Red Grouper
| Life History Parameters | Value |
|---|---|
| Maximum weight (kg) | 23 |
| Maximum age (year) | 29 |
| Age at length 0 (year) | -1.202 |
| Age at Maturity (months) | 34 |
| Maximum Length (cm) | 125 |
| Length at Maturity (cm) | 29 |
| Linf. Asymptotic Length (cm) | 82.9 |
| K - von Bertalanffy growth coefficient | 0.13 |
| Natural Mortality | 0.14 |
| - | Feb | Mar | Apr | May | Jun | - | - | - | - | - | - |
Habitat and Distribution
This species is associated with reefs and hard bottom habitats in the western Atlantic from North Carolina to Brazil, including the Gulf of Mexico and the Caribbean.
Spawning season in the Gulf of Mexico
The spawning season for this species varies by region. Most studies report that spawning occurs from late February to early June with peak spawning from March to May. However, spawning is reported to occur from January through March in the southern Gulf of Mexico.
Spawning Patterns
Red Grouper spawn offshore on low relief, hard bottom habitats covered by a thin veneer of sand and associated with boulders and cobble (i.e. karst topography with limestone solution holes) at an average depth of 70 m. They are protogynous hermaphrodites that are territorial, relatively sedentary, exhibit the typical haremic, pair-spawning mating system of protogynous fishes. Adults exhibit high site fidelity year-round and do not migrate to form spawning aggregations. During courtship spawning, females will exhibit a distinctive barred color pattern, whereas males will have black colored backs with white lines radiating from the eyes backward onto the black back. Individual females approach individual males, which occupy and guard excavated holes as home territories. Males will then follow and court the female, and when successful, they spiral and ascend up into the water column to spawn as a pair. Red Grouper are broadcast spawners with external fertilization. Individual females spawn every 5 days on average, with some evidence that older females spawn more frequently than younger females.
Fishing Patterns in Relation to Spawning
Commercial landings are consistent throughout the year and the greatest amount of landings vary between spawning and non-spawning months year to year. Recreational landings increase during the last two months of spawning (May and June) and peak in July and August.
Management of Spawning Aggregations
The commercial fishery is managed under the IFQ program and there are no seasonal closures. Net and spearing gear are prohibited in federal waters for the commercial fishery. The recreational fishery in federal waters is subject to a daily catch limit of 2 that must fit within a total catch limit of 4 similar grouper Catch limits in state waters are the same as the federal limit, or are slightly less restrictive. Texas rectricts recreational and commercial gear to hook and line only. The recreational fishery is closed Feb. 1 - Mar. 31 beyond 20 fathoms. The closure coincides with the first two months of the spawning season which lasts until June. Madison Swanson, Steamboat Lumps and the Edges are closed year round. The minimum size is 18" TL for commercial and 20" for recreational.