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Hyporthodus niveatus

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Life History Parameters Value
Maximum weight (kg) 30
Maximum age (year) 35
Age at length 0 (year) -2.884
Age at Maturity (months) 60
Maximum Length (cm) 122
Length at Maturity (cm) 60
Linf. Asymptotic Length (cm) 106.46
K - von Bertalanffy growth coefficient 0.09
Natural Mortality 0.19

Spawning Season (Peak month in bold):
Jan Feb Mar Apr May Jun Jul Aug Sep Oct - -

Habitat and Distribution

This species occurs in the western Atlantic from Massachusetts south to Brazil, including the Gulf of Mexico and the Caribbean. Both juveniles and adults occur on reefs and other hard bottom habitats.

Spawning season in the Gulf of Mexico

In the GOM, this species is reported to spawn from April to October. New research by Lowerre-Barbieri and colleagues (unpublished) reported the collection of spawning capable females in all months but June, November, and December. Actively spawning females were collected in July and October, whereas regenerating females were collected throughout the year. Based on these data, the spawning season in the GOM is estimated to occur from January through October.

Spawning Patterns

Little is known about the spawning patterns of Snowy Grouper in the Gulf of Mexico. However, courtship behavior of this species has been observed on deep, Oculina coral reefs where Gag and Scamp are known to aggregate for spawning. Snowy Grouper are thought to form resident spawning aggregations, as catch rates increase at certain sites during the spawning season, although this behavior has not confirmed or characterized. They are common on the outer continental shelf, where they are associated with high relief habitats characterized by ridge, terraces, and steep dropoffs and likely spawn in these habitats. Snowy Grouper are protogynous hermaphrodites and broadcast spawners with external fertilization.

Fishing Patterns in Relation to Spawning

Average monthly commerial landings were greater in spawning months than in non-spawning months 1997-2004 & 2010-2015. Recreational landings in spawning months are generally greater than non-spawning months and are highests in May - July, which coincides with the spawning season.

Management of Spawning Aggregations

The commercial fishery is managed under the IFQ program and there are no seasonal closures for either the commercial or recreational fishery. 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 4 that must fit within a total catch limit of 4 similar grouper. There are no state-level catch limits save for Texas, which set their catch limit to be the same as the federal limit. Madison Swanson, Steamboat Lumps and the Edges are closed year round.

Research and Management Priorities