Life Sciences Commons^™

Fluorescence And Size Characterization Of Dissolved Organic Matter In Riverine And Sea Waters In The Northern Gulf Of Mexico, Zhengzhen Zhou

Dissertations

Riverine export of dissolved organic matter (DOM) is an important component in marine carbon budget but the composition and phase partitioning are poorly quantified. Monthly water samples were collected from the lower Mississippi and Pearl rivers between January 2009 to August 2011 for DOM characterization using the fluorescence excitation emission matrix (FluoEEM) technique, coupled with parallel factor analysis (PARAFAC), and flow field-flow fractionation technique. DOM in the Pearl River showed higher dissolved organic carbon (DOC) concentration, temporal fluctuation, and aromaticity, reflecting instantaneous inputs of DOM from local soil and plant litter. In contrast, DOM in the Mississippi River exhibited lower …

Nutrient Depletion As A Proxy For Microbial Growth In Deepwater Horizon Subsurface Oil/Gas Plumes, Alan M. Shiller, Dongjoo Joung

Faculty Publications

The Deepwater Horizon accident resulted in a substantial uncontrolled hydrocarbon release to the northern Gulf of Mexico, much of which was entrained in deep submerged plumes. While bio-degradation of the hydrocarbons has been inferred from microbial biomass and genetics, the amount of conversion of oil and gas carbon to biomass remains uncertain having only been estimated in modeling studies. Here we examine correlated depletions of nitrate, phosphate and oxygen in the submerged plumes and conclude that a substantial portion of hydrocarbons in these plumes was converted to biomass (0.8-2 x 10(10) mol C). This contrasts with nutrient-limited surface waters where …

Effects Of Hypoxia And 4-Tert-Octylphenol On Gene Expression Profiles Of The Sheepshead Minnow (Cyprinodon Variegatus), Arthur Alan Karels

Dissertations

Hypoxia occurs in estuaries of northern Gulf of Mexico and world-wide, with increasing frequency/severity via eutrophication and anthropogenic influences. Hypoxia inducible factors (HIFs) form transcriptional complex and bind DNA at hypoxia responsive elements (HREs) in promoter regions of genes needed for systemic and cellular adaptation of fish to low dissolved oxygen (hypoxia, DO <2.0 mg/ml). Hypoxia-induced activation of HIF-αs can lead to a cascade of downstream activation, such as erythropoietin (EPO). Return to normal DO levels (normoxia), prolyl hydroxylases (PHDs) are activated to degrade HIF-αs back to baseline. Fish are affected by environmental estrogen mimics, like 4-tert-octylphenol (4tOP), binding estrogen receptor alpha (ERα) at estrogen responsive elements (EREs) and activating genes vitellogenin (VTG). Previous research showed overlap or crosstalk between these two mechanistic pathways. Hypoxia triggers unknown factors regulating ERE-mediated ERα signaling pathway, and stressor combinations could increase/decrease hypoxic or endocrine pathway. Research examined molecular/physiological effects of hypoxia (acute and chronic, moderate and severe) and 4tOP (~60μg/L)on adult male and/or female sheepshead minnow (Cyprinodon variegatus). Three genes identified, cloned, and sequenced (HIF-1α, HIF-2α, and PHD3), plus previously identified genes EPO and VTG, were examined in liver/testes exposed to hypoxia and/or 4tOP for cellular/physiological changes. Endpoints examined included mRNA expression from real-time PCR of HIF-1α, HIF-2α, PHD3, EPO, and VTG using cDNA from total RNA extracts, and microarray analyses of genes expressed during the transition from hypoxia back to normoxia. Phylogenetic analyses confirmed isolation of two HIF-α isofoms (HIF-1α and HIF-2α) and the PHD3 isoform. Significant up-regulation of PHD3 occurred within 10 hrs of chronic hypoxia, and persisted when severe (1.5 mg/L) and declined when moderate (~2.5mg/L). Significant up-regulation of HIF-1α and EPO occurred within 30 minutes to 2 hours of onset of acute severe and very severe (~1.08mg/L) hypoxia. Hypoxia acted similar to an estrogen mimic, with huge up-regulation of VTG gene expression in males, and increased VTG levels (additive effect) when hypoxia was combined with 4tOP. Microarray analyses showed 125 genes with significant transcriptional change, with up- or down-regulation from transitions of: (1) hypoxia (72 hrs) to normoxia (74 hrs) and (2) hypoxia+4tOP (72 hrs) to normoxia+4tOP (74 hrs).

Thermal Tolerance Of Age-0 Gulf Of Mexico Striped Bass (Morone Saxatilis): Ontogenetic And Genetic Effects, Corey Robert Anderson

Master's Theses

Striped bass, Morone saxatilis, were historically abundant in the Gulf of Mexico region but were largely extirpated from most Gulf rivers by the early 1960s. Since 1967 hatchery stocking has supported populations in Mississippi rivers and to date there is no evidence of natural reproduction. Intolerance of striped bass to high water temperature is a potential factor negatively impacting Gulf striped bass survival and reproductive fitness, and may be a limiting factor to reintroduction of the species in Mississippi. This work contributed to restoration efforts by establishing molecular tools necessary for genetic monitoring of striped bass restoration, and evaluating …

A 50 Year Accomplishment In Marine Science: A History Of The Journal Published By The Gulf Coast Research Laboratory, Mark S. Peterson, Nancy J. Brown-Peterson, Sara E. Lecroy, Joyce M. Shaw, James S. Franks, Richard W. Heard

Gulf and Caribbean Research

The Gulf Coast Research Laboratory (GCRL) has a 50 year history of annual publication of the peer-reviewed journal Gulf and Caribbean Research (GCR, 2000-present; formerly Gulf Research Reports (GRR) from 1961—1999). Other extant journals serving the region during this time include Contributions in Marine Science (since 1945), Proceedings of the Gulf and Caribbean Fisheries Institute (since 1948), Bulletin of Marine Science (since 1951), Revista de Biología Tropical (since 1953), and Caribbean Journal of Science (since 1961). In the early years of the GCR publication, papers were primarily concerned with research in Mississippi and the northern Gulf of Mexico (GOM), and …

Life History And Habitat Use Of The Juvenile Alabama Shad (Alosa Alabamae) In Northern Gulf Of Mexico Rivers, Paul Fraser Mickle

Dissertations

The Alabama shad, Alosa alabamae, is an anadromous species that is in decline and has seen extirpations from impoundments as well as decreased water quality. Alabama shad live in the Gulf of Mexico and ascend Northern Gulf of Mexico Drainages to reproduce early in the year (January-May). The juveniles spend the majority of the year in these freshwater systems before emigrating out to the Gulf of Mexico as late as December.

This dissertation focuses on the juvenile life stages that occur within the Northern Gulf of Mexico drainages. Spawning conditions of the river, as well as the habitat and diet, …

Recruitment And Colonization Of Macroalgae To A Newly Constructed Rocky Intertidal Habitat In The Northwest Gulf Of Mexico, Ryan L. Fikes, Roy L. Lehman

Gulf and Caribbean Research

Marine macroalgal assemblages on artificial structures play an important ecological role in coastal and estuarine ecosystems and may supplement natural communities in nearby waters. The rocky jetties of Packery Channel, located near Corpus Christi, Texas represent a recent addition of hard structure for colonization in the northwest Gulf of Mexico. The purpose of this research was to monitor the initial immigration of macroalgal species during the first year of colonization and determine the effects of wave energy on recruitment. Ten sampling sites were established along the offshore portion of the new Packery Channel jetties. Samples were taken bimonthly from along …

Endohelminths Of A Snake Mackerel, Gempylus Serpens (Trichiuroidea: Gempylidae), From The Gulf Of Mexico, Charles K. Blend, Norman O. Dronen, James S. Franks, George W. Benz

Gulf and Caribbean Research

Endohelminths are reported from a female snake mackerel, Gempylus serpens (Trichiuroidea: Gempylidae), captured from a depth of 61 m in the Gulf of Mexico 140 km south of the mouth of Mobile Bay, AL, in August 1998. A diverse endohelminth parasite fauna was found: 29 plerocercoid type I tetraphyllideans from the lower intestine; 4 didymozoid metacercariae allocated to the collective group Monilicaecum and one didymozoid metacercaria of the collective group Torticaecum from the pyloric cecum; one juvenile Gonocerca phycidis from the stomach; and 5 larvae (L3 stage) comprising 3 species of Anisakis from the pyloric cecum. These nematodes were identified …

Factors Influencing The Environmental Quality Of The Bay Of Saint Louis, Mississippi And Implications For Evolving Coastal Management Policies, Pradnya Ankush Sawant

Dissertations

The Bay of St. Louis, MS is a small northern Gulf of Mexico estuary that has been identified by the Mississippi Department of Environmental Quality (MDEQ) as an impaired waterbody for its designated uses, mainly due to the presence of pollutant pathogens. A systematic study of this estuary was important to understand the behavior and responses of the bay to several natural and anthropogenic forcing factors. A 14- month long study (bimonthly sampling) to evaluate its environmental quality was undertaken from April 2003 to May 2004. Environmental quality was defined as "the health of an ecosystem characterized in terms of …

First Record Of Ceratapsis Monstrosa, A Larval Oceanic Penaeoid Crustacean, From The Gulf Of Mexico, James S. Franks, Adrienne Russell Flowers

Gulf and Caribbean Research

The genus Cerataspis (Gray, 1838) (Crustacea, Decapoda), assigned to the Penaeoidea by Burkenroad (1936) and Heegaard (1966), has circumglobal distribution between 40ºN and 40ºS (Morgan et al. 1985) and is represented in the Atlantic Ocean by two rarely collected species, C. monstrosa and C. petiti. Descriptions of both species are based on the larval forms since their adult form remain undescribed (Morgan et al. 1985). Although the larval development of Cerataspis is described by five mysis stages (I-V) (Heegaard 1966), the large larva is very un-mysid like and appears more like that of a megalops with the abdomen bend …

Large Pelagic Fishes In The Caribbean Sea And The Gulf Of Mexico: Current Status And Integrated Management, Mark S. Peterson, Nancy J. Brown-Peterson, James S. Franks

Gulf and Caribbean Research

A symposium convened on 7 November 2006 in conjunction with the 59th annual meeting of the Gulf and Caribbean Fisheries Institute in Belize City, Belize.

Relative Abundance Of Pelagic Sharks In The Western North Atlantic Ocean, Including The Gulf Of Mexico And Caribbean Sea, Enric Cortes, Craig A. Brown, Lawrence R. Beerkircher

Gulf and Caribbean Research

Little information exists on the status of pelagic shark populations in the Atlantic Ocean, especially in the Gulf of Mexico and Caribbean Sea. We derived indices of relative abundance for pelagic sharks based on mandatory logbooks and observer reports from a scientific observer program of the United States (US) pelagic longline fleet. Time series data from the pelagic longline logbook program (1986-2005) and the pelagic longline observer program (1992-2005) were standardized with Generalized Linear Model (GLM) procedures. Declines in relative abundance for the 6 pelagic shark species or genera examined in the logbook data analysis ranged from 43% for mako …

Patterns Of Vertical Habitat Use By Atlantic Blue Marlin (Makaira Nigricans) In The Gulf Of Mexico, Richard T. Kraus, Jay R. Rooker

Gulf and Caribbean Research

We examined data from pop-up archival transmitting (PAT) tags (n = 18) to characterize aspects of vertical habitat use by blue marlin (Makaira nigricans) from the Gulf of Mexico (GOM). Two of these tags were recovered and provided fine-scale information about diving patterns and the relationship between time at depth and temperature. Similar to previous studies, blue marlin in the GOM spent most of their time at the surface and at temperatures within 3° C of surface temperatures. Time at depth was multimodal and the magnitude of the smaller modes was dependent upon the strength and depth …

Distribution Of Molidae In The Northern Gulf Of Mexico, Gregory L. Fulling, Dagmar Fertl, Kevin Knight, Wayne Hoggard

Gulf and Caribbean Research

We compiled all available sighting, stranding and bycatch data for the Family Molidae (molas) in the northern Gulf of Mexico (NGOM) to assess spatial and temporal distribution. Overall, 483 records were collected from shipboard and aerial surveys, fisheries bycatch, and strandings. Molas were recorded year-round, with a ubiquitous distribution in both nearshore and offshore waters. Ocean sunfish (Mola mola) were sighted with greatest frequency during the winter (December thru April) in sea surface temperature < 24° C. Potential reasons for increased sightings during winter may be related to the lack of a well-defined thermocline in the NGOM; the species' "basking" behavior associated with thermoregulation; and oxygen replenishment after long, deep dives to oxygen-deficient depths.

Management In The Gulf And Caribbean: Mosaic Or Melting Pot?, Patrick Mcconney, Hazel A. Oxenford, Milton Haughton

Gulf and Caribbean Research

Does ''managing large pelagic fishes" mean the same thing across the diversity of maritime jurisdictions, governance arrangements, economies, languages, cultures, scales of operation and other features of the Gulf and Caribbean region? It would be surprising if it did. Yet international fisheries management urges this mosaic of management to become a melting pot; at least integrated, even if differentiated. This paper examines some themes underlying whether a mosaic or melting pot is the most apt metaphor for where we are, and are headed, in attempts to manage large pelagic fishes in the region. We pay particular attention to the multi-dimensional …

Marionia Tedi Ev. Marcus, 1983 (Nudibranchia, Tritoniidae) In The Gulf Of Mexico: First Record Of An Opisthobranch Mollusk From Hydrocarbon Cold Seeps, Angel Valdes

Gulf and Caribbean Research

Cold seeps in the Gulf of Mexico contain relatively diverse molluscan assemblages primarily composed of species that support chemoautotrophic symbionts, such as vesicomyid and mytilid bivalves, but also numerous species of shelled gastropods, bivalves, monoplacophorans, and polyplacophorans (Cordes 2004).

Recent exploration of hydrocarbon seep sites in the Mississippi Canyon and the Vioska Knoll revealed the presence of an unidentified species of nudibranch. The present paper describes the single specimen collected, which constitutes the first published record of an opisthobranch mollusk from a cold seep. The material examined is deposited at the Field Museum of Natural History (FMNH).

Manatee Occurrence In The Northern Gulf Of Mexico, West Of Florida, D. Fertl, A.J. Schiro, G.T. Regan, C.A. Beck, N. Adimey, L. Price-May, A. Amos, G.A.J. Worthy, R. Crossland

Gulf and Caribbean Research

Reports of West Indian manatees (Trichechus manatus) in the US Gulf of Mexico west of Florida have increased during the last decade. We reviewed all available manatee sighting, capture, and carcass records (n = 377) from Alabama, Louisiana, Mississippi, and Texas since the early 1900s; only 40 of these were previously published. Manatees were reported most often in estuarine habitats, usually either near a freshwater source or natural or industrial warm-water springs/runoffs during winter months. The recent increase in manatee records may be due to a combination of increased public awareness and dispersal of manatees, most likely seasonal …

High Cyanobacterial Abundance In Three Northeastern Gulf Of Mexico Estuaries, Michael C. Murrell, Jane M. Caffrey

Gulf and Caribbean Research

Aquatic phytoplankton comprise a wide variety of taxa spanning more than 2 orders of magnitude in size, yet studies of estuarine phytoplankton often overlook the picoplankton, particularly chroococcoid cyanobacteria (cf. Synechococcus). Three Gulf of Mexico estuaries (Apalachicola Bay, FL; Pensacola Bay, FL; Weeks Bay, AL) were sampled during summer and fall 2001 to quantify cyanobacterial abundance, to examine how cyanobacterial abundance varied with hydrographic and nutrient distributions, and to estimate the contribution of cyanobacteria to the bulk phytoplankton community. Cyanobacterial abundances in all 3 estuaries were high, averaging 0.59 ± 0.76 X 10⁹ L^–1 in Apalachicola Bay, …

Stomatopoda (Crustacea: Hoplocarida) From The Shallow, Inshore Waters Of The Northern Gulf Of Mexico (Apalachicola River, Florida To Port Aransas, Texas), John M. Foster, Brent P. Thoma, Richard W. Heard

Gulf and Caribbean Research

Six species representing the order Stomatopoda are reported from the shallow, inshore waters (passes, bays, and estuaries) of the northern Gulf of Mexico limited to a depth of 10 m or less, and by the Apalachicola River (Florida) in the east and Port Aransas (Texas) in the west. With the exception of the “live bottom” gonodactylid, Neogonodactylus bredini (Manning), these predatory crustaceans usually inhabit burrows in mud, sand-mud, and sand substrata in coastal and shelf waters. The species treated in this paper are Neogonodactylus bredini (Manning), Lysiosquilla scabricauda (Lamarck), Bigelowina biminiensis (Bigelow), Coronis scolopendra Latreille, Squilla empusa Say, and Gibbesia …

Tanaidacea (Crustacea: Peracardia) Of The Gulf Of Mexico. X. The Question Of Being Male, Kim Larsen

Gulf and Caribbean Research

Three new species Parafilitanais mexicana, Collettea elongata, and Paragathotanais medius are described from deep-sea localities in the Gulf of Mexico. The male of Parafilitanais does not vary conspicuously from the female, except for possessing pleopods. Male Paragathotanais reveal that the mouthparts display some degree of sexual dimorphism. Males of all 3 species possess functional mouthparts. The problems identifying male Tanaidacea are discussed. The number of terminal spiniform setae on the maxillule is considered invalid as a diagnostic character. Keys to the species of Parafilitanais and Paragathotanais are given.

Tanaidacea (Crustacea: Peracardia) Of The Gulf Of Mexico. Ix. Geographical Occurrence Of Apseudes Olimpiae Gutu, 1986 With A Review Of Previous Records For The Genus Apseudes In The Gulf, Tom Hansknecht, Richard W. Heard

Gulf and Caribbean Research

Examination of tanaidacean specimens collected from shelf waters of the eastern Gulf of Mexico (Gulf) revealed the presence of the apseudomorph Apseudes olimpiaeGutu, 1986, whose type locality was unknown, but suspected to be Bermuda. It is now determined that the type material actually came from the northeastern Gulf. Although the specific station locality information for the type material has been lost; records indicate that specimens from the Gulf were sent to Romania for study by M. Băcescu and apparently became mixed with material from Bermuda. Based on additional material from the present study, new locality records are established for …

Oceanic And Neritic Ichthyoplankton At The Edge Of The Continental Shelf In The Southern Gulf Of Mexico, Cesar Flores-Coto, Fernando Flores-Hernandez, Faustino Zavala-Garcia, Virgilio Arenas-Fuentes, Maria Adela Monreal-Gomez, David Alberto Salas-De-Leon

Gulf and Caribbean Research

Oceanic and neritic ichthyoplankton were examined at a single sampling site at the edge of the continental shelf in the southern Gulf of Mexico. Double oblique tows were made with a 60 cm Bongo net fitted with 505 µm mesh netting. Collections were taken every 2 hours over a 24 h period during spring, summer and fall of 1992. Fish larvae were described as either oceanic or neritic depending upon adult lifestage habitat. The larvae of 59 taxa were collected in spring (50 oceanic, 9 neritic), 53 in summer (26 oceanic, 27 neritic) and 55 in fall (22 oceanic, 33 …

Fecundity Of Litopenaeus Setiferus, Farfantepenaeus Aztecus And F. Duorarum, In The Southwestern Gulf Of Mexico, Martin Perez Velazquez, Adolfo Gracia

Gulf and Caribbean Research

Fecundity of white shrimp, Litopenaeus setiferus, brown shrimp, Farfantepenaeus aztecus, and pink shrimp F. duorarum and relationships to gonad weights and total and carapace length were estimated. Ovigerous females were collected in the southern Gulf of Mexico in February, May, August and November 1993. Fecundity was estimated by means of a gravimetric method. The equations relating fecundity to total weight and fecundity to gonad weight were linear in the 3 species. However, an exponential relationship was found between fecundity and carapace length in L. setiferus and F. aztecus. Of the relationships examined, gonad weight was considered a …

The South American Neritic Copepod Ctenocalanus Heronae Vega-Pérez And Bowman (Calanoida) In The Gulf Of Mexico, With Comments On The Taxonomy Of The Genus, E. Suarez-Morales, A. Leon-Oropeza

Gulf and Caribbean Research

A single adult female specimen of the calanoid copepod Ctenocalanus heronaeVega-Pérez and Bowman was collected during a zooplankton survey carried out in February 1997 in Campeche Sound, the central-southeastern portion of the Gulf of Mexico. The taxonomy of the genus Ctenocalanus Giesbrecht is still unclear. Characters used to separate the species have been considered rather subtle. In this paper the taxonomic illustrations of the specimen collected are accompanied by a revision of the taxonomic features commonly used to identify the species. New, previously overlooked characters such as the cephalosome/urosome ratio, the shape of the 5th legs and particularly the …

An Illustrated Record And Range Extension Of Caligus Chelifer (Copepoda, Siphonostomatoida) In The Gulf Of Mexico, E. Suarez-Morales, I. H. Kim, I. Lopez-Salgado

Gulf and Caribbean Research

A male specimen of the copepod Caligus chelifer Wilson, 1905, was collected during a plankton survey carried out during February 1994 off the Mexican coasts of the eastern Gulf of Mexico (Tamaulipas state). This is the first record of this species in Mexican waters and south of the 25ºN in the Northwestern Atlantic. Taxonomic illustrations of the specimen are provided.

Feeding Of Sciaenid (Pisces: Sciaenidae) Larvae In Two Coastal Lagoons Of The Gulf Of Mexico, Alberto Ocana-Luna, Marina Sanchez-Ramirez

Gulf and Caribbean Research

Stomach contents analyses showed that Leiostomus xanthurus (8.50-12.90 mm SL) had a wide trophic spectrum (15 food categories) with copepods and eggs of invertebrates as main components. In contrast, Micropogonias undulutus (6.65-12.20 mm SL) ingested only six food categories (copepods, eggs of invertebrates, crustacean nauplii, bamacle nauplii, amphipods and other crustaceans). There is an overlap of 73.2 to 83.0% in the diet of these two species. Bairdiella chrysoura (1.17-1.92 mm SL) fed primarily on juvenile pelecypods, crustacean nauplii, eggs of invertebrates, including gasteropods and copepods. Cynoscion nebulosus (1.50-2.42 mm SL) ingested juvenile pelecypods, copepods, crustacean nauplii, eggs of invertebrates and …

Benthic-Pelagic Coupling In Northern Gulf Of Mexico Estuaries: Do Benthos Feed Directly On Phytoplankton?, Gary R. Gaston, Carol M. Cleveland, Steven S. Brown, Chet F. Rakocinski

Gulf and Caribbean Research

Few of the dominant benthic taxa of the northern Gulf of Mexico feed directly on phytoplankton. Rather, most of them feed on near-bottom seston and detritus. This is in contrast to models for Chesapeake Bay and San Francisco Bay. We found that detritivores represented over 80% of the macrobenthic organisms and over 90% of the biomass in Gulf of Mexico estuaries. The paucity of benthos that consumed phytoplankton led us to hypothesize that macrobenthos in Gulf of Mexico estuaries had less effect on plankton communities than was documented in U.S. east coast and west coast estuaries, where benthic communities consumed …

Observations Of Sea Turtles And Other Marine Life At The Explosive Removal Of Offshore Oil And Gas Structures In The Gulf Of Mexico, Gregg R. Gitschlag, Bryan A. Herczeg, Theresa R. Barcak

Gulf and Caribbean Research

Observers monitored the explosive removal of oil and gas structures in the Gulf of Mexico to protect sea turtles and marine mammals from adverse impacts. More than 7,000 monitoring hours at 131 structure removals were conducted during 1993. Sixteen individual sea turtles were observed including 6 loggerheads, 1 Kemp's ridley, 1 green, and 8 unidentified sea turtles. Aerial surveys were approximately ten times more effective in observing sea turtles than day or night surface surveys.

Northern Record For The Zooxanthellate Scleractinian Coral Siderastrea Siderea (Ellis And Solander) From The Gulf Of Mexico, William W. Schroeder, Thomas S. Hopkins

Gulf and Caribbean Research

We report a northward range extension of the zooxanthellate scleractinian coral Siderastrea siderea (Ellis and Solander) in the Gulf of Mexico. Several small, living colonies of S. siderea have been obtained in dredge samples from a site located at 29º 55.5' N, 087º 28.4' W in the northeastern Gulf of Mexico. Prior to these collections the northernmost occurrence of S. siderea in the Gulf of Mexico was reported as 27º 54.5' N, 093º 35.8' W, on the East Flower Garden Bank, in the western Gulf of Mexico. In the eastern Gulf of Mexico, S. siderea is not reported occurring on …

Gonadal Maturation In The Cobia, Rachycentron Canadum, From The Northcentral Gulf Of Mexico, Jeffrey M. Lotz, Robin M. Overstreet, James S. Franks

Gulf and Caribbean Research

Gonadal maturation of cobia, Rachycentron canadum, was evaluated by examining 508 specimens from its recreational fishery. Specimens were collected off southeast Louisiana to northwest Florida by hook-and-line during February through October 1987-1991. Fork lengths (FL) of these fish ranged from 580-1,530 mm, with corresponding weights of 2.0-43.5 kg. The female:male ratio was 1:0.37. Using a combination of oocyte size frequency and histological assessment of many of the fish, we determined that females were ripe from May through September, with atretic oocytes occurring in some fish from July through October. Degenerating hydrated oocytes in July and October and the presence …