intentionally touch corals its a) illegal and b) bad for corals

24/05/19 Piscivorous fish are more metal than herbivorous fish. Periodt.

We took the boat out for the first time to survey two patch reefs. The first one, Marisol, was within a marine-protected area (MPA). The second was not within a marine-protected area (non-MPA). There were some grey clouds in the sky as we drove out to the first patch reef, but I did not feel the sprinkling as I was snorkeling in the cold water. I saw snappers as usual, and what I thought to be a foot-long grouper that quickly swam away before I could fully process its presence.

In the afternoon, the class geared up to wade into sea-grass off of the island. We were looking for creatures to capture and keep in a ‘touch tank’ briefly for our observation. As a class, we caught many queen conchs (and one conch shell occupied by a crab), two donkey-dung sea cucumbers, a sea egg urchin, a pencil slate urchin, a red heart urchin, an octopus!, two fire worms, a damselfish, several brittle stars, two sun anemones, several types of coral and algae, and many hermit crabs—no piscivorous fish though! The water is too shallow for these big boys. It was interesting to feel and observe the organisms from other taxons though. The donkey dung sea cucumber was particularly interesting as it molded into your hand as you squeezed it.

Me touching a West Indian Sea Egg (Tripneustes ventricosus), a type of urchin

We ended the night with lectures on herbivorous fish, piscivorous fish (given by yours truly), and how competition, predation, and environment shape coral reefs.

Day 12: Sea Cucumbers Make Great Water Guns

This morning, we started the day off right with plates of fat banana and pineapple pancakes. I’m beginning to think that my life is actually a dream, at least for the time being.

We spent the morning analyzing data we collected in the previous two days about live hard corals and sea urchins. We used coral cover and sea urchin diversity and size as measures of overall reef health, and we wanted to see whether the Marine Protected Areas implemented by the Belizean government are actually improving reef health. After analyzing our data, we decided that we couldn’t solidly conclude anything about the effectiveness of MPAs. We’d have to conduct further studies before we can make a real statement about MPAs.

After lunch came the exciting part. We waded out to the shallow reefs behind the island to look for critters in the sea grass and coral rubble! When we first waded out to sea, the ground was nothing but a sludge of mud and rotting seaweed. It was, like, reaaaal nasty. The water was so hot, too! Like a bathtub, except crusted with algae and stinking of fish.

Once we’d waded out a little, the water became much cooler and clearer. It became deep enough to swim and search for critters in the sea grass. My first find of the day was a donkey dung sea cucmber (yes, that’s its real name!) that was about 35 cm long. It literally looks like a gigantic, brown donkey turd, except it has tube feet and a red belly. I dumped that guy into our sea collection bucket that we later took back to the island to examine.It was a fun afternoon filled with much turning over of rocks and investigating the benthos for crustaceans, brittle stars, and fish.

Today was another great day for Echinoderms. I found that many brittle stars, especially spiny ophiocomas, love to hide under algae-encrusted pieces of coral rock. Once I lifted up the rubble, I’d often see one or two spiny brown and white-banded arms disappearing around the bend.

Spiny ophiocoma brittle star.

I snatched 5 to put in our collection bucket before they disappeared. Two were quite large, maybe 10 cm from arm tip to tip, but one was teensy! It was 2 cm from tip to tip. Ceyda also found a smaller donkey dung sea cucumber lounging in the sea grass, and Elena found a slate pencil urchin to add to my collection.

Fun fact: sea cucumbers make great water guns! When submerged, they fill themselves up with water. You can pick them up and gently squeeze to make them shoot the water out at anyone who crosses your path! Scott used one of the donkey dung cucumbers to squirt me with water, so naturally, I had to get him back. Again, clearly, this was all in the name of science.

Here I am holding the larger of the donkey dung sea cucumbers that we found. 

Other cool spots and catches of the day included a large nurse shark, a gigantic spiny lobster (and 3 smaller ones), a cocoa damsel fish, and a baby Caribbean reef octopus!! We spotted the nurse shark swimming in the shallows near the reef crest, and I scooped up the bright yellow damsel fish in the old conch shell that it lived in. Bonus: that same conch shell also turned out to be home to the octopus, which was a super cool find!

Everyone’s favorite was the octopus, which Jessica christened Herbert. He was small enough to fit in the palm of a hand and changed colors very frequently. I think we stressed him out though, because he inked in the tray we held him in 🙁

Herbert the Caribbean reef octopus.

I was shocked by the sheer diversity and amount of animals we could find here just by wading out behind the island. It’s truly incredible – I didn’t even begin to detail all of the organisms we found today. If I did, I’d be writing for 20 pages.

I can’t believe that we only have two more full days in this idyllic place. I don’t want to think about leaving, but for now, I’m going to enjoy learning about this ecosystem to the fullest!