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Lessons From An Iconic Grouper: Sex, Science, And Serendipity, Yvonne J. Sadovy De Mitcheson

Gulf and Caribbean Research

From a common little damselfish and spectacular grouper aggregations, to disappearing reef fishes and the dark side of the international seafood trade, my journey has passed through a fascinating and worrying period of change in the way we view and treat our oceans. Although much of my career has been in the Indo—Pacific, I focus here mainly on my professional ‘roots’ in the Caribbean and on the Nassau Grouper Epinephelus striatus, a species that kept me curious, taught me patience, never to assume and always to stay hopeful. This fish is almost an obsession; why can we not better safeguard …

A Preliminary Assessment Of The Spawning Potential Ratio Of Five Target Species Of The Coastal Gillnet Fishery In Guyana And Suriname, Tomas Willems, Elford Liverpool, Michael Hiwat

Gulf and Caribbean Research

Data—limited stock assessment methods have the potential to positively impact livelihoods of fishermen around the world by providing management recommendations that aim to optimize sustainable yields from fisheries. Some years ago, a novel length— based (LB) method was developed for the assessment of spawning potential ratio (SPR), a measure of the reproductive capacity of fish stocks. We applied the LB—SPR method to 5 important target species of the coastal gillnet fishery in Guyana and Suriname. Nebris microps (Smalleye Croaker; 32% SPR) and Macrodon ancylodon (King Weakfish; 34% SPR) had the highest spawning potential, but remained below the 40% target level …

Jonathan Franco López 1955 – 2023, Angel Moran-Silva, Rafael Chávez-López, Sergio Cházaro-Olvera

Gulf and Caribbean Research

No abstract provided.

Life History Metrics Of Wahoo (Acanthocybium Solandri) From The Northern Gulf Of Mexico, Erik T. Lang, Chris A. Levron, Cijii D. Marshall, Brett J. Falterman

Gulf and Caribbean Research

Wahoo (Acanthocybium solandri) are highly sought in recreational and commercial fisheries in the Gulf of Mexico (GOM), yet the harvest of Wahoo is currently unmanaged in the GOM region outside of Florida waters. Life history metrics are critical to stock assessments and science-based management. Between 2014-2017, Louisiana Department of Wildlife and Fisheries (LDWF) biologists collected Wahoo otoliths and ovaries (n=198) from the northern GOM Wahoo recreational fishery based in Venice, LA to estimate life history metrics of age, growth, and maturity. A protocol was developed to section and age the small, fragile otoliths. A 2-parameter Von Bertalanffy growth …

Rangia Cuneata Clam Decline In Lake Pontchartrain From 2001 To 2014 Due To An El Niño Southern Oscillation Shift Coupled With A Period Of High Hurricane Intensity And Frequency, Michael A. Poirrier, Claire E. Caputo

Gulf and Caribbean Research

The clam, Rangia cuneata, occurs in low salinity zones of Atlantic and Gulf of Mexico estuaries. Prior to 2001, it was abundant in Lake Pontchartrain, a large and shallow oligohaline estuary, located north of New Orleans. However, abundance abruptly decreased by 96% after an extreme drought from an El Niño Southern Oscillation (ENSO) shift (1998-2000). Stable higher salinities resulted in the establishment of higher salinity communities. The hooked mussel, Ischadium recurvum, increased abruptly and colonized live R. cuneata. Competition from I. recurvum and the R. cuneata decline occurred at the end of the drought, despite a decrease …

What Is Known About Species Richness And Distribution On The Outer-Shelf South Texas Banks?, Harriet L. Nash, Sharon J. Furiness, John W. Tunnell Jr.

Gulf and Caribbean Research

The outer-shelf South Texas Banks, also known as the snapper banks, are known by fishermen to be excellent fishing grounds. However, few scientific studies have been conducted to describe the ecology of these uncommon but distinctive habitats. This paper describes results of a literature review and an assessment to determine what is known about the biota of the South Texas Banks and to assist in developing renewed interest and focus on these topographic highs. The outer-shelf South Texas Banks include relict coralgal reefs and relict barrier islands, and we also include data for a nearshore site, which is geographically and …

Observations At A Multispecies Parrotfish (Scaridae) Spawning Aggregation Site At Bermuda With Notes On The Predation Behavior Of Black Grouper (Mycteroperca Bonaci), Brian E. Luckhurst

Gulf and Caribbean Research

The objective of the present study was to describe the spawning behavior of three different species of parrotfishes at the same spawning aggregation site with detailed timing sequences. In addition, observations of other species known to form resident spawning aggregations (i.e., surgeonfishes) and the predatory behavior of black grouper (Mycteroperca bonaci) at this aggregation site are included.

Abundance And Distribution Of Two Species Of Squilla (Crustacea: Stomatopoda: Squillidae) In The Northern Gulf Of Mexico, Jennifer L. Wortham

Gulf and Caribbean Research

Stomatopods (mantis shrimps) are predatory benthic crustaceans. Mantis shrimp in the genus Squilla are frequent bycatch animals unintentionally collected in conjunction with the shrimp fishery in the Gulf of Mexico (GOM). Their carcasses are discarded instead of being retained for human consumption, fish meal, or other protein-based food products. The size, depth, salinity, and temperature distributions of these species, as well as their abundance based on gender, were examined to gain biological information that would be necessary if a fishery were to develop in the GOM. I collected samples (n = 2,854) of Squilla empusa and Squilla chydaea in the …

Whale Sharks Of The Western Caribbean: An Overview Of Current Research And Conservation Efforts And Future Needs For Effective Management Of The Species, Rachel T. Graham

Gulf and Caribbean Research

Whale sharks (Rhincodon typus) are seasonal visitors to four sites in the Western Caribbean, 3 of which are encompassed by the Mesoamerican Barrier Reef. Predictable encounters with the world's largest fish have raised this species' profile globally and led to several research and conservation efforts that aim to elucidate the need for information for the species management and balance the growing demand for highly lucrative encounter tourism. Tagging studies have demonstrated that the whale shark population is relatively small and likely forms a single population. Individuals move throughout the region between 3 of 4 known feeding sites and …

Fisheries Ecology Abstracts

Gulf and Caribbean Research

Abstracts of presentations from the Large Pelagic Fishes Symposium in Belize City, Belize during November 2006.

Ecology Of The Rock Shrimp Sicyonia Dorsalis Kingsley, 1878 (Crustacea: Sicyoniidae) In A Subtropical Region Of Brazil, Rogerio Caetano Da Costa, Adilson Fransozo, Maria Lucia Negreiros-Fransozo

Gulf and Caribbean Research

The present study analyzes the abundance and distribution of the rock shrimp Sicyonia dorsalis, in relation to water temperature, salinity, depth, organic matter content, and sediment texture in Mar Virado (MV), Ubatuba (UBA) and Ubatumirim (UBM), 3 distinct bays along the northern coast of São Paulo State (23°S, 45°W), Brazil. Six transects were taken in each bay, 4 being parallel to the coastline and 2 next to the rocky shores. Monthly samples were taken over a 2-year period (1998 and 1999) with a shrimp fishing boat equipped with double-rig nets. A total of 2,498 specimens was obtained with 804 …

Reproductive Structures And Early Life History Of The Gulf Toadfish, Opsanus Beta, In The Tecolutla Estuary, Veracruz, Mexico, Alfredo Gallardo-Torres, Jose Antonio Martinez-Perez, Brian J. Lezina

Gulf and Caribbean Research

Although the Gulf toadfish, Opsanus beta, is an abundant member of the nearshore Gulf of Mexico ichthyofaunal assemblage, little information exists regarding the ecology of the species, especially for southern Gulf of Mexico populations. We added to the existing knowledge of this species by describing the reproductive structures and examining the early life history of this species in the Tecolutla estuary, Mexico. Macro- and microscopic examination of 7 males showed spermatogenesis to be similar to other teleost species except for the occurrence of biflagellate spermatozoa. Histological examination of the male accessory gland showed 3 tissue layers, but their functions …

Spawning Aggregation Sites Of Snapper And Grouper Species (Lutjanidae And Serranidae) On The Insular Shelf Of Cuba, Rodolfo Claro, Kenyon C. Lindeman

Gulf and Caribbean Research

Twenty-one spawning aggregation sites on the Cuban shelf were identified for eight species of snappers (Lutjanus) and groupers (Epinephelus and Mycteroperca) using information from experienced fishers and field studies. Three sites are on the southeastern shelf, eight on the southwest shelf bordering the Golfo de Batabanó, two in the northwest, and eight in the north-central region along the margins of the Archipiélago de Sabana-Camagüey. These numbers may reflect sampling effort as much as absolute aggregation numbers, with most effort concentrated in the southwest and north-central regions. Additional studies, particularly field assessments, are needed to determine the …

Historic Trends In The Secchi Disk Transparency Of Lake Pontchartrain, J.C. Francis, M.A. Poirrier, D.E. Barbe, V. Wijesundera, M.M. Mulino

Gulf and Caribbean Research

A major environmental concern about Lake Pontchartrain is an assumed long-term increase in turbidity based on Secchi disk transparency observations. Regression of the available data on Secchi disk transparency versus time (1953 through 1990) reveals a statistically significant decrease in transparency of about 40%. However, the data set is biased in that it does not adequately represent the seasonal effects of salinity and wind speed. Two analytical procedures were undertaken to determine the extent to which the apparent long-term decrease in transparency was dependent on the seasonal bias. One procedure involved seasonal adjustment of the data for the effects of …

Autecology Of The Black Needlerush Juncus Roemerianus, Lionel N. Eleuterius

Gulf and Caribbean Research

Juncus roemerianus generally occupies the upper half of the intertidal plane and covers about 92% or 25,000 hectares of marsh in Mississippi. The vegetative canopy is best described as a series of disjunct and intergrading populations. Considerable phenotypic variation and differences in standing crop exist between populations. J. roemerianus has very wide environmental tolerances in comparison to all other tidal marsh angiosperms. Soil types inhabited by the rush range from very sandy to highly organic muds and peats, which may vary in the concentration of nutrient elements (nitrogen, phosphorus and potassium). Neither soil type, nutrient concentration, water content, pH nor …

Comments On Density Inversions In Marine Shallow Waters And Beyond, Gordon Gunter, Forrest V. Durand

Gulf and Caribbean Research

It has been shown within the past 70 years that salinity and thus density inversions are often detectible in shallow bays and estuaries. This terminology means that surface salinities are sometimes higher than those at lower depths. The first such discoveries in this country were made by Sumner, Louderback, Schmitt and Johnston (1914) in San Francisco Bay. They used Negetti-Zambta reversing thermometers for temperature and silver nitrate titration for salinity determination. These were by then considered to be classical methods and had been worked out in northern Europe, mostly in Scandinavia. They were introduced to the United States Gulf Coast …

Effects Of Saltwater Intrusion From The Inner Harbor Navigation Canal On The Benthos Of Lake Pontchartrain, Louisiana, Jane A. Junot, Michael A. Poirrier, Thomas M. Soniat

Gulf and Caribbean Research

A study of the benthos of southern Lake Pontchartrain, Louisiana, was conducted from July 1976 to July 1978. Seven offshore stations and three stations in the New Orleans Marina complex were sampled seasonally. Offshore stations formed a transect from the Lake Pontchartrain Causeway to the Inner Harbor Navigation Canal (I.H.N.C.). A west to east gradient of increasing salinity and salinity stratification was evident.

Faunal differences among stations were assessed using indices of diversity, biological dominance, pollution, and station homogeneity. The fauna of the marina stations had a low species diversity and was dominated by annelids, indicative of a stressed environment. …

Occurrence And Seasonality Of Perkinsus Marinus (Protozoa: Apicomplexa) In Mississippi Oysters, John Ogle, Katherine Flurry

Gulf and Caribbean Research

Oysters from four reefs in Mississippi Sound, sampled over a period of 25 months, were found to have a low prevalence of the protozoan parasite Perkinsus marinus. The greatest values were 80% prevalence, and 0.88 weighted incidence recorded for oysters from Biloxi Bay, Mississippi.

A Partial Bibliography Of Cyprinodon Variegatus (Osteichthyes: Cyprinodontidae), David A. Bengtson

Gulf and Caribbean Research

A partial bibliography of the sheepshead minnow Cyprinodon variegatus Lacépède, 1803, is presented. Scientific works related to systematics and general biology are listed along with references to recent work involving toxicological bioassays. An extensive search of the literature on parasites of C. variegatus was not conducted.

Macrobenthos Of Simmons Bayou And An Adjoining Residential Canal, James T. Mcbee, Walter T. Brehm

Gulf and Caribbean Research

Species composition, abundance and seasonal variations of benthic macroinvertebrates in Simmons Bayou, Mississippi, and an adjoining dead-end canal were investigated from July 1976 through June 1977. Cluster analysis of the data summed over five stations indicated four major time periods: July, August-November, December-February, and March-June. Polychaetes and oligochaetes were most abundant in the winter and spring, amphipods in the summer, and chironomids in the spring. Temporal changes in abundance of polychaetes, oligochaetes, and chironomids appeared to reflect seasonal reproductive cycles. The peak in amphipod density corresponded with dense growths of Ruppia maritima. Within the dead-end canal, poor water quality …

Notes On The Genus Probythinella Thiele, 1928 (Gastropoda: Hydrobiidae) In The Coastal Waters Of The Northern Gulf Of Mexico And The Taxonomic Status Of Vioscalba Louisianae Morrison, 1965, Richard W. Heard

Gulf and Caribbean Research

The gastropod genus Probythinella Thiele, 1928, is considered a senior synonym of Vioscalba Morrison, 1965. Probythinella louisianae (Morrison, 1965) n. comb. tentatively is recognized as a valid species distinct from the closely related P. lacustris (Baker, 1928) and P. protera Pilsbry, 1953. The eastern range of P. louisianae is extended to Mobile Bay, Alabama. Limited observations on the habitat and reproduction of P. louisianae are reported.

Effects Of 1973 Floodwaters On Plankton Populations In Louisiana And Mississippi, Suzanne R. Hawes, Harriet M. Perry

Gulf and Caribbean Research

Studies to assess the impact of floodwater diversion on plankton populations in coastal waters of Mississippi and Louisiana were conducted from 23 April 1973 through 13 July 1973. Fixed stations in Lake Pontchartrain, Lake Borgne and western Mississippi Sound were sampled once in April, twice in May and June, and once in July. Stations in Terrebonne Parish, Louisiana were visited once in May, June and July.

Data are presented on changes in the species composition of zooplankton subsequent to the opening of the Bonnet Card and Morganza floodways. The hydrographic conditions at the time of sampling are discussed.

The Effect Of Depth On Survival And Growth Of Oysters In Suspension Culture From A Petroleum Platform Off The Texas Coast, John Ogle, Sammy M. Ray, W.J. Wardle

Gulf and Caribbean Research

The effect of depth on oysters in suspension culture from a petroleum platform off the Texas coast was monitored for 20 months. Growth and condition was similar for adult oysters cultured at five levels down to 8 m. Oysters had a growth rate of 1.2 mm (level 3) to 1.4 mm (level 1) per month,representing an increase in length of 94% to 150% for the 20 months. The condition was best in June 1973 after five months placement offshore (condition index of 14.8, 15.5, 14.7, 13.5 and 13.2 for levels 1 through 5, respectively). The condition was lowest in June …

Some Effects Of Hurricanes On The Terrestrial Biota, With Special Reference To Camille, Gordon Gunter, Lionel N. Eleuterius

Gulf and Caribbean Research

There have been very few articles concerning the effects of hurricanes upon marine and shore organisms. Some effects on fishes have been described by Hubbs (1962) and in that paper he reviewed some of the previous references.

Information on animals killed or injured by hurricanes is scarce because potential observers in areas where they strike are generally more concerned with practical personal matters than biological studies right after a bad storm. The senior author has been in or very close to seven West India hurricanes as they came ashore. Each time he was somewhat forewarned and had determined to make …

A Supplement To The Fauna And Flora Of Horn Island, Mississippi, E. Avery Richmond

Gulf and Caribbean Research

Since the publication of “The Fauna and Flora of Horn Island, Mississippi’’ (Richmond 1962) search for unrecorded species present on this island, or in the waters surrounding it, has been continuing by myself and others. The premise that all of the plants and animals living in a given area can never be located completely is naturally well-founded. However, it seems advisable to continue the search for unlisted species of Horn Island.

Many unrecorded specimens have been collected and it seems proper at this time to make a supplementary list available to the public, particularly those interested in fields of science …

Oyster Abundance In Apalachicola Bay, Florida In Relation To Biotic Associations Influenced By Salinity And Other Factors, R.W. Menzel, N.C. Hulings, R.R. Hathaway

Gulf and Caribbean Research

From June 1955 through May 1957, stations on three oyster reefs were sampled quantitatively at intervals and all oysters and associated macroscopic organisms were recorded per unit area. Station I was a privately leased “natural” reef, consisting of higher places exposed at low water, with a salinity range of 22.7-36.6 o/oo and was fairly productive. Station II, depth ca. two meters, was the least saline, range 1.2-29.3 o/oo, and was considered very productive for natural reef. Station III, depth one meter, salinity range 7.5-35.7 o/oo, was depleted although there was an abundant spatfall.

Depth and bottom types as well as …

A Seasonal Ecological Study Of Foraminifera From Timbalier Bay, Louisiana, Robert P. Waldron

Gulf and Caribbean Research

This study concerns the ecological habits of living Foraminifera from a shallow Louisiana coastal bay during a period of ten months. It is a part of an extensive study undertaken by the Coastal Studies Institute of Louisiana State University to determine the effect of chemical and physical properties of water upon marine life in a large, open bay over an extended period of time. Samples were collected monthly from established locations for the chemical, biological and foraminiferal determinations. Results of the chemical and biological studies will be published by the respective investigators in subsequent papers.

The period of time covered …

Biological Investigations Of The St. Lucie Estuary (Florida) In Connection With Lake Okeechobee Discharges Through The St. Lucie Canal, Gordon Gunter, Gordon E. Hall

Gulf and Caribbean Research

A survey of the turbidity, salinity and sediment effects of St. Lucie Canal discharge into the St. Lucie Estuary was authorized by the Chief of Engineers on May 9, 1955. Expansion of that program to include the work of the present biological investigation was authorized by the Chief of Engineers on June 12, 1956.

The scope and purpose of this biological work was to: (a) review the history of the St. Lucie Canal and analyze the problems concerned with discharges of fresh water into the St. Lucie Estuary: (b) present biological data from a 2-year investigation of estuarine conditions, January …