Gag Grouper - Profile | Traits | Facts | Breeding

The gag grouper, scientific name Mycteroperca microlepis, the gag, velvet rockfish, or charcoal stomach, is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is a part of the family Serranidae, which additionally contains the anthias and sea basses.

Gag grouper Profile

Gag grouper grows slowly, can attain more than 3 feet in size, and weigh as much as 50 pounds.

Gag grouper can live as long as 30 years.

Gag grouper is protogynous hermaphrodites – they start life as females and sexually mature around age 4. As they get older, they modify to males, around age 8.

They spawn from mid-January to early May within the South Atlantic and from late January to mid-April within the Gulf of Mexico. Gag spawn in massive teams alongside the continental shelf. Females spawn a number of instances per season, releasing between 60,000 and 1.7 million eggs every time they spawn.

Gag grouper eats quite a lot of fish, crabs, shrimp, and squid.

Adult gag grouper and enormous fish prey on the juvenile gag.

Sharks and different massive fish prey on the adult gag.

It comes from hotter components of the West Atlantic, together with the Caribbean and Gulf of Mexico. It is a colorless, mottled-grey fish missing the distinguishing options of most different groupers.

Its pattern of markings resembles the box-shaped spots of the black grouper (Mycteroperca bonaci). It lacks the streamer factors on the tail fin that scamp (M. phenax) and yellowmouth grouper (M. interstitialis) have, and lacks yellow coloration across the mouth.

Distribution

Mycteroperca microlepis has discovered within the western Atlantic Ocean the place it has a disjunct distribution. The northern inhabitants are discovered around Bermuda and alongside the eastern coast of the United States from North Carolina south to Yucatan Peninsula of Mexico however, it’s largely absent from Cuba, other than one file of a vagrant.

The southern inhabitants are present in southern Brazil from Rio de Janeiro State to Santa Catarina State. Juveniles have been recorded in as far north as Massachusetts.

Appearance

Gag grouper has long, compressed our bodies.

Their coloring varies with their size. Large gags are darkish brownish-grey above and paler under, with traces of darkish wavy markings on the edges.

Smaller fish are a lot lighter and have darkish brown or charcoal kiss-like marks alongside their sides.

Gag’s scientific species name, microlepis, is derived from the Greek phrases “micro” for small and “lepis” that means scale, in reference to the small scales of this fish.

Gag grouper Description

Mycteroperca microlepis, gag grouper has a rectangular, sturdy body that is laterally compressed. The depth of the body is generally lower than the size of the top and it’s often roughly equal in-depth on the origin of the dorsal fin and on the anal fin origin.

The standard size is three to 3 and a half instances of the depth of the body. The dorsal profile of the top is convex and the preopercle has a rounded lobe at its angle which is has enlarged serrations.

The dorsal fin incorporates 11 spines and 16-18 smooth rays whereas the anal fin incorporates 3 spines and 10-12 smooth rays. The membranes between the dorsal fin spines are notched with the third and fourth spines being the longest.

The caudal fin is square. The adult females and the juveniles are usually pale gray to brown-grey marked with darker blotches and wavy strains that give a marbled look to the higher flanks and back.

The pelvic, anal, and caudal fins have bluish-black margins. When resting they usually assume a camouflage pattern with 5 darkish brown saddles separated by white bars alongside the bottom of the dorsal fin.

The massive adult males are usually pale to medium gray in color, with a vague reticulated pattern beneath the dorsal fin.

They are darker gray or black on the breast and stomach, with an analogous color on the margins of the smooth rayed part of the dorsal discovers the caudal fin, in addition to the posterior margins of the pectoral and pelvic fins.

There can also be a color part referred to as “black-back” which has the rear end of the body and all the smooth rayed part of the dorsal fin and the anal fin is black.

This species attains a most total size of 145 centimeters (57 in) though 50 centimeters (20 in) is a more frequent size, and the utmost printed weight attained is 36.5 kilograms (80 lb).

Gag grouper Biology

Mycteroperca microlepis, gag grouper have completely different habitat preferences as juveniles and adults. The juveniles are present in estuaries and beds of seagrass whereas the adults are discovered farther offshore over rocky substrates at depths of 40 to 10 meters (131 to 33 ft) and have been recorded as deep as 152 meters (499 ft).

Adults are sometimes recorded inshore over rock sea beds or seagrass beds. It is likely one of the commonest species of grouper on the eastern Gulf of Mexico.

They may be discovered each in brackish and marine waters. The adults may be discovered both in teams of 5-50 fish or as solitary fish.

They have been recorded producing thumping sounds when below stress, which is executed by vibrating the swim bladder utilizing muscular contractions.

The adults are predators on fishes (together with smaller conspecifics), crabs, shrimps, and cephalopods whereas the smaller juveniles prey on crustaceans inside the beds of seagrass in shallow waters. The fishes preyed are largely herring, sea bream, jacks and pompanos, drums, and gray mullet.

Gag grouper Breeding

This gag grouper species is a protogynous hermaphrodite, all fish start life as females, attaining sexual maturity between the ages of 5 and 6 years old and having reached a total size of 67 to 75 centimeters (26 to 30 in), they are going to spawn at the least as soon as after which some will change sex and change into males.

In the offshore waters between North Carolina and Florida throughout 1976-1982 the sex ratio was discovered to favor females, with 84% of the inhabitants being feminine, 15% had been males and 1% had been within the process of sex change.

However, a subsequent study found that the proportion of males had decreased to around 5.5%, fishing pressures that are targeting massive males being the possible reason behind this end result.

Although the sex change can happen as early as 5 years old it’s more typical for it to happen at 10 to 11 years old and at a total size between 95 to 100 centimeters (37 to 39 in).

In the Atlantic coastal waters between North Carolina and Florida, there are annual migrations in late winter, these migrations contain sexually mature fishes shifting to offshore spawning grounds the place at depths of 70 meters (230 ft).

The spawning season in this area runs from December by way of May, peaking in late March and early April. In the eastern Gulf of Mexico, the spawning season runs from late December by way of April, right here it peaks in February and April.

After spawning the female’s transfer in the direction of shallower waters, with depths lower than 30 meters (98 ft) whereas the males favor waters of fifty to 90 meters (160 to 300 ft) They most recorded age is 31 years.

Status

There are two shares of gag: South Atlantic and the Gulf of Mexico. According to the latest inventory assessments:

The South Atlantic inventory will not be overfished (2014 inventory evaluation) and isn’t subject to overfishing primarily based on 2019 catch knowledge. Summary inventory evaluation information may be discovered on Stock SMART.

The Gulf of Mexico inventory will not be overfished (2016 inventory evaluation) and isn’t subject to overfishing primarily based on 2018 catch knowledge.

Summary inventory evaluation information may be discovered on Stock SMART. This inventory had been overfished and was efficiently rebuilt in 2014.

Threats

Mycteroperca microlepis, gag grouper is focused on industrial and leisure fisheries utilizing handline, backside longline, and speargun.

Fishermen goal the spawning aggregation whereas the juveniles are steadily caught as bycatch within the bait-shrimp fishery that fishes over seagrass beds.

There have been studies of ciguatera poisoning amongst people following the consumption of flesh from M. microlepis. This species is threatened by and is weak to overfishing and Mexico and the United States have launched conservation measures.

SeaFish

Gag Grouper – Profile | Traits | Facts | Breeding | Catch