179 resultados para Ships -- Ontario -- Niagara Peninsula -- History.
em Aquatic Commons
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The morphometric and morphological characters of the rostrum have been widely used to identify penaeid shrimp species (Heales et al., 1985; Dall et al., 1990; Pendrey et al., 1999). In this setting, one of the constraints in studies of penaeid shrimp populations has been the uncertainty in the identification of early life history stages, especially in coastal nursery habitats, where recruits and juveniles dominate the population (Dall et al., 1990; Pérez-Castañeda and Defeo, 2001). In the western Atlantic Ocean, Pérez-Farfante (1969, 1970, 1971a) described diagnostic characters of the genus Farfantepenaeus that allowed identification of individuals in the range of 8−20 mm CL (carapace length) on the basis of the following morphological features: 1) changes in the structure of the petasma and thelycum; 2) absence or presence of distomarginal spines in the ventral costa of the petasma; 3) the ratio between the keel height and the sulcus width of the sixth abdominal somite; 4) the shape and position of the rostrum with respect to the segments and flagellum of the antennule; and 5) the ratio between rostrum length (RL) and carapace length (RL/CL). In addition, she classified Farfantepenaeus into two groups according to the shape and position of the rostrum with respect to the segments and flagellum of the antennule and the ratio RL/CL: 1) F. duorarum and F. notialis: short rostrum, straight distally, and the proximodorsal margin convex, usually extending anteriorly to the end of distal antennular segment, sometimes reaching to proximal one-fourth of broadened portion of lateral antennular flagellum, with RL/CL <0.75; and 2) F. aztecus, F. brasiliensis, F. paulensis, and F. subtilis: long rostrum, usually almost straight along the entire length, extending anteriorly beyond the distal antennular segment, sometimes reaching to the distal one-third of broadened portion of lateral antennular flagellum, with RL/CL >0.80. Pérez-Farfante stressed that, for the recognition to species level of juveniles <10 mm CL, all the characters listed above should be considered because occasionally one alone may not prove to be diagnostic. However, the only characters that could be distinguished for small juveniles in the range 4−8 mm CL are those defined on the rostrum. Therefore, it has been almost impossible to identify and separate small specimens of Farfantepenaeus (Pérez-Farfante, 1970, 1971a; Pérez-Farfante and Kensley, 1997).
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(1 poster)
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The paper presents: 1) biologic summaries for each of the formations for which paleontologic data are available, with brief discussions of the geologic age; 2) geologic correlations of the formations and the distribution of their age-equivalents in Central America, the West Indies, and the southeastern United States; 3) an outline of the paleogeography of middle America. The biologic summaries are based on the paleontologic memoirs in this vol. by Messars. Howe, Berry, Chuchman, Jackson, Canu and Bassler and Pilsbry, Miss Rathbun and myself.
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(PDF contains 15 pages)
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This report presents information on the life history, diet, abundance and distribution, and length-frequency distributions of five invertebrates in Florida Bay, Everglades National Park. Collections were made with an otter trawl in basins on a bi-monthly basis. Non-parametric statistics were used to test spatial and temporal differences in the abundance of invertebrates when numbers were appropriate (i. e., $25). Invertebrate species are presented in four sections. The sections on Life History, and Diet were derived from the literature. The section on Abundance and Distribution consists of data from otter-trawl collections. In addition, comparisons with other studies are included here following our results. The section on Length-frequency Distributions consists of length measurements from all collections, except 1984-1985 when no measurements were taken. Length-frequency distributions were used, when possible, to estimate life stage captured, spawning times, recruitment into Florida Bay for those species which spawn outside the Bay, and growth. Additional material from the literature was added when appropriate. (PDF contains 39 pages)
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The family Priacanthidae contains four genera and four species that occur in the western central North Atlantic (Starnes, 1988). Pristigenys alta is distributed in the Caribbean, Gulf of Mexico and along the east coast of North America. Although juveniles have been reported from as far north as southern New England waters, adults are not reported north of Cape Hatteras, NC. Priacanthus arenatus is distributed in tropical and tropically influenced areas of the western central North Atlantic in insular and continental shelf waters. Adult P. arenatus are distributed north to North Carolina and Bermuda, juveniles have been collected as far north as Nova Scotia. Cookeolus japonicus and Heteropriacanthus cruentatus are circumglobally distributed species and are both common in insular habitats. In the western central North Atlantic, C. japonicus ranges from New Jersey to Argentina; H. cruentatus from New Jersey and northern Gulf of Mexico to southern Brazil (Starnes, 1988). (PDF contains 6 pages)
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The family Gerreidae contains four genera and 13 species that occur in the western central North Atlantic. Adult gerreids are small to medium size fishes that are abundant in coastal waters, bays, and estuaries in tropical and warm temperate regions and sometimes occur in freshwaters. They are generally associate~ with grassy or open bottoms, but not with reefs. Gerreids are silvery fishes, with deeply forked tails, and extremely protrusible mouth that points downward when protracted. They apparently feed on bottom-dwelling organisms and at least one species (Eucinostomus gula) shows a distinct transition, during the juvenile period, from a planktivore (exclusively copepods) to a carnivore that includes a diet of almost solely polychaetes (Carr & Adams, 1973; Robins and Ray, 1987; Murdy et al., 1997). (PDF contains 10 pages)
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Callionymidae, along with the Draconettidae and Gobiesocidae, previously were placed in the order Gobiesociformes (Allen, 1984). Recently, Nelson (1994) placed the Callionymidae and Draconettidae in the percifonn suborder Callionymoidei. The family is represented by three species in the western central North Atlantic Ocean, Diplogrammus pauciradiatus, Paradiplogrammus bairdi and Foetorepus agassizi (Davis, 1966; Robins and Ray, 1986). A detailed review ofthe family including early life history infonnation is given by Houde (1984) and Watson (1996). (PDF contains 11 pages)
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ENGLISH: The egg of the anchoveta, Cetengraulis mysticetus (Günther), was identified in the Gulf of Panama by its size, difference in diurnal period of spawning, seasonal occurrence (October to January) and relative abundance. It is pelagic, translucent and oval with mean dimensions of 1.166 mm. and 0.558 mm. for the long and short axes respectively. The egg membrane is unsculptured, the yolk mass is markedly segmented, and no oil globule or pigmentation is present. It was not found in the plankton from mid-January 1957 until the latter part of the following September; during this period the gonads of the anchoveta were immature. Only one other anchovy egg, spawned during the same diurnal period, is sufficiently similar in dimensions to be confused with that of the anchoveta; however, it is slightly smaller. SPANISH: El huevo de la anchoveta, Cetengraulis mysticetus (Günther), fué identificado en el Golfo de Panamá por su tamaño, diferencias en el período diario de desove, su abundancia en la temporada (de octubre a enero) y por su abundancia relativa. El huevo es pelágico, translúcido, oval y con dimensiones promedio de 1.166 mm. y 0.558 mm. para los ejes largo y corto, respectivamente. La membrana es lisa, el vitelo está francamente segmentado y no posee ningún glóbulo graso o pigmentación. El huevo de la anchoveta no se encontró en el plancton en el período comprendido entre mediados de enero y fines de septiembre de 1957; durante este lapso las gónadas estuvieron inactivas.
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Whenever human beings have looked out on the sea, they have seen whales. First from the shore and later from ships when humanity entered the ocean realm as seafarers, we have responded to seeing these creatures with awe and wonder. Even when we hunted whales, a period well chronicled both in history and in literature, the sight of a whale brought an adrenaline rush that was not totally linked to potential economic gain. The first trips on boats specifically to watch, rather than hunt, whales began around 45 years ago in Southern California where the migrating gray whales, seen in the distance from land, drew vessels out for a closer look. Since that time whalewatching has boomed, currently conducted in over 40 countries around the world, including Antarctica, and estimated by economists at the Whale and Dolphin Conservation Society to have a 1999 worldwide economic value of around $800 million USD. The economic contribution to local coastal communities is particularly significant in developing countries and those where declining fish populations (and in some cases like the Japanese, international bans on whaling) have driven harvesters to look for viable alternatives. Clearly, whalewatching is now, in many places around the world, a small but thriving part of the regional economy. Like in the days of whaling, we still get the rush, but for some, money is back contributing to the physiological response. (PDF contains 90 pages.)
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Arrowtooth flounder (Atheresthes stomias) has the highest biomass of any groundfish species in the Gulf of Alaska, is a voracious predator of age 1 walleye pollock (Theragra chalcogramma), and is a major component in the diet of Steller sea lions (Eumetopias jubatus). Owing to its ecological importance in the Gulf of Alaska and the limited information available on its reproduction, interest has intensified in describing its spawning and early life history. A study was undertaken in late January–February 2001–2003 in the Gulf of Alaska to obtain information on adult spawning location, depth distribution, and sexual maturity, and to obtain fertilized eggs for laboratory studies. Adults were found 200–600 m deep east of Kodiak Island over the outer continental shelf and upper slope, and southwest along the shelf break to the Shumagin Islands. Most ripe females (oocytes extruded with light pressure) were found at 400 m and most ripe males (milt extruded with light pressure) were found at depths ≥450 m. Eggs were fertilized and incubated in the laboratory at 3.0°, 4.5°, and 6.0°C. Eggs were reared to hatching, but larvae did not survive long enough to complete yolk absorption and develop pigment. Eggs were staged according to morphological hallmarks and incubation data were used to produce a stage duration table and a regression model to estimate egg age based on water temperature and developmental stage. Arrowtooth flounder eggs (1.58–1.98 mm in diameter) were collected in ichthyoplankton surveys along the continental shelf edge, primarily at depths ≥400 m. Early-stage eggs were found in tows that sampled to depths of ≥450 m. Larvae, which hatch between 3.9 and 4.8 mm standard length, increased in abundance with depth. Observations on arrowtooth flounder eggs and early-stage larvae were used to complete the description of the published partial developmental series.(PDF file contains 34 pages.)
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ENGLISH: Howard and Landa (1958) and Barrett and Howard (1961) have studied the life history of the anchoveta in most of the areas where this species occurs in important quantities. The Gulf of Panama was the only area of Panama included in these studies, as this was the only one from which sufficient samples were available. Berdegue (1958) compared certain meristic and morphometric characters of anchovetas from Montijo Bay and nine other areas of the eastern tropical Pacific Ocean. He found statistically significant differences, and concluded that the fish of the different areas belonged to separate "populations." Fish from Chiriquí province were not included in his study. Since the, completion of the above-mentioned studies, a number of collections of anchovetas from Montijo Bay and Chiriquí province have been obtained. In the present report use is made of this material to determine the salient facts regarding the life history of the anchoveta from these areas and to supplement the available knowledge of the identity of the intraspecific groups. Acknowledgment is extended to Dr. Milner B. Schaefer, formerly Director of Investigations, Inter-American Tropical Tuna Commission (now Director, Institute of Marble Resources, University of California), Mr. Clifford L. Peterson, Assistant Director of Investigations, and Mr. Edward F. Klima (now with the U. S. Bureau of Commercial Fisheries) for advice and assistance rendered to the project. The shrimp-boat samples were collected by Captains Robert Barrett, Stephen Barrett, and Chester McLean. SPANISH: Howard y Landa (1958) y Barrett y Howard (1961) han estudiado la historia natural de la anchoveta en la mayoría de las áreas en donde esta especie aparece en cantidades importantes. El Golfo de Panamá es la única area de Panamá incluida en estos estudios, ya que es la única de la cual hubo suficientes muestras disponibles. Berdegué (1958) camparó ciertos caracteres merístieos y morfométricos de la anehoveta del Golfo de Montijo y otras nueve áreas del Océano Pacífico Oriental Tropical. Encontró diferencias estadísticamente significativas e hizo la conclusión de que los peces de las diferentes áreas pertenecían a "poblaciones" separadas. Los peces de la Provincia de Chiriquí no fueron incluidos en su estudio. Desde la terminación de los estudios antes meneionados se obtuvieron varias recolecciones de anchovetas del Golfo de Montijo y de la Provincia de Chiriquí. En el presente informe se usó este material para determinar los hechos sobresalientes referentes a la historia natural de la anchoveta de estas áreas y suplir el conocimiento disponible de la identidadde los grupos intraespecíficos. Se hace extensivo un reconocimiento al Dr. Milner B. Schaefer, antiguo director de investigaciones de la Comisión Interamericana del Atún Tropical (ahora director del Institute of Marine Resources, University of California), al Sr. Clifford L. Peterson, asistente del director de investigaciones, y al Sr. Edward F. Klima (ahora can el U. S. Bureau of Commercial Fisheries) por su consejo y ayuda prestados en este proyecto. Las muestras de los barcos camaroneros fueron reeolectadas por los capitanes Robert Barrett, Stephen Barrett y Chester McLean
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There are 19 economically important reef fish species in the deepwater (l00-300 m) fishery of the southeastern United States. Five species make up the majority (over 97% by weight) of the catch. In descending order of total landings for 1995, they are: tilefish, Lopholatilus chamaeleonticeps, snowy grouper, Epinephelus niveatus, blueline tilefish, Caulolatilus microps, warsaw grouper, Epinephelus nigritus, and yellowedge grouper, E. flavolimbatus. Life history summaries and estimates of catches from 1972 through 1995 for 14 species are described. (PDF file contains 45 pages.)
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(PDF file contains 248 pages.)