Fisheries and Resources Monitoring System

EspañolFrançais
Gulf menhaden - Gulf of Mexico USA waters
Fact Sheet Title  Fact Sheet
Status of stocks and resources 2019
Gulf menhaden - Gulf of Mexico USA waters
Fact Sheet Citation  
Owned byFood and Agriculture Organization (FAO) – ownership
ident Blockident Blockdisplay tree map
 
Species List:
Species Ref: en - Gulf menhaden, fr - Menhaden écailleux, es - Lacha escamuda
ident Block Gulf menhaden - Gulf of Mexico USA waters
Aq Res
Biological Stock: Yes         Value: National
Management unit: Yes        Reference year: 2016
 
 
Aq Res State Trend
Aq Res State Trend
Aq Res State Trend Aq Res State Trend
Aq Res State TrendF2015/F30% = 0.11Not applicable
Aq Res State TrendSSB2015/SSB30% = 3.51Not applicable
Aq Res State Trend
Aq Res State TrendUnderfished

Gulf menhaden (Brevoortia patronus) is only reported to FAO by the United States of America. The most recent benchmark stock assessment (SEDAR, 2013a) used data for the period 1977-2011 and indicated that the stock was not overfished and overfishing was not occurring. A recent update of the benchmark assessment with data up to 2015 arrived at the same conclusions (Schueller, 2016).
Habitat Bio
Climatic Zone: Tropical.   Vertical Dist: Pelagic.  

Water Area Overview
Spatial Scale: National

Water Area Overview
Aq Res Struct
Biological Stock: Yes
Bio Assess
Uncertainty: Low

Data

Data up to 2016. The catch-age model included data from two sets of fishery-independent surveys and one fleet consisting of the commercial reduction landings, commercial bait landings, and recreational landings. The data sources used for this assessment were the same as those used for the benchmark assessment. The model was fitted to annual landings, annual age compositions of landings, two indices of abundance (seine juvenile abundance index and gillnet adult abundance index), and annual length compositions of the gillnet adult abundance index. 
Assess Models
Type:  Age-structured
Beaufort Assessment Model

The Beaufort Assessment Model (BAM) that was developed for the Gulf menhaden benchmark during SEDAR 32A was updated in this assessment. The BAM applies statistical catch-age formulation (Williams and Shertzer 2015) and was implemented with the AD Model Builder software (ADMB Foundation 2011).
Results

Total and Spawning Biomass (Fecundity) - Estimated biomass and biomass at age exhibited a largely similar pattern to that of abundance (Figures 13 and 14; Table 8). Total biomass was stable from 1977 until the mid-2000s, when the biomass started to increase. Estimated fecundity was stable from 1977 to the mid-1990s after which fecundity has increased until 2015 (Figure 15). - Fishing mortality - Estimated fishing mortality rates (F) were high from 1977 to the mid-1990s with the highest fishing mortality rates occurring in the mid-to late-1980s (Figure 18; Tables 9 and 10). After the mid-1990s, the fishing mortality rate has continued to decline, but at a slower rate. Figure 5 shows total predicted landings in weight. Commercial harvest exceeds 800,000 mt during much of the 1980s, but declined afterwards to stabilize between 400,000 and 500,000 mt for much of the past decade (Figure 5). - Status of the Stock and Fishery - Base run estimates of spawning stock biomass showed stability near the threshold during 1977 until the mid-1990s after which the SSB increased (Figure 15; Table 9). Current stock status in the base run was estimated to be SSB2015/SSB30% = 3.51 (Table 11). MCB analysis suggests that the stock status determination of being not overfished (i.e. SSB>SSB30%) has a low degree of uncertainty (Figures 21, 22, and 23). Over 99% of MCB runs were greater than SSB30% in the terminal year. The estimated time series F/F30% suggests that overfishing has occurred historically, but only prior to 1990 (Figure 21; Table 9). Currently fishery status in the terminal year is estimated in the base run to be F2015/F30% = 0.11 (Table 11). This estimate indicates that overfishing is not occurring and appears robust across MCB trials (Figures 22 and 23). Across all MCB runs, 99% of runs were less than F30% in the terminal year. The Gulf of Mexico Gulf menhaden population is not overfished and overfishing is not occurring. The base run and all sensitivity runs indicate the same stock status. In addition, most of the MCB trials indicated the same stock status. In general, there is very little risk of overfishing or of being overfished (Figure 24). 
Sci Advice

Recommendations for the Next Benchmark Assessment - The MAC recommends that the next peer-reviewed assessment occur during 2018. Gulf menhaden are a short-lived species and would benefit from a shorter time between assessments such as 2-3 years. During the next benchmark assessment four data items should warrant further consideration or are recommended by the MAC. First, bait landings should be more fully investigated in order to elucidate the magnitude and trajectory of landings over time. In particular, codes 100 and 125 should be investigated further to more clearly delineate the extent of bait landings versus landing offloaded at the reduction facility. While the magnitude of the landings is low in comparison to the commercial reduction landings, it is nonetheless important to provide as accurate of a picture of landings as possible. Therefore, the MAC also recommends that biological samples (length, weight, and a scale sample) be collected from the bait boat in LA in order to characterize the composition of the catch. Second, investigation and consideration of the new maturity and fecundity data provided by Brown-Peterson et al. (in review) should be undertaken. Preliminary sensitivity runs indicate that the changes in maturity and fecundity at age will lead to differences in the scale of the population spawning stock biomass. Third, the MAC recommends that biological samples (length, weight, and a scale sample) be collected from the state surveys being used to provide the indices of abundance. The biological samples will provide information to the assessment on the ages of the fish captured during the surveys and that are represented in the indices of abundance. Forth, the MAC recommends further consideration of the genetic data currently available. Genetic data can be used to inform the species range for the assessment. However, the main interest from the MAC regarding the genetic data is whether or not data need to be censored east of the 88-degree longitudinal line for the surveys comprising the abundance indices.
Management
Management unit: Yes
Sources
 
FAO. Western Central Atlantic Fishery Commission. 2019. Review of the state of fisheries and fisheries resources in the WECAFC region. Meeting document WECAFC/SAG/IX/2018/3 of the ninth session of the Scientific Advisory Group, Christ Church, Barbados, 19-20 November 2018.  Click to openhttp://www.fao.org/fi/static-media/MeetingDocuments/WECAFC/SAG2018/3e.pdf
Schueller, A. 2016. GDAR 02. Gulf menhaden stock assessment. 2016 Update. GSFMC No. 254. Gulf States Marine Fisheries Commission. Ocean Springs, MS. 75 pp.  Click to openhttps://www.gsmfc.org/publications/GSMFC%20Number%20254.pdf
Bibliography
 
FAO. Western Central Atlantic Fishery Commission/FAO Commission des pêches pour l’Atlantique Centre-Ouest/FAO Comisión Central de Pesca para el Atlántico CentroOccidental. 2019. Report of the ninth session of the Scientific Advisory Group, Christ Church, Barbados, 19-20 November 2018. Rapport de la neuvième session du Groupe scientifique consultatif, Christ Church, Barbade, 19-20 Novembre 2018. Informe de la octava sesión del Grupo Asesor Científico, Christ Church, Barbados, 19-20 de Noviembre de 2018. FAO Fisheries and Aquaculture Report/Rapport sur les pêches et l’aquaculture/Informe de Pesca y Acuicultura. No. 1266. Bridgetown, 156 pp.  Click to openhttp://www.fao.org/3/ca4776t/ca4776t.pdf
All references to figures, tables and bibliography in the text are found within the source of information.
powered by FIGIS  © FAO, 2024
Powered by FIGIS
crawl