Keys to families of Cladocera and to subfamilies, genera, species and subspecies of Macrothricidae and Moinidae [Translation from: Leningrad, Fauna SSSR, Crustacea 1 (3), 1971]

Identification keys to families of Cladocera and to subfamilies, genera, species and subspecies of Macrothricidae and Moinidae are given. This translation does not include ecological notes or illustrations.

A livelihoods study of farmers and fishers in Trorbek Pork Village Kandal Province

This is the report of a livelihoods study team working together with villagers from Trorbek Pork in Kandal Province, Cambodia. The livelihoods study is based on the current population census (1998) and key informant interviews: 10 to 70 villagers (50% women) representing the 140 families of Trorbek Pork Village, Kampong Kong Commune, Koh Thom District, Kandal Province. (PDF contains 40 pages)

Abundance and Distribution of Ichthyoplankton along an Inshore-Offshore Transect in Onslow Bay, North Carolina

The distribution and abundance of ichthyoplankton was investigated from November 1979 to March 1980 along a transect from coastal to continental slope waters in Onslow Bay, North Carolina. Representatives of 66 families were collected; 24 of which were tropical families, a category that also includes families of typically oceanic and deep-sea fishes. Larvae of tropical species were collected in coastal and shelf waters, demonstrating the intrusion of Gulf Stream waters onto the continental shelf. From December through March, frontal waters that separated cold open-shelf surface waters from warm Gulf Stream surface waters were observed. Higher abundances of fish larvae were sometimes, but not consistently, associated with frontal waters. A great diversity of taxa was collected in offshore waters, and densities of larvae were low in coastal waters; low densities were attributed to gear selectivity rather than low larval abundance. Larvae of commercially and recreationally important estuarine-dependent species, especially Leiostomus xanthus and Micropogonias undulatus, were dominant components of the ichthyoplankton. Representatives of the families Bothidae, Clupeidae, Gadidae, Gonostomatidae, Myctophidae, Ophidiidae, and Sparidae were also important components of the ichthyoplankton. Larvae of species representing two strikingly different life history types-mesopelagic and estuarine-dependent frequently cooccurred.(PDF file contains 32 pages.)

Larvae of Nearshore Fishes in Oceanic Waters near Oahu, Hawaii

Larvae of over 50 families of nearshore fishes were taken in oceanic waters about 13 km offshore of the leeward (southwest) coast of Oahu, Hawaii during 1977-78, The five most frequently taken families (Labridae, Parapercidae, Serranidae, Gobiidae, and Carangidae) made up over 50% of the total nearshore larvae. Most other families were taken very infrequently. Comparison of catch data from three types of nets indicated that 1.25-m diameter bongo nets often sampled larvae as well or better than a 3-m Isaacs-Kidd trawl and that smaller, 70-cm diameter bongo nets were often as effective as the larger nets for certain abundant taxa. Only a few taxa showed evidence of seasonal patterns in abundance. Irregular temporal variability in abundance of some taxa may have been related to occasional recent influxes of surface water from closer to shore. Most larvae taken were late preflexion stage or older. Densities of even the most abundant taxa were rarely greater than 0.001 m-3. The nearshore fish larvae were not dominated by taxa with large larvae or with larvae possessing apparent specializations to pelagic existence, Most taxa taken were pelagic spawners as adults, but larvae of demersal spawners were roughly as well represented as demersal spawners are among the nearshore fish fauna. Previous studies of waters closer to shore probably sampled insufficient volumes for any but a few exceptionally abundant taxa. Sampling with volumes filtered of the order of 104-105 m3 will be necessary to determine if the dominant taxa taken by the present study are ever more abundant closer to shore, (PDF file contains 23 pages.)

Catalog of Osteological Collections of Aquatic Mammals from Mexico

This paper compiles available information on osteological and other anatomical specimens of at least 51 species of aquatic mammals (34 extant, one recently extinct and 16 fossil) collected in Mexico between 1868 and 1990 and housed in 29 scientific institutions (18 in the USA, nine in Mexico, one in the Netherlands, and one in England). These collections contain a total of 1427 specimens representing 10 families of odontocetes (Squalodontidaet , Rhabdosteidaet , Pontoporiidae, Albireonidaet , Monodontidae, Phocoenidae, Delphinidae, Ziphiidae, Kogiidae, and Physeteridae), three of mysticetes (Cetotheridaet , Eschrichtiidae, and Balaenopteridae), three of carnivores (Otariidae, Phocidae, and Mustelidae) and one of sirenians (Trichechidae). Of the aquatic mammals recorded from Mexico, seven species are not represented by specimens (Stenella frontalis, Lagenodelphis hosei, Feresa attenuata, Hyperoodon sp., Eubalaena glacialis, Balaenoptera borealis, and Enhydra lutris). (PDF file contains 40 pages.)

Icthyofauna of Oramiriukwa River in Imo State, Nigeria

Oramiriukwa one of the rivers in the Imo River drainage basin runs approximately a 14.0km course from its headwaters in Abba Isu (Nwangele LGA) and discharge into Otamiri River. Based on the fish catches of local fishermen using a variety of fishing gear in a sampling station in Emekuku (Owerri LGA), a total of 17 families of fish consisting of 27 species were identified in the river. In the January sample the most numerically abundant species were Tilapia zilli (12.5%). Calamoichthys calabaricus (8.7%) and T. guineensis (8.6%). In the July samples the most numerically abundant species were Mastacemblus loenbergii (9.2%). T. zilli (7.2%) and Hemichromis fasciatus (6.6%). The Shannon Weiner Diversity index for Oranmiriukwa River was high (1.305) implying a relatively diversified and equilibrated fish community

The avifauna of Laguna Llancanelo (Mendoza, Argentina), a South American wetland of international importance

Laguna Llancanelo is a large (40,000 ha), very shallow (less than 3 m deep), inland saline waterbody, located in southern Mendoza, Argentina. A survey of the avifauna was undertaken during 1983 to 1985; field trips were made mostly to the northeastern and central-western sectors of the lagoon, in the months of April, May, September, October and December. Complementary studies were made by an aerial survey and assessments of terrestrial birds in the surroundings of the lagoon. A total of 64 species in 22 families of birds usually associated with aquatic environments were recorded. The best-represented families of aquatic birds in terms of numbers of species were: Anatidae (13 swans, geese, ducks), Scolopacidae (7 sandpipers and other small waders), Ardeidae (6 herons, bitterns, egrets, Podicipedidae (4 grebes), Rallidae (4 rails, coots) and Charadriidae (4 plovers, lapwings). The most abundant nesting birds on the lagoon were: Black-necked swan Cygnus melancoryphus (824), silvery grebe Podiceps occipitalis (202) and black-crowned night heron Nycticorax nycticorax (100).

Provisional atlas of the freshwater leeches of the British Isles

Distribution maps were included in the second edition of the F.B.A. Scientific Publication on British freshwater leeches (Mann 1964). When that publication was extensively revised and enlarged to include a review of the literature on the ecology of leeches (Elliott & Mann 1979), it was decided that new maps should be published separately. The original maps were based on 1097 records whereas 4198 records were used for the new maps. The total British Isles list comprises sixteen species, thirteen genera and four families of leeches.

Seasonal variability in ichthyoplankton abundance and assemblage composition in the northern Gulf of Mexico off Alabama

Multiyear ichthyoplankton surveys used to monitor larval fish seasonality, abundance, and assemblage structure can provide early indicators of regional ecosystem changes. Numerous ichthyoplankton surveys have been conducted in the northern Gulf of Mexico, but few have had high levels of temporal resolution and sample replication. In this study, ichthyoplankton samples were collected monthly (October 2004–October 2006) at a single station off the coast of Alabama as part of a long-term biological survey. Four seasonal periods were identified from observed and historic water temperatures, including a relatively long (June–October) “summer” period (water temperature >26°C). Fish egg abundance, total larval abundance, and larval taxonomic diversity were significantly related to water temperature (but not salinity), with peaks in the spring, spring–summer, and summer periods, respectively. Larvae collected during the survey represented 58 different families, of which engraulids, sciaenids, carangids, and clupeids were the most prominent. The most abundant taxa collected were unidentified engraulids (50%), sand seatrout (Cynoscion arenarius, 7.5%), Atlantic bumper (Chloroscombrus chrysurus, 5.4%), Atlantic croaker (Micropogonias undulatus, 4.4%), Gulf menhaden (Brevoortia patronus, 3.8%), and unidentified gobiids (3.6%). Larval concentrations for dominant taxa were highly variable between years, but the timing of seasonal occurrence for these taxa was relatively consistent. Documented increases in sea surface temperature on the Alabama shelf may have various implications for larval fish dynamics, as indicated by the presence of tropical larval forms (e.g., fistularids, labrids, scarids, and acanthurids) in our ichthyoplankton collections and in recent juvenile surveys of Alabama and northern Gulf of Mexico seagrass habitats.

Diet composition and prey selection of the introduced grouper species peacock hind (Cephalopholis argus) in Hawaii

The introduced grouper species peacock hind (Cephalopholis argus), was the dominant large-body piscivore on the Main Hawaiian Island (MHI) reefs assessed by underwater visual surveys in this study. However, published data on C. argus feeding ecology are scarce, and the role of this species in Hawaiian reef ecosystems is presently not well understood. Here we provide the first comprehensive assessment of the diet composition, prey electivity (dietary importance of prey taxa compared to their availability on reefs), and size selectivity (prey sizes in the diet compared to sizes on reefs) of this important predator in the MHI. Diet consisted 97.7% of fishes and was characterized by a wide taxonomic breadth. Surprisingly, feeding was not opportunistic, as indicated by a strongly divergent electivity for different prey fishes. In addition, whereas some families of large-body species were represented in the diet exclusively by recruit-size individuals (e.g., Aulostomidae), several families of smaller-body species were also represented by juveniles or adults (e.g., Chaetodontidae). Both the strength and mechanisms of the effects of C. argus predation are therefore likely to differ among prey families. This study provides the basis for a quantitative estimate of prey consumption by C. argus, which would further increase understanding of impacts of this species on native fishes in Hawaii.

Length-weight relationship of marine fishes from southern Brazil

The relationship between length (L) and weight (W) was estimated for 80 species belonging to 50 families of marine fishes from the shelf and upper slope of southern Brazil (lat. 28°S - 34°S). Sample sizes (n) for different species ranged from 11 to 14 741 specimens collected from commercial landings and research surveys. The fit of the equations (W=aLb) with a and b parameters estimated from regular and functional regression (of log-transformed weight and length data) as well as from a non-linear iterative process using the quasi-Newton algorithm were compared. The non-linear method gave the most accurate estimates in terms of residual sum of squares. Differences were less than 2.3% for n>500 compared with predictive regressions and 1.5% compared with functional regressions. No difference was observed between both predictive and functional regressions. Determination coefficients (r2) increased with sample size, and the highest r2 were obtained for 50of the fishes.

Length-weight relationships of fish from the lagoon of New Caledonia

Length-weight relationships of 335 species of fish of New Caledonia, belonging to 65 families of coral reef fishes, were computed (80%) or assembled from the literature (20% of all cases) to facilitate, among other things, estimation of coral reef fish biomass from visual census.

Growth parameters of marine fishes in Cuban waters

A total of 73 sets of growth parameters for 34 species belonging to 12 families of marine fish caught in Cuban waters are presented. These parameters are compiled from existing studies (58 sets) or derived from data obtained in the original literature (15 sets).

The Bay Scallop, Argopecten irradians, Massachusetts Through North Carolina: Its Biology and the History of Its Habitats and Fisheries

This article covers the biology and the history of the bay scallop habitats and fishery from Massachusetts to North Carolina. The scallop species that ranges from Massachusetts to New York is Argopecten irradians irradians. In New Jersey, this species grades into A. i. concentricus, which then ranges from Maryland though North Carolina. Bay scallops inhabit broad, shallow bays usually containing eelgrass meadows, an important component in their habitat. Eelgrass appears to be a factor in the production of scallop larvae and also the protection of juveniles, especially, from predation. Bay scallops spawn during the warm months and live for 18–30 months. Only two generations of scallops are present at any time. The abundances of each vary widely among bays and years. Scallops were harvested along with other mollusks on a small scale by Native Americans. During most of the 1800’s, people of European descent gathered them at wading depths or from beaches where storms had washed them ashore. Scallop shells were also and continue to be commonly used in ornaments. Some fishing for bay scallops began in the 1850’s and 1860’s, when the A-frame dredge became available and markets were being developed for the large, white, tasty scallop adductor muscles, and by the 1870’s commercial-scale fishing was underway. This has always been a cold-season fishery: scallops achieve full size by late fall, and the eyes or hearts (adductor muscles) remain preserved in the cold weather while enroute by trains and trucks to city markets. The first boats used were sailing catboats and sloops in New England and New York. To a lesser extent, scallops probably were also harvested by using push nets, picking them up with scoop nets, and anchor-roading. In the 1910’s and 1920’s, the sails on catboats were replaced with gasoline engines. By the mid 1940’s, outboard motors became more available and with them the numbers of fishermen increased. The increases consisted of parttimers who took leaves of 2–4 weeks from their regular jobs to earn extra money. In the years when scallops were abundant on local beds, the fishery employed as many as 10–50% of the towns’ workforces for a month or two. As scallops are a higher-priced commodity, the fishery could bring a substantial amount of money into the local economies. Massachusetts was the leading state in scallop landings. In the early 1980’s, its annual landings averaged about 190,000 bu/yr, while New York and North Carolina each landed about 45,000 bu/yr. Landings in the other states in earlier years were much smaller than in these three states. Bay scallop landings from Massachusetts to New York have fallen sharply since 1985, when a picoplankton, termed “brown tide,” bloomed densely and killed most scallops as well as extensive meadows of eelgrass. The landings have remained low, large meadows of eelgrass have declined in size, apparently the species of phytoplankton the scallops use as food has changed in composition and in seasonal abundance, and the abundances of predators have increased. The North Carolina landings have fallen since cownose rays, Rhinoptera bonsais, became abundant and consumed most scallops every year before the fishermen could harvest them. The only areas where the scallop fishery remains consistently viable, though smaller by 60–70%, are Martha’s Vineyard, Nantucket, Mass., and inside the coastal inlets in southwestern Long Island, N.Y.

A survey of the marine nematodes of Chesapeake Bay, Maryland

The study here reported is a survey of the most common non-parasitic nematode families of Chesapeake Bay, Maryland, with descriptions and figures, so that ecological workers and students of invertebrate zoology may be encouraged not to pass over this highly interesting and abundant invertebrate phylum. This survey is not a complete account of the free-living nematode population of the Bay, however, since only the middle section of the Bay was sampled and since the collections were not made systematically throughout the year. The physical and chemical factors of Chesapeake Bay may be found in several publications of the Chesapeake Biological Laboratory, Solomons Island, Maryland, and in the records of the Chesapeake Bay Institute, Annapolis, Maryland.