Tag Archives: Urchins

26/05/19 Urchin Searchin’

We began the morning with a survey of sea urchins in patch reefs (in and out of marine-protected areas). We collected urchins in a bucket, then identified them by species and determined the diameters of their tests (in centimeters). We found long-spined urchins (Diadema antillarum) (don’t touch!), slate-pencil urchins (Eucidaris tribuloides), reef urchins (Echinometra viridis), and a few West Indian sea eggs (Tripneustes ventricosus). Although I was hesitant to jam my hand into small crevices in the coral to retrieve these spiny creatures, I had fun catching the urchins while simultaneously discovering how stubborn they can be. Some of those sea urchins were really wedged into their crevices and would not budge.

Bucket o’ urchins!

We collated our data into a poster, then transitioned into lectures on  crustaceans, hydrozoa, cubozoa, scyphozoa, ctenophores, and climate change and its effect on coral reefs.

We ended the night with a night snorkeling session from the dock to a patch reef nearby (which we got lost on the way to). It was a surreal experience. In the brief time that we were out in the water, I did not get to see much, but the creatures that I saw —including some tasty-looking lobsters—were vastly different from the ones that I normally see during the day. Our limited field of vision under water made for an invigorating experience, like when sting rays appeared and disappeared from darkness.

Day 11: Ooo the Drop-off…

Blog Post #11
Day 11: Ooo the Drop-off…

Written at 6:25 am on May 26th


We did a lot of exploring and learning, and even some of the drop-off (figured I throw in some Finding Nemo reference even though it’s the wrong area of the globe). We started the morning of May 25thwith a presentation from the Belize Fisheries and Coast Guard divisions and how they enforce their laws. It was awesome to get some context on just how important of an area Glover’s Reef is.


Then we hopped on the boat for a morning of exploring the forereef—we stopped at two different places: an area behind Southwest Cay and an area behind our island that is the drop off. These snorkels were really gorgeous; the diversity of coral, fish, and other wildlife such as rays, sponges, and soft corals. There seemed to be a lot of Ctenophores, which are commonly known as comb jellies even though they aren’t jellyfish. I had hoped to see a sea turtle since they love snacking on those, but alas, none were found.


The sponges in the spurs and grooves leaving to the drop-off weren’t very diverse in species but had incredible ranges of color. The branching tube sponges were gray to green to blue, and the rope sponges varied from brown to red to tan. There were a few vase sponges that had hints of pink and light blue and green in the same one!


Vase sponge with baby fish (hard to see)
branching tube sponge

In the afternoon, we collected sea urchins to measure their size and species richness to test the health of the reef at one reef patch inside the MPA and the other outside of it. I did manage to nab a black sea urchin with some tongs, after many tries. We haven’t yet analyzed our data, so stay tuned!


My lip is sunburned, but my soul is happy. I love being out on the water and exploring, and even better to be doing science at the same time!

Urchin Hair Don’t Care (Day 3)

Today was an incredibly full day. We put the quadrats we made last night to good use by first estimating crab density on the island, then taxons represented within the seagrass beds, and then finally advancing to quantifying reef health on a patch reef within the conservation zone. Tomorrow we are going to repeat the procedures for quantifying reef health within the general use zone to see if there are observable differences between the two zones.

Therese swimming along our transect.


Another way we are going to compare the two zones is by urchin size. Today on the patch within the MPA, 16 of us collected as many urchins as we could for 25 minutes. I saw Diadema urchins but I did not collect any because their spines are the longest and they seemed to be hidden deeper than the other two species. I only found one Slate Pencil Urchin but lots of Reef Urchins.

A Slate Pencil Urchin collected within the Marine Protected Area.

Today I encountered two weird issues. First we drifted away from our quadrat within the seagrass, and it took about 20 minutes of frantic searching before we found it again. The other issue happened during the urchin hunting because somehow I got four urchins stuck in my hair really badly. For a good while I thought we were going to have to cut them out but eventually they let go.

Adrienne pulling the urchins out of my hair.

Since we were doing the work with the quadrats today, I had less time to find green algae. I did see more Acetabularia calyculus and Rhipocephalus phoenix again. I also saw what I think was Caulerpa cepressoidea and maybe some Chaetomorpha.

Quadrats, Transects, and Urchins (Oh My!) 

DAY 3 — This morning I woke up to the sound of the ocean. Very pleasant. We started our second day at Middle Caye with some quadrat practice, investigating the crab density on the island. We worked out standards for the whole group to use with the transect tape (100ft) and intervals of quadrats (every 20ft) in order to ensure that our data, collected in six separate groups, would be comparable.

After our land practice, we left the turf and went to the surf for transect practice in the sea grass beds. We were looking at benthic organism diversity, and recorded any sightings of molluscs, crustaceans, algae, echinoderms, cnidarians, annalids, and arthropods in our quadrats. Alessi and I nailed it, and were able to efficiently collect data from the quadrats and spot some cool creatures along the way. We saw some really cool anemone, a conch, and a barracuda.

Quadrat on seagrass bed

After lunch, we embarked on the Koolie Gial, with Captain Buck. In the patch reef, we were looking to assess reef health and cover. Alessi and I were both thrilled to see so many representatives of our taxonomic groups, soft corals and sponges, respectively.

Speaking of sponges, I saw some good ones! First and foremost, the Chicken Liver Sponge (Chondrilla caribensis)! A very exciting spot for me.

Chondrilla caribensis up close 
Chicken Liver Sponge (Chondrilla caribensis)

I also saw rope sponge, probably the Scattered Pore Rope Sponge (Aplysina fulva). Another familiar face, the Branching Vase Sponge (Callyspongia vaginalis) was also on the patch reef today.

Aplysina fulva

Our final reef-related activity of the day was an urchin collection. For 25 minutes, we all swam around the shallow reefs and tried to grab the urchins hiding in little rock crevices. We brought a bucket of urchins back to the island and will measure them tomorrow morning before returning them to their home.

Day 4: Full Circle (05/19/2017)

I lie on my back on the hammock, swaying gently side-to-side in the breeze. My eyelids float down after a busy morning and afternoon. I witness deep oranges and rusty reds shifting, bursting, and intertwining on the backs of my eyelids, luminescent projections of the intense tropical sunlight. Needless to say, these entrancing visions were enough to lull me to sleep.

This morning I felt quite different – energized and adventurous. Soon after breakfast, my classmates and I measured the sizes of the urchins we caught yesterday at the Marine Protected Area (MPA). We then snorkeled at a non-MPA and carefully collected urchins there. Interestingly, the urchins tended to be larger and more numerous at the MPA. However, the non-MPA was home to the largest urchin we found, a long spine sea urchin (Diadema antillarum) that measured 5.8 cm in diameter.

With its mounds of different corals, the reef visited today was teeming with a plethora of diverse colorful creatures. Some notable sightings included a green sea urchin (Lytechinus variegatus), spiny brittle stars (Ophiocoma paucigranulata), and numerous ctenophores. The green sea urchin was about 4 inches in diameter and found on the seafloor. The spiny brittle stars, found under rubble, had central disks of about an inch in diameter and arms about 3 inches long. The brittle stars would try to move back under the rubble when exposed. None of the echinoderms were visibly interacting with other organisms. Today’s most spectacular sighting was a spotted trunkfish (Lactophyrus bicaudalis); its dynamic black and white speckles contrasted with the mellow blue backdrop of the ocean.

After spending the afternoon discussing my class’ data collected and observations noted, I was exhausted. We had an hour until dinner, so I lied on my back on the hammock.

Urchins are Prickly and Math is Hard (Day 4)

Today we completed our MPA vs. General Use Zone comparison by doing quadrat coral cover assessments and urchin collecting on a patch reef in the General Use Zone. It was a lot easier today because conditions were calmer. During the urchin collection, I finally saw Sailor’s Eye Algae! I couldn’t find it again when I went to take a picture, but they look like big shiny bubbles. I also was able to find good examples of calcium carbonate Halimeda chips within the sand.


Some sand grains of algal origin produced by this Halimeda algae.

Today we also listened to a presentation by Javier, our marine safety officer, about the history and culture of Belize. He told us that the four main ethic groups of Belize, the Mestizos, Creoles, Garifunas, and Mayans, were all represented within the staff on Middle Caye, which is only comprised of six people!

The first lowlight of today was that I realized that I am trash at arithmetic when synthesizing our data. The second lowlight was that I realized there had been a frog in my Cheerios box after a frog jumped out of my Cheerios box. Truthfully I hadn’t been getting hungry enough in between meals to be eating them much and they were kind of a jank flavor, but it grossed me out nonetheless.

Some of the urchin size data we were trying to make sense of. Math is hard.

Weather permitting, tomorrow we are going to go snorkel on the reef crest and maybe also do a night dive. I am really excited to see different reef scenery now, so I’m keeping my fingers crossed.

In Which Things Go As Planned

  Our first boat day was today! We measured live coral cover compared to macro algae and recently dead coral. We also collected sea urchins for 25 minutes and then measured them.

We actually did two boat trips today. One was to the south of the island in the marine protected area and the other was slightly further away in the same direction outside of the protected zone. We collected the same data at each site and we will compare it later when we analyze.

Pencil Urchin
Pencil Urchin

I saw a huge wall of queen conch at our second site, but all of them were dead. Apparently the huge eagle rays eat them. I also saw flamingo tongues on gorgonians. It’s satisfying when things behave like they’re supposed to.

After we got back from the boat trip I became the first 319 student to actually take a kayak out. I went down into the mangroves and explored a little with Ella and Stephanie. We saw the skeleton of a pelican hanging in a tree, an osprey, some crabs on logs, and a beautiful sunset.

Pelican skeleton
Pelican skeleton


After dinner we had free time, and we hung a light off the dock to see if we could attract anything to it. Mostly we got a bunch of tiny fish and some crustaceans (maybe shrimp?). People switched from looking at the light underwater to looking at the stars and some point. They were beautiful.

Searchin’ for Urchins

Today we continued with our quadrat theme to look at stony corals inside Glover’s Reef Atoll. For our first boating expedition, we ventured to a marine protected area (MPA) to study the health of coral reefs. Our day was entirely dedicated to data collection, but I still found a huge amount of herbivorous fish hiding among the corals. The dusky damselfish (Stegastes fuscus) is definitely the most common, but all three species of damselfish mentioned in my last blog are very easy to find on the patch reefs. I also found several ocean surgeonfish (Acanthurus bahianus). Like all surgeonfish, this species has a scalpel-like spine on their tail used for slashing predators that’s fairly easy to see in the water.

Initial phase stoplight parrotfish (Sparisoma viride).

I also managed to find a red and brown stoplight parrotfish (Sparisoma viride) in what is known as its initial phase. Parrotfish are unique in that they can change their sex; initial phase parrotfish are either females or primary males. However, the large, conspicuously colored parrotfish are actually supermales, or females that later became males. Guess even fish can be transgender.

West Indian sea egg (urchin).

We also spent a good portion of the day collecting sea urchins to assess reef health. You can find urchins in all the nooks and crannies of a reef, but it turns out getting them out is the hard part. We managed to collect a fair number (sustaining only minor injuries) before measuring them and sorting them by species.

Each day on the reef, we learn about a different taxonomic group, adding them to our arsenal. It’s incredible how each presentation adds yet another dimension to my next visit to the reef. Two days ago, I wouldn’t have been able to tell you what Acropora cervicornis was, but now I’m able to spot it (both alive and dead) out on the reef.

And finally, we ended it all by laying on the dock under the stars. The ocean and sky merge together here, forming an infinite black canvas littered with pinpricks of light. Forgive me for the romance, but I might’ve even seen a shooting star. Isn’t it pretty to think so?