Résultats 1-20 de 157

    • Synopsis of biological data on the blue crab, Callinectes sapidus Rathbun

      Millikin, Mark R.; Williams, Austin B. (NOAA/National Marine Fisheries Service, 1984)
      This synopsis reviews taxonomy, morphology, distribution, life history, commercial hard and soft shell crab fisheries, physiology, diseases, ecology, laboratory culture methodology, and influences of environmentalpollutants on the blue crab, Callinecles sapidus. Over 300 selected, published reports up to and including 1982are covered. (PDF file contains 45 pages.)
    • Development of hexagrammids (Pisces: Scorpaeniformes) in the northeastern Pacific Ocean

      Kendall, Jr. , Arthur W.; Vinter, Beverly (NOAA/National Marine Fisheries Service, 1984)
      Larvae of Oxylebius pictus, Zaniolepis sp., Ophiodon elongatus, Hexagrommos stelleri, H. decagrammus, H.lagocephalus, H. octogrammus, and Pleurogrammus monopterygius are described and illustrated from field collections which were supplemented by laboratory reared specimens of some species. Larvae hatch at a rather large size (3-9 mm), are heavily pigmented, and undergo direct development to an epipelagic prejuvenile stage. Larvae or the five genera are separable on the basis of body shape, pigmentation, and meristic characters. Larvae or the four species of Hexagrammos, which are quite similar in appearance, are separable on the basis of a combination of several pigmentation characters. Developmental evidence indicates that Oxylebius and Zaniolepis are similar to each other and are more similar to presumed primitive coUids than the other included genera. Ophiodon is dissimilar to the other four genera. Pleurogrammus and Hexagrommos have similar appearing larvae. Among the species of Hexagrammosa progression or increasing larval pigmentation can be seen from H. stelleri to H. decagrammus, H. lagocephalus, and H. octogrammus. (PDF file contains 50 pages.)
    • Configurations and relative efficiencies of shrimp trawls employed in southeastern United States waters

      Watson, Jr., John W.; Workman, Ian K.; Taylor, Charles W.; Serra, Anthony F. (NOAA/National Marine Fisheries Service, 1984)
      Common shrimp trawl designs employed in the southeastern United States shrimp fishery are the flat, balloon, semiballoon, jib, and super X-3. Recent innovations in trawl design and rigging, including the twin trawl rigging and tongue trawl design, have improved the efficiency of shrimp trawling gear. A description of the construction techniques for the different designs indicate differences which affect gear performance. Measurements of horizontal spread and vertical opening for 76 trawl configurations indicate the relative efficiencies of the different designs. Maximum horizontal spreading efficiency was achieved by the "twin" and "tongue" trawl designs followed by the super X-3, jib, balloon, and semiballoon designs. Designs having the greatest vertical openings were the tongue and flat trawl designs followed by the semiballoon. Maximum total gape dimension was demonstrated by the "Mongoose" tongue trawl. Comparison of trawl spreading efficiency and door area to headrope length ratio indicates that a range of 70-80 in square (per door) of door area is required for each foot of trawl headrope length for maximum efficiency with conventional trawl designs and 66-75 in square per foot of headrope for tongue trawl designs. (PDF file contains 18 pages.)
    • Management of northern fur seals on the Pribilof Islands, Alaska, 1786-1981

      Roppel, Alton Y. (NOAA/National Marine Fisheries Service, 1984)
      This paper includes information about the Pribilof Islands since their discovery by Russia in 1786 and the population of northern fur seals, Cailorhinus ursinus, that return there each summer to bear young and to breed. Russia exterminated the native population of sea Oilers, Enhydra lulris, here and nearly subjected the northern fur seal to the same fate before providing proper protection. The northern fur seal was twice more exposed to extinctionfollowing the purchase of Alaska and the Pribilof Islands by the United States in 1867. Excessive harvesting wasstopped as a result of strict management by the United States of the animals while on land and a treaty betweenJapan, Russia, Great Britain (for Canada), and the United States that provided needed protection at sea. In 1941,Japan abrogated this treaty which was replaced by a provisional agreement between Canada and the United Statesthat protected the fur seals in the eastern North Pacific Ocean. Japan, the U.S.S.R., Canada, and the United Statesagain insured the survival of these animals with ratification in 1957 of the "Interim Convention on the Conservation of North Pacific Fur Seals," which is still in force. Under the auspices of this Convention, the United States launched an unprecedented manipulation of the resource through controlled removal during 1956-68 of over 300,000 females considered surplus. The biological rationale for the reduction was that production of fewer pups would result in a higher pregnancy rate and increased survival, which would, in turn, produce a sustained annual harvest of 55,000-60,000 males and 10,000-30,000 females.Predicted results did not occur. The herd reduction program instead coincided with the beginning of a decline in the number of males available for harvest. Suspected but unproven causes were changes in the toll normally accounted for by predation, disease, adverse weather, and hookworms. Depletion of the animals' food supply by foreign fishing Heets and the entanglement of fur seals in trawl webbing and other debris discarded at sea became a prime suspect in altering the average annual harvest of males on the Pribilof Islands from 71,500 (1940-56) to 40,000 (1957-59) to 36,000 (1960) to 82,000 (1961) and to 27,347 (1972-81). Thus was born the concept of a research control area for fur seals, which was agreed upon by members of the Convention in 1973 and instituted by the United Stateson St. George Island beginning in 1974. All commercial harvesting of fur seals was stopped on St. George Islandand intensive behavioral studies were begun on the now unharvested population as it responds to the moratoriumand attempts to reach its natural ceiling. The results of these and other studies here and on St. Paul Island areexpected to eventually permit a comparison between the dynamics of unharvested and harvested populations, which should in turn permit more precise management of fur seals as nations continue to exploit the marine resources of the North Pacific Ocean and Bering Sea. (PDF file contains 32 pages.)
    • Net phytoplankton and zooplankton in the New York Bight, January 1976 to February 1978, with comments on the effects of wind, Gulf Stream eddies, and slope water intrusions

      Smith, Daniel E.; Jossi, Jack W. (NOAA/National Marine Fisheries Service, 1984)
      Results are given of monthly net phytoplankton and zooplankton sampling from a 10 m depth in shelf, slope, and Gulf Stream eddy water along a transect running southeastward from Ambrose Light, New York, in 1976, 1977, and early 1978. Plankton abundance and temperature at 10 m and sea surface salinity at each station are listed. The effects of atmospheric forcing and Gulf Stream eddies on plankton distribution and abundance arc discussed. The frequency of Gulf Stream eddy passage through the New York Bight corresponded with the frequency of tropical-subtropical net phytoplankton in the samples. Gulf Stream eddies injected tropical-subtropical zooplankton onto the shelf and removed shelfwater and its entrained zooplankton.Wind-induced offshore Ekman transport corresponded generally with the unusual timing of two net phytoplanktonmaxima. Midsummer net phytoplankton maxima were recorded following the passage of Hurricane Belle (August 1976) and a cold front (July 1977). Tropical-subtropical zooplankton which had been injected onto the outer shelf by Gulf Stream eddies were moved to the inner shelf by a wind-induced current moving up the Hudson Shelf Valley. (PDF file contains 47 pages.)
    • Ichthyoplankton survey of the estuarine and inshore waters of the Florida Everglades, May 1971 to February 1972

      Collins, L Alan; Finucane, John H. (NOAA/National Marine Fisheries Service, 1984)
      Quarterly ichthyoplankton sampling was conducted at 16 estuarine and 24 inshore stations along the FloridaEverglades from May 1971 to February 1972. The area is one of the most pristine along lhe Florida coast. Thesurvey provided the first comprehensive information on seasonal occurrence, abundance (under 10 m' of surfacearea), and distribution of fish eggs and larvae in this area. A total of 209,462 fish eggs and 78,865 larvae wascollected. Eggs were identified only as fish eggs, but among the larvae, 37 families, 47 genera, and 37 specieswere identified. Abundance of eggs and larvae, and diversity of larvae, were greatest in the inshore zone. The 10 most abundant fish families which together made up 90.7% of all larvae from the study area were, in descendingorder of abundance: Clupeidae, Engraulidae, Gobiidae, Sciaenidae, Carangidae, Pomadasyidae, Cynoglossidae,Gerreidae, Triglidae, and Soleidae. Clupeidae, Engraulidae, and Gobiidae made up 59.9% of all larvae. The inshore zone (to a depth of about 10 m) was a spawning ground and nursery for many fishes important to fisheries. The catch of small larvae (<>3.5 mm SL) indicated that most fishes identified from the 10 most abundant families spawned throughout the inshore zone at depths of <> 10 m, but Orthopristis chrysoptera, Gerreidae, and Prionotusspp. spawned at depths > 10 m, with offshore to inshore (eastward) larval transport. Salinity was one of severalenvironmental factors that probably limited the numbers of eggs and larvae in the estuarine zone. Abundance ofeggs and larvae at inshore stations was usually as great as, and sometimes greater than, the abundance of eggs and larvae at offshore stations (due west of the Everglades). (PDF file contains 81 pages.)
    • The feeding ecology of some zooplankters that are important prey items of larval fish

      Turner, Jefferson T. (NOAA/National Marine Fisheries Service, 1984)
      Diets of 76 species of fish larvae from most oceans of the world were inventoried on the basis of information in 40 published studies. Although certaln geographlc, size- and taxon-specific patterns were apparent, certain zooplankton taxa appeared in the diets of larvae of a variety of fish species in numerous localities. Included were six genera of calanoid copepods (Acartia, Calanus, Centropages, Paracalanus, Pseudocaianus, Temora), three genera of cyclopoid copepods (Corycaeus, Oilhona, Oncata), harpacticoid copepods, copepod nauplii, tintinoids,cladocerans of the genera Evadne and Podon, barnacle nauplii, gastropod larvae, pteropods of the genus Limacina, and appendicularians. Literature on feeding habits of these zooplankters reveals that most of the copepods are omnivorous, feeding upon both phytoplankton and other zooplankton. Some taxa, such as Calanus, Paracalanus, Pseudocalanus, and copepod nauplii appear to be primarily herbivorous, while others, such as Acartia, Centropages, Temora, and cyclopoids exhibit broad omnivory or carnivory. The noncopepod zooplankters are primarily filter-feeders upon pbytoplankton and/or bacterioplankton. Despite the importance of zooplankters in larval fish food webs, spectic knowledge of the feeding ecology of many taxa is poor. Further, much present knowledge comes only from laboratory investigations that may not accurately portray feeding habits of zooplankters in nature. Lack of knowledge of the feeding ecology of many abundant zooplankters,which are also important in larval fish food webs, precludes realistic understanding of pelagic ecosystemdynamics. (PDF file contains 34 pages.)
    • Proceedings of the International Workshop on age determination of oceanic pelagic fishes: Tunas, billfishes, and sharks, Miami, Florida, February 15-18,1982

      Prince, Eric D.; Pulos, Lynn M. (NOAA/National Marine Fisheries Service, 1983)
      Accurate and precise estimates of age and growth rates are essential parameters in understanding the population dynamics of fishes. Some of the more sophisticated stock assessment models, such as virtual population analysis, require age and growth information to partition catchdata by age. Stock assessment efforts by regulatory agencies are usually directed at specific fisherieswhich are being heavily exploited and are suspected of being overfished. Interest in stock assessment of some of the oceanic pelagic fishes (tunas, billfishes, and sharks) has developed only over the last decade, during which exploitation has increased steadily in response to increases in worldwide demand for these resources.Traditionally, estimating the age of fishes has been done by enumerating growth bands on skeletal hardparts, through length frequency analysis, tag and recapture studies, and raising fish in enclosures. However, problems related to determining the age of some of the oceanic pelagic fishesare unique compared with other species. For example, sampling is difficult for these large, highly mobile fishes because of their size, extensive distributions throughout the world's oceans, and for some, such as the marlins, infrequent catches. In addition, movements of oceanic pelagic fishes often transect temperate as well as tropical oceans, making interpretation of growth bands onskeletal hardparts more difficult than with more sedentary temperate species. Many oceanic pelagics are also long-lived, attaining ages in excess of 30 yr, and more often than not, their life cycles do not lend themselves easily to artificial propagation and culture. These factors contribute to the difficulty of determining ages and are generally characteristic of this group-the tunas, billfishes, and sharks. Accordingly, the rapidly growing international concern in managing oceanic pelagic fishes, as well as unique difficulties in ageing these species, prompted us to hold this workshop.Our two major objectives for this workshop are to: I) Encourage the interchange of ideas on this subject, and 2) establish the "state of the art." A total of 65 scientists from 10 states in the continental United States and Hawaii, three provinces in Canada, France, Republic of Senegal,Spain, Mexico, Ivory Coast, and New South Wales (Australia) attended the workshop held at the Southeast Fisheries Center, Miami, Fla., 15-18 February 1982.Our first objective, encouraging the interchange of ideas, is well illustrated in the summaries of the Round Table Discussions and in the Glossary, which defines terms used in this volume. The majority of the workshop participants agreed that the lack of validation of age estimates and themeans to accomplish the same are serious problems preventing advancements in assessing the age and growth of fishes, particularly oceanic pelagics. The alternatives relating to the validation problem were exhaustively reviewed during the Round Table Discussions and are a major highlight of this workshop. How well we accomplished our second objective, to establish the "state of the art" on age determination of oceanic pelagic fishes, will probably best be judged on the basis of these proceedings and whether future research efforts are directed at the problem areas we have identified.In order to produce high-quality papers, workshop participants served as referees for the manuscripts published in this volume. Several papers given orally at the workshop, and included in these proceedings, were summarized from full-length manuscripts, which have been submitted to or published in other scientific outlets-these papers are designated as SUMMARY PAPERS. In addition, the SUMMARY PAPER designation was also assigned to workshop papers that represented very preliminary or initial stages of research, cursory progress reports, papers that weredata shy, or provide only brief reviews on general topics. Bilingual abstracts were included for allpapers that required translation.We gratefully acknowledge the support of everyone involved in this workshop. Funding was provided by the Southeast Fisheries Center, and Jack C. Javech did the scientific illustrations appearing on the cover, between major sections, and in the Glossary. (PDF file contains 228 pages.)
    • Sampling statistics in the Atlantic menhaden fishery

      Chester, Alexander J. (NOAA/National Marine Fisheries Service, 1984)
      Atlantic menhaden, Brrvoortia tyrannus, the object of a major purse-seine fishery along the U.S. east coast,are landed at plants from northern Florida to central Maine. The National Marine Fisheries Service has sampledthese landings since 1955 for length, weight, and age. Together with records of landings at each plant, thesamples are used to estimate numbers of fish landed at each age. This report analyzes the sampling design in terms of probablity sampling theory. The design is c1assified as two-stage cluster sampling, the first stage consistingof purse-seine sets randomly selected from the population of all sets landed, and the second stage consistingof fish randomly selected from each sampled set. Implicit assumptions of this design are discussed with special attention to current sampling procedures. Methods are developed for estimating mean fish weight, numbers of fish landed, and age composition of the catch, with approximate 95% confidence intervals. Based on specific results from three ports (port Monmouth, N.J., Reedville, Va., and Beaufort, N.C.) for the 1979 fishing season, recommendations are made for improving sampling procedures to comply more exactly with assumptions of the sampling design. These recommendatlons include adopting more formal methods for randomizing set and fish selection, increasing the number of sets sampled, considering the bias introduced by unequal set sizes, and developing methods to optimize the use of funds and personnel. (PDF file contains 22 pages.)
    • Proceedings of the Seventh U.S.-Japan Meeting on Aquaculture, Marine Finfish Culture, Tokyo, Japan, October 3-4, 1978

      Sindermann, Carl J. (NOAA/National Marine Fisheries Service, 1984)
      The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the UnitedStates-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries.The UJNR was started by a proposal made during the Third Cabinet-Level Meeting of the Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. In addition to aquaculture, current subjects in the program are desalination of seawater, toxic microorganisms, air pollution, energy, forage crops, national park management, mycoplasmosis, wind and seismic effects, protein resources, forestry, and several joint panels and committees in marine resources research, development, and utilization.Accomplishments include: Increased communications and cooperation among technical specialists; exchanges of information, data, and research findings; annual meetings of the panels, a policy coordinative body;' administration staff meetings; exchanges of equipment, materials, and samples; several major technical conferences; and beneficial effects on international relations.(PDF file contains 37 pages.)
    • Taxonomy of North American fish Eimeriidae

      Upton, Steve J.; Reduker, David W.; Current, William L.; Duszynski, Donald W. (NOAA/National Marine Fisheries Service, 1984)
      Taxonomic descriptions, line drawings, and references are given for the 30 named and 5 unnamed species of North American fish Eimeriidae. In addition, a key was developed based on available morphologic data to distinguish between similar species. Taxa are divided into two genera: Eimeria (27 species) which are tetr&sporocystic with dizoic, nonbivalved sporocysts, and Goussia (3 species) which are tetrasporocystic with dizoic, bivalved sporocysts that lack Stleda bodies and have sporocyst walls composed of two longitudinal valves. (PDF file contains 24 pages.)
    • Soviet-American Cooperative Research on Marine Mammals. Volume 1- Pinnipeds: Under Project V.6. Marine Mammals, of the US-USSR Agreement on Cooperation in the Field of Environmental Protection

      Fay, Francis H.; Fedoseev, Gennadii A. (NOAA/National Marine Fisheries Service, 1984)
      Some 25 to 30 yr ago, when we as students were beginning our respective careers and were developing for the first time our awareness of marine mammals in the waters separating western North America from eastern Asia, we had visions of eventually bridging the communication gap which existed between our two countries at that time. Each of us was anxious to obtain information on the distribution,biology, and ecological relations of "our" seals and walruses on "the other side," beyond our respectivepolitical boundari~s where we were not permitted to go to study them. We were concerned that the resource management practices on the other side of the Bering and Chukchi Seas, implemented in isolation, on a purely unilateral basis, might endanger the species which we had come to know and were striving to conserve. At once apparent to both of us was the need for free exchange of biological information between our two countries and, ultimately, joint management of our shared resources. In a small way, we and others made some initial efforts to generate that exchange by personal correspondence and through vocal interchange at the annual meetings of the North Pacific Fur Seal Commission. By the enabling Agreement on Cooperation in the Field of Environmental Protection, reached between our two countries in 1972, our earlier visions at last came true. Since that time, within the framework of the Marine Mammal Project under Area V of that Agreement, we and our colleagues have forged a strong bond of professional accord and respect, in an atmosphere of free intercommunication and mutual understanding. The strength and utility of this arrangement from the beginning of our joint research are reflected in the reports contained in this, the first compendium of our work.The need for a series of such a compendia became apparent to us in 1976, and its implementation was agreed on by the regular meeting of the Project in La Jolla, Calif., in January 1977. Obviously, the preparation and publication of this first volume has been excessively delayed, in part by continuing political distrust between our governments but mainly by increasing demands placed on the time of thecontributors. In this period of growing environmental concern in both countries, we and our colleagues have been totally immersed in other tasks and have experienced great difficulty in drawing together the works presented here. Much of the support for doing so was provided by the State of Alaska, through funding for Organized Research at the University of Alaska-Fairbanks. For its ultimate completion in publishable form we wish to thank Helen Stockholm, Director of Publications, Institute of Marine Science, University of Alaska, and her staff, especially Ruth Hand, and the numerous referees narned herein who gave willingly oftheir time to review each ofthe manuscripts critically and to provide a high measure of professionalism to the final product. (PDF file contains 110 pages.)
    • Guidelines for reducing porpoise mortality in tuna purse seining

      Coe, James M.; Holts, David B.; Butler, Richard W. (NOAA/National Marine Fisheries Service, 1984)
      More than a decade has passed since the passage of the Marine Mammal Protection Act of 1972. During that time the U.S. tuna purse seine neet reduced its incidental porpoise mortality rate more than 10-fold. This was made possible through the development of gear and techniques aimed at reducing the frequency of many low probability events that contribute to the kill.Porpoise are killed by becoming entangled or entrapped in folds and canopies of the net and suffocating. The configuration of the net, both before and during the backdown release procedure, is a major determinant ofthe number of porpoise killed. Speedboats can be used to tow on the corkllne to prevent net collapse and also toadjust the net configuration to reduce net canopies prior to backdown. Deepening a net can reduce the probability of porpoise being killed by prebackdown net collapse. The effects of environmental conditions and mechanicalfailures on net configuration can result in high porpoise mortality unless mitigated by skilled vessel maneuvers orprevented by the timely use of speedboats to adjust the net.The backdown procedure is the only means to effectively release captured porpoise from a purse seine. It isalso the time during the set when most of the mortality occurs. The use of small mesh safety panels and aprons inthe backdown areas of nets reduces porpoise entanglement, and Increases the probability of an effective release.The tie-down points on the net for preparing the backdown channel must be properly located in order to optimize porpoise release. A formula uses the stretched depth of the net to calculate one of these points, making it a simple matter to locate the other. Understanding the dynamics of the backdown procedure permits a thorough troubleshooting of performance, thus preventing the repetition of poorly executed backdowns and thereby reducing mortality.Porpoise that cannot be released must be rescued by hand. A rescuer in a rigidly inflated raft can rescue porpoiseeffectively at any time during a net set. Hand rescue can make the difference between above average kill and zero kill sets. In all circumstances, the skill and motivation of the captain and his crew are the final determinants in the prevention of incidental porpoise mortality in tuna seining. (PDF file contains 22 pages.)
    • Synopsis of biological data on shortnose sturgeon, Acipenser brevirostrum LeSueur 1818

      Dadswell, Michael J.; Taubert, Bruce D.; Squiers, Thomas S.; Marchette, Donald; Buckley, Jack (NOAA/National Marine Fisheries Service, 1984)
      Information on the biology and populations of the shortnose sturgeon, Acipenser brevirostrum, is compiled, reviewed, and analyzed in the FAO species synopsis style. New information indicates this species exhibits biological and life-cycle differences over its north-south latitudinal range and that it is more abundant than previously thought. (PDF file contains 51 pages.)
    • Chaetognatha of the Caribbean Sea and adjacent areas

      Michel, Harding B. (NOAA/National Marine Fisheries Service, 1984)
      This illustrated manual is a guide to the distribution and identification of the 6 genera and 28 species of benthicand planktonic Chaetognatha known to occur in the Caribbean Sea, the Gulf of Mexlco, the Florida Straits, and the southwestern North Atlantic Ocean. As background, previous studies of chaetognaths in these areas are reviewed, gross morphology of the different forms is described, and instructions on methods of preserving and handling specimens preparatory to identification are provided. The key to genera and species is preceeded by a discussion of chaetognath taxonomy. A description of each species, consisting of an abbreviated synonymy, a summary of taxonomically important morphological features, and horizontal and vertical distribution follows the key. The occurrence of species in relation to water masses in the Caribbean and adjacent areas is noted. (PDF file contains 39 pages.)
    • Proceedings of the Ninth and Tenth U.S.-Japan Meetings on Aquaculture

      Sindermann, Carl J. (NOAA/National Marine Fisheries Service, 1984)
      The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the UnitedStates-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries.The UJNR was started by a proposal made during the Third Cabinet-Level Meeting of the Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. In addition to aquaculture, current subjects in the program are desalination of seawater, toxic microorganisms, air pollution, energy, forage crops, national park management, mycoplasmosis, wind and seismic effects, protein resources, forestry, and several joint panels and committees in marine resources research, development, and utilization.Accomplishments include: Increased communications and cooperation among technical specialists; exchanges of information, data, and research findings; annual meetings of the panels, a policy coordinative body; administration staff meetings; exchanges of equipment, materials, and samples; several major technical conferences; and beneficial effects on international relations. (PDF file contains 98 pages.)
    • Identification and estimation of size from the beaks of 18 species of cephalopods from the Pacific Ocean

      Wolff, Gary A. (NOAA/National Marine Fisheries Service, 1984)
      A method of identifying the beaks and estimating body weight and mantle length of 18 species of cephalopodsfrom the Pacific Ocean is presented. Twenty specimens were selected from each of the following cephalopod species: Symplectoteuthis oualaniensis, Dosidicus gigas, Ommastrephes bartramii, S. luminosa, Todarodes pacificus, Nototodarus hawaiiensis, Ornithoteuthis volalilis, Hyaloteuthis pelagica, Onychoteuthis banksii, Pterygioteuthis giardi, Abraliopsis affinis, A. felis, Liocranchia reinhardti, Leachia danae, Histioteuthisheteropsis, H. dofleini, Gonalus onyx, and Loligo opalescens. Dimensions measured on the upper and lower beakare converted to ratios and compared individually among the species using an analysis of variance procedure with Tukey's omega and Duncan's multiple range tests. Significant differences (P =0.05) observed among thespecies' beak ratio means and structural characteristics are used to construct artificial keys for the upper andlower beaks of the 18 species. Upper and lower beak dimensions are used as independent variables in a linearregression model with mantle length and body weight (log transformed). (PDF file contains 56 pages.)
    • A temporal and spatial study of invertebrate communities associated with hard-bottom habitats in the South Atlantic Bight

      Wenner, E. L.; Hinde, P.; Knott, D. M; Van Dolah, R. F. (NOAA/National Marine Fisheries Service, 1984)
      Species composition, biomass, density, and diversity of benthic invertebrates from six bard-bottom areas were evaluated. Seasonal collections using a dredge, trawl, and suction and grab samplers yielded 432, 525, and 845 taxa, respectively. Based on collections wltb the different gear types, species composition of invertebrates was found to change bathymetrically. Inner- and mlddle-shelf sites were more similar to each other in terms of invertebrate species composition than they were to outer-shelf sites, regardless of season. Sites on the inner and outer shelf were grouped according to latitude; however, results suggest that depth is apparently a more important determinant of invertebrate species composition than either season or latitude. Sponges generally dominated dredge and trawl collections in terms of biomass. Generally, cnidarians, bryozoans, and spongesdominated at sites In terms of number of taxa collected.The most abundant smaller macrofauna collected in suction and grab samples were polychaetes, amphipods, and mollusks. Densities of the numerically dominant species changed botb seasonally and bathymetrically, with very few of these species restricted to a specific bathymetrlc zone.The high diversity of invertebrates from hard-bottom sites is attributed to the large number of rare species. No consistent seasonal changes in diversity or number of species were noted for individual stations or depth zones. In addition, H and its components showed no definite patterns related to depth or latitude. However, more species were collected at middle-shelf sites than at inner- or outer-shelf sites, which may be related to morestable bottom temperature or greater habitat complexity in that area. (PDF file contains 110 pages.)
    • Ichthyoplankton of the continental shelf near Kodiak Island, Alaska

      Kendall, Jr. , Arthur W.; Dunn, Jean R. (NOAA/National Marine Fisheries Service, 1985)
      Eleven ichthyoplankton surveys were conducted (1 in 1972 and 10 between 1977 and 1979) in the northeastern Pacific Ocean over the continental shelf off Kodiak Island, Alaska. In the 677 neuston and 632 bongo tows, eggs or larvae of more than 80 fish taxa were found. They were present in every season and throughout the survey area, although more taxa and more individuals were found in summer than in other seasons. Among the more abundant species were the gadid Theragra chalcogramma and several hexagrammids and pleuronectids. The hexagrammids and several coUids were abundant in the neustonic layer, where they spent close to a year as larvae and prejuvenlles. Although the seasonal and geographic distribution of most taxa was complex, two patterns emerged: Late summer-fall spawners produce demersal eggs and have neustonic larvae that remain pelagicfor several months (hexagrammids and some cottlds), and spring-summer spawners have pelagic eggs and larvaethat spend several weeks in the plankton but are not closely associated with the surface (Theragra chalcogramma,pleuronectlds). (PDF file contains 95 pages.)
    • Congrid eels of the Eastern Pacific and key to their leptocephali

      Raju, Solomon N. (NOAA/National Marine Fisheries Service, 1985)
      This study indicates that 13 species of congrid larvae belonging to 8 genera occur in the eastern Pacific. Thespecies are: Ariosoma gilberti; Paraconger californiensis; Paraconger sp.; P. dentatus; Chiloconger labiatus;Taenioconger digueti; T. canabus; Gorgasia punctata; G. obtusa; Gnathophis catalinensis; Hildebrandia nitens;Bathycongrus macrurus; and B. varidens. The morphological and anatomical changes undergone during metamorphosis are useful in the identification of the larvae. Larvae are distributed closer to the coastal waters, and are more common from January to May than from June to December. A key to the larvae was developed based on the myotomal counts, adult vertebral counts, pigmentation patterns, and the nature of the teeth and tail tip to distinguish the genera and species. This study shows that Garman's unidentified larvae, Atopichthys acus and A. cingulus, are two different larval stages of Ariosoma gilberti, and points out that Atopichthys dentatus and A. obtusus belong to Paraconger and Gorgasia, respectively. (PDF file contains 25 pages.)