Scientific Name
Mycteroperca microlepis

Common Name
Gag

Biology
Juveniles occur in estuaries and seagrass beds; adults are usually found offshore on rocky bottom (rarely to 152 m), occasionally inshore on rocky or grassy bottom. It is the most common grouper on rocky ledges in the eastern Gulf of Mexico. Adults are either solitary or in groups of 5 to 50 individuals; feed mainly on fishes, some crabs, shrimps, and cephalopods. Juveniles (less than 20 cm) feed mainly on crustaceans that live in shallow grass beds.

Classification

Classified By

Goode & Bean, 1879

Class

Ray-finned fishes (Actinopterygii)

Order

Perch-like fish (Perciformes)

Family

Sea basses: groupers and fairy basslets (Serranidae)

Distribution

Region

Western Atlantic

Distribution

Western Atlantic: North Carolina, USA (with juveniles occurring as far north as Massachusetts) to the Yucatan Peninsula, Mexico. Rare in Bermuda; one record in Cuba; also reported from eastern Brazil.

Range

40°N - 27°S, 98°W - 38°W

Environment

Climate

Subtropical

Water Temperature From

Unknown °C

Water Temperature To

Unknown °C

Depth From - meters

40 m

Depth To - meters

152 m

Zone

reef-associated

Environment

Marine; brackish; reef-associated; oceanodromous (Ref. 51243); depth range 40 - 152 m (Ref. 5222)

Trophic Level

3.65 s.e. 0.60 Based on diet studies.

Occurs in Marine / Salt water

True

Occurs in Brackish water

True

Occurs in Fresh Water

False

Occurs on Reefs

True

Is kept in Aquariums

False

Physical Size and Genetics

Maximum Length

145 cm

Common Length

50.0 cm

Phylogenetic Diversity Index

PD50 = 0.5000 many relatives (e.g. carps) 0.5 - 2.0 few relatives (e.g. lungfishes)

Human Uses and Population

Human Uses

Fisheries: highly commercial; gamefish: yes

Vulnerability

High to very high vulnerability (68 of 100)

Resilience

Low, minimum population doubling time 4.5 - 14 years (K=0.12-0.16; tm=3-8; tmax=16; Fec>10,000)

Threat To Humans

Harmless

IUCN Red List Status

Least Concern (LC) , IUCN Grouper and Wrasse Specialist Group