Life Sciences Commons^™

Notes On Barnacles (Cirripedia: Thoracica) From The Gulf Of Mexico, Stephen R. Gittings

Gulf and Caribbean Research

Examination of several collections of barnacles from the northern and western Gulf of Mexico made over the last 30 years has improved our knowledge of the distributions of several taxa previously considered to be absent or rare in those regions. Conchoderma auritum (Linnaeus) and Heteralepas sp. aff. cornuta (Darwin) are recorded for the first time from the Gulf of Mexico. Conchoderma auritum, Conchoderma virgatum (Spengler), Heteralepas cornuta (Darwin), Balanus trigonus (Darwin), Balanus venustus Darwin, and Balanus amphitrite amphitrite Darwin have broad distributions outside the Gulf of Mexico. Tetraclita stalactifera stalactifera (Lamarck) is abundant in the intertidal zones of the …

Tanaidacea (Crustacea: Peracardia) Of The Gulf Of Mexico. Iv. On Nototanoides Trifurcatus Gen. Nov., Sp. Nov., With A Key To The Genera Of The Nototanaidae, Jurgen Sieg, Richard W. Heard

Gulf and Caribbean Research

Nototanoides trifurcatus gen. nov., sp. nov. is described and illustrated from the Gulf of Mexico. Nototanoides differs from the other genera of the family by the male possessing a vestigial maxilliped. It most closely resembles the genera Nototanais and Androtanais. In addition to the differences of the maxillipeds the males of Nototanoides can be separated by the 4-segmented antenna 1 and the females are distinguished by the trifurcate spine on the second segment of the palp of the maxilliped. A key to known genera of the family Nototanaidae is presented.

Testis-Ova In Spawning Blue Tilapia, Oreochromis Aureus, B. Clark, H.J. Grier

Gulf and Caribbean Research

Hermaphroditism characterized by the presence of oocytes in the testes is described in the blue tilapia, Oreochromis aureus, for the first time. Testis-ova were observed in three of 24 spawning males exhibiting otherwise normal male morphology. The testis-ova appeared non-vitellogenic and lacked a follicle cell layer. It is speculated that the testis-ova did not become vitellogenic due to their association with Sertoli cells and the hormonal environment of the male.

Soil Characteristics Of Four Juncus Roemerianus Populations In Mississippi, Lionel N. Eleuterius, John D. Caldwell

Gulf and Caribbean Research

The physical and chemical characteristics of soil from four widely separated Juncus roemerianus populations in Mississippi tidal marshes are determined. The J. roemerianus populations studied are located in Grand Bayou, Salt Flats, Weeks Bayou,and Belle Fantaine marshes. Organic matter, pH, CEC, N, P, K, Ca, S, Mg, and Zn analyses are based on composite soil samples. The percentage of sand, silt, and clay of the marsh soils is determined along with soil water content from the four locations. Statistical analysis indicates which marshes are different for each soil characteristic tested. No appreciable amounts of organic matter are present in the …

Metabolic Activity Of The Epiphytic Community Associated With Spartina Alterniflora, Wilmer C. Stowe, James G. Gosselink

Gulf and Caribbean Research

Primary production and respiration rates were determined for two epiphytic communities associated with Spartina alternifloraLoisel., in the southwestern Barataria Bay area of Louisiana. The communities studied were: (1) a shoreline community and (2) a community 1.5 meters inland from the shoreline site. Annual mean net production and respiration rates for the shoreline community were 25.8 and -19.6 mg C • (m² substrate area)^-1 • h^-1 respectively;whereas the inland community showed corresponding rates of -3.3 and -12.5 mg C • (m² substrate area)^-1 • h^-1, respectively. Thus, the shoreline community was a net …

A Survey Of Population Characteristics For Red Drum And Spotted Seatrout In Louisiana, John M. Wakeman, Paul R. Ramsey

Gulf and Caribbean Research

Red drum and spatted seatrout stocks were sampled from seven separate study areas along the Louisiana coast and from one estuarine area in Texas, with additional intensive temporal (monthly) and microgeographic (range of salinity regimes) samplings being carried out in one Louisiana study area. Condition coefficients, which did not appear to be affected by salinity regimes within the microgeographic sampling area, varied significantly according to study area, with Texas fish showing significantly lower condition coefficients than Louisiana fish. Van Bertalanffy growth equations were fitted and annual mortality rates were estimated to obtain preliminary estimates of yields, population numbers, and densities …

Spatial Influences On Temporal Variations In Leaf Growth And Chemical Composition Of Thalassia Testudinum Banks Ex König In Tampa Bay, Florida, Michael J. Durako, Mark D. Moffler

Gulf and Caribbean Research

The importance of spatial influences on seasonal fluctuations in Thalassia testudinum leaf blade lengths and chemical constituents was demonstrated. Differences between samples from fringe and mid-bed for several constituents were significant and, if not accounted for, could affect the measurement of apparent seasonal cycles. Fringe-shoots, reflecting the influence of more intense grazing activity, had shorter leaf blade lengths, lower dry weights and carbohydrate levels, and higher protein levels than mid-bed shoots. Mid-bed rhizomes and roots had highest protein and ash levels reflecting possible sediment influence. Percent ash and protein in the rhizomes, and percent carbohydrate in the roots exhibited seasonal …

Yield-Per-Recruit Of Spotted Seatrout, Richard E. Condrey, Gerald Adkins, Michael W. Wascom

Gulf and Caribbean Research

A von Bertalanffy growth curve,

L = 65.47 cm (1 - e^{-.2005 (t + .4113 yr)}),

is derived from published data on spotted seatrout in the U.S. Gulf of Mexico and used in constructing a yield-per-recruit contour. Maximum yield-per-recruit is approached as F increases above 1 and age of first entry approaches 3.9 years (14.9 in., 1.1 lb). A linear regression is derived relating average size of capture to gill net mesh size (MS in inches),

L = 1.97 in. + 8.63 MS,

and used along with legal sizes of first harvest to evaluate the impact of current …

Soil Characteristics Of Spartina Alterniflora, Spartina Patens, Juncus Roemerianus, Scirpus Olneyi, And Distichlis Spicata Populations At One Locality In Mississippi, Lionel N. Eleuterius, John D. Caldwell

Gulf and Caribbean Research

Soil characteristics from five adjacent monotypic zones or different populations of tidal marsh plants are determined. Populations of Spartina alterniflora, Spartina patens, Juncus roemerianus, Scirpus olneyi, and Distichlis spicata located in Graveline Bay marsh, Mississippi, are studied. Slight elevational differences between the plant populations exist. The aerial biomass for each plant population is different based on seasonal determinations. Soil pH, organic matter, N, P, K, S, Zn, Ca, and Mg concentrations are based on analyses of seasonal composite soil samples. Analyses of soil water samples are used to determine water content, salinity, PO₄, and …

The Effects Of Weathered Crude Oil From The M/T Alvenus Spill On Eggs And Yolk-Sac Larvae Of Red Drum (Sciaenops Ocellatus), George J. Guillen, Dennis Palafox

Gulf and Caribbean Research

The Biitish tanker M/T ALVENUS ran aground 16.1 km south of Cameron, Louisiana, on 30 July 1984. An estimated 10,157 MT of Venezuelan crude oil were spilled into the Gulf of Mexico. Approximately 2,700 MT of the heavy viscous oil impacted beaches and an additional 1,360 MT remained in the subtidal areas of west Galveston Island, about 160 km southwest of the accident site. Red drum, which spawn in the Gulf of Mexico in the fall, could have been seriously impacted by oil concentrations potentially lethal to eggs or larvae. The impact of weathered crude oil on the survival, growth, …