Grand Cayman Island: Sergeant major nest at Devil’s Grotto July 21 2022

Towards the end of the dive I was hanging out under the boat and started watching a Sergent major fish. They are common throughout the Caribbean and I have seen hundreds (maybe thousands) of them over the years. But it’s still interesting to observe their behavior, especially when it comes to their nesting.

Wikipedia says, “The sergeant majors is an oviparous species in which the males create nests where the females to lay their egg masses on rocks, reef outcrops, shipwrecks, and pilings.^[5] The males actively chase the females in courtship before the female releases approximately 200,000 ref, ovoid eggs which are attached to the substrate by a filament”

Reefnews.com does a good job explaining what happens next,

After building this nest, the male Sergeant Major will stay near the nest for several days to guard the eggs until they hatch. The female will leave during this time. The male will chase away all other fishes to keep the eggs from being eaten. The male Sergeant Major can be very aggressive during this time, and will even attack people in the water if they accidentally get too close to the nest. Although the Sergeant Major probably couldn’t hurt anyone, it will fearlessly try to drive away anybody that it thinks is too close to its nest.

http://www.reefnews.com/reefnews/photos/sgtmjr02.html

Grand Cayman Island: Tarpon at Devil’s Grotto July 21, 2022

Another thing that I like about Devil’s Grotto are the tarpons that usually hang out on the reef.

I have seen many tarpon over they years and enjoy diving with them. The Florida Museum website tells us, “tarpon can also tolerate oxygen-poor environments due to a modified air bladder that allows them to inhale atmospheric oxygen.” They go on to explain,

This swim bladder contains spongy alveolar tissue and has a duct leading to the esophagus that the tarpon may fill directly with air gulped from the surface. This feature allows the tarpon to take oxygen directly from the atmosphere and increases its tolerance of oxygen-poor waters. In fact, studies have shown that tarpon must have access to atmospheric oxygen in order to survive, and that juvenile tarpon are obligatory air-breathers. Adults living in oxygen-rich waters still roll and gulp air, probably as an imitative pattern based on visual perception of other tarpon.

https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/megalops-atlanticus/

I was able to slowly swim into a small school of them during the Devil’s Grotto dive.

I must admit that I would like to catch some with a rod and reel at some point.

Grand Cayman Island: Hawksbill Sea Turtle at Devil’s Grotto July 21 2022

My last dive of the trip was to Devil’s Grotto. I had some great dives at this site back in 2019 so I was excited to be here. Unfortunately, the Silver-side minnows that I got to see back in 2019 at this site were not here this time. But I did have several great sightings and encounters. One of them was a Hawksbill Sea Turtle. I spotted it at the surface getting some air and was able to intercept it on the way down.

The NOAA Fisheries website tells us, “Hawksbill turtles are omnivorous (feeding on both plants and other animals), but their preferred food in many areas is sea sponges. They will also eat marine algae, corals, mollusks, tunicates, crustaceans, sea urchins, small fish, and jellyfish.”

I was able to extract a few still images from the video footage.

Grand Cayman Island: Sharks at Royal Palms Ledges July 20, 2022

I only spotted one small Nurse Shark during my 2019 trip to Grand Cayman island. So I was thrilled to have three Nurse Shark sightings during the dive at Royal Palms Ledges during the 2022 trip. Royal Palms Ledges is off of Seven Mile Beach in the area of the Royal Palms Beach front.

The first encounter was the best one since the shark got close enough for some good video footage. Unfortunately, my GoPro decided to flip from landscape view to portrait view and I did not realize in until it was too late. Needless to say, I was disappointed when I watched the video file. But I eventually figured out how to edit the video in Adobe Premiere Pro and flip the video back to landscape orientation.

I truly think this shark spotted me and swam over to check me out. It was fine with me since closer is better when it comes to underwater video footage.

During the second encounter, the Nurse Shark was swimming down the sand channel. I turned to look at the dive guide then looked back and then shark was gone. It turns out the shark had dropped down behind some coral and was hidden from me. I swam up the channel a few kicks and spotted it.

The third encounter was towards the end of the dive. A few other people in the group spotted the shark first and got my attention. I could not get so close for this one but it was a treat to watch it swim by.

Grand Cayman Island: Reef Squid at the Crevasse Dive Site July 19 2022

One of the dive sites that we visited on July 19th is named the Crevasse. It’s one of the sites that is south of the George Town Cruise Port and Sunset House.

I saw all of the usual tropical fish, but the big thrill was getting some close up video footage of a couple of reef squid.

The marinebio.org website tells us,

These animals are social creatures often found in small groups that communicate through a variety of complex signals. Both cuttlefish and squid communicate by controlling the pigment in their skin. Messages such as readiness to mate, sexual identification, and alarm are flashed through various colorful spots, blotches, and background color. To signal slight alarm, their brow ridges turn bright gold and their central arms turn white. Their entire body will pale when a squid retreats from a potential predator and in open water when faced with an extremely aggressive predator, reef squid can also hide themselves and confuse predators by ejecting a cloud of black ink. Retreating squid near the protection of the reef will often turn dark brown or reddish in color to match their surroundings.

https://www.marinebio.org/species/reef-squid/sepioteuthis-sepioidea/

I was also able to extract a few images from the video footage.

Grand Cayman Island: Diving on the wreck of the Oro Verde July 18, 2022

On Monday, July 18th I was on the wreck of the Oro Verde (which means green gold in English). During the dive a Porcupinefish swam over to check me out. I always enjoy watching these fish. The Florida Museum website tells us, “The spines all over its body are modified scales, and when it’s threatened, it intakes water, puffing up and making the spikes stand out.” The site also mentions, “They secrete a toxic skin substance so are usually considered poisonous, although they have been known to be eaten in Hawaii and Tahiti.”

The wreck has an interesting story behind it. Back in 1976 the Oro Verde was shipping bananas (a type of green gold). Local lore says the captain wanted to make one last trip to retire so he also had a large shipment of weed (the other type of green gold) on board. Well, the crew confronted the captain to get a share of the profits, took over the ship then accidentally got it stuck on the reef. The cops seized the ship then burned the weed to destroy it. The story says the wind changed direction and blew the smoke into Georgetown and everyone was stoned for a few days.

The Scuba Diver Life website explains

The ship sat on the reef until 1980, when the local dive community adopted the wreck. It was moved into shallower water and purpose-sunk, now functioning as an artificial reef in 60 feet (18 m) off Seven Mile Beach. Divers can reach the wreck via a long swim from shore, but it’s more relaxing as a shallow second boat dive. It’s also a good spot for a night dive, with the scattered wreckage providing shelter for octopus, lobster and eels.

https://scubadiverlife.com/dive-site-oro-verde-grand-cayman/

The site goes on to explain, “Various hurricanes and storms have dispersed the wreckage over the years, so there are two moorings and a wide area to explore. Engines, pistons and other ship parts lay about.”

Honeycomb Cowfish in Cozumel July 20 2021

The afternoon dive on July 20th was relaxing. There was very little current and we were at a shallow dive site. This meant we could go slower and spend more time looking at sea life.

I was fortunate enough to encounter a Honeycomb Cowfish near one of the coral formations. I have always liked this fish because of the unusual body shape and their honeycomb color pattern.

The website mexican-fish.com tells us,

The Honeycomb Cowfish, Acanthostracion polygonius, is a member of the Boxfish or Ostraciidae Family, that is also known as the Cowfish and the Trunkfish and in Mexico as torito hexagonal. Their common name stems from the honeycomb like pattern and “horns” with sloped face and pronounced forehead.

https://mexican-fish.com/honeycomb-cowfish/

The article taught me that their, “deep triangular shaped body that is enclosed is a “carapace” made up of hexagonally-shaped plates fused together to form a shell or true carapace.”

The Florida Museum Website has more detail about the carapace. They describe it as, “consisting of thickened hexagonal scale plates that are firmly attached to each other with the exception of the cheeks to allow for respiration movements. There are openings in the carapace for the mouth, eyes, gills, fins, and the flexible caudal peduncle.”

Towards the end of the article they say, “Larger fish are potential predators of the honeycomb cowfish, however it may be undesirable as a prey item due to its protective external armor, the carapace.”

Whitespotted Filefish in Cozumel on July 19 2021

During one of the dives on July 19th I encountered a pair of Whitespotted Filefish.

A page from the Dive Paradise website tells us, “They have scales, although very small, and feel like sandpaper – not dissimilar to a shark’s skin. This roughness is how the Filefish got its name. Reportedly their dried skin was once used to finish wooden boats.”

They go on to say,

Every Filefish has a sharp spine on its head just above its eyes. It erects the spine when threatened as a defensive move. Its primary defense is to erect its dorsal and pectoral fins plus the spine to make it difficult for a predator to eat or to extract from its hiding place if back in a little cave.

https://diveparadise.com/2017/11/05/american-whitespotted-filefish-cozumel-reefs/

It looks like I made the darker filefish nervous since it’s spine was up as it approached me, and what I assume is it’s mate. Since both sexes can change color, that’s not a good way to tell which is the male and which is the female. The website says, “It is difficult to differentiate between males and females. The male fish are said to have slightly larger appendages extending from their bodies at the base of their tails.”

When the orange colored filefish turned it’s tale towards me I can see what I think are the “appendages extending from their bodies at the base of their tails.” Although it’s still difficult to tell for sure, this would make the orange colored filefish the male.

Foureye Butterflyfish in Cozumel, July 19, 2021

A tropical fish that I enjoy watching is the Foureye Butterflyfish since they are often in pairs. The Florida Museum website tells us, “This is one of the few fish that seems to mate for life.”

The website continues to say,

Male and female foureye butterflies form pairs early in life. These pairs can be long lasting, suggesting that a monogamous relationship may exist between the pair members. If the two fish get separated, one partner will swim upward for a better view in an effort to rejoin the other partner. Courtship between the two is prolonged and energetic. Often the fish will circle each other, head to tail, until one fish breaks and runs, with the other close behind. They will chase each other all about the reef, and chase away any lone foureye that approaches them. Actual spawning takes place at dusk. The female releases from 3000 to 4000 eggs a night. The eggs are small, pelagic, and hatch within a day.

https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/chaetodon-capistratus/

Although the fish are beautiful, take a look at how healthy the coral is that they are swimming near! After seeing so many diseased and dead coral in Florida, healthy coral is a welcomed sight. Although coral identification can be a challenge for me, based on the star coral identification page on the scubadiverslife.com website, I think we are seeing Mountainous Star Coral and Lettuce Coral.

Queen Triggerfish in Cozumel, Mexico on July 21, 2021

It took me most of the week to get a good video of a Queen Triggerfish. Notice how it changes color as it swims by. Since many of my favorite fish can change color, I became interested in learning how it happens.

The New World Encyclopedia tells us,

Chromatophore is a pigment-containing and light-reflecting cell, found in various invertebrate and cold-blooded vertebrate animals, that can help bring about changes in color or brightness in the organism. Among animals with such cells are various crustaceans, cephalopods, amphibians, fish, and reptiles. Through aggregation or dispersion of the pigment and reorientation of reflective plates in single cells (in most animals) or through the muscular movement of complex chromatophore organs (in cephalopods), the color or brightness of the entire organism or part of the organism can change, which is useful for camouflage, signaling, temperature regulation, and protection from radiation.

https://www.newworldencyclopedia.org/entry/Chromatophore

It looks like this Queen Triggerfish was changing color to blend with the surroundings for camouflage.