Tag Archives: parrotfish

Herbivorous Fish Everywhere!

May 24th, 2019


Today we embarked on a lengthier project, measuring percent live coral cover in marine protected area reefs vs. reefs outside of them. After breakfast and a boat safety talk, we climbed into a whaler and travelled to our protected area reef. The weather was perfect for snorkeling, barely any wind and cloudy due to approaching rain.

Jumping into the water and swimming to the sandy center of the reef (where our groups met up), I already saw so many colorful corals with different little wrasses darting amongst them. I reeled out my groups transect line, swimming though different sea fans (a soft coral) and over top of the coral heads (careful to avoid the stinging fire coral). Swimming over the corals was just an amazing and surreal experience, seeing all the different colors in the crystal clear was breathtaking. After finishing our quadrats, we got a chance to swim around the reef and explore.


The reef was full of herbivorous fish. There were Blue Tang Surgeonfish, what species Dory is from Finding Nemo with their characteristic blue bodies and yellow caudal spines, munching on some algae that was in the coral. There were also a lot parrotfish swimming in and under the coral heads. A very prevalent species was the colorful Stoplight Parrotfish. Parrotfish are special in that they have two “phases” of coloring and can be hermaphroditic (can change sexes). The initial phase of the stoplight parrotfish has a red orange underbelly and speckled body scale. There were also terminal phase Stoplight Parrotfish, which have a green head and body with yellow scales at the base of the tail and have orange/red scales on their tail. They also have a pink strip near their pectoral fin. In both phases, Stoplight Parrotfish are quite spectacular, and often feed in groups so they are easy to see. I also saw more Ocean Surgeonfish and Three-spotted damselfish. I also saw an adult Dusky Damselfish swimming through the coral, with its brown/black coloration and its rounded, continuous dorsal fin.

A Stoplight Parrotfish
Stoplight Parrotfish (initial coloring)

After around fifteen minutes of swimming, we loaded onto the boat and went to the unprotected reef and performed the same task. Per usual, we ended the day with lectures.




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?