Do Groupers Change Color

Carole Stephens
• Monday, 07 December, 2020
• 13 min read

Common Name grouper Kingdom Animalia Phylum Chordata Class Osteichthyes Order Performed Family Serranidae Genus Species Epimetheus SPP. Diet Other fishes, squids, and crustaceans Incubation Oviparous (egg laying) Sexual Maturity No data Life Span Relatively long-lived; some groupers have lived at SeaWorld, San Diego for more than 30 years Range Varies by species Habitat Varies by species Population GLOBAL No data Status IUCN: Several species listed as Vulnerable or Threatened CITES: Not listed Uses: Not listed Some fish in this family can grow to incredible sizes, such as the Jewish (Epimetheus Tamara) of the tropical Atlantic Ocean and the Queensland grouper (E. lanceolatus) of Australia.

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Some groupers are so huge that when they open their mouths to feed, they create a suction that is powerful enough to inhale small prey. In addition to their possible great size, another defense that some groupers have is the ability to change the color of their skin.

The Caribbean Coney (Cephalopods vulva) demonstrates a more advanced color shift. If disturbed, the Caribbean Coney will try to hide in a coral crevice, which normally has a white, sandy bottom.

To blend in with this environment, this fish alters its color so that its lower body fades to white and its spots contract to tiny pinpoints. Other groupers have developed color patterns composed of stripes, spots, or blotches that help them to blend in with the bottom of coral reef areas.

All young yellow mouth groupers (Mycteroperca interstitial is) are born females, but as they grow larger they change into males. Only small percentages survive long enough to become a male, thus ensuring the greater majority are egg-laying females.

Even more surprising, some in the genus Serra nus are rare examples of fishes that can be male and female at the same time. In the United States, Jewish and Nassau groupers (E. stratus) are protected from all harvesting.

grouper painting paintings delilah oil daily colors
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Anyway, he started swimming away almost immediately, turned white with large black stripes vertically right before my eyes. My dive buddy, although close, didn't see what I was seeing and without a slate to explain my surprise, she wouldn't have known anyway.

Well, as I watched this grouper swims a little way ahead settle down into another little niche, it turned completely white with black spots. # of Dives: 500 – 999 Location: Silicon Valley, CA / New Bedford, MA / Kira, Maui Many fish change colors for things like mating, fighting/aggressive/territorial warning, hunting, particularly doing cooperative hunting with another species.

One becomes the male and turns a lovely blue colour, and he has a harem of chicks. # of Dives: 50 – 99 Location: Norfolk, VA That sounds pretty interesting.

# of Dives: 200 – 499 Location: Raymond, NH In the above pictures he changed back to white after I swam by. One time while snorkeling off Moore, I saw a group of Trumpet Fish.

# of Dives: 2,500 – 4,999 Location: Santa Catalina Island, CA Yep, I've observed the same color changes in groupers in the Caribbean and Florida. # of Dives: 200 – 499 Location: Makarios, HI I believe I saw my grouper around Tori's Reef.

osteichthyes grouper giant chondrichthyes between difference juvenile epinephelus wikipedia lanceolatus groupers river monsters young fish freshwater kampachi hawaii massive class
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I thought I was nuts but when I saw it turn back to flat, dark black I knew I wasn't going crazy. Nice pics Cecil, I wish I would have had the good fortune to get the many changes on a vid or something.

Photo © Anne DuPontThese large, oblong fish can change both color and gender, and live at the rocky reef bottom of tropical Western Atlantic waters. They grow up to 4 feet long and eat mostly crustaceans and other smaller fish by opening their mouths and inhaling them.

The flesh is primarily marketed as fresh, however there have been reports of ciguatera poisoning from human consumption of this fish. Ciguatera poisoning is caused by dinoflagellates (micro algae) found on dead corals or macro algae.

By feeding on these corals and macro algae, herbivorous fishes accumulate a toxin generated by these dinoflagellates. If accumulated levels of the toxin are great enough they can cause poisoning in humans whom consume the flesh of these fishes.

Poisoned people report having gastrointestinal problems for up to several days, and a general weakness in their arms and legs. The Nassau Grouper is currently assessed as “Endangered” by the World Conservation Union (IUCN).

grouper panther fish altivelis polkadot thatpetplace betta marine medium groupers pinit non type
(Source: reefs.com)

The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species. Occurs in the Gulf of Mexico in limited locations including the Yucatán, Tortuga's, and Key West.

This grouper is common on offshore rocky bottoms and coral reefs throughout the Caribbean region. They occur at a depth range extending to at least 295 feet (90 m), preferring to rest near or close to the bottom.

Juveniles are found closer to shore in seagrass beds that offer a suitable nursery habitat. At these stations, cleaner wrasses pick parasites and dead tissues from the grouper’s gills and body.

There are five irregular dark brown vertical bars on each side and a large black saddle on the top of the caudal peduncle. The Nassau grouper can change color pattern from light to dark brown very quickly, depending upon the surrounding environment and mood of the fish.

The smaller individual displays a bi colored pattern, with a dark head and white fins, caudal peduncle, and ventral body. These teeth are not used to tear flesh as with the barracudas and sharks, but rather to prevent small fish from escaping.

grouper nassau fish chuck risk knapp aquarium shedd credit
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Size, Age, and Growth Growing to a maximum of 4 feet (1.2 m) and weighing over 50 pounds (22.7 kg), this grouper is one of the largest fish on the reef. Food Habits As a carnivorous predator, the Nassau grouper has a diet that consists mainly of fish, shrimps, crabs, lobsters, and octopuses.

Prey fish include parrot fishes, wrasses, damsel fishes, squirrel fishes, snappers, and grunts. This clever fish patiently waits in hiding, utilizing its ability to camouflage, until it pounces on its prey.

By opening its mouth and dilating the gill covers to draw water in, groupers generally engulf their prey hole in one quick motion. Reproduction The Nassau grouper forms large spawning aggregations from a few dozen to over 100,000 individuals.

These aggregations form in depth of 65-130 ft (20-40 m) on the outer shelf near the full moon during the winter months. Release of gametes is initiated by the female moving in a rapid forward and upward direction.

It is difficult to distinguish different species of grouper larvae from one another, since what information is known about egg and larval development is general. The eggs hatch into pelagic larvae that drift along with the currents for a month or so, prior to becoming juveniles.

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Juveniles settle at lengths of approximately 32 mm, residing in vegetated areas near coral clumps. At 120-150 mm in length, the juvenile Nassau groupers move out from vegetated areas to surrounding patch reefs.

These nematodes can have negative impact on the numbers of eggs produced by female Nassau groupers. At these stations, bodies and shrimps remove isopods from the bodies, fins, mouths, and gills of these groupers and other fish.

The genus name comes from the Greek Epimetheus meaning clouded over while stratus is Latin, referring to the striped color pattern. Synonyms include Antics China Bloch and Schneider 1801, Sparks chrysomelas Labeled 1802, and Serra nus gymnopareius Valentines 1828.

The Peacock Hind is a large, deep bodied fish, covered with small, bright, blue spots edged in black. Peacock Hinds have small eyes that are mounted near the top of the head, which is typical for editorial fish.

They can reach 17” (44 cm) and groupers are known to live from 9 to 37 in the wild, possibly longer in captivity with proper care. Peacock Hinds were introduced in the 1950s to the Hawaiian Islands as a possible food source, although today, most carry ciguatera poisoning (causes neurological disease) and they are off the menu in this area.

painting grouper paintings delilah daily oil demo
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The Cephalopods genus, commonly referred to as “Hinds,” contain smaller species of groupers which are more appropriate for home aquariums. They range in size from around 9” to 22.5,” and at least 8 of these species range from 9 to 11.8.” The Peacock Hind, sometimes referred to as the Blue spotted Grouper, can be confused with the Blue spotted Hind, mainly due to the fact that both have bright blue spots.

Upon closer examination, the Peacock Hind has a wide, bright, blue edging on the fins. The coolest behavior observed by the Peacock Hind is how it will follow octopuses and Gray Morays who are foraging for food.

If one of them flushes out a prey fish, the Peacock Hind will get a free dinner! Peacock Hinds will also hide within large schools of Parrot fish which enables them to get very close to their pray without being seen.

The second challenge would be filtration, since groupers are big eaters, and produce copious amounts of waste, requiring a good quality oversized skimmer and two canister filters like Exam or Fluvial, cleaned twice as often as the directions suggest keeping them working effectively. A slender fish and even eels that are the same length as your Peacock Hind will be consumed.

At times, they will try to eat a fish they can’t quite get down their throat, and the aquarium will have to lend a hand to extract the unfortunate tank mate. Other tank mates are safest if they are deep bodied and of similar size or larger.

grouper painting delilah paintings daily
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If attempting to keep with cleaner shrimp from the Lyman or Steno pus genus, add them first. Peacock Hinds need to be the last fish added to an aggressive community tank.

This video helps to demonstrate the enormity of the Peacock Hinds, as you watch an Emperor Angelfish swim by in the background! They are covered from nose to tail fin in bright blue spots that are edged in black, except the area of the chest in front of the pectoral fins, which is spotless.

This is an excellent example of how tiny juvenile Peacock Hinds, or Blue Spot Groupers can be! Add as the last member of an aggressive community reef or fish only tank and provide places for them to hide.

Other creatures they have been known to consume, according to the region are Dusky Tangs (Acanthus nigrofuscus), Convict Tangs (A. Triostegus), Purple Tangs (Nebraska Tantrum), Sail fin Tangs (Z. Desjardinii), Orange Bristle tooth Tangs (Ctenochaetus stratus), Iridescent Cardinal Fish (Aragon kallopterus), Orange Lined Trigger fish (Baristas undulates), Red Speckled Pennies (Cirripectes various), Arc Eye Hawkish (Paracirrhites arcades), Six-line Wrasses (Pseudocheilinus hexataenia), Pterocaesio Tile fish, Hawaiian Squirrel fish (Sargocentron xantherythrus), Belted Wrasses (Stethojulis Alberta), Lyre tail Antics (Pseudanthias squamipinnis), Plunger’s Wrasse (Thalassemia klunzingeri), Sweepers, Blue Green Chromes (Chromes irides), Pseudogrammas, Mackerels, Gobi es, Gray Morays (Sidereal rise), Dam selfish, crabs, decayed shrimp, mantis shrimp, and spiny lobsters. Those long prey fish/eels will coil up in the stomach of the Peacock Hind until digested.

As adults, Peacock Hinds are found alone, or in harems that consist of one male with as many as six females. They will first perform lateral displays and open their huge mouths to intimidate their opponent.

nassau grouper groupers season during mate spawn moon every november march mating southern
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If a rival grouper wants to fight, both fish will face each other and lock jaws for up to 5 minutes! The loser, typically the weaker fish, will then swim off, leaving the harem of females for the victor.

Some websites suggest the tank needs to be 250 gallons, and this is not out of the question, especially if you are considering more than one grouper, since these large fish produce a lot of waste and higher water volume will help keep up the water quality. The tank should have a heavy duty skimmer due to the large amount of waste this fish produces.

Feeding groupers fresh water fish will cause health issues if continued for too long. Do not house them with other Peacock Hinds, although they will be fine with other groupers as long as the tank is large enough.

Some websites suggest the tank needs to be 250 gallons, and this is not out of the question, since these large fish produce a lot of waste and higher water volume will help keep up the water quality. The tank should have a heavy duty skimmer due to the large amount of waste this fish produces.

Feeding groupers fresh water fish will cause health issues if continued for too long. Do not house them with other Peacock Hinds, although they will be fine with other groupers as long as the tank is large enough.

fish geico giant commercial fisherman grouper bodinsterba
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Once they are eating, quickly switch over to prepared foods such as freeze-dried or frozen krill, mys id shrimp and pellets for carnivores. Also offer a varied diet of raw crustacean and fish flesh which can be obtained from the grocery store.

Groupers are hardy and fairly easy to keep, although they do need good filtration. Large Tanks 100 gallons and over, once water is aged and stable can be changed 20% to 30% every 6 weeks depending on bio load.

Large Tanks 100 gallons and over, once water is aged and stable can be changed 10% bi-weekly to 20% monthly, depending on bio load. In a 180 gallon tank (681 liters), arrange live rock, forming several places for the Peacock Hind to hide, especially if the fish is a juvenile.

Each grouper in the tank will need 2 places to hide to help tone down aggression. They may be induced to spawn indoors if they are conditioned with more feedings, then the temperature is raised 2F, and there is a longer daylight period.

Peacock Hinds, although found in harems in the wild, are best kept singly in a captive environment. In very large 500 to 1000 gallon systems, outside saltwater ponds or public aquariums, a few females can be kept with a male.

grouper different clipart mounts sailfish king
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Also, arrange the live rock to provide barriers where their vision of each other is blocked from their normal hangout. Keep Peacock Hinds with fish of similar size if they are not as deep bodied, such as tangs and trigger fish who should be at least 13” long and fish who are deep bodied like butterfly fish and angelfish who are at least 7” long.

The only time the Peacock Hind becomes a threat, is if it is full-grown and these other fish are not, and they fit in their mouth! Figure out what kind of water quality you can maintain and only buy corals that are not picky.

Peacock Hinds have a much larger territory than many other groupers, which on average, is over 16,000 square feet! Males will spawn with each of the four or five females in the same night, with both releasing their gametes into the water column.

A culture was done on wild-caught groupers and there were 11 to 16 different species of parasites found on their bodies, including nematodes and cryptocaryon. The most easily cured parasite is Crypt (salt water ICH), but they are all treatable if caught in a timely manner.

ONEMA is often contracted when the aquarium doesn’t lower their salinity to the proper level of 1.009. The ONEMA parasite thrives in mid-level brackish water salinity, which is a specific gravity of around 1.013 to 1.020.

painting oil paintings grouper delilah daily
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Quick Cure and other 37% Formalin products will work perfectly well in both salinity ranges, but the lower 1.009 will help with the oxygen level. Anything you add to your tank from another system that has not been properly cleaned or quarantined, including live rock, corals, equipment and fish can introduce diseases.

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1 en.wikipedia.org - https://en.wikipedia.org/wiki/Atlantic_goliath_grouper
2 www.floridamuseum.ufl.edu - https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/epinephelus-itajara/
3 myfwc.com - https://myfwc.com/fishing/saltwater/recreational/goliath/