Redescription of Philometra margolisi Moravec, Vidal-Martínez et Aguirre-Macedo, 1995 (Nematoda: Philometridae), a gonad-infecting parasite of the red grouper Epinephelus morio (Serranidae) in the Gulf of Mexico

To be as accurate as possible, stock assessments should account for discard mortality in fisheries if it occurs. Three common approaches to modeling discards in assessments are to lump dead discards with landings, treat dead discards as their own fleet, or link them conversely with landings through use of a retention function. The first approach (lumping) implicitly assumes that the selectivity of landings applies also to discards. In many cases, that assumption is false, for example, if discards comprise smaller fish than do landings. The latter two approaches avoid the assumption by modeling discards explicitly with their own selectivity pattern. Here, we examine these approaches to modeling discards. Using a simulation study, we demonstrate that the two approaches to modeling discards explicitly can provide identical results under both static and time-varying conditions. Then, using a stock assessment case study of red grouper Epinephelus morio in the U.S. Gulf of Mexico, we demonstrate that in practice the approaches to modeling discards can provide different outcomes, with implications for the resultant management advice. We conclude by comparing and contrasting the different approaches, calling for more research to elucidate which approach is most suitable under various sources of error typically encountered in discard data.

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Spatial dynamics of the red grouper Epinephelus morio (Pisces: Serranidae) on the Campeche Bank, Gulf of Mexico

Scientia Marina ◽

10.3989/scimar.03565.13b ◽

2013 ◽

Vol 77 (2) ◽

pp. 313-322 ◽

Cited By ~ 3

Author(s):

Jorge A. López-Rocha ◽

Francisco Arreguín-Sánchez

Keyword(s):

Gulf Of Mexico ◽

Spatial Dynamics ◽

Epinephelus Morio ◽

Red Grouper

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Ontogenetic spatial distributions of red grouper (Epinephelus morio) and gag grouper (Mycteroperca microlepis) in the U.S. Gulf of Mexico

Fisheries Research ◽

10.1016/j.fishres.2017.04.006 ◽

2017 ◽

Vol 193 ◽

pp. 129-142 ◽

Cited By ~ 17

Author(s):

Arnaud Grüss ◽

James T. Thorson ◽

Skyler R. Sagarese ◽

Elizabeth A. Babcock ◽

Mandy Karnauskas ◽

...

Keyword(s):

Gulf Of Mexico ◽

Spatial Distributions ◽

Epinephelus Morio ◽

Red Grouper ◽

Gag Grouper ◽

The U.S ◽

Mycteroperca Microlepis

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Benthic Habitat Modification through Excavation by Red Grouper, Epinephelus morio, in the Northeastern Gulf of Mexico

The Open Fish Science Journal ◽

10.2174/1874401x01003010001 ◽

2010 ◽

Vol 3 (1) ◽

pp. 1-15 ◽

Cited By ~ 35

Author(s):

Felicia C. Coleman ◽

Christopher C. Koenig ◽

Kathryn M. Scanlon ◽

Scott Heppell ◽

Selina Heppell ◽

...

Keyword(s):

Gulf Of Mexico ◽

Habitat Modification ◽

Benthic Habitat ◽

Epinephelus Morio ◽

Red Grouper ◽

Northeastern Gulf Of Mexico

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Philometra margolisi n.sp. (Nematoda: Philometridae) from the gonads of the red grouper, Epinephelus morio (Pisces: Serranidae), in Mexico

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-522 ◽

1995 ◽

Vol 52 (S1) ◽

pp. 161-165 ◽

Cited By ~ 15

Author(s):

František Moravec ◽

Victor M. Vidal-Martínez ◽

Leopoldina Aguirre-Macedo

Keyword(s):

Body Shape ◽

Nematode Species ◽

Outer Circle ◽

Epinephelus Morio ◽

Red Grouper ◽

Gravid Females ◽

Lateral Papilla ◽

Shape And Size

A new nematode species, Philometra margolisi n.sp., is described from the gonads of the serranid fish Epinephelus morio from Mexico (localities Telchac, Chuburna, Progreso, and Rio Lagartos, Yucatan). It is characterized mainly by long (0.432–0.468 mm) and slender spicules and a simple gubernaculum (length 0.084–0.093 mm) in the male and by body shape and size (length 65–85 mm), arrangement and number of small cephalic papillae (eight papillae in an outer circle and four in an inner one), structure and length (1.07–1.18 mm) of the esophagus, long ovaries, and the presence of a pair of small lateral papilla-like projections on the elongate caudal end in gravid females.

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TEMPORAL VARIATION IN THE RED GROUPER, EPINEPHELUS MORIO, DEMOGRAPHIC STRUCTURE FROM SOUTHERN GULF OF MEXICO

Revista Ciencias Marinas y Costeras ◽

10.15359/revmar.2.3 ◽

2010 ◽

Vol 2 ◽

pp. 39

Author(s):

Doralice Caballero-Arango ◽

Thierry Brule ◽

Jorge L. Montero-Muño ◽

Teresa Colás-Marrufo

Keyword(s):

Gulf Of Mexico ◽

Sex Ratios ◽

Demographic Structure ◽

Size Frequency Distribution ◽

Frequency Distributions ◽

Size Frequency ◽

Epinephelus Morio ◽

Red Grouper ◽

Bank Stock ◽

Dependent Samples

Changes in the demographic structure of red grouper Epinephelus morio from the southern part of the Gulf of Mexico, were evaluated during periods when total catches, CPUE and annual yields of the specie decreased. Fishery-dependent samples (n = 1887) were obtained between August 1989 and February 2004 from the Campeche Bank, and size-frequency distributions by sex, sex ratios and sizes of sexual maturation and sex change were compared between three periods: P11989-1992 (n = 886); P21996-1998 (n = 413); and P32003-2004 (n = 588). The temporal stability of size-frequency distribution by sex, with males always being larger than females, and the sex ratios always biased towards females, were consistent with this species’ type of sexuality. Size for females and males, as well as sizes at first sexual maturity and at sex reversal all decreased from the oldest period to the more recent one and could be a consequence of the fishing intensity applied to this stock. The reductions in size of females and males associated with a relatively stable sex ratio and the lack of any drastic decrease in the number of males can be explained by this species’ reproductive ecology. Results are discussed regarding the capacity for reproductive resilience of red grouper in response to fishing pressure like that currently experienced by the Campeche Bank stock.

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