Sample records for gull island shoal

  1. Effects of herring gulls and great black-backed gulls on breeding piping plovers, South Monomoy Island, Massachusetts. Final Report

    USGS Publications Warehouse

    Keane, S.E.; Fraser, J.D.; Buckley, P.A.

    2002-01-01

    The large population of breeding herring gulls and great black-backed gulls on South Monomoy Island, Cape Cod, Massachusetts has been thought to negatively affect the breeding success of the threatened piping plover. Following the Piping Plover Recovery Plan's call for gull colonies to be removed from piping plover breeding sites, in 1996, the USFWS conducted gull removal on part of South Monomoy Island. We determined relative gull abundance on South Monomoy Island from 1998-2000 by counting gulls within 100-m radius plots located on the shoreline. We quantified piping plover behavior and habitat use by conducting instantaneous and 5-minute behavioral observations. We quantified characteristics of piping plover nesting habitat by measuring characteristics along random transects. We measured gull abundance, beach width, and prey abundance, and then used logistic regression to determine what habitat characteristics influenced piping plover nesting area selection. We monitored piping plover reproductive success and population fluctuations on South Monomoy Island. Gull abundance in the gull-removal area was lower than gull abundance in the reference area throughout the piping plover breeding season. The difference in gull abundance between the areas did not affect piping plover behavior, nest success, chick survival, or productivity. We found that gull removal did not result in an increased piping plover population on the island. In both management areas, prenesting plovers preferred to forage in moist substrate habitats. Wide backshore and open vegetation habitats characterized nesting areas. Broods spent most of their time foraging and preferred moist substrate habitats when available. Plovers were not prevented from occupying more suitable habitat by large gulls. Fewer large gulls were observed near prenesting plovers, plover nests, and plover broods than near random plots. Fewer large gulls were observed in plover nesting areas than in unused areas when the nesting areas were defined by all area within 100-m or 500-m of a plover nest. We argue that this apparent spatial separation between piping plovers and large gulls is due to different habitat preferences among the species. We found that gull removal on South Monomoy Island did not result in increased piping plover reproductive success, and large gulls did not affect breeding piping plovers on South Monomoy Island from 1998-2000.

  2. Population Trends of Gulls and Arctic Terns Nesting in the Belcher Islands, Nunavut

    Microsoft Academic Search

    H. GRANT GILCHRIST; GREGORY J. ROBERTSON

    Little information exists on the population trends of gulls and terns nesting in the Arctic. In 1997, we surveyed the number of glaucous gull (Larus hyperboreus), herring gull (Larus argentatus), and arctic tern (Sterna paradisaea) nests on the Belcher Islands (56?00' - 57?30'N, 79?30' - 80?00'W). We compared our results with the mean number of nests per island counted in

  3. Helminth communities in Audouin's gulls, Larus audouinii from Chafarinas Islands (western Mediterranean).

    PubMed

    Roca, V; Lafuente, M; Carbonell, E

    1999-10-01

    A survey of intestinal helminth communities of Audouin's gulls Larus audouinii, from their breeding colonies in Chafarinas Islands, western Mediterranean, Spain was conducted to determine the abundance and species diversity of intestinal parasites of these birds. The sample of 58 gulls harbored intestinal helminth infracommunities composed of species that are gull generalists, including the digeneans Cardiocephalus longicollis, Knipowitschiatrema nicolai, Condylocotyla pilodora, and Aporchis massiliensis, and the cestode Tetrabothrius cylindraceus. Two nematodes are waterfowl generalists (Cosmocephalus obvelatus and Paracuaria adunca), whereas the digenean Acanthotrema armata is an Audouin's gull specialist. The relative high values of species richness and diversity of the helminth infracommunities are comparable to those of other gulls (Larus philadelphia, Larus canus), probably reflecting the specialized, nonselective fish diet of L. audouinii. PMID:10577744

  4. 33 CFR 334.40 - Atlantic Ocean in vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. 334.40 Section 334.40 Navigation and...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. (a) The danger zone. A circular area with...

  5. 33 CFR 334.40 - Atlantic Ocean in vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. 334.40 Section 334.40 Navigation and...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. (a) The danger zone. A circular area with...

  6. 33 CFR 334.40 - Atlantic Ocean in vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. 334.40 Section 334.40 Navigation and...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. (a) The danger zone. A circular area with...

  7. 33 CFR 334.40 - Atlantic Ocean in vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. 334.40 Section 334.40 Navigation and...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. (a) The danger zone. A circular area with...

  8. 33 CFR 334.40 - Atlantic Ocean in vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. 334.40 Section 334.40 Navigation and...vicinity of Duck Island, Maine, Isles of Shoals; naval aircraft bombing target area. (a) The danger zone. A circular area with...

  9. Character of shell beds flanking Herod Point shoal, southeastern Long Island Sound, New York

    USGS Publications Warehouse

    Poppe, L.J.; Williams, S.J.; Babb, Ivar G.

    2011-01-01

    High biogenic productivity, strong tidal currents, shoal topography, and short transport distances combine to favor shell-bed formation along the lower flanks of a cape-associated shoal off Herod Point on Long Island, New York. This shell bed has a densely packed, clast-supported fabric composed largely of undegraded surf clam (Spisula solidissima) valves. It is widest along the central part of the western flank of the shoal where topographic gradients are steep and a stronger flood tide results in residual flow. The bed is narrower and thinner toward the landward margins where currents are too weak to transport larger valves and topographic gradients are gentle, limiting bed-load transport mechanisms by which the shells are concentrated. Reconnaissance mapping off Roanoke Point suggests that shell beds are also present at the other cape-associated shoals off northeastern Long Island, where relatively similar geomorphic and oceanographic conditions exist. These shell beds are important to the Long Island Sound ecosystem because they provide complex benthic habitats of rough and hard substrates at the boundary between the muddy basin floor and mobile sand of the shoals. ?? 2011, the Coastal Education & Research Foundation (CERF).

  10. Selecting islands and shoals for conservation based on biological and aesthetic criteria

    USGS Publications Warehouse

    Knutson, M.G.; Leopold, D.J.; Smardon, R.C.

    1993-01-01

    Consideration of biological quality has long been an important component of rating areas for conservation. Often these same areas are highly valued by people for aesthetic reasons, creating demands for housing and recreation that may conflict with protection plans for these habitats. Most methods of selecting land for conservation purposes use biological factors alone. For some land areas, analysis of aesthetic qualities is also important in describing the scenic value of undisturbed land. A method for prioritizing small islands and shoals based on both biological and visual quality factors is presented here. The study included 169 undeveloped islands and shoals a??0.8 ha in the Thousand Islands Region of the St. Lawrence River, New York. Criteria such as critical habitat for uncommon plant and animal species were considered together with visual quality and incorporated into a rating system that ranked the islands and shoals according to their priority for conservation management and protection from development. Biological factors were determined based on previous research and a field survey. Visual quality was determined by visual diagnostic criteria developed from public responses to photographs of a sample of islands. Variables such as elevation, soil depth, and type of plant community can be used to classify islands into different categories of visual quality but are unsuccessful in classifying islands into categories of overall biological quality.

  11. Ustica Island (Tyrrhenian Sea, Italy): from shoaling to emergent stage

    Microsoft Academic Search

    L. B. Marinoni; G. Pasquaré; L. Vezzoli

    2003-01-01

    Ustica is a volcanic island located in the southern Tyrrhenian sea, ~60 km NW of Sicily. As usual for volcanic ocean islands, its exposed part (8.6 km2, 248 m max elevation, mostly of Pleistocene age), is a small fraction of the whole edifice which rises from ~2000 m depth. Its 5-pointed-star shape is slightly elongated in a NE direction. A

  12. Marine Algae of French Frigate Shoals, Northwestern Hawaiian Islands: Species List and Biogeographic Comparisons

    Microsoft Academic Search

    Peter S. Vroom; Kimberly N. Page; Kimberly A. Peyton; J. Kanekoa Kukea-Shultz

    2006-01-01

    French Frigate Shoals represents a relatively unpolluted tropical Pa- cific atoll system with algal assemblages minimally impacted by anthropogenic activities. This study qualitatively assessed algal assemblages at 57 sites, thereby increasing the number of algal species known from French Frigate Shoals by over 380% with 132 new records reported, four being species new to the Ha- waiian Archipelago, Bryopsis indica,

  13. Soldado virus from Ornithodoros (Alectorobius) maritimus (Ixodoidea: Argasidae) infesting herring gull nests on Puffin Island, Northern Wales.

    PubMed

    Converse, J D; Hoogstraal, H; Moussa, M I; Evans, D E

    1976-06-01

    Three strains of Soldado (SOL) virus (Hughes serogroup) were isolated from nymphal and adult Ornithodoros (Alectorobius) maritimus Vermeil et Marguet collected in and near nests of the Herring Gull, Larus a. argentatus Pontoppidan, on Puffin Island, northern Wales. Reciprocal complement fixation (CF) titration results demonstrated recovered virus strains to be SOL virus and antigenically distinct from other Hughes serogroup members. All isolates killed mice and guinea pigs, and 1-2 day old domestic chicks when inoculated intracerebrally. PMID:9805

  14. SABINE'S GULL FLOCK RESPONSE

    Microsoft Academic Search

    MICHAEL R. NORTH

    1995-01-01

    Information on the breeding biology of Sabine's Gulls (Xema sabini) is very limited. Parmelee et al. (1967) detailed the species' life history on Victoria Island, northern Canada. Abraham (1986) quantified nesting and brood-rearing chronology and success and noted a strong relationship between nesting Sabine's Gulls and Arctic Terns (Sterna paradisaea), while Abraham and Ankney (1984) described partitioning of food resources

  15. Effect of interannual variations in sea-surface temperature on egg-laying parameters of black-tailed gulls ( Larus crassirostris ) at Teuri Island, Japan

    Microsoft Academic Search

    Naoki Tomita; Yasuaki Niizuma; Masaoki Takagi; Motohiro Ito; Yutaka Watanuki

    2009-01-01

    Sea-surface temperature (SST) directly and indirectly affects the distribution and abundance of prey species for seabirds,\\u000a so we expect variation in SST to be associated with variation in seabird life history traits. In black-tailed gulls (Larus crassirostris) at Teuri Island in northern Hokkaido, Japan, we investigated the diet of the gulls prior to egg laying in 2004 and 2005,\\u000a and

  16. NEGATIVE INTERSPECIES INTERACTIONS IN A GLAUCOUS-WINGED GULL COLONY ON PROTECTION ISLAND, WASHINGTON

    E-print Network

    Cowles, David L.

    avoided by 2010. We suggest that predation by Bald Eagles (Haliaeetus leucocephalus) may also be affecting colony. Key words: Bald Eagle, competition, Dune Grass, Glaucous-winged Gull, Haliaeetus leucocephalus

  17. Shoals Marine Laboratory

    NSDL National Science Digital Library

    Located on 95 acre Appledore Island, Isles of Shoals in the Gulf of Maine, this near-pristine environment allows students to study many aspects of intertidal and sub-tidal ecology. Only open in the warmer months, SML offers a truly unique experience to graduate, undergraduate, and high school students, as well as adults wanting to further their education. Site features information on accessing the island and SML's special programs.

  18. Can rats prey on gull eggs? An experimental approach

    Microsoft Academic Search

    Jordi Prieto; Jacob González-Solís; Xavier Ruiz; Lluís Jover

    2003-01-01

    Black rat Rattus rattus populations can reach high densities on the Mediterranean islands, as has been the case on the Chafarinas Islands (Western Mediterranean coast) in the last decade. This archipelago holds the second largest breeding population of Audouin's gull Larus audouinii and an important population of yellow-legged gull Larus cachinnans. Circumstantial evidences of rat predation upon Audouin's gull eggs

  19. Long term monitoring of pollutants in eggs of Yellow-legged Herring Gull from Capraia island (Tuscan Archipelago).

    PubMed

    Focardi, S; Fossi, C; Lambertini, M; Leonzio, C; Massi, A

    1988-01-01

    Chlorinated hydrocarbons (hexachlorobenzene, lindane, pp'DDE, polychlorinated biphenyls) and trace elements (Hg, Se, Cd, Pb) were determined in eggs of Yellow-legged Herring Gull (Larus cachinnans) collected in an island of the Tyrrhenian Sea during the period 1981-1986. PCBs levels vary on the average between 30.4?g g(-1) d.w. in 1981 to 56.1 ?g g(-1) d.w. in 1983. The capillary chromatograms revealed the presence of about 30 somers of PCBs without significant variations in the eggs of the same year; more than 50% of the residues is made up only three isomers: the 22'44'55', the 22'344'5' and the 22'344'55'. Average DDE residues were 7-8 times lower than those of PCBs and declined during the period (from 9.2 ?g g(-1) d.w. in 1981 to 4.5 ?g g(-1) d.w. in 1986). Cadmium and lead are present in low concentrations. The average levels of mercury and selenium are around 2-2.5 ?g g(-1) d.w., and a cumulative correlation, on a molar basis, exists between these two elements. PMID:24248526

  20. 15. Photo copy of drawing, May, 3, 1963. STRATFORD SHOAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Photo copy of drawing, May, 3, 1963. STRATFORD SHOAL L/S FIRE DETECTION AND FIRE EXTINGUISHING SYSTEMS. Drawing no. 03-2723, U.S. Coast Guard Civil Engineering Unit, Warwick, Rhode Island. - Stratford Shoal Lighthouse, Long Island Sound, Bridgeport, Fairfield County, CT

  1. Aerial estimation of the size of gull breeding colonies

    USGS Publications Warehouse

    Kadlec, J.A.; Drury, W.H.

    1968-01-01

    Counts on photographs and visual estimates of the numbers of territorial gulls are usually reliable indicators of the number of gull nests, but single visual estimates are not adequate to measure the number of nests in individual colonies. To properly interpret gull counts requires that several islands with known numbers of nests be photographed to establish the ratio of gulls to nests applicable for a given local census. Visual estimates are adequate to determine total breeding gull numbers by regions. Neither visual estimates nor photography will reliably detect annual changes of less than about 2.5 percent.

  2. Ship Shoal as a prospective borrow site for barrier island restoration, coastal south-central Louisiana, Usa: Numerical wave modeling and field measurements of hydrodynamics and sediment transport

    USGS Publications Warehouse

    Stone, G.W.; Pepper, D.A.; Xu, J.; Zhang, X.

    2004-01-01

    Ship Shoal, a transgressive sand body located at the 10 m isobath off south-central Louisiana, is deemed a potential sand source for restoration along the rapidly eroding Isles Dernieres barrier chain and possibly other sites in Louisiana. Through numerical wave modeling we evaluate the potential response of mining Ship Shoal on the wave field. During severe and strong storms, waves break seaward of the western flank of Ship Shoal. Therefore, removal of Ship Shoal (approximately 1.1 billion m3) causes a maximum increase of the significant wave height by 90%-100% and 40%-50% over the shoal and directly adjacent to the lee of the complex for two strong storm scenarios. During weak storms and fair weather conditions, waves do not break over Ship Shoal. The degree of increase in significant wave height due to shoal removal is considerably smaller, only 10%-20% on the west part of the shoal. Within the context of increasing nearshore wave energy levels, removal of the shoal is not significant enough to cause increased erosion along the Isles Dernieres. Wave approach direction exerts significant control on the wave climate leeward of Ship Shoal for stronger storms, but not weak storms or fairweather. Instrumentation deployed at the shoal allowed comparison of measured wave heights with numerically derived wave heights using STWAVE. Correlation coefficients are high in virtually all comparisons indicating the capability of the model to simulate wave behavior satisfactorily at the shoal. Directional waves, currents and sediment transport were measured during winter storms associated with frontal passages using three bottom-mounted arrays deployed on the seaward and landward sides of Ship Shoal (November, 1998-January, 1999). Episodic increases in wave height, mean and oscillatory current speed, shear velocity, and sediment transport rates, associated with recurrent cold front passages, were measured. Dissipation mechanisms included both breaking and bottom friction due to variable depths across the shoal crest and variable wave amplitudes during storms and fair-weather. Arctic surge fronts were associated with southerly storm waves, and southwesterly to westerly currents and sediment transport. Migrating cyclonic fronts generated northerly swell that transformed into southerly sea, and currents and sediment transport that were southeasterly overall. Waves were 36% higher and 9% longer on the seaward side of the shoal, whereas mean currents were 10% stronger landward, where they were directed onshore, in contrast to the offshore site, where seaward currents predominated. Sediment transport initiated by cold fronts was generally directed southeasterly to southwesterly at the offshore site, and southerly to westerly at the nearshore site. The data suggest that both cold fronts and the shoal, exert significant influences on regional hydrodynamics and sediment transport.

  3. Argas (Argas) monolakensis, new species (Acari: Ixodoidea: Argasidae), a parasite of California gulls on islands in Mono Lake, California: description, biology, and life cycle.

    PubMed

    Schwan, T G; Corwin, M D; Brown, S J

    1992-01-01

    Argas (Argas) monolakensis, n. sp., is described from adults, nymphs, and larvae collected from under and around nests of California gulls, Larus californicus Lawrence, on islands in Mono Lake, Mono County, Calif., and from specimens reared in the laboratory. This species is closely related to A. cooleyi Kohls & Hoogstraal, a parasite of cliff swallows, Hirundo pyrrhonota Vieillot, but is easily distinguished by hypostome dentition and roof of Haller's organ in all stages and chaetotaxy of the larvae. This tick was successfully reared and maintained in the laboratory by feeding them on domestic chickens. Larvae require 5-8 d to feed, whereas all postlarval stages feed rapidly within 9-62 min. At Mono Lake, ticks are above ground and seek hosts only at night. The number of nymphal stages varies from 2 to 5 depending on the developmental temperature and sex of the tick. Ticks over winter at Mono Lake as second- to fifth-stage nymphs and adults. Ovarian diapause is common with preoviposition periods in extreme cases lasting up to 20 mo. This tick will readily feed on humans and has the potential to transmit Mono Lake virus, which has been isolated from an estimated 2-8% of ticks on various islands. To date, A. monolakensis is known only from islands in Mono Lake, Calif. PMID:1552533

  4. DDT-induced feminization of gull embryos

    SciTech Connect

    Fry, D.M.; Toone, C.K.

    1981-08-21

    Injection of DDT (1, 1, 1-trichloro-2,2-bis(p-chlorophenyl)ethane) into gull eggs at concentrations comparable to those found in contaminated seabird eggs in 1970 induces abnormal development of ovarian tissue and oviducts in male embryos. Developmental feminization of males is associated with inability to breed as adults and may explain the highly skewed sex ratio and reduced number of male gulls breeding on Santa Barbara Island in southern California.

  5. Model of inner shelf shoal development, Beaufort Sea, Alaska

    SciTech Connect

    Lowry, P.; Nummedal, D.; Reimnitz, E.

    1985-01-01

    At least two types of inner shelf shoals exist in the Beaufort Sea, Alaska. One type is located up to 40 km from the shoreline in an average water depth of 20m and oriented obliquely to the coast. A second type of shoals occur adjacent to existing barrier islands where minimum water depth over the shoal crest may be as little as 30-50cm. The development of shallow water shoals is believed to be a result of barrier island submergence. Dinkum Sands is an example of a shallow water shoal. This linear sand body is located between Cross and Narwhal Islands, 25km northeast of Prudhoe Bay. The shoal complex is 8 km long and less than 2 km wide and has a maximum relief of 5m. Historical data reveal submergence of an island over at least a 25 year period. The proposed initial stage of shoal development occurs when longshore sediment transport between barrier islands is disrupted by numerous events of downdrift tidal inlet breaching. Reduction in the amount of available sediment to each island results in significant coastal erosion (stage 2), manifest as a landward migration of the shoreline and a reduction in barrier elevation. The final stage of the model is barrier submergence. At present the greatest accumulation of sediment on Dinkum Sands occur at the distal extremities of the shoal. These are believed to represent the location of recurved spits at either end of the island prior to submergence. Application of the submergence model to explain deepwater shoal development must await the collection of shallow (10m) whole core data.

  6. INTERBREEDING OF THE GLAUCOUS-WINGED GULL AND WESTERN GULL IN THE PACIFIC NORTHWEST

    Microsoft Academic Search

    J. Michael Scott

    1971-01-01

    The fifth edition of the A.O.U. Check-list (1957) states that the Glaucous-winged Gull (Larus glaucescens} breeds from western Alaska south to Copalis Rocks, Washington. In the southern part of its breeding range (Vancouver Island to Copalis Rocks) it is sympatfic with the northernmost populations of the Western Gull (L. occiden- talis} (Pearse, 1946; Jewett et al., 1953). In the summers

  7. Sabine's Gull (Xema sabini), Ross's Gull (Rhodostethia rosea) and Ivory Gull (Pagophila eburnea) Gulls in the Arctic: A Review

    Microsoft Academic Search

    SVEN BLOMQVIST; MAGNUS ELANDER

    The earliest information on Sabine's gull, Ross's gull and Ivory gull was collected by several heroic arctic explorers during the nineteenth century and the beginning of the twentieth. Ross's gull was discovered in northern Canada in 1823 by James C. Ross and Sabine's gull in northwestern Greenland in 1818 by Edward Sabine. S.A. Buturlin was the first to find the

  8. Polychlorinated camphenes (toxaphenes), polybrominated diphenylethers and other halogenated organic pollutants in glaucous gull ( Larus hyperboreus) from Svalbard and Bjørnøya (Bear Island)

    Microsoft Academic Search

    Dorte Herzke; Geir Wing Gabrielsen; Anita Evenset; Ivan C Burkow

    2003-01-01

    The levels of polychlorinated camphenes (toxaphenes) were investigated in liver samples from 18 glaucous gulls (Larus hyperboreus) from Bjørnøya (74°N, 19°E) and four individuals from Longyearbyen (78°N, 15°E). Additionally brominated flame retardants (BFRs), PCBs and chlorinated pesticides were investigated in liver and intestinal contents of 15 of the glaucous gulls from Bjørnøya. Of the analysed BFRs only 2,2?,4,4?-tetra- and 2,2?,4,4?,5-pentabrominated

  9. Trinity shoal: a reworked deltaic barrier on Louisiana continental shelf

    SciTech Connect

    Suter, J.R.; Penland, S.; Moslow, T.F.

    1985-02-01

    Abandonment and reworking of deltaic complexes of the Holocene Mississippi River have produced a series of sandy shoals on the muddy Louisiana continental shelf. Trinity shoal, one of these transgressive deposits, is located 30 km offshore of Atchafalaya Bay and the Point Au Fer-March Island shell reefs. Approximately 1000 km of high-resolution uniboom and 3.5 kHz subbottom-profile seismic data, taken in this area in 1983 and 1984, provide the data base for this study. Trinity shoal, associated with the abandoned Maringouin delta complex, is a lunate shore-parallel feature approximately 36 km long and 5-10 km wide. Relief on the shoal ranges from 2 to 3 m, and minimum water depths over the shoal vary from -5 to -2 m. The shoal sand body is from 5 to 7 m thick and is composed largely of parallel to low-angle clinoform reflectors. Several levels of buried fluvial channels, ranging in age from early Wisconsinian to Holocene, are associated with the shoal deposit. The occurrence of channel features within the shoal sand itself suggests the presence of tidal inlets, indicating a possible barrier-island origin for the shoal. The underlying deltaic sediments reach approximately 15 m in thickness and are made up of low-angle clinoform reflectors dipping to the southwest. Distributary, bay-fill, estuarine, and buried oyster-reef deposits can be recognized, making these similar to modern Atchafalaya delta deposits. Continued progradation of the Atchafalaya delta will probably result in burial of the Trinity shoal and Maringouin delta deposits by fine-grained sediments, giving these shoal deposits a high-preservation potential and creating an excellent stratigraphic trap.

  10. Effects of introducing foxes and raccoons on herring gull colonies

    USGS Publications Warehouse

    Kadlec, J.A.

    1971-01-01

    Red foxes (Vulpes fulva) and raccoons (Procyon lotor) released at colonies of herring gulls (Larus argentatus) on islands off the Massachusetts coast effectively eliminated the production of young gulls. Annual predator introductions for 2-4 years caused major reductions in colony size and occasionally total abandonment of the island as a colony site. Observations of the experimental islands for 2 years after cessation of predator introductions showed slow repopulation of the islands and lower breeding success than on control islands. The size of the regional population was reduced largely because of the movements of gulls off the experimental islands. The introduced predators are, in most cases, difficult to maintain on the islands; this restricts their utility in population management.

  11. Oilfield Development and Glaucous Gull (Larus hyperboreus) Distribution and Abundance in Central Alaskan Beaufort Sea Lagoons, 1970 - 2001

    Microsoft Academic Search

    LYNN E. NOEL; STEPHEN R. JOHNSON; WILLIAM J. GAZEY

    2006-01-01

    We evaluated aerial survey data for glaucous gulls (Larus hyperboreus) in central Alaskan Beaufort Sea lagoons near the Prudhoe Bay oilfields during June to September 1978 - 2001 for trends in numbers of glaucous gulls, associations with human activity, and confounding relationships with environmental variables. Most glaucous gulls were in barrier island and mainland shoreline habitats, and the total number

  12. Effects of gulls on Piping Plover nest site selection at Monomoy National Wildlife Refuge, Massachusetts

    USGS Publications Warehouse

    Keane, S.E.; Fraser, J.D.; Buckley, P.A.

    2001-01-01

    We examined the effects of Herring and Great Black-backed Gulls on Piping Plover nest site selection on South Monomoy Island, MA, from 1998 to 2000. We compared Piping Plover behavior and nest site selection in a gull-free area to a gull area, and compared Piping Plover nesting area characteristics to areas not used by plovers. We found no difference in the frequency of disturbance by gulls to pre-nesting adult plovers between the two areas. We found fewer gulls near pre-nesting adults than near random points, and fewer gulls in Piping Plover nesting areas than in areas not used by plovers. Proximity to prime foraging habitats and available nesting habitat (wide stretches of open vegetation) may be more important to Piping Plover nest site selection than the presence of gulls.

  13. Gulls identified as major source of fecal pollution in coastal waters: a microbial source tracking study.

    PubMed

    Araújo, Susana; Henriques, Isabel S; Leandro, Sérgio Miguel; Alves, Artur; Pereira, Anabela; Correia, António

    2014-02-01

    Gulls were reported as sources of fecal pollution in coastal environments and potential vectors of human infections. Microbial source tracking (MST) methods were rarely tested to identify this pollution origin. This study was conducted to ascertain the source of water fecal contamination in the Berlenga Island, Portugal. A total of 169 Escherichia coli isolates from human sewage, 423 isolates from gull feces and 334 water isolates were analyzed by BOX-PCR. An average correct classification of 79.3% was achieved. When an 85% similarity cutoff was applied 24% of water isolates were present in gull feces against 2.7% detected in sewage. Jackknifing resulted in 29.3% of water isolates classified as gull, and 10.8% classified as human. Results indicate that gulls constitute a major source of water contamination in the Berlenga Island. This study validated a methodology to differentiate human and gull fecal pollution sources in a real case of a contaminated beach. PMID:24140684

  14. Probable epizootic chlamydiosis in wild California (Larus californicus) and ring-billed (Larus delawarensis) gulls in North Dakota.

    PubMed

    Franson, J C; Pearson, J E

    1995-07-01

    During the summer of 1986, more than 400 California gulls (Larus californicus) and ring-billed gulls (Larvus delawarensis), primarily fledglings, died on an island in Lake Sakakawea near New Town, North Dakota (USA). Mortality was attributed largely to chlamydiosis. Necropsy findings in nine carcasses included splenomegaly (n = 9), hepatomegaly (n = 4), and pericarditis (n = 1). Livers from three California gulls and two ring-billed gulls, and spleens from the same five birds plus a third ring-billed gull were positive for Chlamydia psittaci by the direct immunofluorescence test. Chlamydia psittaci was isolated from separate pools of liver and spleen from one California gull and one ring-billed gull. This is believed to be the first record of epizootic chlamydiosis in gulls and the second report of epizootic chlamydial mortality in wild birds in North America. PMID:8592370

  15. Probable epizootic chlamydiosis in wild California (Larus californicus) and ring-billed (Larus delawarensis) gulls in North Dakota

    USGS Publications Warehouse

    Franson, J.C.; Pearson, J.E.

    1995-01-01

    During the summer of 1986, more than 400 California gulls (Larus californicus) and ring-billed gulls (Larvus delawarensis), primarily fledglings, died on an island in Lake Sakakawea near New Town, North Dakota (USA). Mortality was attributed largely to chlamydiosis. Necropsy findings in nine carcasses included splenomegaly (n = 9), hepatomegaly (n = 4), and pericarditis (n = 1). Livers from three California gulls and two ring-billed gulls, and spleens from the same five birds plus a third ring-billed gull were positive for Chlamydia psittaci by the direct immunofluorescence test. Chlamydia psittaci was isolated from separate pools of liver and spleen from one California gull and one ring-billed gull. This is believed to be the first record of epizootic chlamydiosis in gulls and the second report of epizootic chlamydial mortality in wild birds in North America.

  16. Research on Defence Behaviour in a Common Gull (Larus Canus) Colony during Breeding

    Microsoft Academic Search

    Rimantas R. Budrys; Remigijus Gegelevi?ius

    2002-01-01

    The research was carried out on the Didžioji Island, Lake Kretuonas (eastern Lithuania). A stuffed Raven (Corvus corax) was displayed in a Common Gull (Larus canus) colony during different breeding stages and attacks on the stuffed Raven made by Common Gulls flying higher and lower than 1 m above it as well as attacks of a direct contact were recorded.

  17. Polychlorinated camphenes (toxaphenes), polybrominated diphenylethers and other halogenated organic pollutants in glaucous gull (Larus hyperboreus) from Svalbard and Bjørnøya (Bear Island).

    PubMed

    Herzke, Dorte; Gabrielsen, Geir Wing; Evenset, Anita; Burkow, Ivan C

    2003-01-01

    The levels of polychlorinated camphenes (toxaphenes) were investigated in liver samples from 18 glaucous gulls (Larus hyperboreus) from Bjørnøya (74 degrees N, 19 degrees E) and four individuals from Longyearbyen (78 degrees N, 15 degrees E). Additionally brominated flame retardants (BFRs), PCBs and chlorinated pesticides were investigated in liver and intestinal contents of 15 of the glaucous gulls from Bjørnøya. Of the analysed BFRs only 2,2',4,4'-tetra- and 2,2',4,4',5-pentabrominated diphenylethers (PBDE 47 and 99) could be detected. The concentrations ranged between 2 and 25 ng/g ww. In addition, high resolution measurements with GC/HRMS revealed the existence of several, not quantified, PBDEs and polybrominated biphenyls (PBBs) congeners in the samples. B9-1679 and B8-1413 were the dominating toxaphenes with median concentrations of 8 and 15 ng/g ww. Concentrations of toxaphenes and PBDEs were up to 100-times lower than the concentrations of PCB and some of the pesticides. PCB and p,p/-DDE constituted 90% of the contaminants found. PMID:12521115

  18. Male and Female Parental Roles in the Western Gull under Different Environmental Conditions

    E-print Network

    Pierotti, Raymond

    1981-07-01

    I examined variation in parental care in the Western Gull (Larus occidentalis), spending two seasons on Southeast Farallon Island (SEFI), where the population was large and competition for breeding space appeared to be high. During the first season...

  19. Forster's tern chick survival in response to a managed relocation of predatory California gulls

    USGS Publications Warehouse

    Ackerman, Joshua T.; Herzog, Mark P.; Hartman, C. Alex; Herring, Garth

    2014-01-01

    Gull populations can severely limit the productivity of waterbirds. Relocating gull colonies may reduce their effects on nearby breeding waterbirds, but there are few examples of this management strategy. We examined gull predation and survival of Forster's tern (Sterna forsteri) chicks before (2010) and after (2011) the managed relocation of the largest California gull (Larus californicus) colony (24,000 adults) in San Francisco Bay, California. Overall, survival of radio-marked Forster's tern chicks from hatching to fledging was 0.22?±?0.03 (mean?±?SE), and daily survival rates increased with age. Gulls were the predominant predator of tern chicks, potentially causing 54% of chick deaths. Prior to the gull colony relocation, 56% of radio-marked and 20% of banded tern chicks from the nearest tern colony were recovered dead in the gull colony, compared to only 15% of radio-marked and 4% of banded chicks recovered dead from all other tern colonies. The managed relocation of the gull colony substantially increased tern chick survival (by 900%) in the nearby (3.8?km) reference tern colony (0.29?±?0.10 in 2010 and 0.25?±?0.09 in 2011). Among 19 tern nesting islands, fledging success was higher when gull abundance was lower at nearby colonies and when gull colonies were farther from the tern colony. Our results indicate that the managed relocation of gull colonies away from preferred nesting areas of sensitive waterbirds can improve local reproductive success, but this conservation strategy may shift gull predation pressure to other areas or species.

  20. Breeding biology of Sabine’s gull ( Xema sabini ) in the Canadian high Arctic

    Microsoft Academic Search

    Mark L. Mallory; Kelly A. Boadway; Shanti E. Davis; Mark Maftei

    The Sabine’s gull (Xema sabini) is a small seabird that breeds in select locations across the circumpolar Arctic, but there have been few studies on its\\u000a breeding biology, particularly from the high Arctic. We studied nesting phenology, breeding effort, and breeding success of\\u000a Sabine’s gulls over 5 years at a colony on a small island (Nasaruvaalik) in the Canadian high Arctic.

  1. Herring gull eggs as bioindicators for chlorinated hydrocarbons (contribution to the German Federal Environmental Specimen Bank).

    PubMed

    Oxynos, K; Schmitzer, J; Kettrup, A

    1993-11-01

    From its position in the marine food chain, the herring gull (Larus argentatus) is a suitable indicator for the level of contamination of its habitats with lipophilic chemicals, especially the chlorinated hydrocarbons. The gull's utility as an indicator is demonstrated by investigations performed at Trischen island in the Elbe estuary and Alte Mellum island situated in the Weser estuary, when judged by their ability to reflect variations in pollution levels. The use of the analysis technique developed and standardized for the German Environmental Specimen Bank gives comparable results for both temporal and spatial variations for contamination levels on the different islands in the Wadden Sea area (North Sea coast) of Germany. PMID:8272843

  2. Density-independent survival of wild lake trout in the Apostle Islands area of Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Schram, Stephen T.; Selgeby, James H.; Swanson, Bruce L.

    1995-01-01

    The lake trout (Salvelinus namaycush) stock at Gull Island Shoal in western Lake Superior was one of only a few stocks of lean lake trout in the Great Lakes that survived overfishing and predation by the sea lamprey (Petromyzon marinus). Since the mid 1960s, the abundance of wild recruits measured at age 0 and the number of age-7 to -11 wild fish recruited to the fishable stock have increased. We used the Varley-Gradwell method to test for density-dependent survival between these life stages. Survival from age-0 to ages 7-11 was not affected by increasing density, which suggests that further increases in recruitment and stock size are still possible. We suggest that testing for the existence of density-dependent survival can be used to indicate when lake trout populations are rehabilitated.

  3. Feeding Ecology and the Concentration of Organochlorines in Glaucous Gulls

    Microsoft Academic Search

    J. O. Bustnes; K. E. Erikstad; V. Bakken; F. Mehlum; J. U. Skaare

    2000-01-01

    We investigated the blood concentrations of organochlorines (OCs) and the diet of glaucous gulls Larus hyperboreus breeding in two neighbouring areas at Bear Island in the Barents Sea, north-eastern Atlantic. One area was situated on the edge of the large seabird cliff, about 100–150 m above sea level. The second area was about 1–2 km from the seabird cliff, and

  4. Organochlorines in Greenland glaucous gulls ( Larus hyperboreus) and Icelandic gulls ( Larus glaucoides)

    Microsoft Academic Search

    M Cleemann; F Riget; G. B Paulsen; R Dietz

    2000-01-01

    Glaucous gulls (Larus hyperboreus) and Icelandic gulls (Larus glaucoides) were sampled in 1994 from four different areas in Greenland, three on the west coast and one on the east coast. Livers of 93 glaucous gulls and seven Icelandic gulls were analysed for polychlorinated biphenyls (PCBs, IUPAC Nos. 28, 31, 52, 101, 105, 118, 138, 153, 156 and 180), DDTs (p,p?-DDE,

  5. Gulls (Laridae) as frugivores and seed dispersers

    Microsoft Academic Search

    Maria Calvino-Cancela

    2011-01-01

    Many gull species (Laridae) are opportunistic feeders with diverse diets. Seeds and fruits are common in gull diets, often\\u000a in small proportions but sometimes dominant in certain periods and areas. Moreover, the large body sizes and high population\\u000a densities of gulls increase their ecological importance. Hence, they can be significant seed dispersers even with relatively\\u000a few seeds in diets. Gulls

  6. Reductions in Gull Populations Improve Beachwater Quality.

    EPA Science Inventory

    BACKGROUND. Gulls are often cited as an important source of fecal pollution to surface waters, and fecal indicator bacteria (FIB) concentrations have been shown to be significantly correlated with gull populations. However, it is unclear whether gull contamination poses a risk to...

  7. Structure of the New England herring gull population

    USGS Publications Warehouse

    Kadlec, J.A.; Drury, W.H.

    1968-01-01

    Measurements of the rates of population increase, reproduction, and mortality together with an observed age ratio, were used to analyze the population of the Herring Gull in New England. Data from sporadic censuses prior to this study, aerial censuses by the authors, and National Audubon Society Christmas Bird Count indicated that the New England breeding population has been doubling every 12 to 15 years since the early 1900's. This increase has involved founding new colonies and expanding the breeding range There is evidence that 15 to 30% of the adults do not breed in any given year. Sixty-one productivity measurements on 43 islands from 1963 through 1966, involving almost 13,000 nests, showed that from 0.8 to 1.4 young/breeding pair/year is the usual range of rate of production. The age distribution in the population was determined by classifying Herring Gulls by plumage category on an aerial census of the coast from Tampico, Mexico, to Cape Sable, Nova Scotia. Of the 622,000 gulls observed, 68% were adults, 17% were second- and third-year birds, and 15% were first-year birds. Mortality rates derived from band recovery data were too high to be consistent with the observed rate of population growth, productivity, and age structure. Loss of bands increasing to the rate of about 20%/year 5 years after banding eliminates most of the discrepancy. The age structure and rate of population increase indicate a mortality rate of 4 to 9% for gulls 2 years old or older, compared with the 25 to 30% indicated by band recoveries. The population structure we have developed fits everything we have observed about Herring Gull population dynamics, except mortality based on band recoveries.

  8. No. 2 fuel oil decreases embryonic survival of great black-backed gulls

    USGS Publications Warehouse

    Coon, N.C.; Albers, P.H.; Szaro, R.C.

    1979-01-01

    Field study of the effects of No. 2 fuel oil applications to the eggs of great black-backed gulls on an island off the coast of Maine. Fuel oil applied in amounts of either 5 or 20 ul. All eggs opened 8 da later. Measured survival and estimated age of embryo at time of egg oiling.

  9. A Second Breeding Site for Ross's Gull (Rhodostethia rosea) in Nunavut, Canada

    Microsoft Academic Search

    ARNAUD BÉCHET; JEAN-LOUIS MARTIN; PETER MEISTER; CORINNE RABOUAM

    Only 15 cases of breeding of Ross's gull Rhodostethia rosea are known outside of Siberia. While numerous birds are regularly seen in the fall at Point Barrow, Alaska, until now only one breeding locality has been known for Nunavut, Canada. We found a second breeding locality in Nunavut in the northwestern corner of Prince Charles Island (Foxe Basin). We observed

  10. Aspects of chick growth in Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Eyler, T.B.; Stotts, D.B.; Hatfield, J.S.

    1999-01-01

    Because of concerns about apparent population declines and low productivity of Gull-billed Terns (Sterna nilotica) along the coast of Virginia, we investigated whether food limitations may result in retarded growth rates of young. Several colonies of Gull-billed Terns were monitored from May to July each year from 1994 to 1996 on both sandy barrier islands and marsh/shellpile islands in coastal Virginia. Nests were visited one to three times a week to monitor clutch size and hatching success, and enclosures were installed around selected nests to monitor chick growth from hatching to at least two weeks of age. When comparing chick growth, we found significant year, habitat and hatch order effects. Chicks from marsh shellpiles had higher mass and culmen growth rates than did those from barrier islands, and first-hatched (A) chicks had significantly higher culmen growth rates than did second-hatched (B) chicks. Year effects were only found for mass growth rates. Growth rates of Gull- billed Terns in these Virginia colonies seem to be low relative to those of six other North American tern species from other geographic areas. These findings suggest that growth rates of young Gull-billed Terns, as well as other reproductive parameters, need to be examined in detail in other coastal areas such as Texas, where the species is more abundant, to determine whether our growth results are species- or region-specific.

  11. Alternate reproductive strategies in the California gull

    Microsoft Academic Search

    B. H. Pugesek; P. Wood

    1992-01-01

    Summary  We analysed 6 years of reproduction data for 176 California gulls (Larus californicus) surviving from 1980 to 1988. Using a statistical model adapted from Rao's (1958) and Tucker's (1966) generalized growth curve analysis, we reconstructed the reproductive patterns of gulls aged from 0 to 26 years. Individuals were highly consistent in following one of two patterns of reproduction. In a

  12. Organochlorines in Greenland glaucous gulls (Larus hyperboreus) and Icelandic gulls (Larus glaucoides).

    PubMed

    Cleemann, M; Riget, F; Paulsen, G B; Dietz, R

    2000-01-17

    Glaucous gulls (Larus hyperboreus) and Icelandic gulls (Larus glaucoides) were sampled in 1994 from four different areas in Greenland, three on the west coast and one on the east coast. Livers of 93 glaucous gulls and seven Icelandic gulls were analysed for polychlorinated biphenyls (PCBs, IUPAC Nos. 28, 31, 52, 101, 105, 118, 138, 153, 156 and 180), DDTs (p,p'-DDE, p,p'-DDD, p,p'-DDT), hexachlorocyclohexanes (alpha-, beta- and gamma-HCH), hexachlorobenzene (HCB) and trans-nonachlor (TNC). The overall geometric means of the concentrations found in glaucous gull liver were for sigma PCBs 388 (range 20-5557), for sigma DDTs 363 (17-8604), sigma HCHs 7.4 (1-53), HCB 47 (4-594) and trans-nonachlor 19 (3-187) micrograms kg-1 wet wt., respectively. The geometric means of concentrations in Icelandic gull liver were for sigma PCBs 112 (24-435), for sigma DDTs 95 (25-298), sigma HCHs 2.9 (1.4-5.2), HCB 22 (8-58) and trans-nonachlor 5.1 (2.4-8.6) micrograms kg-1 wet wt., respectively. Significantly (P = 0.05) higher concentrations of PCBs, DDTs and HCHs were found in glaucous gulls at Ittoqqortoormiit at the east coast than in gulls from Qeqertarsuaq at the west coast of Greenland. This tendency was also seen for HCB and trans-nonachlor, but the differences were not statistically significant (P = 0.05). A decreasing trend in organochlorine concentrations followed the East Greenland Current, flowing from north to south down the east coast and to the north on the west coast. Gulls taken from the most northerly sampling area of the west coast, however, showed slightly higher concentrations than those from the central west coast. There appeared to be a tendency for higher concentrations to be found in males than females, and in adults compared to young glaucous gulls, but the differences were not statistically significant (P = 0.05). The concentration ranges found in gulls from Greenland were similar to those reported previously for gulls from northern Norway and Russia. A principal component analysis revealed no obvious link between the presence of higher chlorinated PCBs and higher PCB concentrations in glaucous gulls. Significantly higher proportions of higher chlorinated PCBs were found in glaucous gulls than in Icelandic gulls, and in adult glaucous gulls compared to young gulls of 1-2 calendar years. As no such difference was found between female and male gulls it seems that PCBs of all degrees of chlorination may be passed equally well from mother to offspring. PMID:10682360

  13. Cytochrome P4501A induction and DNA adduct formation in glaucous gulls ( Larus hyperboreus), fed with environmentally contaminated gull eggs

    Microsoft Academic Search

    Lene Østby; Geir Wing Gabrielsen; Åse Krøkje

    2005-01-01

    This study indicates that complex mixtures of pollutants found in the Arctic marine environment have genotoxic effects in glaucous gulls (Larus hyperboreus). DNA adducts were quantified, by the 32P-postlabeling technique, in liver samples from gulls fed with hen eggs (controls) and from gulls fed with environmentally contaminated gull eggs (exposed). All birds were grown and fed under laboratory conditions. Hepatic

  14. ASSORTATIVE MATING WITHOUT COMPLETE REPRODUCTIVE ISOLATION IN A ZONE OF RECENT SECONDARY CONTACT BETWEEN HERRING GULLS

    E-print Network

    BETWEEN HERRING GULLS (LARUS ARGENTATUS) AND CASPIAN GULLS (L. CACHINNANS) Résumé.--La zone de contact.--The zone of secondary contact between Herring Gulls (Larus argentatus) and Caspian Gulls (L. cachinnans

  15. Anticipating the Serving from Charcoal Gull 

    E-print Network

    Unknown

    2011-08-17

    ~s City Ship Channels. Values in water were less than 1 ug/L while values in sediment were less than 100 ng/g. PCB contami"ation cf Atlantic croaker, blue crab, and laughing gull was similar in magnitude to ~t conation. Laughing gulls contained slightly... Uptake Experiments and Analyses of Gulls RESULTS 40 42 49 52 Physical Parameters of Galveston Bay PCBs in Galveston Bay Microbiological Uptake Via Seawater Uptake Via Food DISCUSSION 64 68 75 77 95 105 SUMMARY AND CONCLUSIONS REFERENCES...

  16. Effects of organochlorine contaminants on thyroid hormone levels in Arctic breeding glaucous gulls, Larus hyperboreus.

    PubMed Central

    Verreault, Jonathan; Skaare, Janneche Utne; Jenssen, Bjørn Munro; Gabrielsen, Geir Wing

    2004-01-01

    Studies on glaucous gulls (Larus hyperboreus) breeding in the Barents Sea have reported that high blood levels of halogenated organic contaminants in this species might cause reproductive, behavioral, and developmental stress. However, potential endocrine system modulation caused by contaminant exposure has yet not been reported in this Arctic apical predator. In this present study we aimed to investigate whether the current levels of a selection of organochlorines (OCs) were associated with altered circulating levels of thyroid hormones (THs) in free-ranging adult glaucous gulls breeding at Bear Island in the Barents Sea. Blood concentrations of 14 polychlorinated biphenyls, hexachlorobenzene (HCB), oxychlordane, and p,p' -dichlorodiphenyldichloroethylene (p,p' -DDE) were quantified, in addition to free and total thyroxine (T4) and triiodothyronine (T3), in plasma of 66 glaucous gulls in the spring of 2001. Negative correlations were found between plasma levels of T4 and T4:T3 ratio, and blood levels of OCs in male glaucous gulls. Despite their relatively low contribution to the total OC fraction, HCB and oxychlordane were the most prominent compounds in terms of their negative effect on the variation of the T4:T3 ratio. Moreover, lower T4 levels and T4:T3 ratios were measured in glaucous gulls breeding in a colony exposed to high levels of OCs, compared with a less exposed colony. Levels of T3 were elevated in the high-OC-exposed colony. This may indicate that the glaucous gull is susceptible to changes to TH homeostasis mediated by exposure to halogenated organic contaminants. PMID:15064156

  17. Effects of organochlorine contaminants on thyroid hormone levels in Arctic breeding glaucous gulls, Larus hyperboreus.

    PubMed

    Verreault, Jonathan; Skaare, Janneche Utne; Jenssen, Bjørn Munro; Gabrielsen, Geir Wing

    2004-04-01

    Studies on glaucous gulls (Larus hyperboreus) breeding in the Barents Sea have reported that high blood levels of halogenated organic contaminants in this species might cause reproductive, behavioral, and developmental stress. However, potential endocrine system modulation caused by contaminant exposure has yet not been reported in this Arctic apical predator. In this present study we aimed to investigate whether the current levels of a selection of organochlorines (OCs) were associated with altered circulating levels of thyroid hormones (THs) in free-ranging adult glaucous gulls breeding at Bear Island in the Barents Sea. Blood concentrations of 14 polychlorinated biphenyls, hexachlorobenzene (HCB), oxychlordane, and p,p' -dichlorodiphenyldichloroethylene (p,p' -DDE) were quantified, in addition to free and total thyroxine (T4) and triiodothyronine (T3), in plasma of 66 glaucous gulls in the spring of 2001. Negative correlations were found between plasma levels of T4 and T4:T3 ratio, and blood levels of OCs in male glaucous gulls. Despite their relatively low contribution to the total OC fraction, HCB and oxychlordane were the most prominent compounds in terms of their negative effect on the variation of the T4:T3 ratio. Moreover, lower T4 levels and T4:T3 ratios were measured in glaucous gulls breeding in a colony exposed to high levels of OCs, compared with a less exposed colony. Levels of T3 were elevated in the high-OC-exposed colony. This may indicate that the glaucous gull is susceptible to changes to TH homeostasis mediated by exposure to halogenated organic contaminants. PMID:15064156

  18. Heavy metal and selenium concentrations in eggs of herring gulls (Larus argentatus) : Temporal differences from 1989 to 1994

    Microsoft Academic Search

    J. Burger; M. Gochfeld

    1995-01-01

    Concentrations of five metals and selenium in the eggs of herring gulls (Larus argentatus) were examined at a breeding colony on western Long Island, New York from 1989 to 1994. There were significant yearly differences in lead, cadmium, mercury, selenium, chromium, and manganese. Chromium and cadmium were significantly higher in 1993 compared to the other years. Lead levels were highest

  19. Measurements of shoaling internal waves and turbulence in an estuary

    E-print Network

    Measurements of shoaling internal waves and turbulence in an estuary Clark Richards,1 Daniel 2012; accepted 30 October 2012. [1] The shoaling of horizontally propagating internal waves may energetics, and two main features were studied. First, during a period of shoaling internal waves, turbulence

  20. 18. Photocopy, "Light house for ship shoals, details of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Photocopy, "Light house for ship shoals, details of the apparatus for inserting the piles into the shoal, sheet no. 53", National Archives (8" x 10" print from 4" x 5" negative) - Ship Shoal Light Station, Gulf of Mexico, Theriot, Terrebonne Parish, LA

  1. Data Decision Analysis: Project Shoal

    SciTech Connect

    Forsgren, Frank; Pohll, Greg; Tracy, John

    1999-01-01

    The purpose of this study was to determine the most appropriate field activities in terms of reducing the uncertainty in the groundwater flow and transport model at the Project Shoal area. The data decision analysis relied on well-known tools of statistics and uncertainty analysis. This procedure identified nine parameters that were deemed uncertain. These included effective porosity, hydraulic head, surface recharge, hydraulic conductivity, fracture correlation scale, fracture orientation, dip angle, dissolution rate of radionuclides from the puddle glass, and the retardation coefficient, which describes the sorption characteristics. The parameter uncertainty was described by assigning prior distributions for each of these parameters. Next, the various field activities were identified that would provide additional information on these parameters. Each of the field activities was evaluated by an expert panel to estimate posterior distribution of the parameters assuming a field activity was performed. The posterior distributions describe the ability of the field activity to estimate the true value of the nine parameters. Monte Carlo techniques were used to determine the current uncertainty, the reduction of uncertainty if a single parameter was known with certainty, and the reduction of uncertainty expected from each field activity on the model predictions. The mean breakthrough time to the downgradient land withdrawal boundary and the peak concentration at the control boundary were used to evaluate the uncertainty reduction. The radionuclide 137Cs was used as the reference solute, as its migration is dependent on all of the parameters. The results indicate that the current uncertainty of the model yields a 95 percent confidence interval between 42 and 1,412 years for the mean breakthrough time and an 18 order-of-magnitude range in peak concentration. The uncertainty in effective porosity and recharge dominates the uncertainty in the model predictions, while the other parameters are less important. A two-stage process was used to evaluate the optimal field activities. For all of the field activities combined there were five activities that were found to be "optimal" in terms of uncertainty reduction per unit cost: two-well, natural-gradient, energy budget, and single-well tracer tests, and the vadose zone modeling. A subset of the field activities was chosen such that there would be no duplication in parameter characterization. Of this subset, the vadose zone model, barometric test, energy budget, and the two-well tracer test were found to be optimal for the peak breakthrough time metric, while the single-well tracer test and the hydraulic head measurements are also considered optimal for the peak concentration metric. The environmental tracer activity was not found to be optimal, yet this activity may provide additional information on the transport system. Care must be taken in using this analysis to design a field characterization plan, as many assumptions were required in the analysis. First, many subjective assumptions were required to assess the reliability of the field activities in terms of their ability to reduce the uncertainty in the mean parameters. Actual field characterization may not result in the same reduction in model output uncertainty as estimated by this analysis. Second, this analysis focused on the reduction in model uncertainty due to the reduction in the uncertainty in the mean parameters. If the uncertainty in the mean parameters is reduced to zero, there still exists uncertainty in the natural heterogeneity that can never be reduced to zero. Therefore, this analysis should be used in combination with expert judgement when designing a field characterization strategy.

  2. THE DYNAMICS OF SEASONAL DISTRIBUTION OF GREAT LAKES HERRING GULLS

    E-print Network

    Moore, Frank R.

    THE DYNAMICS OF SEASONAL DISTRIBUTION OF GREAT LAKES HERRING GULLS BY FRANK R. MOORE INTRODUCTION The Herring Gull (Larus arge·tatus)is an abundantspeciesover much of North America, particularly on coastal (1921), and the postbreeding "migration" of Herring Gulls from the Great Lakes has since received much

  3. Novel methoxylated polybrominated diphenoxybenzene congeners and possible sources in herring gull eggs from the Laurentian Great Lakes of North America.

    PubMed

    Chen, Da; Letcher, Robert J; Gauthier, Lewis T; Chu, Shaogang; McCrindle, Robert; Potter, Dave

    2011-11-15

    An increasing number of brominated flame retardants and other brominated substances are being reported in herring gull eggs from the Laurentian Great Lakes basin. Yet, in extracts from gulls' eggs, numerous bromide anion response peaks in electron capture negative ion (ECNI) mass chromatograms remain unidentified. Using archived herring gull egg homogenates, we characterize the structures of three major and three minor, new and unique brominated substances. After extensive cleanup and separation to isolate these substances from the extracts, high-quality ECNI and electron impact (EI) mass spectra revealed fragmentation patterns consistent with congeners of methoxylated polybrominated diphenoxybenzene (MeO-PBDPB), where four congeners contained five bromines and the other two contain four and six bromines, respectively. Optimized, semiquantitative analysis revealed sum concentrations of the MeO-PBDBP congeners ranged from <0.2 to 36.8 ng/g ww in pooled egg homogenates (collected in 2009) from fourteen herring gull colony sites across the Great Lakes, with the highest concentration being for Channel-Shelter Island in Saginaw Bay (Lake Huron). To our knowledge, there are no published reports on the environmental presence and sources of MeO-PBDPBs. We hypothesize that these MeO-PBDPBs are degradation products of the polybrominated diphenoxybenzenes, for example, tetradecabromodiphenoxybenzene (currently marketed as SAYTEX 120) or polybromo 3P2E. MeO-PBDPBs in Great Lakes herring gull eggs indicates their bioaccumulation potential, and raises concerns about their origin, environmental behavior and influences on wildlife and environmental health. PMID:21966880

  4. Living with gulls: the consequences for sandwich terns of breeding in association with black-headed gulls

    Microsoft Academic Search

    E. W. M. Stienen; A. Brenninkmeijer; C. E. Geschiere

    2001-01-01

    We studied the feeding ecology of Sandwich Terns (Sterna sandvicensis) in the presence of kleptoparasitising Blackheaded Gulls (Larus, ridbundus) on the isle of Griend, The Netherlands, between 1992 and 1998. About 30 of all of the food the patents transported to the colony was lost, mainly through intervention by Blackheaded Gulls. Tile gulls mainly took the larger fish, but showed

  5. Hybridization of glaucous gull (Larus hyperboreus) and herring gull (Larus argentatus) in Iceland: mitochondrial and microsatellite data

    Microsoft Academic Search

    Freydis Vigfusdottir; Snæbjorn Palsson; Agnar Ingolfsson

    2009-01-01

    Large white-headed gulls provide an interesting group of birds for studies of hybridization. The group is composed of 20 species of recent origin, often with weak reproductive barriers. Here we report the results from a study on the glaucous gull Larus hyperboreus, an Arctic species which has been breeding in Iceland for centuries, and the herring gull Larus argentatus which

  6. Chromosome Aberrations and DNA Strand Breaks in Glaucous Gull (Larus Hyperboreus) Chicks Fed Environmentally Contaminated Gull Eggs

    Microsoft Academic Search

    Åse Krøkje; Chris Bingham; Ruth Husmo Tuven; Geir Wing Gabrielsen

    2006-01-01

    In this present laboratory study, our results suggest that a complex mixture of pollutants found in the marine environment exerts genotoxic effects on glaucous gull (Larus hyperboreus) chicks fed environmentally contaminated gull eggs. Chromosome aberrations, quantified by cytogenetic analysis of blood cells, and DNA strand breaks, quantified by agarose gel electrophoresis and image data analysis, were determined in glaucous gull

  7. Mercury and other metals in eggs and feathers of glaucous-winged gulls (Larus glaucescens) in the Aleutians

    PubMed Central

    Gochfeld, Michael; Jeitner, Christian; Burke, Sean; Volz, Conrad D.; Snigaroff, Ronald; Snigaroff, Daniel; Shukla, Tara; Shukla, Sheila

    2014-01-01

    Levels of mercury and other contaminants should be lower in birds nesting on isolated oceanic islands and at high latitudes without any local or regional sources of contamination, compared to more urban and industrialized temperate regions. We examined concentrations of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in the eggs, and the feathers of fledgling and adult glaucous-winged gulls (Larus glaucescens) nesting in breeding colonies on Adak, Amchitka, and Kiska Islands in the Aleutian Chain of Alaska in the Bering Sea/North Pacific. We tested the following null hypotheses: 1) There were no differences in metal levels among eggs and feathers of adult and fledgling glaucous-winged gulls, 2) There were no differences in metal levels among gulls nesting near the three underground nuclear test sites (Long Shot 1965, Milrow 1969, Cannikin 1971) on Amchitka, 3) There were no differences in metal levels among the three islands, and 4) There were no gender-related differences in metal levels. All four null hypotheses were rejected at the 0.05 level, although there were few differences among the three test sites on Amchitka. Eggs had the lowest levels of cadmium, lead, and mercury, and the feathers of adults had the lowest levels of selenium. Comparing only adults and fledglings, adults had higher levels of cadmium, chromium, lead and mercury, and fledglings had higher levels of arsenic, manganese and selenium. There were few consistent interisland differences, although levels were generally lower for eggs and feathers from gulls on Amchitka compared to the other islands. Arsenic was higher in both adult feathers and eggs from Amchitka compared to Adak, and chromium and lead were higher in adult feathers and eggs from Adak compared to Amchitka. Mercury and arsenic, and chromium and manganese levels were significantly correlated in the feathers of both adult and fledgling gulls. The feathers of males had significantly higher levels of chromium and manganese than did females. The levels of most metals in feathers are below those known to be associated with adverse effects in the gulls or their predators. However, levels of mercury in some gull eggs are within a range suggesting that several eggs should not be eaten in one day by sensitive humans. PMID:18626778

  8. Birds of Bylot Island and Adjacent Baffin Island, Northwest Territories, Canada, 1979 to 1997

    Microsoft Academic Search

    DENIS LEPAGE; DAVID N. NETTLESHIP; AUSTIN REED

    1998-01-01

    Observations of birds in the Bylot Island region from 1979 to 1997, with emphasis on the southwest part of the island each summer since 1989, revealed an avifauna composed of 63 species, of which 35 were breeding. Thirteen species are new records for the region, including one for the Northwest Territories (black-headed gull Larus ridibundus) and two for the Canadian

  9. Ross's Gulls in the Central Arctic Ocean

    Microsoft Academic Search

    CHRISTIAN HJORT; GUDMUNDUR A. GUDMUNDSSON; MAGNUS ELANDER

    The central Arctic Ocean is difficult to access. As a result, the bird fauna of the area, with its potential input from all around the circumpolar perimeter, is still only little known. The present paper contributes observations on the distribution of Ross's gull (Rhodostethia rosea) made during the Arctic Ocean 96 expedition from mid-July to mid-September 1996, from the Swedish

  10. SEXUAL DIMORPHISM OF LARGE GULLS (LARUS SPP.)

    Microsoft Academic Search

    AGNAR INGOLFSSON

    sponsible for maintaining and increasing the dimorphism, although other basic adaptive functions may also be involved. Smith (1966) found for two species of gulls (Larus glaucoides and L. thayeri) that the difference between the sexes was greatest when the species were allopatric with closely similar species. He suggests (p. 85): \\

  11. THE DISTRIBUTION OF CERTAIN LARGE GULLS

    Microsoft Academic Search

    Pierre Devillets; Guy McCaskie; Joseph R. Jehl

    In the course of investigating the relationships and plumage charac- ters of the large gulls of western North America (Devillets, in prep.) a number of specimens had to be examined, and distributional data checked. Also, field studies, particularly in the San Diego region, northern Baja California, and the Salton Sea, have resulted in a better understanding of the distribution of

  12. Distribution and textural character of surficial sediments, Isles Dernieres to Ship Shoal region, Louisiana

    SciTech Connect

    Williams, S.J.; Circe, R. (Geological Survey, Reston, VA (USA)); Penland, S. (Geological Survey, Baton Rouge, LA (USA))

    1989-09-01

    Since 1986, the US Geological Survey and the Louisiana Geological Survey have undertaken field studies of the physical processes responsible for the widespread and extremely rapid coastal erosion of Louisiana's barriers along the Mississippi River delta plain coast. The study area encompasses the coastal and inner shelf region from Raccoon Point to Sandy Point and includes a database of 12-m long vibracores, surface grab samples, sidescan sonar, high resolution seismic reflection profiles, and precision hydrographic profiles. This paper presents results in the coastal-shelf sector that includes the Isles Dernieres barrier island chain seaward almost 30 km to Ship Shoal. The surface and near-surface sediments of the region reflect fluvial and nearshore marine origin with pervasive evidence of winnowing and reworking by marine processes associated with frequent tropical storms and the passage of winter cold fronts. Beach sediments are remarkably uniform in grain size (fine quartz sand), except for the often abundant presence of carbonate shell debris, and are generally well to very well sorted. The shoreface and inner shelf are mantled with muddy sands and sandy muds, whereas, Ship Shoal is almost wholly fine quartz sand, similar in many sedimentologic respects to the Isles Dernieres. The results are consistent with the model of coastal evolution, presented in 1988, in which Ship Shoal is the prototypical example of a drowned coastal barrier undergoing submarine reworking and landward migration in pace with the rapid rates of sea level rise and subsidence.

  13. Fully Nonlinear Properties of Periodic Waves Shoaling over Slopes1

    E-print Network

    Grilli, Stéphan T.

    . INTRODUCTION In the coastal region, incident ocean waves propagating towards the shore (in direc- tion x; FigFully Nonlinear Properties of Periodic Waves Shoaling over Slopes1 St´ephan T. Grilli 2 , M. ASCE, and Juan Horrillo3 ABSTRACT : Shoaling of finite amplitude periodic waves over a sloping bottom

  14. Measurements of shoaling internal waves and turbulence in an estuary

    E-print Network

    Kelley, Dan

    Measurements of shoaling internal waves and turbulence in an estuary Clark Richards,1 Daniel internal waves may represent an important source of mixing and transport in estuaries and coastal seas of the turbulent energetics, and two main features were studied. First, during a period of shoaling internal waves

  15. Extinction risk to herring gull populations from DDT exposure.

    PubMed

    Nakamaru, Mayuko; Iwasa, Yoh; Nakanishi, Junko

    2002-01-01

    The impact of toxic chemicals on wild animals and plants can be quantified in terms of the enhanced risk of population extinction. To illustrate the method, we estimated it for herring gull (Larus argentatus) populations in Long Island (NY, USA) exposed to DDT (p,p'-dichlorodiphenyltrichloroethane) and its metabolites (abbreviated as DDTs) with a strong biomagnification effect. The method is based on a formula of the mean time to population extinction derived for a stochastic differential equation (the canonical model). The intrinsic rate of natural population growth was estimated from the doubling time of an exponentially growing population and the intensity of the environmental fluctuation from the magnitude of population size fluctuation. The effect of exposure to DDTs in reducing the population growth rate was evaluated based on an age-structured population model by assuming that age-specific fertilities (including chick survivorship) are density dependent and sensitive to DDTs exposure but age-specific survivorships are not. The results are expressed in terms of the risk equivalent-the decrease in the carrying capacity K that causes the same enhancement of extinction risk as chemical exposure at a given level. The high concentration reported in Long Island in the 1960s corresponds to the equivalent loss of carrying capacity by 42.5% when K is 100 (the number of breeding females), and coefficient of variation (CV) = 0.2 (sigma2 = 0.0298) [corrected]. Risk equivalent allows us to compare different risk factors and is useful in mitigation banking. PMID:11804054

  16. Adoption of chicks and the level of relatedness in common gull, Larus canus, colonies: DNA fingerprinting analyses

    Microsoft Academic Search

    Dariusz Bukaci?ski; Monika Bukaci?ska; Thomas Lubjuhn

    2000-01-01

    In common gull colonies on islands of the Vistula River, Poland, adoption of chicks is common. In 1997, we observed 81 chicks from 35 nests. Of these, 19 (23.4%) left their natal broods and were adopted by other pairs. Another 11 (31.4%) were driven from the foreign territory by the owners. Foreign chicks were adopted by 15 pairs (42.9%). Eleven

  17. Mapping islands, reefs and shoals in the oceans surrounding Australia

    NASA Technical Reports Server (NTRS)

    Turner, L. G. (principal investigator)

    1976-01-01

    The author has identified the following significant results. Contours of residual errors were depicted in east and north directions. Contours were constructed from residuals which were determined at 22 ground control points. Residuals at two control points were rejected from contour determination, as their magnitudes were not in keeping with surrounding values. Results obtained so far from depth measurement tests are only tentative. Both sucessful and unsuccessful correlations were depicted between the imagery intensities and bathymetric data. Using the results from nine profile comparisons abstracted from a scene over Torres Strait, where water was generally very clear, an empirical relationship between image intensity (1) and water depth (d) was derived: 1 = 30 - 0.75 d.

  18. Trace element contamination in nestling black-tailed gulls (Larus crassirostris) in Korea.

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2015-05-01

    At Hongdo Island, Gyeongsangnam-do, Korea, a breeding site of black-tailed gull (Larus crassirostris), we collected nestlings from two locations: a "reference" site (n = 10) with no known source of lead contamination and "lighthouse" site (n = 10) with suspected lead contamination from leaded paint. Iron concentrations in the kidney and bone, manganese in the muscle, copper in the bone, lead in the muscle and bone, and cadmium in the liver, muscle, and bone at the reference site were significantly higher than at the lighthouse. Manganese concentrations in the liver and kidney, and lead in the kidney were significantly greater at the lighthouse than at the reference site. Iron, zinc, manganese, copper, lead and cadmium concentrations had tissue-specific accumulation at both sites. Lead concentrations in 10 % of livers and in 80 % of kidneys at the lighthouse, and in 20 % of livers from the reference were within a range considered toxic (>6.00 ?g/g dw in the liver and kidney). Lead concentrations in 50 % of black-tailed gull nestlings at the reference and 80 % nestlings at the lighthouse were greater in livers than in bones, which is suggestive of acute lead exposure. For cadmium, all liver and kidney concentrations from two sites were at a level considered background in birds. Cadmium concentrations of every sample were higher in kidneys than in livers, suggestive of chronic cadmium exposure. Lead concentrations in gull nestlings in the present study were relatively higher than other gull species worldwide, but cadmium concentrations were relatively lower. PMID:25763522

  19. Distribution of polychlorinated biphenyls in marine species from French Frigate Shoals, North Pacific Ocean.

    PubMed

    Miao, X S; Swenson, C; Woodward, L A; Li, Q X

    2000-07-20

    Polychlorinated biphenyls (PCBs) were analyzed in: sediment; coral (Porites evermanni); fish (Stegastes fasciolatus, Neoniphon sammara, Acanthurus triostegus and Mulloidichthys vanicolensis); crab (Grapsus tenuicrustatus); lobster (Panulirus marginatus); and eel (Conger cinereus, Gymnothoraxflavimarginatus, G. undulatus and G. meleagris) samples collected from Tern Island and the corresponding reference samples from Disappearing Island. The two islands are part of French Frigate Shoals, a national wildlife refuge in the North Pacific Ocean. The dominant congeners 118, 138 and 153 represent 22-25, 32-34, 12-39, 37-46 and 30-55% of the sum of PCBs in the coral, sediment, fish, crab and eel, respectively. In general, high trophic species such as eels were found to highly bioaccumulate PCBs. The total average PCB concentrations were as high as 96 and 29 microg/g dry wt. in eels and damselfish, respectively, from Tern Island. The localized behavior and high bioaccumulation potential for PCBs suggest that damselfish are an excellent species for monitoring PCBs in small areas in the ocean. The high average concentrations of the sum of PCBs in different food chain levels suggest that pollution source(s) are around Tern Island and possibly around Disappearing Island. Aroclor 1254 and its analogs are suspected sources responsible for PCBs in the samples. PMID:10943899

  20. Molecular phylogeny and plumage evolution in gulls (Larini)

    Microsoft Academic Search

    P.-A. CROCHET; F. BONHOMME; J.-D. LEBRETON

    2000-01-01

    We used DNA sequence data of the mitochondrial control region and cytochrome b gene to assess phylogenetic relationships among 32 gull species and two outgroup representatives. We tentatively estimated divergence times from transversional substitutions calibrated against DNA-DNA hybridization data. Several strongly supported species groups are identified, but the relationships between these species groups and the rooting of the gull tree

  1. MOLT CYCLES AND SEQUENCES IN THE WESTERN GULL

    Microsoft Academic Search

    STEVE N. G. HOWELL; CHRIS CORBEN

    2000-01-01

    We describe the molt cycle of the Western Gull (Larus occidentalis) in central California on the basis of field observations of unmarked birds. The Western Gull has one partial and one complete molt per year. The first and second partial molts span up to 7 or 8 months, subsequent prealternate molts about 4 to 6 months. The complete prebasic molt

  2. Ross's Gull (Rhodostethia rosea) Breeding in Penny Strait, Nunavut, Canada

    Microsoft Academic Search

    MARK L. MALLORY; H. GRANT GILCHRIST; CAROLYN L. MALLORY

    We found a small, previously undiscovered breeding colony of Ross's gulls (Rhodostethia rosea) in Nunavut, Canada, approximately 80 km from a previous colony location occupied during the 1970s. The birds nested in association with arctic terns (Sterna paradisaea). The collective observations from this region of the High Arctic suggest that Ross's gulls may move colonies each year, or that colony

  3. 850 SHORT COMMUNICATIONS formed by the Yellow-legged Gull which commonly

    E-print Network

    Holberton, Rebecca L.

    850 SHORT COMMUNICATIONS formed by the Yellow-legged Gull which commonly prey on nests of Audouin's Gull, especiallyin sub- colonieswith low densities(Oro and Martinez 1994, Gonzalez-Solis et al. 1995, kleptoparasitismand disturbanceby Yellow-legged Gull on Audouin's Gull in two western Mediterranean colonies,p. 20

  4. Consumption of Migrating Juvenile Salmonids by Gulls Foraging below a Columbia River Dam

    Microsoft Academic Search

    Gregory T. Ruggerone

    1986-01-01

    Consumption of migrating juvenile Pacific salmon Oncorhynchus spp. and steelhead Salmo gairdneri by gulls was estimated below the turbine area of Wanapum Dam on the Columbia River in 1982. Foraging success of the gulls, chiefly ring-billed gulls Larus delawarensis, averaged 65% during bright light conditions and 51% during the evening. The number of salmonids consumed by gulls ranged from 50

  5. ORGANOCHLORINE CHEMICAL RESIDUES IN HERRING GULLS, RING-BILLED GULLS, AND COMMON TERNS OF WESTERN LAKE SUPERIOR

    EPA Science Inventory

    Residues of polychlorinated biphenyls (PCBs), DDE, DDT, and hexachlorobenzene (HCB) were analyzed for three age classes (e.g. pre-fledge muscle and blood, and post-fledge muscle) of the herring gull, ring-billed gull, and common tern for samples collected in the western end of La...

  6. Shoaling of nonlinear internal waves in Massachusetts Bay

    USGS Publications Warehouse

    Scotti, A.; Beardsley, R.C.; Butman, B.; Pineda, J.

    2008-01-01

    The shoaling of the nonlinear internal tide in Massachusetts Bay is studied with a fully nonlinear and nonhydrostatic model. The results are compared with current and temperature observations obtained during the August 1998 Massachusetts Bay Internal Wave Experiment and observations from a shorter experiment which took place in September 2001. The model shows how the approaching nonlinear undular bore interacts strongly with a shoaling bottom, offshore of where KdV theory predicts polarity switching should occur. It is shown that the shoaling process is dominated by nonlinearity, and the model results are interpreted with the aid of a two-layer nonlinear but hydrostatic model. After interacting with the shoaling bottom, the undular bore emerges on the shallow shelf inshore of the 30-m isobath as a nonlinear internal tide with a range of possible shapes, all of which are found in the available observational record. Copyright 2008 by the American Geophysical Union.

  7. Chromosome aberrations and DNA strand breaks in glaucous gull (Larus hyperboreus) chicks fed environmentally contaminated gull eggs.

    PubMed

    Krøkje, Ase; Bingham, Chris; Tuven, Ruth Husmo; Gabrielsen, Geir Wing

    2006-01-01

    In this present laboratory study, our results suggest that a complex mixture of pollutants found in the marine environment exerts genotoxic effects on glaucous gull (Larus hyperboreus) chicks fed environmentally contaminated gull eggs. Chromosome aberrations, quantified by cytogenetic analysis of blood cells, and DNA strand breaks, quantified by agarose gel electrophoresis and image data analysis, were determined in glaucous gull chicks fed environmentally contaminated gull eggs (exposed group) and in chicks fed hen eggs (control group). For both female and male gulls, the fraction of damaged metaphases was quantitatively higher in exposed than in control groups. On the other hand, the differences between the control and the exposed groups were more relevant when the chromosomal aberration data were treated as group totals rather than at the individual level. Consistent results were obtained in the DNA strand break analyses. The control group appeared to display a greater median molecular length (MML) than the exposed group. PMID:16291568

  8. Relationships between ecological variables and four organochlorine pollutants in an artic glaucous gull (Larus hyperboreus) population.

    PubMed

    Bustnes, Jan Ove; Miland, Oystein; Fjeld, Magnus; Erikstad, Kjell Einar; Skaare, Janneche Utne

    2005-07-01

    The Arctic has become a sink for organochlorine contaminants (OCs) from lower latitudes, and relatively high levels have been found in different biota. Recent studies of the glaucous gull, Larus hyperboreus, a top predator in the arctic food web, have documented that high blood residues of various OCs are related to lower reproductive performance and reduced adult survival. Here we provide additional evidence that OCs are having ecological effects in the glaucous gull population at Bear Island in the Norwegian Arctic, and compare the effects of the four major OCs found in the glaucous gulls: HCB, oxychlordane, DDE and PCBs, which made up >95% of measured OCs. Firstly; it has previously been shown that gulls with high levels of PCBs in their blood spent more time away from the nest site during incubation than gulls with low levels. Here we reanalyzed the data and found that PCBs (P<0.02) and oxychlordane (P<0.05) were positive and significantly related to time away from the nest site, while DDE and HCB were not related to this trait. Secondly, among females which bred in an area where fish dominated the diet, and thus had high flight costs during feeding, early chick growth was negatively related to maternal levels of all four OCs, especially HCB and DDE (P<0.01). On the contrary, among females breeding in an area where the diet was dominated by eggs and young from nearby seabird colonies, and thus feeding costs were low, there were no effects of OC levels on early chick growth. This indicates that additional stress may be fundamental in causing reproductive effects of OCs in this population. Finally, during three breeding seasons we examined the probability of adults returning to the breeding grounds in the subsequent season, as a function of blood concentration of the four OCs. Overall, return rate from one year to the next was negatively related to blood residues of oxychlordane (P=0.02), but not significantly related to the other three compounds. Further support for the importance of oxychlordane was that a 60% drop in the blood levels between 1997 and 2000 led to a significant increase in return rate between these two years. PMID:15809119

  9. Shoaling characteristics of the Gulf Intracoastal Waterway in Texas 

    E-print Network

    Atturio, John Michael

    1976-01-01

    was last reported. These two assumptions were made to simplify com- putations. A short example illustrating the above explanation should clarify the procedure used. Example 1. --Computation of Shoaling Rate in the Gulf Intracoastal Waterway from... Rates 10. Predicted Shoaling Rate for Significant Environmental Factors 39 41 42 LIST OF FIGURES 1. Typical Land Cut Section of the Gulf Intracoastal Waterway 2. Total Material Removed From the Waterway by Maintenance Dredging 15 3...

  10. REPORT ON SIX RECENT SIGHTINGS OF THE ICELAND GULL IN NORTH CAROLINA WITH COMMENTS ON PROBLEMS OF FIELD IDENTIFICATION

    Microsoft Academic Search

    JOHN O. FUSSELL; MICHAEL J. TOVE; HARRY E. LeGRAND

    1982-01-01

    Observations of six Iceland Gulls, seen in Carteret and Dare Counties in 1980 and 1981, are discussed. Evidence is presented to show that these gulls were not hybrids, or albinistic or leucistic individuals, or Glaucous or Thayer's Gulls. Separation of Iceland Gull and Thayer's Gull can be difficult and some individuals probably cannot be safely identified. Emphasis is placed on

  11. At-sea behavior varies with lunar phase in a nocturnal pelagic seabird, the swallow-tailed gull

    USGS Publications Warehouse

    Cruz, Sebastian M.; Hooten, Mevin; Huyvaert, Kathryn P.; Proaño, Carolina B.; Anderson, David J.; Afanasyev, Vsevolod; Wikelski, Martin

    2013-01-01

    Strong and predictable environmental variability can reward flexible behaviors among animals. We used long-term records of activity data that cover several lunar cycles to investigate whether behavior at-sea of swallow-tailed gulls Creagrus furcatus, a nocturnal pelagic seabird, varied with lunar phase in the Galápagos Islands. A Bayesian hierarchical model showed that nighttime at-sea activity of 37 breeding swallow-tailed gulls was clearly associated with changes in moon phase. Proportion of nighttime spent on water was highest during darker periods of the lunar cycle, coinciding with the cycle of the diel vertical migration (DVM) that brings prey to the sea surface at night. Our data show that at-sea behavior of a tropical seabird can vary with environmental changes, including lunar phase.

  12. Habitat Suitability Index Models: Laughing Gull

    USGS Publications Warehouse

    Zale, Alexander V.; Mulholland, Rosemarie

    1985-01-01

    A review and synthesis of existing information were used to develop a habitat model for laughing gull (Larus atricilla). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1.0 (optimally suitable habitat) for areas along the Gulf of Mexico coast. Habitat suitability indices are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for application of the model and techniques for measuring model variables are described.

  13. SEDIMENT BUDGET: MISSISSIPPI SOUND BARRIER ISLANDS* MARK R. BYRNES1

    E-print Network

    US Army Corps of Engineers

    and is occupied by the Pascagoula Ship Channel with a regularly maintained channel depth and width. Dog Keys of about 430,000 cy/yr throughout the barrier island system. Dog Keys Pass, located updrift of East Ship two active channels and ebb shoals. As such, a deficit of sand exists along East Ship Island. Littoral

  14. Sea-floor character and sedimentary processes of Great Round Shoal Channel, offshore Massachusetts

    USGS Publications Warehouse

    Poppe, Lawrence J.; Ackerman, Seth D.; Foster, David S.; Blackwood, Dann S.; Williams, S. Jeffress; Moser, M.S.; Stewart, H.F.; Glomb, K.A.

    2007-01-01

    The imagery, interpretive data layers, and data presented herein were derived from multibeam echo-sounder and sidescan-sonar data collected in the vicinity of Great Round Shoal Channel, the main passage through shoals located at the eastern entrance to Nantucket Sound, Massachusetts, and from the stations occupied to verify these acoustic data (fig. 1). Basic data layers show sea-floor topography, sun-illuminated shaded relief, and backscatter intensity; interpretive layers show the distributions of surficial sediment, sedimentary environments, and sea-floor features. Presented verification data include sediment grain-size analyses and a gallery of still photographs of the seabed. The multibeam and sidescan data, which together cover an approximately 39.9-km² area of sea floor, were collected during National Oceanic and Atmospheric Administration (NOAA) hydrographic survey H11079 (fig. 1). Although originally collected for charting purposes, these data provide a fundamental framework for research and management activities along this part of the Massachusetts coastline (Noji and others, 2004), show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. This publication is the third in a series of U.S. Geological Survey (USGS) digital reports describing the sea-floor geology around Cape Cod. The first focused on the area off the eastern shore of the outer Cape (Poppe and others, 2006); the second on a passage through the Elizabeth Islands (Poppe and others, 2007).

  15. Shoaling develops with age in Zebrafish (Danio rerio)

    PubMed Central

    Buske, Christine; Gerlai, Robert

    2010-01-01

    The biological mechanisms of human social behavior are complex. Animal models may facilitate the understanding of these mechanisms and may help one to develop treatment strategies for abnormal human social behavior, a core symptom in numerous clinical conditions. The zebrafish is perhaps the most social vertebrate among commonly used laboratory species. Given its practical features and the numerous genetic tools developed for it, it should be a promising tool. Zebrafish shoal, i.e. form tight multimember groups, but the ontogenesis of this behavior has not been described. Analyzing the development of shoaling is a step towards discovering the mechanisms of this behavior. Here we study age-dependent changes of shoaling in zebrafish from day 7 post fertilization to over 5 months of age by measuring the distance between all pairs of fish in freely swimming groups of ten subjects. Our longitudinal (repeated measure within subject) and cross sectional (non-repeated measure between subject) analyses both demonstrated a significant increase of shoaling with age (decreased distance between shoal members). Given the sophisticated genetic and developmental biology methods already available for zebrafish, we argue that our behavioral results open a new avenue towards the understanding of the development of vertebrate social behavior and of its mechanisms and abnormalities. PMID:20837077

  16. Expansion of the Mediterranean Gull Larus melanocephalus in Poland

    Microsoft Academic Search

    Monika Zieli?ska; Piotr Zieli?ski; Pawe? Ko?odziejczyk; Pawe? Szewczyk; Jacek Betleja

    2007-01-01

    Since 1981, when the first breeding pair of Mediterranean Gull Larus melanocephalus was recorded in Poland, the population of this gull has increased considerably. Its population size was stable until 1997,\\u000a not exceeding ten pairs annually; thereafter, an increasing number of sightings were made, and during the last 5 years between\\u000a 26 and 39 breeding pairs have been recorded in Poland.

  17. Diversity patterns in helminth communities in common gulls, Larus canus.

    PubMed

    Kennedy, C R; Bakke, T A

    1989-06-01

    The parameters of species richness, abundance and diversity of the intestinal helminth infracommunities of a sample of 269 Common gulls, Larus canus, were examined over one season at Agdenes, Norway. The communities developed rapidly in unfledged gulls and the diversity parameters were of similar magnitude in immature and adult birds. All parameters were low in the early part of the season, reached maxima in June or July and fluctuated erratically or declined thereafter. Comparison of summary parameters with those from other species of gulls indicated that helminth community diversity in Common gulls is fairly typical of gulls in general. in gulls as a group, helminth communities show common features of high species richness, low abundance, few or no core species and a number of species that occur rarely and in low numbers. Expectations of particularly high parasite community diversity were not fully realised because species lists and diversity of the component community are not a very good basis for predicting diversity at the infracommunity level. PMID:2771449

  18. The herring gull Larus argentatus as a carrier of salmonella.

    PubMed

    Butterfield, J; Coulson, J C; Kearsey, S V; Monaghan, P; McCoy, J H; Spain, G E

    1983-12-01

    The proportion of salmonella carriers among town-nesting herring gulls increased significantly from 2.1% in 1975-6 to 8.4% in 1979. The range of serotypes carried by herring gulls was similar to that causing infection in man, and it is likely that the gulls ingest these serotypes when feeding at untreated sewage outfalls on the coast. This is supported by the proportion of salmonella carriers being higher among first-year birds (9.7%) than among older birds (2.0%), as it is known that higher proportions of immature herring gulls feed on the coast. Herring gulls carrying salmonellas appeared healthy at the time of capture and at a later date it was assumed that they were not themselves infected. However, their habit of congregating in large numbers on reservoirs and rubbish tips and also at resting sites on farmland often far from feeding and roosting areas, multiplies the pollution problem and increases the potential health hazard for both man and farm stock. Herring gulls feed at a variety of sites and fly many miles from food source to food source and from feeding areas to the roost. Thus, even within the same day, there is the possibility of the transfer of salmonellas over a much wider area than previously considered. PMID:6663058

  19. The herring gull Larus argentatus as a carrier of salmonella.

    PubMed Central

    Butterfield, J.; Coulson, J. C.; Kearsey, S. V.; Monaghan, P.; McCoy, J. H.; Spain, G. E.

    1983-01-01

    The proportion of salmonella carriers among town-nesting herring gulls increased significantly from 2.1% in 1975-6 to 8.4% in 1979. The range of serotypes carried by herring gulls was similar to that causing infection in man, and it is likely that the gulls ingest these serotypes when feeding at untreated sewage outfalls on the coast. This is supported by the proportion of salmonella carriers being higher among first-year birds (9.7%) than among older birds (2.0%), as it is known that higher proportions of immature herring gulls feed on the coast. Herring gulls carrying salmonellas appeared healthy at the time of capture and at a later date it was assumed that they were not themselves infected. However, their habit of congregating in large numbers on reservoirs and rubbish tips and also at resting sites on farmland often far from feeding and roosting areas, multiplies the pollution problem and increases the potential health hazard for both man and farm stock. Herring gulls feed at a variety of sites and fly many miles from food source to food source and from feeding areas to the roost. Thus, even within the same day, there is the possibility of the transfer of salmonellas over a much wider area than previously considered. PMID:6663058

  20. Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode

    E-print Network

    Wisenden, Brian D.

    Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode cercariae benefits of shoaling in fathead minnows exposed to larvae (cercariae) of two of their most common species should favour the evolution of cercariae-avoidance behaviours. 3. We evaluated shoal dimensions in groups

  1. Comparison of Helicobacter spp. genetic sequences in wild and captive seals, and gulls.

    PubMed

    Oxley, Andrew P A; McKay, David B

    2005-06-01

    Helicobacter species are widely distributed in the gastrointestinal system of humans and many animal taxa. Investigations of natural infections are essential to elucidating their role within the host. The feces of fur seals Arctocephalus pusillus doriferus and sea lions Neophoca cinerea from 3 separate captive populations, as well as a wild colony from Kangaroo Island, Australia, were examined for the occurrence of Helicobacter spp. The feces from several wild silver gulls Larus novahollandiae were also investigated. As detected by PCR, 18 of 21 samples from captive and 12 of 16 samples from wild seals were positive for Helicobacter spp. Three species were identified in these animals. Whilst one possibly novel type was identified from wild fur seals, the majority of wild and captive individuals had the same species. This species also occurred in more than 1 seal type and in silver gulls, and shared a 98.1 to 100% identity to other Helicobacter spp. from harp seals and sea otters. A similar sequence type to species identified from cetaceans was also detected in several captive seals. This study reports for the first time the presence of Helicobacter spp. in wild and captive seals and demonstrates the diversity and broad-host range of these organisms in the marine host. PMID:16060262

  2. Circumpolar contamination in eggs of the high-arctic ivory gull Pagophila eburnea.

    PubMed

    Lucia, Magali; Verboven, Nanette; Strøm, Hallvard; Miljeteig, Cecilie; Gavrilo, Maria V; Braune, Birgit M; Boertmann, David; Gabrielsen, Geir W

    2015-07-01

    The ivory gull Pagophila eburnea is a high-Arctic species threatened by climate change and contaminants. The objective of the present study was to assess spatial variation of contaminant levels (organochlorines [OCs], brominated flame retardants [BFRs], perfluorinated alkyl substances [PFASs], and mercury [Hg]) in ivory gulls breeding in different areas across the Arctic region as a baseline for potential future changes associated with climate change. Contaminants were already determined in eggs from Canada (Seymour Island; except PFASs), Svalbard in Norway (Svenskøya), and 3 sites in Russia (Nagurskoe, Cape Klyuv, and Domashny). New data from Greenland allowed the investigation of a possible longitudinal gradient of contamination. The most quantitatively abundant OCs were p,p'-dichlorodiphenyldichloroethylene (DDE) and polychlorobiphenyls. Mercury concentrations were higher in Canada compared with other colonies. Eggs from Nagurskoe often were characterized by higher OC and BFR concentrations. Concentrations gradually decreased in colonies situated east of Nagurskoe. In contrast, PFAS concentrations, especially perfluorooctanoate and perfluorononanoate, were higher in Greenland. Some of the contaminants, especially Hg and p,p'-DDE, exceeded published thresholds known to disrupt the reproductive success of avian species. Overall, the levels of OCs, BFRs, and PFASs did not suggest direct lethal exposure to these compounds, but their potential synergetic/additive sublethal effects warrant monitoring. Environ Toxicol Chem 2015;34:1552-1561. © 2015 SETAC. PMID:25677940

  3. 77 FR 43805 - Gull Hazard Reduction Program at John F. Kennedy International Airport; Record of Decision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-26

    ...Docket No. APHIS-2006-0035] Gull Hazard Reduction Program at...environmental impact statement for the Gull Hazard Reduction Program at...and Independence Avenue SW., Washington, DC. Normal reading room hours...action is a supplement to the Gull Hazard Reduction Program...

  4. Validation Analysis of the Shoal Groundwater Flow and Transport Model

    Microsoft Academic Search

    Ahmed Hassan; Jenny Chapman

    2008-01-01

    Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical

  5. TECHNICAL REPORT SERIES Internal waves and internal solitones shoaling

    E-print Network

    Thiem, Øyvind

    BCCS TECHNICAL REPORT SERIES Internal waves and internal solitones shoaling and breaking along Deliverence to Norsk Hydro. Internal waves. Contract number 5294251 UNIFOB the University of Bergen research it is investigated if internal waves or internal solitons can lead to the measured events. Since these kind of waves

  6. Shoaling internal solitary waves B. R. Sutherland,1,2

    E-print Network

    Sutherland, Bruce

    Shoaling internal solitary waves B. R. Sutherland,1,2 K. J. Barrett,1 and G. N. Ivey3 Received 29, 1844]. Within estuaries and the coastal oceans, internal sol- itary waves are manifest as large for their (admit- tedly relatively small) contribution to ocean mixing on a global scale, internal solitary waves

  7. Incipient Sediment Movement by Shoaling Internal Gravity Waves

    Microsoft Academic Search

    D. A. Cacchione; J. B. Southard

    1974-01-01

    criterion for incipient movement of bottom sediment by shoaling internal waves by equating moments due to fluid force and gravity force acting on an exposed bed particle. Comparison of predicted conditions of incipient sediment movement with mean sediment sizes actually present on the continental shelf and continental slope southeast of New England indicates that shoreward propagation of relatively high frequency

  8. Incipient motion of coarse particles under regular shoaling waves

    Microsoft Academic Search

    Emanuele Terrile; Ad J. H. M. Reniers; Marcel J. F. Stive; Maarten Tromp; Henk Jan Verhagen

    2006-01-01

    Incipient motion of coarse particles under regular shoaling waves is examined. Experiments are performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth, combinations of similar peak orbital velocities and weak to strong intra-wave accelerations were created. The particles used in these experiments have two different sizes both

  9. Plastic consumption and diet of Glaucous-winged Gulls (Larus glaucescens).

    PubMed

    Lindborg, Valerie A; Ledbetter, Julia F; Walat, Jean M; Moffett, Cinamon

    2012-11-01

    We analyzed dietary habits and presence of plastic in 589 boluses of Glaucous-winged Gulls (Larus glaucescens) as one of two studies on the impact of plastics on marine life in the US Salish Sea. Volunteers dissected boluses collected (2007-2010) from Protection Island, Washington. Components were separated into 23 food and non-food categories. Plastic was found in 12.2% of boluses, with plastic film being the most common plastic form. No diet specialization was observed. Vegetation was the most abundant component, found in 91.3% of boluses. No relationship was observed between any dietary items and occurrence or type of plastic found. Load and potential ecological impact in the marine environment can be expected to increase concurrently with increasing plastic use and number and variety of plastic sources. Future studies are necessary to understand the impacts of plastic ingestion on this species. PMID:22995785

  10. Distribution, diet and habitat selection by four sympatrically breeding gull species in the south-eastern North Sea

    Microsoft Academic Search

    U. Kubetzki; S. Garthe

    2003-01-01

    Food choice, feeding habitat use and spatial distribution of black-headed gulls ( Larus ridibundus), mew gulls ( L. canus), herring gulls ( L. argentatus) and lesser black-backed gulls ( L. fuscus) were studied in the south-eastern North Sea. At-sea distribution during the breeding period was assessed by transect counts from ships. Clear differences could be established between the four species,

  11. Aspects of hatching success and chick survival in Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Eyler, T.B.; Erwin, R.M.; Stotts, D.B.; Hatfield, J.S.

    1999-01-01

    Because of a long-term population decline in Gull-billed Terns (Sterna nilotica) nesting along the coast of Virginia, we began a three year study in 1994 to monitor hatching success and survival of Gull-billed Tern chicks at several Virginia colony sites. Colonies were located on either small, storm-deposited shellpiles along marsh fringes or large, sandshell overwash fans of barrier islands. Nests were monitored one to three times a week for hatching success, and enclosures were installed around selected nests to monitor chick survival from hatching to about two weeks of age. Hatching success was lower in marsh colonies than island colonies, and was lower in 1995 than in 1994 and 1996, primarily because of flooding. The average brood size of nests where at least one chick hatched was 1.99 chicks. Survival rates of chicks to 14 days depended on hatch order and year but not brood size (one vs. two or more) or time of season. A-chicks had higher survival rates than B-chicks and third-hatched C-chicks (0.661 compared to 0.442 and 0.357, respectively). The year effect was significant only for A-chicks, with lower survival in 1994 (0.50) than in 1995 (0.765) or 1996 (0.758). Overall, productivity was low (0.53 chick per nest) compared to estimates for colonies in Denmark, and was attributable to nest flooding by spring and storm-driven high tides and chick predation, presumably mostly by Great Horned Owls (Bubo virginianus).

  12. [A comparative analysis of the helminth fauna of kittiwake Rissa tridactyla (Linnaeus, 1758) and glaucous gull Larus hyperboreus Gunnerus, 1767 from different parts of the Barents Sea].

    PubMed

    Kuklin, V V; Galaktionov, K V; Galkin, A K; Marasaev, S F

    2005-01-01

    The article is based on the results of helminthological observations made on kittiwake Rissa tridactyla and glaucous gull Larus hyperboreus in 1991-2001 in different areas of the Barents Sea (Eastern Murman coast, Franz Josef Land, Novaya Zemlya, Spitzbergen). 18 helminth species (2 trematodes, 11 cestodes, 4 nematodes, and 2 acanthocephalans) were recorded in the kittiwakes and 19 (3 trematodes, 9 cestodes, 5 nematodes and 2 acanthocephalans) species were recorded in the glaucous gulls. Trematodes were absent in the birds collected at the Franz Josef Land and the northern island of Novaya Zemlya. 3 trematode species, namely Gymnophallus sp. (somateria?), Microphallus sp. 1 (M. pseudopygmaeus), and Cryptocotyle lingua were found in the glaucous gulls of western Spitzbergen. It was supposed that the life cycles of these parasites can be completed there. On the other hand, coastal ecosystems of Arctic archipelagoes turn out to be favourable for the transmission of some cestodes. This is closely connected with the regional traits in the marine bird diet, namely the increase of the amphipod (intermediate hosts of hymenolepidids and some dilepidids) and polar cod (supposed second intermediate host for some tetrabothriids) portion in Arctic. As a result, cestodes are the base of the helminth fauna of kittiwakes and glaucous gulls of the Barents Sea, by their species richness, prevalence and abundance. Nematodes and acanthocephalans were represented by a few species with low infection intensity. The main ecological factors affected the regional difference in the species richness and abundance of the helminths parasitising kittiwakes and glaucous gulls in the Barents Sea are proposed. Those are regional climatic features and regional traits in the behaviour and food priorities of birds, and also the distribution of the helminths intermediate hosts, invertebrates and fishes. The phenomenon of host specificity lowering with respect to the definitive host was recorded in some cestode species (Microsomacanthus diorchis, M. microsoma, and Arctotaenia tetrabothrioides) on the border of their distribution ranges, the coastal ecosystems of Arctic. PMID:16396393

  13. Cytochrome P4501A induction and DNA adduct formation in glaucous gulls (Larus hyperboreus), fed with environmentally contaminated gull eggs.

    PubMed

    Østby, Lene; Gabrielsen, Geir Wing; Krøkje, Ase

    2005-11-01

    This study indicates that complex mixtures of pollutants found in the Arctic marine environment have genotoxic effects in glaucous gulls (Larus hyperboreus). DNA adducts were quantified, by the (32)P-postlabeling technique, in liver samples from gulls fed with hen eggs (controls) and from gulls fed with environmentally contaminated gull eggs (exposed). All birds were grown and fed under laboratory conditions. Hepatic homologues to mammalian cytochrome P4501A (CYP1A) proteins were also determined by Western blotting. DNA adducts were detected in all but one liver sample, but the exposed birds had a significantly increased level of DNA adducts relative to that of the controls. There was no clear significant correlation between the DNA adduct level and the level of organochlorine compounds (OCs) in blood. The level of CYP1A protein was significantly higher in the liver of exposed male gulls than in the liver of control males and positively correlated, with significance, to the level of OC compounds measured in blood. There was no significant correlation between the level of DNA adducts and the CYP1A protein content. PMID:16216630

  14. Fraser Island Lady Elliot Island

    E-print Network

    Wang, Yan

    Hinchinbrook Island Lizard Island Double Island Green Island Fitzroy Island North and South Stradbroke Islands Moreton Island GOLD COAST Gulf of Carpenteria Thursday Island Torres Strait Horn Island Maroochydore

  15. Size-assortative shoaling in fish: the effect of oddity on foraging behaviour

    PubMed

    Peuhkuri

    1997-08-01

    Current theory predicts that fish should show size-assortative shoaling in order to avoid increased predation risk by being the odd one out (oddity effect), or in order to minimize competition for food. I investigated with three-spined sticklebacks, Gasterosteus aculeatusthe importance of the oddity effect in promoting size-assortative shoaling. The greater an individual assesses its predation risk the less actively it is likely to forage. Hence, I examined with small and large fish whether an individual's foraging activity depends on its appearance (size) in relation to that of others in a shoal. The shoals were composed of three, six and 12 fish. Either one individual deviated in size from the rest of the shoal members or all the fish in a shoal were of similar size. When a stickleback was larger than others in the shoal its foraging activity was lower than that of large individuals in a shoal dominated by large fish or those in a size-assorted shoal. Small sticklebacks, however, did not change their foraging activity on the basis of their appearance in a shoal. These responses of individuals to their appearance did not depend on shoal size nor on the presence or absence of a predator. The results suggest that the oddity effect is likely to prevent larger sticklebacks from joining shoals of smaller individuals. They also suggest that factors other than the oddity effect, potentially food competition, may be more important in leading individuals to avoid the company of larger ones and prefer shoaling with matching conspecifics. PMID:9268457

  16. THE BIRDS OF SEYMOUR ISLAND, ANTARCTICA

    Microsoft Academic Search

    Diego Montalti; Guillermo E. Soave

    During January-February 2000, we obtained information on the abundance and distribution of seabirds in Seymour Island, Antarctica. Six species breed in this area: Adélie Penguin (Pygoscelis adeliae; 28,255 pairs), Wilson's Storm-petrel (Oceanites oceanicus; 22), Brown Skua (Catharacta antarctica; 30), South Polar Skua (C. maccormicki; 33), Kelp Gull (Larus dominicanus; 296) and Antarctic Tern (Sterna vittata; 107). In addition, five non-breeding

  17. Incipient motion of coarse particles under regular shoaling waves

    Microsoft Academic Search

    E. Terrile; A. J. H. M. Reniers; M. J. F. Stive; M. Tromp; H. J. Verhagen

    2005-01-01

    Incipient motion of coarse particles under regular shoaling waves is examined. Experiments are performed to investigate the effects of bed fluid acceleration on coarse particle stability. By varying wave height, wave period and water depth, combinations of similar peak orbital velocities and\\u000aweak to strong intra-wave accelerations were created. The particles used in these experiments have two different sizes both

  18. Pleistocene barrier bar seaward of ooid shoal complex near Miami, Florida

    USGS Publications Warehouse

    Halley, Robert B.; Shinn, Eugene A.; Hudson, J. Harold; Lidz, Barbara H.

    1977-01-01

    An ooid sand barrier bar of Pleistocene age was deposited along the seaward side of an ooid shoal complex southwest of Miami, Florida. The bar is 35 km long, about 0.8 km wide, elongate parallel with the trend of the ooid shoal complex and perpendicular to channels between individual shoals. A depression 1.6 km wide, interpreted as a back-barrier channel, isolates the bar from the ooid shoals. During sea-level fall and subaerial exposure of the bar, the ooid sand was cemented in place, preventing migration of the barrier. No Holocene analogue of this sand body is recognized, perhaps because of the relative youthfulness of Holocene ooid shoals. This Pleistocene ooid shoal complex, with its reservoir-size barrier bar, may serve as a refined model for exploration in ancient ooid sand belts.

  19. Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode cercariae.

    PubMed

    Stumbo, Anthony D; James, Clayton T; Goater, Cameron P; Wisenden, Brian D; Cotter, Sheena

    2012-11-01

    1. Individuals that live in groups benefit from increased foraging success and decreased predation. Protection from some types of parasites may provide an additional benefit of group-living. For fish, the extent to which shoaling can reduce an individual's risk of exposure to the infective stages of parasites is unknown. 2. We tested for antiparasite benefits of shoaling in fathead minnows exposed to larvae (cercariae) of two of their most common species of trematode, Ornithodiplostomum ptychocheilus and Posthodiplostomum minimum. As developing stages (metacercariae) of these trematodes cause reductions in minnow activity, growth and survival, natural selection should favour the evolution of cercariae-avoidance behaviours. 3. We evaluated shoal dimensions in groups of minnows exposed to O. ptychocheilus and to other chemical/physical stimuli within aquaria. To compare risk of exposure in shoaling vs. non-shoaling fish, we confined groups of minnows into mesh cages in outdoor mesocosms, exposed them to cercariae, then compared mean worm numbers in grouped vs. solitary fish. Lastly, we tested whether fish located within the centre of an artificial shoal reduced their risk of cercariae exposure compared with those along peripheral edges. 4. Minnows distinguished infective cercariae from other potential aquatic threats and responded with activity that reduced the 2-dimensional area of their shoals 15-fold compared with water-only controls. Fish confined within artificial shoals had 3-fold fewer worms than single fish and minnows located within the centre of artificial shoals had significantly fewer worms than those without peripheral minnows. 5. These results show that shoaling reduces a minnows' risk of exposure to cercariae, either directly via detection of cercariae in the water column followed by behavioural avoidance or indirectly via behaviour-mediated differences in exposure between shoaling vs. non-shoaling fish. PMID:22774840

  20. The herring gull complex is not a ring species.

    PubMed

    Liebers, Dorit; de Knijff, Peter; Helbig, Andreas J

    2004-05-01

    Under what circumstances speciation in sexually reproducing animals can occur without geographical disjunction is still controversial. According to the ring-species model, a reproductive barrier may arise through 'isolation by distance' when peripheral populations of a species meet after expanding around some uninhabitable barrier. The classical example of this kind of speciation is the herring gull (Larus argentatus) complex, with a circumpolar distribution in the Northern Hemisphere. Based on mitochondrial DNA variation among 21 gull taxa, we show that members of this complex differentiated largely in allopatry following multiple vicariance and long-distance-colonization events, not primarily through isolation by distance. Reproductive isolation evolved more rapidly between some lineages than between others, irrespective of their genetic distance. Extant taxa are the result of divergent as well as reticulate evolution between two ancestral lineages originally separated in a North Atlantic refugium and a continental Eurasian refugium, respectively. Continental birds expanded along the entire north Eurasian coast and via Beringia into North America. Contrary to the ring-species model, we find no genetic evidence for a closure of the circumpolar ring through colonization of Europe by North American herring gulls. However, closure of the ring in the opposite direction may be imminent, with lesser black-backed gulls about to colonize North America. PMID:15255043

  1. Ingestion of crude oil: sublethal effects in herring gull chicks.

    PubMed

    Miller, D S; Peakall, D B; Kinter, W B

    1978-01-20

    A single small oral dose of Kuwait or South Louisiana crude oil caused cessation of growth, osmoregulatory impairment, and hypertrophy of hepatic, adrenal, and nasal gland tissue in herring gull chicks living in a simulated marine environment. These findings suggest that ingesting crude oil causes multiple sublethal effects that might impair a bird's ability to survive at sea. PMID:145655

  2. Skull deformity in a herring gull chick (Larus argentatus).

    PubMed

    Threlfall, W; Roy, N A

    1988-01-01

    A skull deformity resulting in death of a herring gull chick (Larus argentatus) is described in detail. The bones of the skull and upper jaw were twisted, asymmetrical and of unusual size or absent. The lower jaw had an almost "spoon-like" external appearance and lacked normal articular surfaces. PMID:3352082

  3. Immune Function and Organochlorine Pollutants in Arctic Breeding Glaucous Gulls

    Microsoft Academic Search

    J. O. Bustnes; S. A. Hanssen; I. Folstad; K. E. Erikstad; D. Hasselquist; J. U. Skaare

    2004-01-01

    Organochlorine contaminants (OCs) are known to affect the immune systems of wildlife, and in this study we assessed the relationship between blood concentration of different OCs and measurements relevant to immune status and function in arctic breeding glaucous gulls ( Larus hyperboreus). In 1997 and 2001, we counted white blood cells (heterophils and lymphocytes) from blood smears, and in 2000

  4. The cost of reproduction in the glaucous-winged gull

    Microsoft Academic Search

    W. V. Reid

    1987-01-01

    Experimental enlargement of brood size in the glaucous-winged gull (Larus glaucescens) resulted in increased adult foraging time, decreased adult body weight at the end of the breeding season, and decreased over-winter adult survival. The decreased survival of breeding adults was associated with reduced body condition at the end of breeding (resulting from physiological costs of reproduction). Decreased survival was not

  5. Reproductive investment and parental roles in Sabine's gulls Xema sabini

    Microsoft Academic Search

    Iain J. Stenhouse; H. Grant Gilchrist; William A. Montevecchi

    2004-01-01

    More than 90% of avian species exhibit biparental care, though parental activities are often shared unequally between the members of a pair. Among gull species ( Laridae), males and females generally share parental activities, although there appear to be considerable differences between species in the relative contribution of each sex. This study examined the behaviour of male and female Sabine's

  6. Phylogenetic Diversity and Molecular Detection of Bacteria in Gull Feces

    EPA Science Inventory

    In spite of increasing public health concerns about the potential risks associated with swimming in waters contaminated with waterfowl feces, little is known about the composition of the gut microbial community of aquatic birds. To address this, a gull 16S rDNA fecal clone librar...

  7. IDENTIFICATION AND MOLT OF HYBRID GLAUCOUS-WINGED GULLS

    Microsoft Academic Search

    JON R. KING; STEVE N. G. HOWELL; Shoreline Highway

    1998-01-01

    unpublished data), with the Herring (L. argentatus srnithsonianus) in southern Alaska (Williamson and Peyton 1963, Patten and Weisbrod 1974), and with the Glaucous (L. hyperboreus) in western Alaska (Strang 1977). Probably nowhere else in the world do hybrids constitute such a large proportion of the total gull population as along the west coast of North America. Consequently, birders in this

  8. Characterization of AhR agonists reveals antagonistic activity in European herring gull (Larus argentatus) eggs.

    PubMed

    Muusse, Martine; Christensen, Guttorm; Gomes, Tânia; Ko?an, Anton; Langford, Katherine; Tollefsen, Knut Erik; Va?ková, Lenka; Thomas, Kevin V

    2015-05-01

    European herring gull (Larus argentatus) eggs from two Norwegian islands, Musvær in the south east and Reiaren in Northern Norway, were screened for dioxins, furans, and dioxin-like and selected non-dioxin-like polychlorinated biphenyls (PCBs), and subjected to non-target analysis to try to identify the aryl hydrocarbon receptor (AhR) agonists, responsible for elevated levels measured using the dioxin responsive chemically activated luciferase expression (DR-CALUX) assay. Eggs from Musvær contained chemically calculated toxic equivalent (WHO TEQ) levels of between 109 and 483 pg TEQ/g lw, and between 82 and 337 pg TEQ/g lw was determined in eggs from Reiaren. In particular PCB126 contributed highly to the total TEQ (69-82%). In 19 of the 23 samples the calculated WHO TEQ was higher than the TEQCALUX. Using CALUX specific relative effect potencies (REPs), the levels were lower at between 77 and 292 pg/g lw in eggs from Musvær and between 55 and 223 pg/g lw in eggs from Reiaren, which was higher than the TEQCALUX in 16 of the 23 samples. However, the means of the REP values and the TEQCALUX were not significantly different. This suggests the presence of compounds that can elicit antagonist effects, with a low binding affinity to the AhR. Non-target analysis identified the presence of hexachlorobenzene (HCB) (quantified at 9.6-185 pg/g lw) but neither this compound nor high concentrations of PCB126 and non-dioxin-like PCBs could explain the differences between the calculated TEQ or REP values and the TEQCALUX. Even though, for most AhR agonists, the sensitivity of herring gulls is not known, the reported levels can be considered to represent a risk for biological effects in the developing embryo, compared to LC50 values in chicken embryos. For human consumers of herring gull eggs, these eggs contain TEQ levels up to four times higher than the maximum tolerable weekly intake. PMID:25666281

  9. Comparison of Gull Feces-Specific Assays Targeting the 16S rRNA Genes of Catellicoccus marimammalium and Streptococcus spp.

    PubMed Central

    Ryu, Hodon; Griffith, John F.; Khan, Izhar U. H.; Hill, Stephen; Edge, Thomas A.; Toledo-Hernandez, Carlos; Gonzalez-Nieves, Joel

    2012-01-01

    Two novel gull-specific quantitative PCR (qPCR) assays were developed using 16S rRNA gene sequences from gull fecal clone libraries: a SYBR green assay targeting Streptococcus spp. (gull3) and a hydrolysis TaqMan assay targeting Catellicoccus marimammalium (gull4). The objectives of this study were to compare the host specificity of a previous C. marimammalium qPCR assay (gull2) with that of the new markers and to examine the presence of the three gull markers in environmental water samples from different geographic locations. Most of the gull fecal samples tested (n = 255) generated positive signals with the gull2 and gull4 assays (i.e., >86%), whereas only 28% were positive with gull3. Low prevalence and abundance of tested gull markers (0.6 to 15%) were observed in fecal samples from six nonavian species (n = 180 fecal samples), whereas the assays cross-reacted to some extent (13 to 31%) with other (nongull) avian fecal samples. The gull3 assay was positive against fecal samples from 11 of 15 avian species, including gull. Of the presumed gull-impacted water samples (n = 349), 86%, 59%, and 91% were positive with the gull2, the gull3, and the gull4 assays, respectively. Approximately 5% of 239 non-gull-impacted water samples were positive with the gull2 and the gull4 assays, whereas 21% were positive witg the gull3 assay. While the relatively high occurrence of gull2 and gull4 markers in waters impacted by gull feces suggests that these assays could be used in environmental monitoring studies, the data also suggest that multiple avian-specific assays will be needed to accurately assess the contribution of different avian sources in recreational waters. PMID:22226950

  10. Adoption of chicks and the level of relatedness in common gull, Larus canus, colonies: DNA fingerprinting analyses.

    PubMed

    Bukaciński; Bukacińska; Lubjuhn

    2000-02-01

    In common gull colonies on islands of the Vistula River, Poland, adoption of chicks is common. In 1997, we observed 81 chicks from 35 nests. Of these, 19 (23.4%) left their natal broods and were adopted by other pairs. Another 11 (31.4%) were driven from the foreign territory by the owners. Foreign chicks were adopted by 15 pairs (42.9%). Eleven pairs (31.4%) drove foreign chicks from the territory. To test if the frequent adoptions in these colonies could be explained by kin selection or the occurrence of kin groups, we calculated band-sharing coefficients and genetic relatedness (r) between interacting birds (neighbours and non-neighbours). Adults that adopted were most often neighbours of the biological parents of adopted chicks, whereas spatially segregated birds, nesting further away, usually drove off the chicks. Band-sharing coefficients between males, but not females, were higher with decreasing internest distances. The band-sharing coefficients for adopted chicks and foster parents were significantly higher than for adopted chicks and randomly selected, spatially segregated pairs from the same and another colony. Band-sharing coefficients of adopted chicks and adopting neighbours (males: r=0.20; females: r=0.16) also tended to be higher than those of rejected chicks and rejecting neighbours (both sexes: r=0.08). Our results suggest that kin groups of neighbours do occur in common gull colonies. Such social structure might lead to indirect inclusive fitness benefits of adopting pairs. Differences in genetic similarity between chicks and adopting or rejecting neighbours show that at least in common gulls we should consider kin altruism as a factor in adoptions. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10675251

  11. Genetic Affinities Within the Herring Gull Larus argentatus Assemblage Revealed by AFLP Genotyping

    Microsoft Academic Search

    Peter de Knijff; Frank Denkers; Norman D. van Swelm; Martin Kuiper

    2001-01-01

    :   To date, the taxonomic status of circumpolar breeding populations of the Herring Gull Larus argentatus, the Lesser Black-backed Gull Larus fuscus, and the closely related Yellow-legged Gull Larus cachinnans has been based on differences or similarities in phenotype, morphology, and feeding and premating behavior. To shed some\\u000a new light on the many taxonomic uncertainties surrounding these taxa, we describe

  12. [Hematologic and hematochemical characteristics of the herring gull (Larus argentatus) and the buzzard (Buteo buteo)].

    PubMed

    Bini, P P; Floris, B; Nuvole, P; Pau, S; Zedda, M T

    1989-09-01

    Some hematological and hematochemical parameters in eight herring gulls (Larus argentatus) and in six buzzards (Buteo buteo) were checked. The buzzards were fed with ovine meat exclusively, while the herring gulls were fed with fish and ovine meat. Considerable differences between the two species were noted, particularly as far as the hematological and lipidic parameters are concerned. These differences are probably related to the aquatic life of the herring gull. PMID:2627341

  13. Upward-shoaling cycles in Smackover carbonates of southwest Alabama

    SciTech Connect

    Kopaska-Merkel, D.C.; Mann, S.D. (Geological Survey of Alabama, Tuscaloosa, AL (United States))

    1993-09-01

    Upper Smackover strata in Alabama commonly consist of one or more upward-shoaling cycles about 15 to 50 ft (3 to 16 m) in thickness. Multiple forcing functions (eustasy, regional tilting, salt halokinesis, and autogenic migration of facies) and varying water depths at the start and end of each upward-shoaling cycle generated an array of sedimentary responses. The Brittain No. 1 well, Permit No. 2478, Healing Springs field, Washington County, Alabama, illustrates nucleation of an offshore bar. Bar deposits are capped by anhydritic sabkha deposits, gradationally overlain by subtidal lagoonal strata. Varying rates (and directions ) of halokinesis controlled this succession. Locally varying rates of salt movement created as many as five sabkha-capped cycles in this area. The International Paper company 20-5 Mo. 1 well, Permit No. 5242, Blacksher field, Baldwin County, Alabama, contains three upward-shoaling cycles capped by evaporites. Limited aggradational potential of supratidal evaporitic settings permitted subsidence-caused immersion, which eventually permitted reactivation of the carbonate factory and formation of the next cycle. The Chatom Unit 20-14 No. 1-04 well, Permit No. 7044, Chatom field, Washington County, contains three different cycles. The lower cycle consists of subtidal lime mudstone, capped by a 5-ft (1.5-m) thick soil zone that contains multiple exposure surfaces, tepee structures, and anhydrite pseudomorphs after lenticular gypsum crystals. The soil zone underlies an intraclastic storm deposit followed by a deepening-upward lagoonal succession. A thin ooid grainstone containing exposure surfaces caps the middle cycle. In the upper cycle, peritidal carbonate strata underlie sabkha deposits.

  14. Genetic affinities within the herring gull Larus argentatus assemblage revealed by AFLP genotyping.

    PubMed

    de Knijff P; Denkers, F; van Swelm, N D; Kuiper, M

    2001-01-01

    To date, the taxonomic status of circumpolar breeding populations of the Herring Gull Larus argentatus, the Lesser Black-backed Gull Larus fuscus, and the closely related Yellow-legged Gull Larus cachinnans has been based on differences or similarities in phenotype, morphology, and feeding and premating behavior. To shed some new light on the many taxonomic uncertainties surrounding these taxa, we describe the results of a large DNA study based on comparing the distribution of 209 biallelic markers among 109 gulls, representing 11 gull taxa of the Herring Gull assemblage and the Common Gull Larus canus. A detailed phylogenetic analysis failed to show clustering of individuals into groups representing either geographic origin or phenotype. Alternatively, birds were grouped into taxa defined on the basis of phenotype and geographic origin or phenotype alone. Genetic analyses revealed significantly different genetic distances between all pairs of taxa. However, based on these genetic distances, again no consistent phylogenetic tree could be constructed. Analysis of molecular variance indicated that about 77% of the total genetic variability among these gulls could be explained by within-taxon differences. Only 23% of the total genetic variability was due to genetic differences between taxa, irrespective of their species or subspecies status. Although this seems to challenge the current taxonomic treatment of the herring gull assemblage, our results are too premature and too incomplete to recommend a drastic change. PMID:11139298

  15. [Experimental infection caused by influenza A (H5N1) virus in common gull (Larus canus)].

    PubMed

    Za?kovskaia, A V; Sharshov, K A; Sherstkov, E A; Iurlov, A K; Shestopalov, A M

    2012-01-01

    The influenza A/common gull/Chany/P/2006 (HSN1) virus strain Isolated from a clinically healthy common gull (Larus canus) caused no death of Its natural host (a common gull). The virus was shown to be capable for effective replication in the tissues of the lung, spleen, and upper respiratory tract and in the intestinal mucosal cells of the common gull with further environmental virus liberation elimination along with mucinous discharges from the cloaca and fauces for 2 weeks. The potential role of this bird species in the circulation of influenza virus is discussed. PMID:23248859

  16. NATURAL SAND BYPASSING AND RESPONSE OF EBB SHOAL TO JETTY REHABILITATION, OCEAN CITY INLET, MARYLAND, USA

    E-print Network

    US Army Corps of Engineers

    1 NATURAL SAND BYPASSING AND RESPONSE OF EBB SHOAL TO JETTY REHABILITATION, OCEAN CITY INLET, the south jetty was raised and sand tightened, and surveys in 2004 and 2005 show seaward radial migration of the outer ridge of the ebb shoal in response to the jetty rehabilitation. Natural sand bypassing occurs

  17. Association patterns and foraging behaviour in natural and artificial guppy shoals

    Microsoft Academic Search

    Lesley J. Morrell; Darren P. Croft; John R. G. Dyer; Ben B. Chapman; Jennifer L. Kelley; Kevin N. Laland; Jens Krause

    2008-01-01

    Animal groups are often nonrandom assemblages of individuals that tend to be assorted by factors such as sex, body size, relatedness and familiarity. Laboratory studies using fish have shown that familiarity among shoal members confers a number of benefits to individuals, such as increased foraging success. However, it is unclear whether fish in natural shoals obtain these benefits through association

  18. APRIL 2008 Shroyer et. al. 1 Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves

    E-print Network

    APRIL 2008 Shroyer et. al. 1 Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves the shoaling of three groups of nonlinear internal waves of depression over 35 km across the shelf. Each wave The role of nonlinear internal waves (NLIWs) in the coastal ocean has been the study of recent

  19. Holocene sand shoals offshore of Mississippi River delta plain, Louisiana

    SciTech Connect

    Penland, S.; McBride, R.A. (Louisiana Geological Survey, Baton Rouge (USA)); Suter, J.R. (Exxon Production Research, Houston, TX (USA)); Williams, S.J. (Geological Survey, Reston, VA (USA)); Kindinger, J.L. (Geological Survey, St. Petersburg, FL (USA)); Boyd, R. (Dalhousie Univ., Halifax, Nova Scotia (Canada))

    1989-09-01

    Offshore of the Mississippi River delta plain lies a series of Holocene sand shoals marking the position of ancient submerged shorelines. These ancient shorelines represent stillstand positions during which the Holocene transgression drove sea level across the former lowstand subaerial erosion surface of the Mississippi River delta plain. Short periods of rapid sea level rise led to the transgressive submergence of these sandy shorelines. Two shoreline trends can be recognized at the {minus}10-m and {minus}20-m isobaths on the continental shelf.

  20. Social familiarity and shoal formation in juvenile fishes.

    PubMed

    Lee-Jenkins, S S Y; Godin, J-G J

    2010-02-01

    The potential influence of social familiarity in shoal-choice decisions was investigated in two sympatric species of north temperate fishes, juvenile banded killifish Fundulus diaphanus and juvenile bluegill sunfish Lepomis macrochirus. Groups of socially familiar and unfamiliar conspecifics were formed in the laboratory using wild-caught fishes. Juvenile F. diaphanus demonstrated a strong preference for familiar conspecific shoalmates, whereas juvenile L. macrochirus exhibited no preference for either unfamiliar or familiar conspecific shoalmates. The differential influence of familiarity on shoalmate choice in juveniles of these two species could be due to their different ecologies, local population densities and life histories. PMID:20666898

  1. Initial formation and evolution of channel-shoal patterns in estuaries , H.M. Schuttelaars1,2

    E-print Network

    Schuttelaars, Henk

    Initial formation and evolution of channel-shoal patterns in estuaries A. Hibma1* , H to simulate the formation of channels and shoals in a schematised estuary. The model set-up enables: estuaries, morphology, numerical model, shoals, channels, sand bars 1 INTRODUCTION Estuaries attract

  2. Immune function and organochlorine pollutants in Arctic breeding glaucous gulls.

    PubMed

    Bustnes, J O; Hanssen, S A; Folstad, I; Erikstad, K E; Hasselquist, D; Skaare, J U

    2004-11-01

    Organochlorine contaminants (OCs) are known to affect the immune systems of wildlife, and in this study we assessed the relationship between blood concentration of different OCs and measurements relevant to immune status and function in arctic breeding glaucous gulls (Larus hyperboreus). In 1997 and 2001, we counted white blood cells (heterophils and lymphocytes) from blood smears, and in 2000 and 2001 we injected two novel nonpathogenic antigens (diphtheria and tetanus toxoids) into the pectoral muscle of gulls and measured the primary antibody responses. We then related these measurements to the blood concentrations of three pesticides (hexachlorobenzene [HCB], oxychlordane, and p,p'-dichlorodiphenyldichloroethylene) and seven different polychlorinated biphenyl congeners (PCB 101, 99, 118, 153, 138, 180, and 170). There were significant or near significant positive relationships (0.1 > p > 0.001) between most persistent OCs and the levels of heterophils in the blood for both sexes in 1997 and for male gulls in 2001. Similarly, levels of all persistent OCs and lymphocytes were positively related (0.1 > p > 0.001) in both sexes in 1997. This suggests that OCs are causing alterations to immune systems, which may decrease their efficiency and make the birds more susceptible to parasites and diseases. In female gulls, the antibody response to the diphtheria toxoid was significant and negative for HCB (p < 0.01) and weaker, but significant, for oxychlordane (p < 0.05), suggesting that OCs were causing an impairment of the humoral immunity. Various OCs have been linked to negative effects in our study population, including decreased survival and reproduction, and this study suggests that such compounds also affect immune status and function. PMID:15499504

  3. Global warming and oil spills could cool shoaling reefs

    SciTech Connect

    Cubit, J.D. (Smithsonian Tropical Research Inst., Apdo (Panama))

    1990-01-09

    High water temperature generated on reef flats have been implicated as one of the factors determining the ecological patterns and structural morphologies peculiar to shoaling reefs. In approximately ten years of water temperature and water level data from a shoaling reef flat at Punta Galeta (Caribbean Panama), water temperatures were dependent on water levels. Water temperatures ranged up to 38[degrees]C when daily minimum water depths over the reef crest were < 12 cm, but never exceeded 30[degrees]C when the minimum water levels were > 12 cm. If conservative predictions of sea level rise caused by global warming are correct, normal vertical accretion rates of the reef flat could keep pace with rising sea level until the middle of the next century; after that the occurrence of high water temperatures would be rapidly reduced. However, damage from an oil spill at Punta Galeta in 1986 was concentrated at the seaward margin of the reef flat, where biogenic processes control the overall vertical accretion of the reef platform. By slowing rates of vertical accretion, oil impact could potentially accelerate the effects of global warming on the ecology and morphology of the reef.

  4. The influence of body coloration on shoaling preferences in fish.

    PubMed

    McROBERT; Bradner

    1998-09-01

    Shoaling behaviour provides antipredator benefits that rely, to some extent, on a high degree of phenotypic homogeneity between individuals within the shoal. Therefore, fish should have the ability to discriminate between potential shoalmates, choosing to associate with individuals of similar appearance to themselves. We studied the effects of a single phenotypic character, body coloration, on association choices made by black and white mollies (Poecilia latipinna). When given a choice between a group of mollies of similar coloration and an empty compartment, individual test fish (black or white) spent significantly more time near the fish group. When given a choice between a group of black mollies and a group of white mollies, individual fish (black or white) spent significantly more time near the group of mollies of similar coloration to their own. When given a choice between a group of mollies of dissimilar coloration and an empty compartment, black and white mollies reacted differently. Black mollies spent significantly more time on the side of the central compartment closest to the white mollies, while there was no significant difference between the time spent by white mollies on either side of the test tank. Our results indicate that fish can use visual cues to discriminate actively between potential shoalmates on the basis of body coloration. Copyright 1998 The Association for the Study of Animal Behaviour. PMID:9784209

  5. Exotic invaders gain foraging benefits by shoaling with native fish

    PubMed Central

    Camacho-Cervantes, Morelia; Garcia, Constantino Macías; Ojanguren, Alfredo F.; Magurran, Anne E.

    2014-01-01

    Freshwater habitats are under increasing threat due to invasions of exotic fish. These invasions typically begin with the introduction of small numbers of individuals unfamiliar with the new habitat. One way in which the invaders might overcome this disadvantage is by associating with native taxa occupying a similar ecological niche. Here we used guppies (Poecilia reticulata) from a feral population in Mexico to test the prediction that exotic shoaling fish can associate with heterospecifics, and that they improve their foraging efficiency by doing so. Guppies have invaded the Mexican High Plateau and are implicated in the declines of many native topminnow (Goodeinae) species. We show that heterospecific associations between guppies and topminnows can deliver the same foraging benefits as conspecific shoals, and that variation in foraging gains is linked to differences in association tendency. These results uncover a mechanism enabling founding individuals to survive during the most vulnerable phase of an invasion and help explain why guppies have established viable populations in many parts of Mexico as well in every continent except Antarctica.

  6. Newly discovered methoxylated polybrominated diphenoxybenzenes have been contaminants in the Great Lakes herring gull eggs for thirty years.

    PubMed

    Chen, Da; Letcher, Robert J; Gauthier, Lewis T; Chu, Shaogang; McCrindle, Robert

    2012-09-01

    We recently reported the discovery and identification of novel methoxylated polybrominated diphenoxybenzenes (MeO-PBDPBs) in herring gulls eggs from the Laurentian Great Lakes of North America. We presently investigated the temporal changes (1982-2010) in MeO-PBDPB concentrations and congener patterns, as well as chemical tracers of diet (ratios of carbon and nitrogen stable isotopes), in egg pool homogenates from five selected colony sites across the Great Lakes. Egg pool homogenates from the Channel-Shelter (C-S) Island (Lake Huron) contained ?MeO-PBDPB concentrations orders of magnitude greater than those from other colonies, suggesting potential point contamination sources nearby. In the C-S Island egg pools, concentrations increased from the initial study year (31 ng/g wet weight) and peaked around the late 1990s, followed by a general decline until 2010. Over the period, concentrations generally increased in eggs from Fighting Island (Lake Erie), Toronto Harbour (Lake Ontario) and Big Sister Island (Lake Michigan) colonies, whereas the levels in Agawa Rock (Lake Superior) declined. Although other factors likely exist, changes over time in the carbon and nitrogen isotope tracers reflected a shift of the gull diet from aquatic to more terrestrial origins, and suggested this diet shift partially accounted for the temporal changes of ?MeO-PBDPB levels in eggs from most colonies. The ratio of Br(6)- to Br(5)-MeO-PBDPB congeners generally decreased over time in the colonies at Channel-Shelter Island, Fighting Island and Agawa Rock. This suggested that Br(5)- versus Br(6)-MeO-PBDPB congeners and/or possibly their nonmethoxylated and higher brominated precursors may have been more abundant in diets of terrestrial origin. Notably, these MeO-PBDPB congeners are not "emerging" brominated substances, but rather "recently discovered" contaminants since, as of 2011, ?MeO-PBDPB concentrations have been constantly in the range of 30-100 ng/g ww for at least the last 30 years. PMID:22889009

  7. Polychlorinated biphenyls in diseased lesser black-backed gull ( Larus fuscus fuscus) chicks from the Gulf of Finland

    Microsoft Academic Search

    M Hario; K Himberg; T Hollmén; E Rudbäck

    2000-01-01

    Diseases due to the degeneration of the liver and various other internal organs were the major cause of the exceedingly high chick mortality in lesser black-backed gulls (Larus fuscus fuscus) in the central Gulf of Finland, Baltic Sea, during 1991–1993. The same symptoms were found in chicks of common gulls (Larus canus) and herring gulls (Larus argentatus) from the same

  8. Isolation of Salmonella spp. from dead gulls (Larus californicus and Larus delawarensis) from an Idaho irrigation reservoir.

    PubMed

    Hall, R F; Waldhalm, D G; Meinershagen, W A; DuBose, D A

    1977-01-01

    An epizootic of unknown etiology resulting in the death of about 500 sea gulls (Larus californicus and Larus delawarensis) in 24 hr occurred on an irrigation reservoir in southwestern Idaho in April 1975. Salmonella spp. were isolated from necropsy specimens from 2 of 6 gulls examined. No Salmonella spp. were isolated from fecal specimens or dead gulls collected at a nesting site. PMID:334150

  9. Anatomy and Histochemistry of Spread-Wing Posture in Birds. 2. Gliding Flight in the California Gull, Larus californicus

    E-print Network

    Meyers, Ron

    Gull, Larus californicus: A Paradox of Fast Fibers and Posture RON A. MEYERS* AND EDWARD MATHIAS in gliding posture were examined in California gulls (Larus californicus) and tested for the presence of slow in herring gulls (Larus argentatus) (Gold- spink et al., '78) andAmerican kestrels (Falco sparverius) (Meyers

  10. VOL. 65, NO. 3 (SEPTEMBER 2012) P. 283288 Breeding Habitats and New Breeding Locations for Ross's Gull (Rhodostethia rosea)

    E-print Network

    Jones, Ian L.

    for Ross's Gull (Rhodostethia rosea) in the Canadian High Arctic MARK MAFTEI,1,2 SHANTI E. DAVIS,1 IAN L) ABSTRACT. Published accounts list only four breeding sites for Ross's gull (Rhodostethia rosea) in North poorly known species in North America. Key words: Ross's gull, Rhodostethia rosea, breeding site, High

  11. Hybridization of glaucous gull (Larus hyperboreus) and herring gull (Larus argentatus) in Iceland: mitochondrial and microsatellite data.

    PubMed

    Vigfúsdóttir, Freydís; Pálsson, Snaebjörn; Ingólfsson, Agnar

    2008-09-12

    Large white-headed gulls provide an interesting group of birds for studies of hybridization. The group is composed of 20 species of recent origin, often with weak reproductive barriers. Here we report the results from a study on the glaucous gull Larus hyperboreus, an Arctic species which has been breeding in Iceland for centuries, and the herring gull Larus argentatus which has a wide distribution in Europe but colonized Iceland in 1920s. Previous studies, based on morphological variation indicated hybridization between the two species in Iceland, have been questioned as it may just reflect variation within the species. Here we evaluate whether hybridization has occurred between the two species in Iceland by studying variation in microsatellites and mtDNA. The analysis is based on feathers taken from wings sampled in Iceland over a period of 40 years. The results are compared with samples obtained from East Greenland and published sequences of samples obtained throughout Europe. The genetic analysis reveals a distinctive grouping of the two species, although they present a shallow genealogy and an extensive sharing of the genetic variants between the two species. Several individuals show admixture for molecular markers, which may result from an incomplete lineage sorting although geographical patterns of both mtDNA haplotypes and microsatellites strongly indicate a recent hybridization in Iceland. PMID:18508755

  12. USE OF TIPS BY NESTING KELP GULLS AT A GROWING COLONY IN PATAGONIA

    Microsoft Academic Search

    MARCELO BERTELLOTTI; PABLO YORIO; MARICEL GIACCARDI

    We evaluated the magnitude of use of waste tips by Kelp Gulls (Larus domini- canus) nesting at Isla de los Pajaros, a large and growing colony in Patagonia, Argentina, and we assessed the difference in use between tips with urban and fishery waste. We marked with color dye 1347 adult breeding Kelp Gulls to determine if they fed in urban

  13. Molecular Detection of Campylobacter spp. in California Gull (Larus californicus) Excreta

    EPA Science Inventory

    We examined the prevalence, quantity, and diversity of Campylobacter species in the excreta of 159 California gull samples using PCR and qPCR based detection assays. While Campylobacter prevalence and abundance was relatively high in the gull excreta examined, molecular data ind...

  14. Validation of Water Flux and Body Composition in Glaucous Gulls ( Larus hyperboreus )

    Microsoft Academic Search

    Scott A. Shaffer; Geir W. Gabrielsen; Jonathan Verreault; Daniel P. Costa

    2006-01-01

    Water influx rates (WIR) measured with tritiated water dilution were compared with direct measures of water and energy intake in glaucous gulls (Larus hyperboreus). Total body water (TBW) measured isotopically was also compared with TBW deter- mined by body composition analysis (BCA) of the same birds. Seventeen wild gulls were captured and studied in outdoor

  15. Simulating the Effects of Predation and Egg-harvest at a Gull Colony

    Microsoft Academic Search

    Stephani Zador; John F. Piatt

    We developed an individual-based simulation model to explore the effects of harvesting eggs from a glaucous-winged gull (Larus glaucescens) colony that also experiences egg loss from avian predators. The model has direct application to Glacier Bay National Park, where resource managers are interested in the potential effects of traditional harvesting of gull eggs at colonies within the park. This model

  16. GENETIC DIFFERENTIATION, GEOGRAPHIC VARIATION AND HYBRIDIZATION IN GULLS OF THE LARUS GLA UCESCENS-OCCIDENTALIS COMPLEX

    Microsoft Academic Search

    DOUGLAS A. BELLY

    Survey of morphometric, calorimetric, and allozymic variation in the Glau- cous-winged Gull (Larus glaucescens), the Western Gull (L. occidentalis) and their hybrids is based on 706 specimens taken from 33 colony areas located throughout the breeding range of both species. Whereas most morphometric characters overlap between taxa, col- orimetric characters exhibited significant intraspecific and interspecific clinal variation. Ca- nonical discriminant

  17. CLAM DROPPING BEHAVIOR OF THE GLAUCOUS-WINGED GULL (LARUS GLAUCESCENS)

    Microsoft Academic Search

    DAVID P. BARASH; PATRICK DONOVAN; RINDA MYRICK

    Tinbergen (1961) and Oldham (1930) h ave reported that Herring Gulls (Larus argentatus) commonly drop whelks (Baccinum undatum) and other hard-shelled molluscs in order to break them open, but that their selection of substrate appears to be random, with the birds as likely to drop potential food objects on soft surfaces (sand) as on hard (rocks). The European Gull (Lurus

  18. Relationship between Egg Size and Post-hatching Chick Mortality in the Herring Gull (Larus argentatus)

    Microsoft Academic Search

    J. Parsons

    1970-01-01

    IN many gull species, the third laid egg of the typical three egg clutch is distinctly smaller than the first two1,2. In the herring gull (Larus argentatus), the chick hatching from this third egg suffers a much higher mortality than either of its siblings3, although the hatching success is the same for all three eggs. In a series of egg

  19. Bacteroidales diversity in ring-billed gulls (Laurus delawarensis) residing at Lake Michigan beaches.

    PubMed

    Jeter, Sonja N; McDermott, Colleen M; Bower, Patricia A; Kinzelman, Julie L; Bootsma, Melinda J; Goetz, Giles W; McLellan, Sandra L

    2009-03-01

    This study investigated the occurrence and diversity of Bacteroidales fecal bacteria in gulls residing in the Great Lakes region. Members of this bacterial order have been widely employed as human and bovine host-specific markers of fecal pollution; however, few studies have focused on gulls, which can be a major source of fecal indicator bacteria and pathogens at beaches. We found a low but consistent occurrence of Bacteroidales in gulls at five beaches in three different counties spanning the Wisconsin shoreline of Lake Michigan. The percentages of gulls positive for Bacteroidales were 4 to 8% at beaches in the southern part of the state and 8 to 50% at beaches in the north. Sequencing of 931 clones from seven gull Bacteroidales 16S rRNA gene libraries revealed a large amount of diversity in both individual and pooled gull fecal samples. Two libraries constructed from pooled gull fecal samples (n = 5 and n = 6) did not have a greater richness of sequences than individual samples, suggesting that even within a single gull diversity is high and an extensive sequencing effort is needed to characterize the populations. Estimates of the numbers of operational taxonomic units (OTUs) for the libraries obtained using different similarity levels revealed a large amount of microdiveristy with a limited number of OTUs at the 95% similarity level. Gull sequences were clustered by the beach from which they were collected, suggesting that there were geographic effects on the distribution of Bacteriodales. More than 53% of the 16S rRNA gene sequences from gulls at the southern beaches were associated with the family Porphyromonadaceae, primarily the genus Parabacteroides, whereas sequences from gulls at the northern beaches were comprised of Bacteroidaceae and Prevotellaceae sequences. Comparison of gull sequences with sequences from goose, canine, raccoon, and sewage sources revealed distinct clusters of closely related gull sequences; however, these sequences were widely dispersed across a dendrogram that included all other sources, including previously characterized gull Bacteroidales from other studies, suggesting that geographic influence or simply sample representation plays a greater role in the observed population structure than strictly the host gut environment. PMID:19151182

  20. Bacteroidales Diversity in Ring-Billed Gulls (Laurus delawarensis) Residing at Lake Michigan Beaches?

    PubMed Central

    Jeter, Sonja N.; McDermott, Colleen M.; Bower, Patricia A.; Kinzelman, Julie L.; Bootsma, Melinda J.; Goetz, Giles W.; McLellan, Sandra L.

    2009-01-01

    This study investigated the occurrence and diversity of Bacteroidales fecal bacteria in gulls residing in the Great Lakes region. Members of this bacterial order have been widely employed as human and bovine host-specific markers of fecal pollution; however, few studies have focused on gulls, which can be a major source of fecal indicator bacteria and pathogens at beaches. We found a low but consistent occurrence of Bacteroidales in gulls at five beaches in three different counties spanning the Wisconsin shoreline of Lake Michigan. The percentages of gulls positive for Bacteroidales were 4 to 8% at beaches in the southern part of the state and 8 to 50% at beaches in the north. Sequencing of 931 clones from seven gull Bacteroidales 16S rRNA gene libraries revealed a large amount of diversity in both individual and pooled gull fecal samples. Two libraries constructed from pooled gull fecal samples (n = 5 and n = 6) did not have a greater richness of sequences than individual samples, suggesting that even within a single gull diversity is high and an extensive sequencing effort is needed to characterize the populations. Estimates of the numbers of operational taxonomic units (OTUs) for the libraries obtained using different similarity levels revealed a large amount of microdiveristy with a limited number of OTUs at the 95% similarity level. Gull sequences were clustered by the beach from which they were collected, suggesting that there were geographic effects on the distribution of Bacteriodales. More than 53% of the 16S rRNA gene sequences from gulls at the southern beaches were associated with the family Porphyromonadaceae, primarily the genus Parabacteroides, whereas sequences from gulls at the northern beaches were comprised of Bacteroidaceae and Prevotellaceae sequences. Comparison of gull sequences with sequences from goose, canine, raccoon, and sewage sources revealed distinct clusters of closely related gull sequences; however, these sequences were widely dispersed across a dendrogram that included all other sources, including previously characterized gull Bacteroidales from other studies, suggesting that geographic influence or simply sample representation plays a greater role in the observed population structure than strictly the host gut environment. PMID:19151182

  1. Sex biases in kin shoaling and dispersal in a cichlid fish.

    PubMed

    van Dongen, Wouter F D; Wagner, Richard H; Moodley, Yoshan; Schaedelin, Franziska C

    2014-12-01

    Animal dispersal is associated with diverse costs and benefits that vary among individuals based on phenotype and ecological conditions. For example, females may disperse when males benefit more from defending territories in familiar environments. Similarly, size differences in dispersal propensity may occur when dispersal costs are size-dependent. When individuals do disperse, they may adopt behavioral strategies that minimize dispersal costs. Dispersing fish, for example, may travel within shoals to reduce predation risks. Further, kin shoaling may augment inclusive fitness by reducing predation of relatives. However, studies are lacking on the role of kin shoaling in dispersal. We explored how sex and size influence dispersal and kin shoaling in the cichlid Neolamprologus caudopunctatus. We microsatellite genotyped over 900 individuals from two populations separated by a potential dispersal barrier, and documented patterns of population structure, migration and within-shoal relatedness. Genetic differentiation across the barrier was greater for smaller than larger fish, suggesting larger fish had dispersed longer distances. Females exhibited weaker genetic differentiation and 11 times higher migration rates than males, indicating longer-distance female-biased dispersal. Small females frequently shoaled with siblings, possibly offsetting dispersal costs associated with higher predation risks. In contrast, small males appeared to avoid kin shoaling, possibly to avoid local resource competition. In summary, long-distance dispersal in N. caudopunctatus appears to be female-biased, and kin-based shoaling by small females may represent a behavioral adaptation that reduces dispersal costs. Our study appears to be the first to provide evidence that sex differences in dispersal influence sex differences in kin shoaling. PMID:25231372

  2. Comparison of Trace Element Concentrations Between Chick and Adult Black-Tailed Gulls (Larus crassirostris).

    PubMed

    Kim, Jungsoo; Oh, Jong-Min

    2015-06-01

    Trace elements were measured in the feathers of black-tailed gull chicks (n = 10) and adults (n = 10) collected at Chilsando Is., Jeollanam-do, Korea, in June 2011. Pb, Mn and Fe were significantly greater in adult (arithmetic mean 2.02, 3.81, 92.1 ?g/g dw, respectively) than chick (0.74, 2.14, 68.7 ?g/g dw) gulls. In contrast, Zn was greater in chicks (74.9 ?g/g dw) than adults (46.5 ?g/g dw). Cd, Pb and Cr in all chicks and adults were lower than an approximate threshold level for toxic effects. Cd, Pb and Cr were comparable or lower than reported in other gull studies worldwide. Essential elements including Al, Cu, Mn, Zn and Fe were within the background and normal physiological levels reported earlier in other gull species including black-tailed gulls. PMID:25899571

  3. Modelling terrestrial and marine foraging habitats in breeding Audouin's gulls Larus audouinii: timing matters.

    PubMed

    Bécares, Juan; García-Tarrasón, Manuel; Villero, Dani; Bateman, Santiago; Jover, Lluís; García-Matarranz, Víctor; Sanpera, Carolina; Arcos, José Manuel

    2015-01-01

    Although the breeding ecology of Audouin's gull has been widely studied, its spatial distribution patterns have received little attention. We assessed the foraging movements of 36 GPS-tracked adult Audouin's gulls breeding at the Ebro Delta (NW Mediterranean), coinciding with the incubation period (May 2011). This also coincided with a trawling moratorium northwards from the colony. We modelled the distribution of the gulls by combining these tracking data with environmental variables (including fishing activities from Vessel Monitoring System, VMS), using Maxent. The modelling range included both marine and terrestrial areas. Models were produced separately for every 2h time interval across the day, and for 2 fishing activity scenarios (workdays vs. weekends), allowing to assess the spatio-temporal distribution patterns of the gulls and the degree of association with fisheries. During workdays, gull distribution at sea fully matched with fishing activities, both trawling (daylight) and purse-seining (nightime). Gulls tended to avoid the area under trawling moratorium, confirming the high influence of fisheries on the distribution patterns of this species. On weekends, gulls made lesser use of the sea and tended to increase the use of rice fields. Overall, Audouin's gull activity was more intense during dailight hours, although birds also showed nocturnal activity, on both workdays and weekends. Nocturnal patterns at sea were more disperse during the latter, probably because these gulls are able to capture small pelagic fish at night in natural conditions, but tend to congregate around purse-seiners (which would enhance their foraging efficiency) in workdays. These results provide important insight for the management of this species. This is of particular relevance under the current scenario of European fisheries policies, since new regulations are aimed at eliminating discards, and this would likely influence Audouin's gull populations. PMID:25875597

  4. FLUORIDE EXPOSURE AND SELECTED CHARACTERISTICS OF EGGS AND BONES OF THE HERRING GULL (LARUS ARGENTATUS) AND THE COMMON GULL (LARUS CANUS)

    Microsoft Academic Search

    Turid Vikoren; Gudbrand Stuve

    Fluorine concentrations were determined in the shellof 285 herring gull eggs (Laru.s' argentatus) and 120 comnmon gull eggs (Larus canus), collectedMay 1991 to 1993, from breeding colonies eXpd)se(l to emissions from two Norwegian primary aluminum smiielters locatedatKarni#{248}y and Sunndai, amid from unexposed reference localities in Eigersund, Sola, and Stavanger. Volume- index,shellthickness,thickness-index,and fertilization of the eggs also were monitore(l. In 1)0th

  5. Closure report for CAU No. 416: Project Shoal Area

    SciTech Connect

    NONE

    1998-01-01

    This Closure Report provides the documentation for closure of the US Department of Energy/Nevada Operations Office (DOE/NV) Project Shoal Area (PSA) Surface Corrective Action Unit (CAU) 416. CAU 416 consists of a mud pit, muckpile, and housekeeping site. The PSA is located approximately 48.3 kilometers (30 miles) southeast of Fallon, Nevada. The mud pit was the result of drilling activities at the PSA in 1963. Investigation activities completed in 1996 determined drilling mud in the mud pit was impacted with petroleum hydrocarbons in excess of the State of Nevada 100 milligram per kilogram (mg/kg). The muckpile consists of broken granite from emplacement shaft and drift (tunnel) mining activities at the PSA in 1963. The housekeeping site consisted of approximately 20 used, empty, rusted, steel 0.9 liter (1 quart) oil cans.

  6. Wetland birds of Hainan Island, China: results from winter waterbird surveys 2003-2007

    Microsoft Academic Search

    LEE KWOK SHING; BOSCO PUI LOK

    2007-01-01

    Four simultaneous winter waterbird surveys were conducted island-wide on Hainan island, China, between 2003 and 2007, during which a total of 83 species of wetland-associated birds were recorded at 57 coastal and freshwater wetlands. The most abundant species were egrets and herons, followed by shorebirds, gulls and terns, and ducks. A new wintering site for the globally Endangered Black-faced Spoonbill

  7. The distribution and conservation status of the Gull-billed Tern (Gelochelidon nilotica) in North America

    USGS Publications Warehouse

    Molina, K.C.; Erwin, R.M.

    2006-01-01

    The Gull-billed Tern (Gelochelidon nilotica) has until recently received little conservation and management attention within North America despite a relatively low overall population size and significant declines in parts of the breeding range. This lack of attention may stem in part from the wide distribution of the species, encompassing parts of six continents, and from its tendency to nest in relatively small, scattered and often ephemeral colonies. Populations of North American subspecies are alarmingly small. The current population of the eastern subspecies aranea in the U.S. is unlikely to exceed 3,600 pairs, with over 60% of these birds occurring in Texas. The Texas population has remained generally stable, but declines of populations in Maryland (where probably extirpated), Virginia, North Carolina, Florida, and possibly Georgia give cause for concern for this subspecies. For the western subspecies vanrossemi, as few as 250 pairs nest at only two locations in the U.S., both in California. When populations in western Mexico are considered, the entire vanrossemi population numbers only 600-800 pairs. Currently the Gull-billed Tern is listed as ?endangered? or ?threatened? in four states, and is considered to be of management concern in five others. The breeding range of the species has contracted and shifted slightly from its known historic range in the middle Atlantic states, but otherwise occupies its historic range in the United States and has expanded slightly to coastal southern California. Some range contraction in Mexico (e.g., in Sonora) may have occurred. In eastern Mexico, historical information is almost non-existent and knowledge of current distribution and abundance is incomplete. Main threats to populations in North America include loss of natural nesting islands through beach erosion or perturbations to estuarine functions, development or modification of upland habitats near breeding areas that may be important for foraging, and disturbances to colonies by humans and feral or human-subsidized predators. This species often nests on man-made substrates suggesting it could be responsive to management of breeding sites. Key research needs include more frequent and refined population monitoring, a better understanding of demographics, metapopulation dynamics and factors limiting populations as well as refinement of subspecies? breeding distributions and wintering ranges.

  8. Herring gull eggs indicate stabilizing Great Lakes PCB concentrations

    SciTech Connect

    Stow, C. [Univ. of Wisconsin, Madison, WI (United States). Center for Limnology

    1995-12-31

    The author evaluated the fit of 3 alternative models to herring gull (Larus argentatus) egg PCB concentration data from 1978--1992 to examine whether PCB levels were decreasing or had ceased to decline. The best fit models indicate that, following initial declines, no discernible PCB decreases are occurring in 4 of the 5 lakes. Only Lake Erie indicates a continued PCB decline, though the Erie data may be too noisy to differentiate model fits. These results are consistent with previous analyses indicating stable PCB concentrations in Lake Michigan fishes and suggest that further improvements may be too slow to be of practical importance from a management perspective.

  9. Size-assortative shoaling in fish: the effect of oddity on foraging behaviour

    Microsoft Academic Search

    NINA PEUHKURI

    1997-01-01

    Current theory predicts that fish should show size-assortative shoaling in order to avoid increased predation risk by being the odd one out (oddity effect), or in order to minimize competition for food. I investigated with three-spined sticklebacks,Gasterosteus aculeatusthe importance of the oddity effect in promoting size-assortative shoaling. The greater an individual assesses its predation risk the less actively it is

  10. Fish cam: an online tool for introducing shoaling behavior to the classroom.

    PubMed

    Southwell, Maura; Galassi, Maria; McRobert, Scott

    2012-12-01

    Fish Cam is an on-line educational resource that enables students to participate in behavioral research projects without ever leaving their classroom. By linking onto the Fish Cam site, students will observe an experimental tank in which fish choose shoal-mates in dichotomous choice tests. In these experiments, a test fish, in the central compartment, displays its shoaling preference by swimming near small shoals of fish in either of two side compartments. Assays are designed to examine the effects of phenotype, shoal size, and other factors known to influence shoaling. Students monitor Fish Cam in real time, and students collect data simply by running timers when the test fish crosses into the preference zones at each end of the central compartment. The times are logged onto data sheets that we provide, and we assist the students with their analysis. The simplicity of shoaling behavior makes it an ideal model system for data collection that is accessible to students of all ages and, in its first few years of operation, Fish Cam studies have been performed by fifth-, seventh- and eleventh-grade students. Sample lesson plans and handouts are available online to enhance the Fish Cam experience. The ultimate goals of this project are to make scientific research accessible in the classroom and promote science education. PMID:23244694

  11. Microsatellites identify depredated waterfowl remains from glaucous gull stomachs

    USGS Publications Warehouse

    Scribner, K.T.; Bowman, T.D.

    1998-01-01

    Prey remains can provide valuable sources of information regarding causes of predation and the species composition of a predator's diet. Unfortunately, the highly degraded state of many prey samples from gastrointestinal tracts often precludes unambiguous identification. We describe a procedure by which PCR amplification of taxonomically informative microsatellite loci were used to identify species of waterfowl predated by glaucous gulls (Larus hyperboreus). We found that one microsatellite locus unambiguously distinguished between species of the subfamily Anserinae (whistling ducks, geese and swans) and those of the subfamily Anatidae (all other ducks). An additional locus distinguished the remains of all geese and swan species known to nest on the Yukon-Kuskokwim delta in western Alaska. The study focused on two waterfowl species which have experienced precipitous declines in population numbers: emperor geese (Chen canagica) and spectacled eiders (Somateria fischeri). No evidence of predation on spectacled eiders was observed. Twenty-six percent of all glaucous gull stomachs examined contained the remains of juvenile emperor geese.

  12. Validation Analysis of the Shoal Groundwater Flow and Transport Model

    SciTech Connect

    A. Hassan; J. Chapman

    2008-11-01

    Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical models of groundwater flow and radionuclide transport. Agreement on a contaminant boundary for the site and a corrective action plan was reached in 2006. Later that same year, three wells were installed for the purposes of model validation and site monitoring. The FFACO prescribes a five-year proof-of-concept period for demonstrating that the site groundwater model is capable of producing meaningful results with an acceptable level of uncertainty. The corrective action plan specifies a rigorous seven step validation process. The accepted groundwater model is evaluated using that process in light of the newly acquired data. The conceptual model of ground water flow for the Project Shoal Area considers groundwater flow through the fractured granite aquifer comprising the Sand Springs Range. Water enters the system by the infiltration of precipitation directly on the surface of the mountain range. Groundwater leaves the granite aquifer by flowing into alluvial deposits in the adjacent basins of Fourmile Flat and Fairview Valley. A groundwater divide is interpreted as coinciding with the western portion of the Sand Springs Range, west of the underground nuclear test, preventing flow from the test into Fourmile Flat. A very low conductivity shear zone east of the nuclear test roughly parallels the divide. The presence of these lateral boundaries, coupled with a regional discharge area to the northeast, is interpreted in the model as causing groundwater from the site to flow in a northeastward direction into Fairview Valley. Steady-state flow conditions are assumed given the absence of groundwater withdrawal activities in the area. The conceptual and numerical models were developed based upon regional hydrogeologic investigations conducted in the 1960s, site characterization investigations (including ten wells and various geophysical and geologic studies) at Shoal itself prior to and immediately after the test, and two site characterization campaigns in the 1990s for environmental restoration purposes (including eight wells and a year-long tracer test). The new wells are denoted MV-1, MV-2, and MV-3, and are located to the northnortheast of the nuclear test. The groundwater model was generally lacking data in the north-northeastern area; only HC-1 and the abandoned PM-2 wells existed in this area. The wells provide data on fracture orientation and frequency, water levels, hydraulic conductivity, and water chemistry for comparison with the groundwater model. A total of 12 real-number validation targets were available for the validation analysis, including five values of hydraulic head, three hydraulic conductivity measurements, three hydraulic gradient values, and one angle value for the lateral gradient in radians. In addition, the fracture dip and orientation data provide comparisons to the distributions used in the model and radiochemistry is available for comparison to model output. Goodness-of-fit analysis indicates that some of the model realizations correspond well with the newly acquired conductivity, head, and gradient data, while others do not. Other tests indicated that additional model realizations may be needed to test if the model input distributions need refinement to improve model performance. This approach (generating additional realizations) was not followed because it was realized that there was a temporal component to the data disconnect: the new head measurements are on the high side of the model distributions, but the heads at the original calibration locations themselves have also increased over time. This indicates that the steady-state assumption of the groundwater model is in error. To test the robustness of the model d

  13. The geomorphology of the Chandeleur Island Wetlands

    SciTech Connect

    Debusschere, K.; Penland, S.; Westphal, K. (Louisiana Geological Survey, Baton Rouge (USA)); Handley, L. (Fish and Wildlife Service, Slidell, LA (USA)); Michot, T. (Fish and Wildlife Service, Baton Rouge, LA (USA)); Reed, D.; Seal, R.

    1990-09-01

    The Chandeleur Islands represent the largest and oldest transgressive barrier island arc in the northern Gulf of Mexico. Generated by the transgressive submergence of the St. Bernard delta complex, the Chandeleur Islands form the protective geologic framework for one of the richest areas of salt marsh and seagrass flats in Louisiana. The Chandeleur barrier island arc is 60 km long and consists of five individual islands backed by a linear, multiple bar system enclosing a shallow basin floored by extensive seagrass flats. The northern part of the Chandeleur chain is the highest in relief, elevation, width, and habitat diversity. Nonstorm morphology is predominantly a combination of continuous dunes and dune terraces. Numerous washover channels and large washover fans extend into the backbarrier environment. Further south, the island width decreases and washover flats and terraces dominate the shoreline morphology In the southernmost section, the island arc is fragmented into a series of small islands and shoals separated by tidal inlets. Between 1984 and 1989, aerial videotape, aerial photographic, and bathymetric surveys were used to map and monitor the geomorphic changes occurring along the shoreline and in backbarrier areas. The aerial videotape mapping surveys focused on the impacts of hurricanes Danny, Elena, and Juan on the geomorphology of the islands. Videotape imagery was acquired in July 1984 and in July (prestorm), August (post-Danny), September (post-Elena), and November (post-Juan) 1985. A coastal geomorphic classification was developed to map the spatial and temporal landscape changes between surveys.

  14. Mercury concentration in 3 species of Gulls, Larus ridibundus, Larus minutus, Larus canus, from south coast of the Caspian Sea, Iran.

    PubMed

    Rajaei, Fateme; Esmaili Sari, Abbas; Bahramifar, Nader; Ghasempouri, Seyed Mahmoud; Savabieasfahani, Mozhgan

    2010-06-01

    In this study, the mercury concentrations of liver, breast feathers and tail feathers in three species of Gull; Black-headed Gull (Larus ridibundus), Common Gull (Larus canus) and Little Gull (Larus minutus) from the South coast of the Caspian Sea in Iran were assayed. Mercury accumulation in liver, breast feathers and tail feathers of species were 1.69-3.16, 2.88-7.18 and 2.09-5.66 mg/kg, respectively. Mercury concentration hierarchy in tissues we tested was as follows: breast feather > tail feather > and liver. We found that despite its small size, Little Gull had highest (3.85-8.05 mg/kg) and Common Gull lowest (1.69-2.88 mg/kg) level of Hg in their bodies. An inverse relationship between body size and Hg levels in these Gulls was detected. Mercury in Little Gull and Black-headed Gull exceeded the 5 ppm threshold for adverse effect. PMID:20424818

  15. Inferring the rules of interaction of shoaling fish.

    PubMed

    Herbert-Read, James E; Perna, Andrea; Mann, Richard P; Schaerf, Timothy M; Sumpter, David J T; Ward, Ashley J W

    2011-11-15

    Collective motion, where large numbers of individuals move synchronously together, is achieved when individuals adopt interaction rules that determine how they respond to their neighbors' movements and positions. These rules determine how group-living animals move, make decisions, and transmit information between individuals. Nonetheless, few studies have explicitly determined these interaction rules in moving groups, and very little is known about the interaction rules of fish. Here, we identify three key rules for the social interactions of mosquitofish (Gambusia holbrooki): (i) Attraction forces are important in maintaining group cohesion, while we find only weak evidence that fish align with their neighbor's orientation; (ii) repulsion is mediated principally by changes in speed; (iii) although the positions and directions of all shoal members are highly correlated, individuals only respond to their single nearest neighbor. The last two of these rules are different from the classical models of collective animal motion, raising new questions about how fish and other animals self-organize on the move. PMID:22065759

  16. Fluid management plan for the Project Shoal Area Offsites Subproject

    SciTech Connect

    NONE

    1996-08-01

    The US Department of Energy, Nevada Operations Office (DOE/NV) has initiated the Offsites Subproject to characterize the hazards posed to human health and the environment as a result of underground nuclear testing activities at facilities other than the Nevada Test Site (NTS). A primary Subproject objective is to gather adequate data to characterize the various Subproject sites through the collection of surface and subsurface soil samples and by drilling several wells for the collection of groundwater data. The Project Shoal Area (PSA) is one of the Subproject`s Nevada sites and is subject to the requirements set forth in the Federal Facility Compliance Agreement and Consent Order (FFACO) (DOE, 1996a). In accordance with the FFACO, a Corrective Action Investigation Plan (CAIP) has been developed for work at the PSA (designated as Corrective Action Unit Number 416). This Fluid Management Plan (FMP) provides guidance for the management of fluids generated from wells constructed at the PSA. Long-term monitoring and future activities at the site, if required, will be set forth in additional documents as required by the FFACO. The ultimate method for disposition of fluids generated by site operations depends upon sample analysis and process knowledge in relation to fluid management criteria. Section 2 describes well site operations; Section 3 discusses fluid management criteria; Section 4 includes the fluid monitoring program; Section 5 presents the fluid management strategy; Section 6 provides for fluid management during routine well monitoring; and Section 7 contains reporting criteria.

  17. Tidally-forced flow in a rotating, stratified, shoaling basin

    NASA Astrophysics Data System (ADS)

    Winters, Kraig B.

    2015-06-01

    Baroclinic flow of a rotating, stratified fluid in a parabolic basin is computed in response to barotropic tidal forcing using the nonlinear, non-hydrostatic, Boussinesq equations of motion. The tidal forcing is derived from an imposed, boundary-enhanced free-surface deflection that advances cyclonically around a central amphidrome. The tidal forcing perturbs a shallow pycnocline, sloshing it up and down over the shoaling bottom. Nonlinearities in the near-shore internal tide produce an azimuthally independent 'set-up' of the isopycnals that in turn drives an approximately geostrophically balanced, cyclonic, near-shore, sub-surface jet. The sub-surface cyclonic jet is an example of a slowly evolving, nearly balanced flow that is excited and maintained solely by forcing in the fast, super-inertial frequency band. Baroclinic instability of the nearly balanced jet and subsequent interactions between eddies produce a weak transfer of energy back into the inertia-gravity band as swirling motions with super-inertial vorticity stir the stratified fluid and spontaneously emit waves. The sub-surface cyclonic jet is similar in many ways to the poleward flows observed along eastern ocean boundaries, particularly the California Undercurrent. It is conjectured that such currents may be driven by the surface tide rather than by winds and/or along-shore pressure gradients.

  18. Organohalogen contamination in breeding glaucous gulls from the Norwegian Arctic: Associations with basal metabolism and

    E-print Network

    Bech, Claus

    )- and methoxylated (MeO)-PBDEs and OH-PCBs, circulating TH levels and BMR in breeding glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Negative associations were found between BMR and concentrations of P

  19. Infectious bursal disease virus antibodies in eider ducks and Herring Gulls

    USGS Publications Warehouse

    Hollmen, T.; Franson, J.C.; Docherty, D.E.; Kilpi, Mikael; Hario, Martti; Creekmore, L.H.; Petersen, M.R.

    2000-01-01

    We measured antibodies to infectious bursal disease virus (IBDV) in blood of nesting Common Eider (Somateria mollissima) females and immature Herring Gulls (Larus argentatus) in the Baltic Sea, and in blood of Spectacled Eider (Somateria fischeri) females nesting in a remote area of western Alaska. Positive (??? 1:16) IBDV titers occurred in 75% of the eiders and 45% of the Herring Gull chicks. In eiders, the prevalence of positive titers differed among locations. We found no evidence that IBDV exposure impaired the immune function of Herring Gull chicks, based on their response to inoculation of sheep red blood cells. We suggest that eider ducks and Herring Gulls have been exposed to IBDV, even in locations where contact with poultry is unlikely. The presence of this virus in wild bird populations is of concern because it causes mortality of up to 30% in susceptible poultry.

  20. Perfluoroalkyl carboxylates and sulfonates and precursors in relation to dietary source tracers in the eggs of four species of gulls (Larids) from breeding sites spanning Atlantic to Pacific Canada.

    PubMed

    Gebbink, Wouter A; Letcher, Robert J; Burgess, Neil M; Champoux, Louise; Elliott, John E; Hebert, Craig E; Martin, Pamela; Wayland, Mark; Weseloh, D V Chip; Wilson, Laurie

    2011-10-01

    In the present study, we identified and examined the spatial trends, sources and dietary relationships of bioaccumulative perfluorinated sulfonate (PFSA; C(6), C(8), and C(10) chain lengths) and carboxylate (PFCA; C(6) to C(15) chain lengths) contaminants, as well as precursor compounds including several perfluorinated sulfonamides, and fluorotelomer acids and alcohols, in individual eggs (collected in 2008) from four gull species [glaucous-winged (Larus glaucescens), California (Larus californicus), ring-billed (Larus delawarensis) and herring (Larus argentatus) gulls] from 15 marine and freshwater colony sites in provinces across Canada. The pattern of PFSAs was dominated by perfluorooctane sulfonate (PFOS; >89% of ?PFSA concentration) regardless of egg collection location. The highest ?PFSA concentrations were found in the eggs collected in the urbanized areas in the Great Lakes and the St. Lawrence River area [Big Chicken Island 308 ng/g ww, Toronto Harbour 486 ng/g ww, and Ile Deslauriers (HG) 299 ng/g ww]. Also, eggs from all freshwater colony sites had higher ?PFSA concentrations, which were significant (p<0.05) in many cases, compared to the marine sites with the exception of the Sable Island colony in Atlantic Canada off the coast of Nova Scotia. C(6) to C(15) chain length PFCAs were detected in the eggs, although the pattern was variable among the 15 sites, where PFUnA and PFTrA dominated the pattern for most colonies. Like the ?PFSA, the highest concentrations of ?PFCA were found in the eggs from Big Chicken Island, Toronto Harbour, Ile Deslauriers (HG), and Sable Island, although not all freshwater sites had higher concentrations compared to marine sites. Dietary tracers [?(15)N and ?(13)C stable isotopes (SIs)] revealed that PFSA and PFCA exposure is colony dependent. SI signatures suggested that gulls from most marine colony sites were exposed to PFCs via marine prey. The exception was the Mandarte Island colony in Pacific British Columbia, where PFSA and PFCA exposure appeared to be via terrestrial and/or freshwater prey consumption. The same was true for the freshwater sites where egg SIs suggested both aquatic and terrestrial prey consumption as the source for PFC exposure depending on the colony. Both aquatic (marine and freshwater) and terrestrial prey are likely sources of PFC exposure to gulls but exposure scenarios are colony-specific. PMID:21529948

  1. Selenium and mercury concentrations in California gulls breeding on the Great Salt Lake, Utah, USA.

    PubMed

    Conover, Michael R; Vest, Josh L

    2009-02-01

    We examined selenium (Se) and mercury (Hg) concentrations in adult California gulls (Larus californicus) nesting on the Great Salt Lake, Utah, USA, during 2006 and 2007. During 2006, the mean Se concentration (+/- standard error) was 18.1 +/- 1.5 microg/g in blood on a dry-weight basis and 8.1 +/- 0.4 microg/g in liver. During 2007, Se concentrations were 15.7 +/- 1.5 microg/g in blood and 8.3 +/- 0.4 microg/g in liver; Hg concentrations were 2.4 +/- 0.3 microg/g in blood and 4.1 +/- 0.5 microg/g in liver. Gulls collected from a freshwater colony located within the watershed of the Great Salt Lake had similar levels of Se in the blood and liver as gulls collected on the Great Salt Lake but lower Hg concentrations. Body mass of adult gulls was not correlated with Se or Hg concentrations in their blood or liver. Selenium concentration in California gull eggs collected during 2006 was 3.0 +/- 0.10 microg/g. Of 72 eggs randomly collected from Great Salt Lake colonies, only one was infertile, and none of the embryos exhibited signs of malposition or deformities. We examined 100 newly hatched California gull chicks from Great Salt Lake colonies for teratogenesis; all chicks appeared normal. Hence, the elevated Se and Hg concentrations in adult gulls nesting on the Great Salt Lake did not appear to impair gulls' health or reproductive ability. PMID:18767915

  2. Impact of Salt Pond Restoration on California Gull Displacement and Predation on Breeding Waterbirds

    Microsoft Academic Search

    Josh Ackerman; Jill Bluso-Demers; John Takekawa; Scott Demers; Caitlin Robinson; Collin Eagles-Smith; Nicole Athearn

    The California gull (Larus californicus) population in San Francisco Bay has increased from <200 in 1982 to >46,800 in 2008, and may be negatively affecting nesting waterbirds through harassment, encroachment on nesting sites, and predation on eggs and chicks. The California gull colony at Pond A6 is the largest (>26,000) and is expected to be displaced when this salt pond

  3. PELAGIC RECORDS OF GLAUCOUS-WINGED AND HERRING GULLS IN THE NORTH PACIFIC OCEAN

    Microsoft Academic Search

    GERALD A. SANGER

    GLAUCOUS-WINGED GULLS (Larus glaucescens) and Herring Gulls (L. argentatus) have been sighted sometimes hundreds of miles offshore in the eastern North Pacific Ocean. Yocom (1947) saw both species out to 500 miles off California and Sanger (1965, 1970) noted them to nearly 600 miles off Washington and Oregon, but no pelagic specimens of either species existed (A.O.U., 1957). This paper

  4. Highly carboxylated porphyrins are good biochemical markers of PCB exposure in herring gulls (Larus argentatus)

    SciTech Connect

    Kennedy, S.W.; Fox, G.A.; Trudeau, S.; Bastien, L.J.; Jones, S.P. [Environment Canada, Hull, Quebec (Canada)

    1995-12-31

    The authors have reported that highly carboxylated porphyrins (HCPs) in herring gull livers offer promise as a biochemical marker of exposure of this species to halogenated aromatic hydrocarbons. Here the authors provide evidence from a new study that supports the previous research. HCP concentrations and ethoxyresorufin O-deethylase (EROD) activities were determined in livers of adult gulls (n = 47) that were collected from several colonies on the Great Lakes and from two reference sites. Non-polar extracts were prepared from each liver and were tested for porphyrinogenic and EROD induction potency in an in vitro chicken embryo hepatocyte (CEH) bioassay. The regression between EROD activity in gull livers and EROD induction potency of liver extracts in the CEH bioassay was poor (r{sup 2} = 0.13, p = 0.014); similarly, the regression between EROD activity in gull livers and PCB concentration in liver extracts was poor (r{sup 2} = 0.04, p = 0.19). In contrast, there was a strong linear regression between HCP concentration in gull livers and the porphyrinogenic potency of liver extracts in the CEH bioassay. There was also a strong linear regression between HCP concentration in gull livers and PCB concentration in the extracts. This study, and a large companion study that measured HCPs and chemical residues in herring gulls from 13 colonies (Fox et al., in preparation), indicates that environmental levels of PCBs in several areas of the Great Lakes remain sufficient high to interfere with heme biosynthesis, eliciting elevated HCPs in this species. The authors conclude that HCPs are a good biochemical marker of PCB exposure in herring gulls, but that EROD is not.

  5. Geographic, temporal, and age-specific variation in diets of Glaucous Gulls in western Alaska

    USGS Publications Warehouse

    Schmutz, J.A.; Hobson, K.A.

    1998-01-01

    We collected boluses and food remains of adult Glaucous Gulls (Larus hyperboreus) at or near nests and chicks, and digestive tracts from adults at three sites on the Yukon-Kuskokwim Delta, Alaska that differed in proximity to marine and terrestrial foods. We observed both geographic and temporal variation in diet; gulls consumed proportionately more terrestrial prey after peak hatch in late June, and gulls near the coast consumed proportionately more marine prey than gulls at two inland areas. Goslings occurred in > 60% of all samples from these inland areas. We compared these data to those from a previous study in western Alaska and found no marked differences. Evidence for similar patterns of geographic and temporal variation in diet was found using measurements of stable-carbon and nitrogen isotopes in gull and prey tissues. Stable isotope analysis further revealed that adult gulls consumed proportionately more marine prey (saffron cod, Eleginus gracilis) than they fed to their young. Using isotopic models, we estimated that 7-22% and 10-23% of the diet of adult and juvenile Glaucous Gulls, respectively, was comprised of terrestrial species. In addition to significant age-related variation, dietary estimates varied among geographic areas and between pre- and post-hatch periods. Overall, our isotopic estimates of the contribution of terrestrial prey to the diet of Glaucous Gulls was less than what may be inferred from conventional methods of diet analysis. Our study emphasizes the benefit of combining stable-isotope and conventional analyses to infer temporal and geographic changes in diet of wild birds and other organisms.

  6. The herring gull Larus argentatus as a likely transmitting agent of Salmonella montevideo to sheep and cattle.

    PubMed

    Coulson, J C; Butterfield, J; Thomas, C

    1983-12-01

    This paper presents evidence for the involvement of herring gulls (Larus argentatus) as vectors in the recent outbreaks of Salmonella montevideo in sheep and cattle in Scotland and suggests that the transfer can take place over considerable distances. The breeding area in Scotland of herring gulls which overwinter in N.E. England is remarkably similar to the geographical distribution of the outbreaks. This pattern, together with the feeding behaviour of herring gulls on farmland, the presence of S. montevideo in herring gulls just before their departure from the wintering area and the timing of the return just before the peak of outbreaks are all circumstantial evidence implicating this gull in the outbreaks. The rapid return of these gulls to their breeding areas means that S. montevideo can be transported long distances in one day and raises the possibility that the original source of S. montevideo could have been in N.E. England rather than in Scotland. PMID:6663059

  7. Extended spectrum beta-lactamases detected in Escherichia coli from gulls in Stockholm, Sweden

    PubMed Central

    Wallensten, Anders; Hernandez, Jorge; Ardiles, Karen; González-Acuña, Daniel; Drobni, Mirva; Olsen, Björn

    2011-01-01

    In order to investigate if bacterial antibiotic resistance was present in gull populations in urbanised areas, we conducted a study in which faecal samples from gulls were collected in central Stockholm, Sweden in April and May 2010 and screened for extended spectrum beta-lactamases (ESBL)-type antibiotic resistance. Eighteen of 194 randomly selected Escherichia coli isolates harboured ESBL of CTX-M phenotype. Since the bacteria are unlikely to have developed the resistance in gulls, it may indicate leakage of resistant bacteria to the environment. As many gulls find food and shelter in cities around the world and thereby share their habitat with dense human populations, the finding that as many as 9% of gulls carry ESBL-type antibiotic resistance may imply that zoonotic transmission between gulls, humans, and other animals is likely to occur in such places. This study illustrates how ecologically widespread the problem of antibiotic resistance has become and this has implications for future policy making to reduce the spread of bacteria with antibiotic resistance. PMID:22957123

  8. Isolation and structural characterisation of herring gull (Larus argentatus) pancreatic polypeptide.

    PubMed

    Barton, C L; Shaw, C; Halton, D W; Thim, L

    1994-02-01

    Pancreatic polypeptide (PP) has been isolated from pancreatic extracts of the herring gull (Larus argentatus) using a radioimmunoassay employing an antiserum (PP 221), generated to the conserved C-terminal hexapeptide amide of mammalian PP. Gel permeation and reverse-phase HPLC fractionation of crude pancreatic extracts resolved a single molecular form of gull PP in each case. Purification of gull PP to homogeneity indicated that the mammalian PP antiserum employed was only 4% cross-reactive with this peptide. When radioimmunoassay data were corrected for this, the herring gull pancreas was found to contain 5 nmol PP/g wet wt. The molecular mass of gull PP was determined as 4237 +/- 2 Da by 252Cf plasma desorption mass spectroscopy (PDMS). Gas-phase sequencing established unequivocally the entire primary structure of a 36-amino-acid residue peptide as Gly-Pro-Val-Gln-Pro-Thr-Tyr-Pro-Gly-Asp-Asp-Ala-Pro-Val-Glu-Asp-Leu-Val- Arg-Phe - Try-Asn-Asp-Leu-Gln-Gln-Tyr-Leu-Asn-Val-Val-Thr-Arg-His-Arg-Tyr. The computed molecular mass of this peptide (4235.6 Da) was in close agreement with that derived by PDMS. The primary structure of herring gull PP differs from that of the chicken in four residues at positions 3 (Val/Ser), 18 (Val/IIe), 22 (Asn/Asp), and 23 (Asp/Asn). Avian PP thus appears to be a highly conserved regulatory peptide. PMID:8174930

  9. Organochlorines and possible biochemical effects in glaucous gulls (Larus hyperboreus) from Bjørnøya, the Barents Sea.

    PubMed

    Henriksen, E O; Gabrielsen, G W; Trudeau, S; Wolkers, J; Sagerup, K; Skaare, J U

    2000-02-01

    To study possible biochemical effects of organochlorine contaminants (OCs) in glaucous gulls (Larus hyperboreus), 40 adult individuals were collected from colonies on Bjornoya in the Barents Sea. OCs (four pesticides and nine PCB congeners), microsomal 7-ethoxyresorufin O-deethylase (EROD) activity, microsomal testosterone hydroxylation, highly carboxylated porphyrins (HCPs), retinol, and retinyl palmitate were quantified in liver samples. The hepatic vitamin A stores in glaucous gulls were larger than in herring gulls (Larus argentatus) from other studies conducted in contaminated locations in North America. No significant relationships were found between liver retinoid concentrations and OC levels. The hepatic EROD activity was low compared to other studies on fish-eating birds and only marginally associated with PCB levels. Microsomal testosterone hydroxylase activity was only observed at the 6beta-position and could not be related to OC levels. The low P450-associated enzyme activities in the glaucous gull suggests that they have a low capacity for metabolizing OCs, which may contribute to the high accumulation of OCs in this species. HCPs were only elevated (138 pmol g(-1)) in the sample with highest OC levels, whereas the remaining samples contained low levels of HCPs (<30 pmol g(-1)). The weak association between EROD activity and PCB levels and the low level of HCPs suggest that these biochemical parameters were unaffected by OCs in most of the sampled gulls. Thus, the glaucous gull seems not to be particularly sensitive toward Ah-receptor mediated effects. PMID:10629287

  10. Gull contributions of phosphorus and nitrogen to a Cape Cod kettle pond

    USGS Publications Warehouse

    Portnoy, J.W.; Soukup, M.A.

    1990-01-01

    Nutrient excretion rates and the annual contribution of P from the feces of the gulls Larus argentatus and L. marinus (and of N from L. argentatus) to the nutrient budget of Gull Pond (Wellfleet), a soft water seepage lake, have been estimated. Intensive year-round gull counts by species were combined with determinations of defecation rate and the nutrient content of feces to quantitatively assess the P loading rates associated with regular gull use of this coastal pond on a seasonal and annual basis. Total P loading from gulls was estimated to be 52 kg yr?1, with 17 kg from L. argentatus and 35 kg from L. marinus, resulting from about 5.0 ? 106 h yr?1 and 1.7 ? 106 h yr?1 of pond use. This compares with P loading estimates of 67 kg yr?1 from upgradient septic systems, 2 kg yr?1 from precipitation and 3 kg yr?1 from unpolluted ground water. Fifty-six percent of annual gull P loading was associated with migratory activity in late fall. Estimated annual N loading by L. argentatus was 14 kg TKN, 206 g NO3-N, and 1.85 g g NH3-N.

  11. Quantifying fall migration of Ross's gulls (Rhodostethia rosea) past Point Barrow, Alaska

    USGS Publications Warehouse

    Uher-Koch, Brian D.; Davis, Shanti E.; Maftei, Mark; Gesmundo, Callie; Suydam, R.S.; Mallory, Mark L.

    2014-01-01

    The Ross's gull (Rhodostethia rosea) is a poorly known seabird of the circumpolar Arctic. The only place in the world where Ross's gulls are known to congregate is in the near-shore waters around Point Barrow, Alaska where they undertake an annual passage in late fall. Ross's gulls seen at Point Barrow are presumed to originate from nesting colonies in Siberia, but neither their origin nor their destination has been confirmed. Current estimates of the global population of Ross's gulls are based largely on expert opinion, and the only reliable population estimate is derived from extrapolations from previous counts conducted at Point Barrow, but these data are now over 25 years old. In order to update and clarify the status of this species in Alaska, our study quantified the timing, number, and flight direction of Ross's gulls passing Point Barrow in 2011. We recorded up to two-thirds of the estimated global population of Ross's gulls (? 27,000 individuals) over 39 days with numbers peaking on 16 October when we observed over 7,000 birds during a three-hour period.

  12. Migration patterns of Common Gulls Larus canus ringed in the non?breeding season in Copenhagen and the surrounding area

    Microsoft Academic Search

    K. T. Pedersen; E. B. Fritze; S. P. Kharitonov

    2000-01-01

    In the greater Copenhagen area (54°59'?56°07'N, 11°55'12°40'E) 4899 Common Gulls were ringed from September to April in 1976 to 1993. Up to 31 December 1993, 11,824 ring?recoveries from 2,388 gulls (49% of the total number ringed) had been received. Copenhagen lies on the Common Gull migration route from northeastern to western Europe. The directions of migration are southwest in autumn

  13. Weathered oil: effect on hatchability of heron and gull eggs

    SciTech Connect

    Macko, S.A. (Port Aransas Marine Lab., TX); King, S.M.

    1980-08-01

    Contact with weathered oil seems more likely for waterbirds than contact with fresh oil; however, the effects of weathered oil on embryo survival have only partially been explored. Results of one study showed that 20 ..mu..L of 4 week-old crude oil applied to the eggshell surface caused a significant decrease in embryo survival of mallard (Anas platyrhynchos) eggs. In that study, oil was weathered under laboratory conditions using fresh water. To our knowledge, there have been no tests to determine the effects on egg hatchability of oil naturally weathered in marine habitats. The present study assesses the effects of external applications of naturally weathered crude oil on embryo survival of Louisiana heron (Hydranassa tricolor) and laughing gull (Larus atricilla) eggs.

  14. Spatio-Temporal Structure of Hooded Gull Flocks

    PubMed Central

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Hayakawa, Yoshinori

    2013-01-01

    We analyzed the spatio-temporal structure of hooded gull flocks with a portable stereo camera system. The 3-dimensional positions of individuals were reconstructed from pairs of videos. The motions of each individual were analyzed, and both gliding and flapping motions were quantified based on the velocity time series. We analyzed the distributions of the nearest neighbor’s position in terms of coordinates based on each individual’s motion. The obtained results were consistent with the aerodynamic interaction between individuals. We characterized the leader-follower relationship between individuals by a delay time to mimic the direction of a motion. A relation between the delay time and a relative position was analyzed quantitatively, which suggested the basic properties of the formation flight that maintains order in the flock. PMID:24339960

  15. Atlantic Deep-water Response to the Early Pliocene Shoaling of the Central American Seaway

    PubMed Central

    Bell, David B.; Jung, Simon J. A.; Kroon, Dick; Hodell, David A.; Lourens, Lucas J.; Raymo, Maureen E.

    2015-01-01

    The early Pliocene shoaling of the Central American Seaway (CAS), ~4.7–4.2 million years ago (mega annum-Ma), is thought to have strengthened Atlantic Meridional Overturning Circulation (AMOC). The associated increase in northward flux of heat and moisture may have significantly influenced the evolution of Pliocene climate. While some evidence for the predicted increase in North Atlantic Deep Water (NADW) formation exists in the Caribbean and Western Atlantic, similar evidence is missing in the wider Atlantic. Here, we present stable carbon (?13C) and oxygen (?18O) isotope records from the Southeast Atlantic-a key region for monitoring the southern extent of NADW. Using these data, together with other ?13C and ?18O records from the Atlantic, we assess the impact of the early Pliocene CAS shoaling phase on deep-water circulation. We find that NADW formation was vigorous prior to 4.7 Ma and showed limited subsequent change. Hence, the overall structure of the deep Atlantic was largely unaffected by the early Pliocene CAS shoaling, corroborating other evidence that indicates larger changes in NADW resulted from earlier and deeper shoaling phases. This finding implies that the early Pliocene shoaling of the CAS had no profound impact on the evolution of climate. PMID:26193070

  16. Diets of nestling gull-billed terns in coastal Virginia

    USGS Publications Warehouse

    Erwin, R.M.; Eyler, T.B.; Hatfield, J.S.; McGary, S.

    1998-01-01

    We studied the diets of nestling Gull-billed Terns (Sterna nilotica) at colonies in coastal Virginia during the breeding seasons of 1995 and 1996 as part of a long-term study of the species. No previous quantitative assessments had been made of diets of this species anywhere along the Atlantic Coast, and only a few observations had been reported from other coastal areas in the southern United States. During 80 h of observations over the two seasons, 757 feeding observations were made, primarily at two colony sites. We examined how prey type (fish, marine invertebrates, terrestrial prey) and size were influenced by year, tide cycle, season (early and late) and age of the young (small chicks 7 d). We did not find significant year differences, but all other factors revealed statistically significant results. Older (>7 d) chicks were fed relatively more terrestrial and marine invertebrate prey than were younger chicks. In June (early season), fewer fish and terrestrial prey were fed to chicks than later (July-August). Most prey were less than one bill length in size, with the majority of the smallest prey being marine invertebrates. Tide cycle influenced prey delivered with terrestrial prey becoming relatively more important during high and ebb periods than during low and flood tides when aquatic prey dominated. The major marine invertebrate prey taken was the fiddler crab (Uca spp.). Terrestrial prey consisted mostly of large odonates and orthopterans. Unlike earlier reports from Europe, we found no regurgitated food pellets in any of the colonies in either year. This study confirms that the Gull-billed Tern is an extremely opportunistic feeder and has adapted to a variety of habitats, helping to explain its cosmopolitan distribution.

  17. Determination of non-halogenated, chlorinated and brominated organophosphate flame retardants in herring gull eggs based on liquid chromatography-tandem quadrupole mass spectrometry.

    PubMed

    Chen, Da; Letcher, Robert J; Chu, Shaogang

    2012-01-13

    Numerous triester organophosphate flame retardants (OPFRs) have been used for several decades and continue to be used in a variety of commercial products. We developed a sensitive quantitative method for the analysis of, seven non-halogenated, three chlorinated and two brominated OPFRs of known or possible environmental relevance in herring gull eggs. This method is based on a simple two-step sample extraction followed by liquid chromatography-electrospray ionization(+)-tandem mass spectrometry. Instrumental detection limits and method limits of quantification (MLOQs) among the 12 OPFRs ranged from 0.01 to 0.12 ng/mL and 0.06 to 0.20 ng/g, respectively. The mean OPFR recovery efficiencies of replicate analyses (n=6) were very quantitative and ranged from 89% to 104%, with the two brominated OPFRs being somewhat lower but reproducible, i.e., 67% and 72%, respectively. Essentially negligible matrix effects were indicated by a standard addition approach that revealed mean percent signal recoveries (n=5 replicates) of 89-106% for most OPFRs. In the analysis of n=13 herring gull eggs from the Channel-Shelter Island colony (Lake Huron), tris(2-chloroisopropyl) phosphate (

  18. Comparisons of remotely-retrieved directional wave spectra over a large area with a shoaling-wave model

    Microsoft Academic Search

    J. Z. Williams; J. P. Dugan; C. C. Piotrowski; J. M. Kaihatu

    2005-01-01

    Validation and development of shoaling-wave models generally rely on measurements from buoys or pressure arrays to characterize the wavefield. However, these sensors provide single-point or localized measurements and do not give any insight into the transformation of the wavefield across the shoaling region. As such, a model that is adjusted for favorable comparison with these localized measurements could inadvertently misrepresent

  19. Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves E. L. SHROYER, J. N. MOUM, AND J. D. NASH

    E-print Network

    Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves E. L. SHROYER, J. N. MOUM coast document the shoaling of three groups of nonlinear internal waves of depression over 35 km across of stratification and velocity. 1. Introduction The role of nonlinear internal waves (NLIWs) in the coastal ocean

  20. Internal solitary waves of elevation advancing on a shoaling shelf Jody M. Klymak and James N. Moum

    E-print Network

    Internal solitary waves of elevation advancing on a shoaling shelf Jody M. Klymak and James N. Moum: 4544 Oceanography: Physical: Internal and inertial waves; 4219 Oceanography: General: Continental shelf: Klymak, J. M., and J. N. Moum, Internal solitary waves of elevation advancing on a shoaling shelf

  1. Bathymetry of Stevens Creek and Neal Shoals reservoirs, South Carolina, 1990

    USGS Publications Warehouse

    Stringfield, W.J.

    1995-01-01

    Stevens Creek Reservoir and Neal Shoals Reservoir are located in the Piedmont Province of South Carolina (fig. 1). The primary purposes for the reservoirs are hydroelectric power generation and recreational activities. Because there has been no bottom surveys of these reservoirs since they were formed in the early 1900's, there is concern about the decrease in reservoir volumes due to sedimen- tation. An investigation was begun in 1990 by the U.S. Geological Survey (USGS) in cooperation with the South Carolina Department of Natural Resources, Water Resources Division to provide information on present water depths, on areas of rapid-sediment deposition, and on changes in lake volume. This report documents the bathymetric surveys made of Stevens Creek and Neal Shoals Reservoirs during 1990 and provides maps that depict the depth of each reservoir. This report documents the bathymetric surveys made of Stevens Creek and Neal Shoals Reservoirs during 1990 and provides maps that depict the depth of each reservoir.

  2. 75 FR 71731 - Notice of Availability of the Record of Decision for the Harvest of Glaucous-Winged Gull Eggs by...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ...Park without impairing the biological sustainability of the Park's glaucous-winged...basis without impairing the biological sustainability of the sea gull population in the...occur without impairing the biological sustainability of the gull population in the...

  3. Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test

    SciTech Connect

    K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

    2004-03-01

    Groundwater flow and radionuclide transport at the Shoal underground nuclear test are characterized using three-dimensional numerical models, based on site-specific hydrologic data. The objective of this modeling is to provide the flow and transport models needed to develop a contaminant boundary defining the extent of radionuclide-contaminated groundwater at the site throughout 1,000 years at a prescribed level of confidence. This boundary will then be used to manage the Project Shoal Area for the protection of the public and the environment.

  4. Corrective action investigation plan for Project Shoal Area CAU No. 416

    SciTech Connect

    NONE

    1996-08-01

    This Corrective Action Investigation Plan (CAIP) is part of an ongoing US Department of Energy (DOE)-funded project for the investigation of Corrective Action Unit (CAU) No. 416, Project Shoal Area (PSA). Project Shoal was conducted to determine whether seismic waves produced by underground nuclear testing could be differentiated from naturally occurring earthquakes. The PSA site is located approximately 30 miles southeast of Fallon, Nevada, in the northern portion of Sand Springs Mountains in Churchill County. This CAIP will be implemented in accordance with the Federal Facility Agreement and Consent Order, the Industrial Sites Quality Assurance Project Plan, and all applicable Nevada Division of Environmental Protection policies and regulations.

  5. Regressive and transgressive barrier islands on the North-Central Gulf Coast — Contrasts in evolution, sediment delivery, and island vulnerability

    NASA Astrophysics Data System (ADS)

    Otvos, Ervin G.; Carter, Gregory A.

    2013-09-01

    Basic differences between non-deltaic regressive and deltaic transgressive barrier islands reflect major contrasts in geological settings and sediment sources. Two island groups on the N. Gulf of Mexico provide unique perspectives of genetic and geomorphic contrasts applicable in a worldwide context. The near-extinction of the deltaic transgressive Chandeleur barriers and reduction of the sturdier prograded Mississippi-Alabama (MS-AL) chain are related to differences in sediment sources, storm, and anthropogenic impact. 160 years of documentary evidence points to contrasting geological settings, development history, sediment sources, and island morphology as responsible for different island erodibility and life spans. The non-deltaic chain received larger volumes of coarser, less erodible medium sand from the NE Gulf coast. Onshore sand flux from reworked delta deposits received from the retreating delta shoreface initiated the fragile, thin, and isolated transgressive Chandeleur islands. Fine-grained sand from unconsolidated muds of abandoned Mississippi-St. Bernard delta lobes maintained two distinct transgressive barrier island categories. In the absence of quantitative data on cross-shore transport, discrepancies between estimated littoral drift volumes and sand reserves for nourishment remain unexplained. Medium-sandy MS-AL barriers have resisted storm events far better than delta barriers. However, even the former chain did undergo 26 to 53% area reduction since 1848. Anthropogenic intervention stymied island growth. Emerging intertidal berm-basins formed on sandy shoal platforms in storm-eliminated sectors have contributed to partial island recovery. Delta attrition by wave erosion, tectonic, and compactional subsidence had accelerated delta lobe and barrier island decay. Intensive storm erosion culminating in and following Hurricane Katrina came close to eradicate the highly vulnerable Chandeleur barrier chain. Lacking adequate nourishment, after devastating cyclones only small islands reemerge and persist temporarily from the shoal belt. A four-stage barrier evolution model, globally applicable to transgressive deltaic barriers, is based on documented changes in late Holocene Mississippi sub-deltas.

  6. Fluoride exposure and selected characteristics of eggs and bones of the herring gull (Larus argentatus) and the common gull (Larus canus).

    PubMed

    Vikøren, T; Stuve, G

    1996-04-01

    Fluorine concentrations were determined in the shell of 285 herring gull eggs (Larus argentatus) and 120 common gull eggs (Larus canus), collected May 1991 to 1993, from breeding colonies exposed to emissions from two Norwegian primary aluminum smelters located at Karmøy and Sunndal, and from unexposed reference localities in Eigersund, Sola, and Stavanger. Volume-index, shell thickness, thickness-index, and fertilization of the eggs also were monitored. In both species, the shell fluorine concentration was significantly increased in eggs collected at sites exposed to fluoride emissions. No effects on other egg characteristics were observed. In both exposed and unexposed sites, the last-laid egg in a clutch, normally containing three eggs, had the highest shell fluorine residue. Fluorine levels also were analyzed in femurs from 42 herring gulls, collected from Karmøy and Sola in May 1993. The relationship between sex and fluoride accumulation, and the relations between fluorine concentration in femurs of laying herring gulls and in the shell of their eggs, were evaluated. Bone morphology also was studied. Bone fluorine concentrations were raised significantly in emission-exposed female birds. Moreover, females from the exposed site had significantly higher fluorine residues than males. There was a positive correlation between fluorine levels in femurs of individual laying birds and those in the shells of their eggs. No changes in bone morphology due to fluoride exposure was found. PMID:8722255

  7. Evolution of a reassortant North American gull influenza virus lineage: drift, shift and stability

    USGS Publications Warehouse

    Hall, Jeffrey S.; TeSlaa, Joshua L.; Nashold, Sean W.; Halpin, Rebecca A.; Stockwell, Timothy; Wentworth, David E.; Dugan, Vivien; Ip, Hon S.

    2013-01-01

    Background: The role of gulls in the ecology of avian influenza (AI) is different than that of waterfowl. Different constellations of subtypes circulate within the two groups of birds and AI viruses isolated from North American gulls frequently possess reassortant genomes with genetic elements from both North America and Eurasian lineages. A 2008 isolate from a Newfoundland Great Black-backed Gull contained a mix of North American waterfowl, North American gull and Eurasian lineage genes. Methods: We isolated, sequenced and phylogenetically compared avian influenza viruses from 2009 Canadian wild birds. Results: We analyzed six 2009 virus isolates from Canada and found the same phylogenetic lineage had persisted over a larger geographic area, with an expanded host range that included dabbling and diving ducks as well as gulls. All of the 2009 virus isolates contained an internal protein coding set of genes of the same Eurasian lineage genes except PB1 that was from a North American lineage, and these genes continued to evolve by genetic drift. We show evidence that the 2008 Great Black-backed Gull virus was derived from this lineage with a reassortment of a North American PA gene into the more stable core set of internal protein coding genes that has circulated in avian populations for at least 2 years. From this core, the surface glycoprotein genes have switched several times creating H13N6, H13N2, and H16N3 subtypes. These gene segments were from North American lineages except for the H16 and N3 vRNAs. Conclusions: This process appears similar to genetic shifts seen with swine influenza where a stable "triple reassortant internal gene" core has circulated in swine populations with genetic shifts occurring with hemaggluttinin and neuraminidase proteins getting periodically switched. Thus gulls may serve as genetic mixing vessels for different lineages of avian influenza, similar to the role of swine with regards to human influenza. These findings illustrate the need for continued surveillance in gull and waterfowl populations, both on the Pacific and especially Atlantic coasts of North America, to document virus intercontinental movement and the role of gull species in the evolution and epidemiology of AI.

  8. SURFACE CURRENTS OF LAKE MICHIGAN 1931 AND 1932

    E-print Network

    and Wildlife Service Special Scientific Report- -Fisheries No. 413 Washington, D. C. 1963 #12;#12;CONTENTS Page to Grand Haven 19 Frankfort to Two Rivers to nets 21 Frankfort to Kewaunee 23 Kewaunee to Port Washington Gull Island to Manistique 34 Charlevoix to Dahlia Shoal and northwest of Charlevoix 36 General

  9. Monitoring organic contaminants in eggs of glaucous and glaucous-winged gulls ( Larus hyperboreus and Larus glaucescens) from Alaska

    Microsoft Academic Search

    Stacy S. Vander Pol; Paul R. Becker; Michael B. Ellisor; Amanda J. Moors; Rebecca S. Pugh; David G. Roseneau

    2009-01-01

    Gull eggs have been used to monitor contaminants in many parts of the world. The Seabird Tissue Archival and Monitoring Project (STAMP) is a long-term program designed to track trends in pollutants in northern marine environments using seabird eggs. Glaucous and glaucous-winged gull (Larus hyperboreus and Larus glaucescens) eggs collected in 2005 from seven Alaskan colonies were analyzed for organic

  10. Screening of thyroid gland histology in organohalogen-contaminated glaucous gulls (Larus hyperboreus) from the Norwegian Arctic

    Microsoft Academic Search

    Christian Sonne; Jonathan Verreault; Geir W. Gabrielsen; Robert J. Letcher; Pall S. Leifsson; Tine Iburg

    2010-01-01

    The associations between blood organohalogen contaminant (OHC) concentrations and thyroid gland histology were studied in 10 adult female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic (Bjørnøya) during the incubation period. This histological investigation was undertaken as previous glaucous gull studies from the same area reported negative relationships between circulating OHC concentrations and thyroid hormone levels. Organohalogen concentrations have previously

  11. Recombinant Transthyretin Purification and Competitive Binding with Organohalogen Compounds in Two Gull Species (Larus argentatus and Larus hyperboreus)

    Microsoft Academic Search

    Francisco Ucan-Marõ; Augustine Arukwe; Anne Mortensen; Geir W. Gabrielsen; Glen A. Fox; Robert J. Letcher

    2009-01-01

    Glaucous gulls (Larus hyperboreus) from Svalbard, Norway (marine), and herring gulls (Larus argentatus) from the Lau- rentian Great Lakes (freshwater) of North America are differen- tially exposed to persistent and bioaccumulative anthropogenic contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ether (PBDE) flame retardants and metabolic products. Such compounds can potentially perturb hormone transport via binding interactions with proteins

  12. Intraspecific Variation in Trophic Feeding Levels and Organochlorine Concentrations in Glaucous Gulls ( Larus hyperboreus ) from Bjørnøya, the Barents Sea

    Microsoft Academic Search

    Kjetil Sagerup; Espen O. Henriksen; Janneche U. Skaare; Geir W. Gabrielsen

    2002-01-01

    Biomagnification contributes to high concentrations of persistent organochlorines (OC) in some Arctic vertebrates. Glaucous gulls (Larus hyperboreus) on Bjørnøya in the western Barents Sea were studied to compare the intraspecific variation in OC concentration with variation in trophic feeding levels, estimated from ratios of nitrogen isotopes. Liver tissue samples from 40 adult glaucous gulls were analysed for hexachlorobenzene (HCB), oxychlordane,

  13. Colonization and population growth of Yellow-legged Gull Larus cachinnans in southeastern Poland: causes and influence on native species

    Microsoft Academic Search

    PIOTR SKORKA; JOANNA D. WOJCIK; RAFAL MARTYKA

    2005-01-01

    The Yellow-legged Gull Larus cachinnans was first recorded in Poland in the 1980s. We analysed the probable factors responsible for its successful colonization of new areas. We also expected that such a large species should affect populations of other colonial waterbirds. We studied the breeding and feeding ecology in the largest inland colony of the Yellow- legged Gull in Poland,

  14. PIECES OF SILVER: EXAMPLES OF THE ECONOMIC IMPACT AND MANAGEMENT OF THE SILVER GULL (LARUS NOVAEHOLLANDIAE) IN MELBOURNE, AUSTRALIA

    Microsoft Academic Search

    IAN D. TEMBY

    Like a number of gull species, the silver gull Larus novaehollandiae has expanded its population in response to human food subsidy. The major anthropogenic food source is food waste at rubbish tips. Other sources of human food waste are also exploited. Many problems result from the activities of these birds, including human health and safety, economic impacts, and effects on

  15. Chiral organochlorine contaminants in blood and eggs of glaucous gulls (Larus hyperboreus) from the Norwegian Arctic.

    PubMed

    Ross, Matthew S; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Wong, Charles S

    2008-10-01

    Glaucous gulls (Larus hyperboreus) and their eggs from Svalbard (Norwegian Arctic) have been used as biomonitors of contaminants in the marine environment. In this study, the enantiomer fractions (EFs) of chiral chlordanes and atropisomeric polychlorinated biphenyl (PCB) congeners were determined in the blood plasma of adult male and female glaucous gulls from three breeding colonies in Svalbard. Plasma EFs were similar in magnitude and direction to EFs previously reported in glaucous gulls from other arctic food webs, suggesting overall similarities in the biochemical processes influencing the EFs of bioaccumulated organochlorine (OC) contaminants within the food webs at those locations. Additionally, EFs in yolk of eggs collected concurrently from within the same nesting colonies varied with location, laying date, and OC concentrations, and may be influenced by changes in the local feeding ecology between those colonies. No differences were found between the EFs for any analyte in female gulls compared to those found in egg yolk, indicating that processes involved in the maternal transfer of chlordanes and PCBs to eggs do not modulate the stereochemical ratio between enantiomers. Therefore, the use of eggs as a valuable and noninvasive means of OC biomonitoring may also extend to enantiomer compositions in glaucous gulls, and perhaps also in other seabird species from arctic regions. PMID:18939544

  16. An outbreak of type C botulism in Herring Gulls (Larus argentatus) in Southeastern Sweden

    USGS Publications Warehouse

    Neimanis, A.; Gavier-Widen, D.; Leighton, F.; Bollinger, T.; Rocke, T.; Morner, T.

    2007-01-01

    From 2000 to 2004, over 10,000 seabirds, primarily Herring Gulls (Larus argentatus), died from an undetermined cause in the Blekinge archipelago in southeastern Sweden. In June 2004, 24 affected Herring Gulls were examined clinically, killed humanely, and 23 were examined by necropsy. Seven and 10 unaffected Herring Gulls collected from a local landfill site and from Iceland, respectively, served as controls. All affected birds showed similar neurologic signs, ranging from mild incoordination and weakness to severe flaccid paralysis of legs and wings, but generally were alert and responsive. All affected gulls were in normal nutritional condition, but were dehydrated and had empty stomachs. No gross or microscopic lesions, and no bacterial or viral pathogens were identified. Type C botulinum toxin was detected in the sera of 11 of 16 (69%) affected gulls by mouse inoculation. Type C botulism was the proximate cause of disease in 2004. Sera from 31% of birds tested from outbreaks in 2000 to 2003 also had detectable type C botulinum toxin by mouse inoculation. No large-scale botulism outbreak has been documented previously in this area. The source of toxin, initiating conditions, and thus, the ultimate cause of this outbreak are not known. This epidemic might signal environmental change in the Baltic Sea. ?? Wildlife Disease Association 2007.

  17. Metals and radionuclides in birds and eggs from Amchitka and Kiska Islands in the Bering Sea/Pacific Ocean ecosystem.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2007-04-01

    Metals and radionuclide levels in marine birds of the Aleutians are of interest because they are part of subsistence diets of the Aleut people, and can also serve as indicators of marine pollution. We examined geographic and species-specific variations in concentrations of radionuclides in birds and their eggs from Amchitka, the site of underground nuclear tests from 1965 to 1971, and Kiska Islands (a reference site) in the Aleutians, and the levels of lead, mercury and cadmium in eggs. In 2004 we collected common eiders (Somateria mollissima), tufted puffins (Fratercula cirrhata), pigeon guillemot (Cepphus columba) and glaucous-winged gulls (Larus glaucescens) from Amchitka and Kiska, and eggs from eiders and gulls from the two island. We also collected one runt bald eagle (Haliaeetus leucocephalus) chick from both Amchitka and Kiska Islands. For most species, the levels of radionuclide isotopes were below the minimum detectable activity levels (MDA). Out of 74 cesium-137 analyses, only one composite (gulls) was above the MDA, and out of 14 composites tested for plutonium (Pu-239, 240), only one exceeded the MDA (a guillemots). Three composites out of 14 tested had detectable uranium-238. In all cases, the levels were low and close to the MDAs, and were below those reported for other seabirds. There were significant interspecific differences in metal levels in eggs: gulls had significantly higher levels of cadmium and mercury than the eiders, and eiders had higher levels of lead than gulls. There were few significant differences as a function of island, but eiders had significantly higher levels of cadmium in eggs from Kiska, and gulls had significantly higher levels of mercury on Kiska. The levels of cadmium and mercury in eggs of eiders and gulls from this study were above the median for cadmium and mercury from studies in the literature. The levels of mercury in eggs are within the range known to affect avian predators, but seabirds seem less vulnerable to mercury than other birds. However, the levels of mercury are within the action levels for humans, suggesting some cause for concern if subsistence Aleuts eat a large quantity of eggs. PMID:17206460

  18. Changes in Caribbean surface hydrography during the Pliocene shoaling of the Central American Seaway

    E-print Network

    Gilli, Adrian

    Changes in Caribbean surface hydrography during the Pliocene shoaling of the Central American planktonic foraminifers from the Caribbean (Ocean Drilling Program sites 999 and 1000), the tropical east Bank) were used to examine Atlantic-Caribbean-Pacific atmospheric and oceanic linkages associated

  19. Statistical classification methodology of SHOALS 3000 backscatter to mapping coastal benthic habitats

    E-print Network

    Long, Bernard

    -- The Scanning Hydrographic Operational Airborne LiDAR Survey (SHOALS) consists of a bathymetric LiDAR system; multivariate analysis; habitat classification I. INTRODUCTION Airborne laser (or LiDAR) bathymetry (ALB-habitat view, while they are (2) different between themselves. Keywords-components: bathymetric LiDAR; waveform

  20. Progressive shoaling of the equatorial Pacific thermocline over the last eight glacial periods

    NASA Astrophysics Data System (ADS)

    Regoli, Fabienne; Garidel-Thoron, Thibault; Tachikawa, Kazuyo; Jian, Zhiming; Ye, Liming; Droxler, André W.; Lenoir, Guillaume; Crucifix, Michel; Barbarin, Nicolas; Beaufort, Luc

    2015-05-01

    The depth of equatorial Pacific thermocline is diagnostic of the main modes of tropical climates. Past estimates of Pacific thermocline dynamics have been reconstructed either for the Last Glacial Maximum or on longer timescales at low resolution. Here we document a new high-resolution set of reconstructed past sea surface and subsurface waters temperatures from the southwestern subequatorial Pacific, core MD05-2930, in the Gulf of Papua, over the last 800 ka. We used two morphotypes of Globigerinoides ruber known to live at different water depths to reconstruct past stratification. We estimated calcification temperature of each morphotypes by Mg/Ca paleothermometry. Our subequatorial Pacific thermocline paleotemperature record indicates a response of the thermocline to both direct orbital forcing and glacial-interglacial changes. Our stratification record shows a systematic shallower glacial thermocline, whereas sea surface temperatures are characterized by precessional forcing. The record is indicative of a progressive long-term shoaling of the thermocline during the glacial stages during the late Pleistocene. The shoaling of the subequatorial Pacific thermocline is consistent with regional estimates. An enhanced South Pacific shallow overturning wind-driven circulation could have driven this progressive shoaling. We speculate that this late Pleistocene glacial shoaling of the thermocline could be related to an increase in the amplitude of the obliquity.

  1. Shifting reproductive success in a shoal of Atlantic Cod, Gadus morhua L.

    E-print Network

    Hutchings, Jeffrey A.

    Shifting reproductive success in a shoal of Atlantic Cod, Gadus morhua L. Jon Egil Skjæraasen behaviour of Atlantic Cod (Gadus morhua L.) was examined by studying wild and reared individuals from of male Atlantic Cod. We suggest that this hypothesis merits further study. Keywords Mating system

  2. Storm impact and evolution of a mangrove-fringed chenier plain, Shoal Bay, Darwin, Australia

    Microsoft Academic Search

    C. D. Woodroffe; D. Grime

    1999-01-01

    Storms are considered to have significant impacts on the development of chenier plains, particularly through the devastation of mangrove vegetation, but also in terms of winnowing sand and shell from mudflats and forming chenier ridges. Shoal Bay, in the Beagle Gulf, northern Australia, contains a small chenier plain, which was struck by a severe tropical cyclone, Cyclone Tracy, on Christmas

  3. Response of individual shoaling Atlantic cod to ocean currents on the northeast Newfoundland Shelf

    E-print Network

    deYoung, Brad

    Response of individual shoaling Atlantic cod to ocean currents on the northeast Newfoundland Shelf Group, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, N¯d., Canada A1B 3X7 b Fisheries Conservation Chair, Marine Institute, Memorial University of Newfoundland, St. John's, N

  4. Pressuregradientdriven nearshore circulation on a beach influenced by a large inlettidal shoal system

    E-print Network

    Kirby, James T.

    that wave refraction over the ebb tidal shoal causes wave focusing toward a narrow region at Ocean Beach system F. Shi,1 D. M. Hanes,2 J. T. Kirby,1 L. Erikson,2 P. Barnard,2 and J. Eshleman2 Received 9 model, it is found that the nearshore circulation is significantly affected by the heterogeneous wave

  5. Shoaling of nonlinear internal waves in Massachusetts Bay A. Scotti,1

    E-print Network

    Pineda, Jesús

    Shoaling of nonlinear internal waves in Massachusetts Bay A. Scotti,1 R. C. Beardsley,2 B. Butman,3 obtained during the August 1998 Massachusetts Bay Internal Wave Experiment and observations from a shorter] While modeling and observations of propagating non- linear internal waves (NLIWs) in the ocean (both

  6. Evaluation of groundwater flow and transport at the Shoal underground nuclear test: An interim report

    SciTech Connect

    Pohll, G.; Chapman, J.; Hassan, A.; Papelis, C.; Andricevic, R.; Shirley, C.

    1998-07-01

    Since 1962, all United States nuclear tests have been conducted underground. A consequence of this testing has been the deposition of large amounts of radioactive materials in the subsurface, sometimes in direct contact with groundwater. The majority of this testing occurred on the Nevada Test Site, but a limited number of experiments were conducted in other locations. One of these is the subject of this report, the Project Shoal Area (PSA), located about 50 km southeast of Fallon, Nevada. The Shoal test consisted of a 12-kiloton-yield nuclear detonation which occurred on October 26, 1963. Project Shoal was part of studies to enhance seismic detection of underground nuclear tests, in particular, in active earthquake areas. Characterization of groundwater contamination at the Project Shoal Area is being conducted by the US Department of Energy (DOE) under the Federal Facility Agreement and Consent Order (FFACO) with the State of Nevada Department of Environmental Protection and the US Department of Defense (DOD). This order prescribes a Corrective Action Strategy (Appendix VI), which, as applied to underground nuclear tests, involves preparing a Corrective Action Investigation Plan (CAIP), Corrective Action Decision Document (CADD), Corrective Action Plan, and Closure Report. The scope of the CAIP is flow and transport modeling to establish contaminant boundaries that are protective of human health and the environment. This interim report describes the current status of the flow and transport modeling for the PSA.

  7. Depth inversion for nonlinear waves shoaling over a barred-beach 1

    E-print Network

    Grilli, Stéphan T.

    to model the wave height variation, and thus predict koHo, in the depth-inversion problem. FollowingDepth inversion for nonlinear waves shoaling over a barred-beach 1 St´ephan T. Grilli 2 , M. ASCE, email : jes@dhi.dk 1 #12;1997]. Grilli (1998), however, studied the depth inversion problem for mildly

  8. UV matters in shoaling decisions Ricarda Modarressie*, Ingolf P. Rick and Theo C. M. Bakker

    E-print Network

    (K) filters used, control experiments with neutral-density optical filters were performed in order to clarify environment, suggesting a potential trade-off between UV radiation and lower brightness during shoal choice to the human eye is not necess- arily equivalent to what animals can perceive, because visual systems can

  9. Nesting biology of laughing gulls Larus atricilla in relation to agricultural chemicals in south Texas USA 1978-1981

    USGS Publications Warehouse

    White, D.H.; Mitchell, C.A.; Prouty, R.M.

    1983-01-01

    Various aspects of the breeding biology of Laughing Gulls (Larus atricilla) have been studied extensively in Florida (Dinsmore and Schreiber 1974, Schreiber et al. 1979, Schreiber and Schreiber 1980), New Jersey (Bongiorno 1970, Burger and Beer 1976, Burger 1976, Montevecchi 1978), and Massachusetts (Noble and Wurm 1943), but little is known of their yearly fledging success in Texas or elsewhere. The Laughing Gull is a common colonial nester along most of the Texas coast, second only to the Cattle Egret (Bubulcus ibis) in breeding abundance; however, the Laughing Gull may be threatened in Texas because of suspected declines at certain traditional nesting locales (Blacklock et al. 1979). Since Laughing Gulls often nest in proximity to agricultural and industrial areas, we were concerned that environmental pollutants might be adversely affecting productivity. In 1978-1981 we conducted studies along the south Texas coast to learn more about the nesting ecology of Laughing Gulls and to evaluate the effects of environmental contaminants on reproduction.

  10. Analysis of the Gull Fecal Microbial Community Reveals the Dominance of Catellicoccus marimammalium in Relation to Culturable Enterococci

    PubMed Central

    Koskey, Amber M.; Fisher, Jenny C.; Traudt, Mary F.; Newton, Ryan J.

    2014-01-01

    Gulls are prevalent in beach environments and can be a major source of fecal contamination. Gulls have been shown to harbor a high abundance of fecal indicator bacteria (FIB), such as Escherichia coli and enterococci, which can be readily detected as part of routine beach monitoring. Despite the ubiquitous presence of gull fecal material in beach environments, the associated microbial community is relatively poorly characterized. We generated comprehensive microbial community profiles of gull fecal samples using Roche 454 and Illumina MiSeq platforms to investigate the composition and variability of the gull fecal microbial community and to measure the proportion of FIB. Enterococcaceae and Enterobacteriaceae were the two most abundant families in our gull samples. Sequence comparisons between short-read data and nearly full-length 16S rRNA gene clones generated from the same samples revealed Catellicoccus marimammalium as the most numerous taxon among all samples. The identification of bacteria from gull fecal pellets cultured on membrane-Enterococcus indoxyl-?-d-glucoside (mEI) plates showed that the dominant sequences recovered in our sequence libraries did not represent organisms culturable on mEI. Based on 16S rRNA gene sequencing of gull fecal isolates cultured on mEI plates, 98.8% were identified as Enterococcus spp., 1.2% were identified as Streptococcus spp., and none were identified as C. marimammalium. Illumina deep sequencing indicated that gull fecal samples harbor significantly higher proportions of C. marimammalium 16S rRNA gene sequences (>50-fold) relative to typical mEI culturable Enterococcus spp. C. marimammalium therefore can be confidently utilized as a genetic marker to identify gull fecal pollution in the beach environment. PMID:24242244

  11. Analysis of the gull fecal microbial community reveals the dominance of Catellicoccus marimammalium in relation to culturable Enterococci.

    PubMed

    Koskey, Amber M; Fisher, Jenny C; Traudt, Mary F; Newton, Ryan J; McLellan, Sandra L

    2014-01-01

    Gulls are prevalent in beach environments and can be a major source of fecal contamination. Gulls have been shown to harbor a high abundance of fecal indicator bacteria (FIB), such as Escherichia coli and enterococci, which can be readily detected as part of routine beach monitoring. Despite the ubiquitous presence of gull fecal material in beach environments, the associated microbial community is relatively poorly characterized. We generated comprehensive microbial community profiles of gull fecal samples using Roche 454 and Illumina MiSeq platforms to investigate the composition and variability of the gull fecal microbial community and to measure the proportion of FIB. Enterococcaceae and Enterobacteriaceae were the two most abundant families in our gull samples. Sequence comparisons between short-read data and nearly full-length 16S rRNA gene clones generated from the same samples revealed Catellicoccus marimammalium as the most numerous taxon among all samples. The identification of bacteria from gull fecal pellets cultured on membrane-Enterococcus indoxyl-?-D-glucoside (mEI) plates showed that the dominant sequences recovered in our sequence libraries did not represent organisms culturable on mEI. Based on 16S rRNA gene sequencing of gull fecal isolates cultured on mEI plates, 98.8% were identified as Enterococcus spp., 1.2% were identified as Streptococcus spp., and none were identified as C. marimammalium. Illumina deep sequencing indicated that gull fecal samples harbor significantly higher proportions of C. marimammalium 16S rRNA gene sequences (>50-fold) relative to typical mEI culturable Enterococcus spp. C. marimammalium therefore can be confidently utilized as a genetic marker to identify gull fecal pollution in the beach environment. PMID:24242244

  12. First record of Cosmocephalus obvelatus (Acuariidae) in common gulls (Larus canus) from Gangneung, Korea.

    PubMed

    Kim, Se-Min; Park, Bae-Keun; Jung, Bae Dong; Kim, Hyeon-Cheol

    2015-02-01

    A nematode species belonging to the genus Cosmocephalus was collected from the stomach of 2 common gulls, Larus canus. The common gulls were found dead on the seaside of Gangneung City, the Republic of Korea. The worms were identified and classified by light (LM) and scanning electron microscopy (SEM) on the basis of important taxonomic characters. The nematodes were characterized by a body length 9.1-9.3 mm (males) and 15.5-15.9 mm (females) and cordons recurrent in anterior direction and anastomosing laterally at about the level of anterior quarter of the buccal cavity. The salient bicuspid deirids were located on the posterior to the cordons. Lateral alae were well-developed, extending from the level just posterior of deirids to the level about middle of the body. LM and SEM observations identified the worms as C. obvelatus. This is the first reported case of C. obvelatus infection in common gulls in Korea. PMID:25748715

  13. First Record of Cosmocephalus obvelatus (Acuariidae) in Common Gulls (Larus canus) from Gangneung, Korea

    PubMed Central

    Kim, Se-Min; Park, Bae-Keun; Jung, Bae Dong; Kim, Hyeon-Cheol

    2015-01-01

    A nematode species belonging to the genus Cosmocephalus was collected from the stomach of 2 common gulls, Larus canus. The common gulls were found dead on the seaside of Gangneung City, the Republic of Korea. The worms were identified and classified by light (LM) and scanning electron microscopy (SEM) on the basis of important taxonomic characters. The nematodes were characterized by a body length 9.1-9.3 mm (males) and 15.5-15.9 mm (females) and cordons recurrent in anterior direction and anastomosing laterally at about the level of anterior quarter of the buccal cavity. The salient bicuspid deirids were located on the posterior to the cordons. Lateral alae were well-developed, extending from the level just posterior of deirids to the level about middle of the body. LM and SEM observations identified the worms as C. obvelatus. This is the first reported case of C. obvelatus infection in common gulls in Korea. PMID:25748715

  14. Molecular detection of Campylobacter spp. in California gull (Larus californicus) excreta.

    PubMed

    Lu, Jingrang; Ryu, Hodon; Santo Domingo, Jorge W; Griffith, John F; Ashbolt, Nicholas

    2011-07-01

    We examined the prevalence, quantity, and diversity of Campylobacter species in the excreta of 159 California gull (Larus californicus) samples using culture-, PCR-, and quantitative PCR (qPCR)-based detection assays. Campylobacter prevalence and abundance were relatively high in the gull excreta examined; however, C. jejuni and C. lari were detected in fewer than 2% of the isolates and DNA extracts from the fecal samples that tested positive. Moreover, molecular and sequencing data indicated that most L. californicus campylobacters were novel (<97% 16S rRNA gene sequence identity to known Campylobacter species) and not closely related to species commonly associated with human illness. Campylobacter estimates were positively related with those of fecal indicators, including a gull fecal marker based on the Catellicoccus marimammalium 16S rRNA gene. PMID:21622785

  15. Molecular Detection of Campylobacter spp. in California Gull (Larus californicus) Excreta ? †

    PubMed Central

    Lu, Jingrang; Ryu, Hodon; Santo Domingo, Jorge W.; Griffith, John F.; Ashbolt, Nicholas

    2011-01-01

    We examined the prevalence, quantity, and diversity of Campylobacter species in the excreta of 159 California gull (Larus californicus) samples using culture-, PCR-, and quantitative PCR (qPCR)-based detection assays. Campylobacter prevalence and abundance were relatively high in the gull excreta examined; however, C. jejuni and C. lari were detected in fewer than 2% of the isolates and DNA extracts from the fecal samples that tested positive. Moreover, molecular and sequencing data indicated that most L. californicus campylobacters were novel (<97% 16S rRNA gene sequence identity to known Campylobacter species) and not closely related to species commonly associated with human illness. Campylobacter estimates were positively related with those of fecal indicators, including a gull fecal marker based on the Catellicoccus marimammalium 16S rRNA gene. PMID:21622785

  16. Persistent organic pollutants, heavy metals and parasites in the glaucous gull (Larus hyperboreus) on Spitsbergen.

    PubMed

    Sagerup, Kjetil; Savinov, Vladimir; Savinova, Tatiana; Kuklin, Vadim; Muir, Derek C G; Gabrielsen, Geir W

    2009-01-01

    The prediction of a higher parasite infection as a consequence of an impaired immune system with increasing persistent organic pollution (POP) and heavy metal levels were investigated in adult glaucous gull (Larus hyperboreus) from Svalbard. The levels of chlorinated pesticides, polychlorinated biphenyls (PCBs), toxaphenes and polybrominated diphenyl ethers (PBDEs) were measured in liver. Copper, cadmium, lead, mercury, selenium and zinc were measured in kidney samples. An elevated ratio of PCB-118 was found, suggesting that local contamination from the settlement was detectable in the glaucous gull. Eight cestodes, four nematodes, two acanthocephalan and three trematode helminth species were found in the intestine. A positive correlation was found between cestode intensities and selenium levels and between acanthocephalan intensities and mercury levels. No correlation was found between parasite intensities and POP concentrations. It is concluded that the contaminant levels found in glaucous gulls do not cause immune suppression severe enough to affect parasite intensity. PMID:19364623

  17. Validation of water flux and body composition in glaucous gulls (Larus hyperboreus).

    PubMed

    Shaffer, Scott A; Gabrielsen, Geir W; Verreault, Jonathan; Costa, Daniel P

    2006-01-01

    Water influx rates (WIR) measured with tritiated water dilution were compared with direct measures of water and energy intake in glaucous gulls (Larus hyperboreus). Total body water (TBW) measured isotopically was also compared with TBW determined by body composition analysis (BCA) of the same birds. Seventeen wild gulls were captured and studied in outdoor enclosures at Ny-Alesund, Svalbard, in July 2002. Gulls were hand-fed known quantities of Arctic cod (Boreogadus saida) or given water on the basis of one of four experimental treatments: (A) fasting, (B) fish only, (C) water only, or (D) fish and water. Water and energy content of Arctic cod was also determined. WIR of gulls (after subtracting metabolic water production) in treatments A, B, C, and D were 0, 101 +/- 5, 62 +/- 19, and 122 +/- 21 SD g d(-1), respectively. Measured water intake in each group was 0, 111 +/- 2, 64 +/- 3, and 134 +/- 15 SD g d(-1), respectively. On average, WIR underestimated measured water intake in each group. Errors were lowest but most variable for gulls fed water only (-2.2% +/- 32.8%) compared with gulls fed fish only (-9.0% +/- 5.4%) or fish and water (-9.0% +/- 7.0%). Compared with measured water intake, errors in WIR were relatively low overall (-6.9% +/- 17.4%) and comparable to previous validation studies. The difference in TBW determined by BCA versus isotopic dilution ranged between -1.02% and +8.59% of mass. On average, TBW measured isotopically (632 +/- 24 g kg(-1)) overestimated true body water by a factor of 1.033. PMID:16826510

  18. Organohalogen contaminants and reproductive hormones in incubating glaucous gulls (Larus hyperboreus) from the Norwegian Arctic.

    PubMed

    Verreault, Jonathan; Letcher, Robert J; Ropstad, Erik; Dahl, Ellen; Gabrielsen, Geir W

    2006-11-01

    Organohalogen contaminants detected globally in avian wildlife, including populations from the Arctic, have been related to various reproductive hormone potencies, and altered hormonal balance and functions. Besides legacy organochlorine (OC) substances, that is, polychlorinated biphenyls (PCBs) and OC pesticides and by-products, endocrine-disruptive properties have been defined for chemicals of new and emerging environmental concern, such as polybrominated diphenyl ethers (PBDEs) and metabolically derived products like methylsulfonyl (MeSO2)- and hydroxyl (OH)-PCBs. We investigated the relationships between plasma concentrations of selected legacy OCs, PBDEs, and MeSO2- and OH-PCB metabolites and the circulating reproductive hormones testosterone (T), 17beta-estradiol (E2), and progesterone (P4) in incubating male and female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Principal component and regression analyses demonstrated that P4 levels in male glaucous gulls were associated positively with variations of sum (Y) PCB, dichloro-diphenyl-trichloroethane (sigmaDDT), chlordane (sigmaCHL), and sigmaPBDE concentrations, which were the most recalcitrant organohalogens determined in glaucous gulls. No such relationship was found for female glaucous gulls as well as between concentrations of any of the selected organohalogens and levels of T for both sexes. The E2 was not detected in any plasma samples. Present results were highly suggestive that exposure to high organohalogen concentrations in glaucous gulls, particularly the most persistent compound classes, may have the potential to interfere with steroidogenesis and impinge on circulating P4 homeostasis. Because significant effects were found in males exclusively, it cannot be completely ruled out that male glaucous gulls are more sensitive than females to organohalogen-mediated alteration of P4 synthesis and breakdown. PMID:17089723

  19. Changes in prolactin in a highly organohalogen contaminated Arctic top predator seabird, the glaucous gull.

    PubMed

    Verreault, Jonathan; Verboven, Nanette; Gabrielsen, Geir W; Letcher, Robert J; Chastel, Olivier

    2008-05-01

    The factors influencing prolactin (PRL) variation in birds and in wildlife in general have rarely been investigated with respect to the physiological impacts of exposure to environmental contaminants. We investigated the associations between circulating baseline PRL levels and concentrations of eight persistent organohalogen contaminant (OHC) classes (i.e., major organochlorines and brominated flame retardants, and associated metabolic products) in blood (plasma) of free-ranging glaucous gulls (Larus hyperboreus), a top predator in the Norwegian Arctic, engaged in the process of incubation. We further examined whether plasma OHC concentrations were associated with the variation of PRL in glaucous gulls exposed to a standardized capture/restraint protocol. Plasma OHC concentrations in male glaucous gulls were 2- to 3-fold higher relative to females. Baseline PRL levels tended to be higher in females compared to males, although not significantly (p=0.20). In both males and females, the 30-min capture/restraint protocol led on average to a 26% decrease in PRL levels, which resulted in a rate of PRL decrease of 0.76 ng/mL/min. The baseline PRL levels and the rate of decrease in PRL levels tended to vary negatively with plasma OHC concentrations in males, but not in females, although several of these associations did not adhere with the criterion of significance (alpha=0.05). Present results suggest that in highly OHC-exposed male glaucous gulls, the control of PRL release may be affected by the direct or indirect modulating actions of OHCs and/or their metabolically derived products. We conclude that potentially OHC-mediated impact on PRL secretion in glaucous gulls (males) may be a contributing factor to the adverse effects observed on the reproductive behavior, development and population size of glaucous gulls breeding in the Norwegian Arctic. PMID:18374920

  20. Identification of human enteric pathogens in gull feces at Southwestern Lake Michigan bathing beaches.

    PubMed

    Kinzelman, Julie; McLellan, Sandra L; Amick, Ashley; Preedit, Justine; Scopel, Caitlin O; Olapade, Ola; Gradus, Steve; Singh, Ajaib; Sedmak, Gerald

    2008-12-01

    Ring-billed (Larus delawarensis Ord, 1815) and herring (Larus argentatus Pontoppidan, 1763) gulls are predominant species of shorebirds in coastal areas. Gulls contribute to the fecal indicator burden in beach sands, which, once transported to bathing waters, may result in water quality failures. The importance of these contamination sources must not be overlooked when considering the impact of poor bathing water quality on human health. This study examined the occurrence of human enteric pathogens in gull populations at Racine, Wisconsin. For 12 weeks in 2004 and 2005, and 7 weeks in 2006, 724 gull fecal samples were examined for pathogen occurrence on traditional selective media (BBL CHROMagar-Salmonella, Remel Campy-BAP, 7% horse blood agar) or through the use of novel isolation techniques (Campylobacter, EC FP5-funded CAMPYCHECK Project), and confirmed using polymerase chain reaction (PCR) for pathogens commonly harbored in gulls. An additional 226 gull fecal samples, collected in the same 12-week period in 2004, from a beach in Milwaukee, Wisconsin, were evaluated with standard microbiological methods and PCR. Five isolates of Salmonella (0.7%), 162 (22.7%) isolates of Campylobacter, 3 isolates of Aeromonas hydrophila group 2 (0.4%), and 28 isolates of Plesiomonas shigelloides (3.9%) were noted from the Racine beach. No occurrences of Salmonella and 3 isolates of Campylobacter (0.4%) were found at the Milwaukee beach. A subset of the 2004 samples was also examined for Giardia and Cryptosporidium and was found to be negative. Information as to the occurrence of human pathogens in beach ecosystems is essential to design further studies assessing human health risk and to determine the parameters influencing the fate and transport of pathogens in the nearshore environment. PMID:19096455

  1. Comparisons of host specificity in feather louse genera (Insecta: Phthiraptera: Philopteridae) parasitizing gulls (Aves: Laridae: Larus).

    PubMed

    Yamagishi, Ayaka; Yao, Izumi; Johnson, Kevin P; Yoshizawa, Kazunori

    2014-06-01

    Data from gene sequences and morphological structures were collected for the gull feather lice, Saemundssonia lari, Quadraceps punctatus, and Q. ornatus, parasitizing Larus crassirostris and L. schistisagus. Saemundssonia lari was collected from both gull species, and no detectable morphological and genetic differences were found between lice collected from the two different hosts. In contrast, Q. punctatus was only collected from L. crassirostris, whereas Q. ornatus was only collected from L. schistisagus. The two Quadraceps species were genetically highly divergent, and body-size differences corresponding to the gull's body size (Harrison's rule) were also detected between them. Both Quadraceps species were collected from the interbarb of the remex or rectrix, and a match in body size between the louse and the interbarb space may be important in escape from host preening defenses. In contrast, Saemundssonia is a head louse, inhabiting the finer feathers of the head and neck, which the bird cannot preen. A close match to host body size may be less important for lice in the head microhabitat. The differences in the pattern of host-specificity between Saemundssonia and Quadraceps on the two focal host species of this study were probably due to their different microhabitat preferences. More broadly, comparisons of the gene sequences of S. lari and Q. punctatus to those from other gull hosts showed that genetically almost undifferentiated populations of both species were distributed on wide range of gull species. Frequent interspecific hybridization of gulls is one possible factor that may allow these lice to maintain gene flow across multiple host species. PMID:24882099

  2. New organochlorine contaminants and metabolites in plasma and eggs of glaucous gulls (Larus hyperboreus) from the Norwegian Arctic.

    PubMed

    Verreault, Jonathan; Letcher, Robert J; Muir, Derek C G; Chu, Shaogang; Gebbink, Wouter A; Gabrielsen, Geir W

    2005-10-01

    The present study investigated new or lesser-studied and legacy organochlorine (OC) contaminants and metabolites in plasma and eggs of glaucous gulls (Larus hyperboreus) collected from major breeding colonies on Bear Island in the Norwegian Arctic. Hexachlorobutadiene was below the method limit of detection (< 0.07 ng/g lipid wt) in all samples. The sum (sum) of 20 chlorobornane congener concentrations ranged between 294 and 986 ng/g lipid weight and 104 and 1,121 ng/g lipid weight in plasma and eggs, respectively, whereas those of sum 20polychlorinated naphthalene ranged between 1.34 and 126 ng/g lipid weight in plasma and 1.82 and 162 ng/g lipid weight in eggs. Bis(4-chlorophenyl) sulfone concentrations ranged between 5.24 and 143 ng/ g lipid weight plasma, which is the first report of this contaminant in arctic biota north of Sweden. Based on 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs), partial dioxin-like toxicity varied between 3.04 and 20.8 ng TEQ/g lipid weight in plasma and 0.94 and 46.5 ng TEQ/g lipid weight in eggs, and largely was due to concentrations of non-ortho polychlorinated biphenyls (PCBs), with a very minor contribution from mono-ortho PCBs and polychlorinated naphthalenes. The major aryl sulfone metabolite in plasma was an unidentified hexachlorinated MeSO2-PCB congener (range: 13.5-551 ng/g lipid wt), whereas the pentachlorinated congeners 3'- and 4'-MeSO2-CB101 (range: 4.49-38.1 ng/g lipid wt) dominated in eggs. The predominant halogenated phenolic compound (HPC) in plasma was consistently the PCB metabolite 4-OH-CB187 (range: 0.29-17.5 ng/g wet wt), whereas in eggs, detectable HPCs were at very low and transient concentrations. As part of a complex profile of contaminant exposure, these chemical classes and metabolites may be contributing factors to enhance physiological stress in breeding glaucous gulls. PMID:16268150

  3. Dynamics of storage of organochlorine pollutants in herring gulls

    USGS Publications Warehouse

    Anderson, D.W.; Hickey, J.J.

    1976-01-01

    Several organochlorine pollutants were studied over the period of one annual cycle in caged juvenile and wild-collected adult herring gulls (Lagus argentatus) from Lake Michigan. Fish, mostly alewives (Alosa pseudoharengus), comprised the major year-round food items in the wild; alewives were also fed to the caged juveniles. Fish residues averaged around 3 mg/kg of p,p'-DDE, 2 mg/kg p,p'DDT + p,p'-TDE, and 2 mg/kg apparent PCBs. Juvenile body-burdens of DDE and PCBs showed a continual buildup after fledging, then a temporary dynamic equilibrium, related only in part to annual lipid deposition. Maximum body-burdens were reached in both juveniles and adults when winter fat deposits were declining prior to the breeding season?followed by a return to dynamic equilibrium. Residues of DDT and TDE followed closely the annual pattern of lipid deposition in both juveniles and adults. Total body-burdens in both age classes were similar after the buildups to equilibrium in juveniles in their eighth month after fledging. Seasonal variations of residues of DDE and PCBs were characterised by two phases in adults and three in juveniles, which gradually assumed the adult cyclic pattern. The maximum body-burdens attained by caged juveniles fed a diet of Lake Michigan alewives were 290 mg/kg DDE, 19 mg/kg DDT + TDE, and 200 mg/kg apparent PCBs. Residues in wild adults at the same time were 300, 4, and 200 mg/kg of the same residues. Apparent PCBs and DDE were highly accumulative, although DDE levels resulted from dietary DDE, as well as conversion from DDT.

  4. Reduction of garbage in the diet of nonbreeding glaucous gulls corresponding to a change in waste management

    USGS Publications Warehouse

    Weiser, E.L.; Powell, A.N.

    2011-01-01

    Glaucous gulls (Larus hyperboreus) are major predators in the Arctic and may benefit from human development. We studied use of garbage by glaucous gulls in Barrow, Alaska, in 2007, when municipal waste was disposed of in a landfill, and in 2008, when it was incinerated. In both years, diet samples from breeding adult gulls contained less garbage than those from loafing nonbreeding gulls (mostly subadults of less than four years), possibly because the breeding colony was more distant than many loafing sites from the landfills. Although breeding gull samples showed no change, garbage in regurgitated pellets and food remains of nonbreeding gulls was significantly less prevalent in 2008 than in 2007 (28% vs. 43% occurrence in diet samples), and this reduction could be explained by the switch from landfill to waste incineration. Yet garbage remained a substantial part of nonbreeding gull diet after the management change. Other aspects of waste management, such as storage prior to disposal, may also be important in limiting scavengers' access to garbage and thus reducing the indirect impact of human development on prey species of conservation concern. ?? The Arctic Institute of North America.

  5. Relationship between the contamination of gulls (Larus dominicanus) and oysters (Crassostrea gigas) with Salmonella serovar Typhimurium by PCR-RFLP.

    PubMed

    Albarnaz, Jonas D; Toso, Javier; Corrêa, Adriana A; Simões, Cláudia M O; Barardi, Célia R M

    2007-04-01

    Shellfish can bioaccumulate in their tissues pathogenic contaminants present in water and they have been related with several outbreaks of food-borne diseases worldwide. With their increased population in urban areas, gulls have been reported as an important source of water environment contamination. During a 10-month period, water, gulls feces and oyster samples were collected in a shellfish harvesting site and analyzed for total and fecal coliform counts (water) and Salmonella presence (gull feces and oyster meat). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to differentiate Salmonella species detected in gulls and oysters. Salmonella presence was detected in 3/10 of oyster samples and in 6/10 of gull feces samples by PCR. There was a relationship between Salmonella presence in oysters and fecal contamination in water. Restriction profiles of both gulls and oyster samples were similar to Salmonella Typhimurium profile by RFLP. These findings indicate strong evidence that gulls can contribute to Salmonella contamination of harvested oysters. PMID:17616869

  6. Mutagenicity studies on herring gulls from different locations on the Great Lakes. I. Sister chromatid exchange rates in herring-gull embryos.

    PubMed

    Ellenton, J A; McPherson, M F

    1983-01-01

    Unincubated herring-gull (Larus argentatus) eggs were collected from five colonies on the Great Lakes Basin and from one relatively pollutant-clean colony on the Atlantic coast. Eggs were incubated at 38 degrees C with 55% relative humidity, and sister chromatid exchange (SCE) levels were measured in 7-d embryos. For all of the colonies, the average SCE/chromosome frequency ranged from 0.069 to 0.101; however, no significant differences were found. Organochlorine analysis was carried out on egg homogenates for each colony, to determine the levels of several contaminants. There were no relationships found between any of the contaminant levels and the SCE frequencies. The study indicates that either the contaminants present in the herring-gull eggs are not having any genetic effects on the embryos or, alternatively, that there may be genetic damage that measurement of SCEs in the 7-d embryo is unable to detect. PMID:6655738

  7. Diurnal trends in the mid-water biomass community of the Northwestern Hawaiian Islands observed acoustically

    NASA Astrophysics Data System (ADS)

    Lammers, Marc O.; Brainard, Russell E.; Au, Whitlow W. L.

    2004-10-01

    The nighttime mid-water biomass occurring near six banks in the Northwestern Hawaiian Islands was investigated using 38- and 120-kHz EK60 echosounders. Locations investigated included: French Frigate Shoals, Maro Reef, Lisianksi Island/Neva Shoals, Pearl and Hermes Atoll, Kure Atoll and Midway Atoll. Surveys were designed to sample transect lines parallel and normal to shore between 10 p.m. and 7 a.m. and once during daylight hours. A diurnal trend was found in the occurrence of mid-water sound scattering organisms at all six locations. Communities of organisms accumulate at night on the edges of each island between the 20- and 100-fathom isobaths. The highest densities of organisms restrict their horizontal movements to depths of 20 fathoms or deeper, but increases in biomass were also observed at shallower depths. The northern islands of Kure, Midway, and Pearl and Hermes Atolls exhibited patchier distributions than the southern islands. The composition of the biomass is presently unclear but resembles the mesopelagic boundary community found near the Main Hawaiian Islands. Simultaneous observations with the TOAD camera system revealed clouds of zooplankton mixed with small fish and other micronekton. The nightly influx of these organisms is likely a significant, though poorly understood, component of these islands ecosystems.

  8. Aspects of the biology of the common gull larus canus from remains left by predators

    Microsoft Academic Search

    J. C. A. Craik

    1997-01-01

    A sample of 224 adult Common Gulls from west Scotland was used to obtain biometric and moult data. 222 of these were dead; about 50% had been killed by North American Mink and 39% by raptors, usually Peregrines. In 71 males and 65 females the sex was identified by inspection of the gonads; these birds were used to show significant

  9. Long-Term Studies of Common Gulls (Larus Canus) in Estonia: Responses to Environmental Conditions

    Microsoft Academic Search

    Kalev Rattiste; Urmas Tartes

    2005-01-01

    The population of Common Gulls has been studied since 1962, making the analysis of longterm changes in the population and the impact of the changing environment possible. Due to the fixed clutch size, the reproductive lifespan and survival of offspring from hatching to maturity, both affected mainly by winter severity, are the prime creators of the variation in lifetime reproductive

  10. The relationship between parental age and reproductive effort in the California Gull ( Larus californicus )

    Microsoft Academic Search

    Bruce H. Pugesek

    1983-01-01

    Reproductive effort was compared among California gulls ranging in age from 3 to 18 years old. Results indicated that reproductive effort increased with parental age. Older parents (11–18 years old) invested more in foraging effort and in defense of offspring than did younger parents (<10 years old), and did so over a greater period of time. Increases with age in

  11. California gull chicks raised near colony edges have elevated stress levels

    Microsoft Academic Search

    Garth Herring; Joshua T. Ackerman

    2011-01-01

    Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine

  12. Determinants of local recruitment in a growing colony of Audouin's gull

    Microsoft Academic Search

    Daniel Oro; Roger Pradel

    2000-01-01

    Summary 1. Local recruitment of Audouin's gull (Larus audouinii Payraudeau) was studied between 1988 and 1997 at the Ebro Delta colony (north-western Mediterranean). Since its establishment in 1981, the colony has dramatically grown to include, in 1997, 65% of the total world population. Several hypotheses were tested, involving the eÄects of a badger predatory event in 1994, and sex, age

  13. Age-specific survivorship in relation to clutch size and fledging success in California gulls

    Microsoft Academic Search

    Bruce H. Pugesek

    1987-01-01

    Data from a natural population of California gulls (Larus californicus) demonstrated that increasing reproductive effort with age was associated with reduced survivorship. Number of offspring fledged but not clutch size was inversely related to adult survivorhip indicating that reproductively induced mortality resulted from the cumulative effects of the entire breeding season. Agerelated increases in fledging success were correlated with increased

  14. Parental effort in the California gull: tests of parent-offspring conflict theory

    Microsoft Academic Search

    Bruce H. Pugesek

    1990-01-01

    Parental effort was studied among knownaged California gulls (Larus californicus) with a brood size of two. Results supported three of Triver's predictions from parent-offspring conflict theory. First, the amount of time parents withheld food from offspring increased with increasing offspring age. Second, older parents were less likely than younger parents to withhold food from offspring throughout the period of parental

  15. Increased Reproductive Effort with Age in the California Gull (Larus californicus).

    PubMed

    Pugesek, B H

    1981-05-15

    Comparisons of reproductive behaviors of three age classes of California gulls demonstrate that reproductive effort increases with age in this seabird. These findings contradict the assumption that increased reproductive success with age results from increased experience and social status and demonstrate that selection for increased reproductive effort can occur in long-lived species. PMID:17752279

  16. Increased Reproductive Effort with Age in the California Gull (Larus californicus)

    Microsoft Academic Search

    Bruce H. Pugesek

    1981-01-01

    Comparisons of reproductive behaviors of three age classes of California gulls demonstrate that reproductive effort increases with age in this seabird. These findings contradict the assumption that increased reproductive success with age results from increased experience and social status and demonstrate that selection for increased reproductive effort can occur in long-lived species.

  17. Offspring growth in the California gull: reproductive effort and parental experience hypotheses

    Microsoft Academic Search

    Bruce H. Pugesek

    1995-01-01

    Measures of adult feeding and foraging behaviour in the California gull, Larus californicus, were related to the growth of their offspring. Offspring showed significantly higher growth when average feeding interval, a measure of the time interval between feedings, and feeding latency following foraging decreased. The amount of time parents foraged was positively related to offspring growth and negatively correlated with

  18. Shell conductance, daily water loss, and water content of Andean gull and Puna ibis eggs.

    PubMed

    Carey, C; Leon-Velarde, F; Castro, G; Monge, C

    1987-01-01

    Characteristics of Andean gull (Larus serranus) and Puna ibis (Plegadis ridgwayi) eggs laid at 4,400 m in the Peruvian Andes were studied to determine how the conflicting requirements of maximizing O2 availability to the embryo while minimizing excessive losses of water vapor and CO2 have been met by avian populations breeding at high altitudes. Egg masses, linear dimensions, and surface areas of these montane eggs were similar to those of Heermann's gull (Larus heermanni) and glossy ibises (Plegadis falcinellus), but conductance to water vapor (GH2O, standardized to 760 torr) of Andean gull and Puna ibis eggs averaged 74.5% and 68.4%, respectively, of lowland values. The difference in GH2O of Andean gull eggs was caused primarily by a reduction in the number of pores per egg; both an increased shell thickness and a smaller number of pores reduced GH2O of Puna ibis eggs. Since the reduction of GH2O of montane eggs did not fully compensate for the change in barometric pressure (59% of sea level) and the increase in gaseous diffusion coefficients at 4,400 m, the "effective" conductance of the eggs at that altitude was greater than at sea level. Therefore, the eggs lost substantially more water during incubation than did lowland eggs. The modifications in eggshell characteristics of montane eggs may have resulted from selection to increase O2 availability to the embryo. PMID:3598496

  19. Persistent organic pollutants, heavy metals and parasites in the glaucous gull ( Larus hyperboreus) on Spitsbergen

    Microsoft Academic Search

    Kjetil Sagerup; Vladimir Savinov; Tatiana Savinova; Vadim Kuklin; Derek C. G. Muir; Geir W. Gabrielsen

    2009-01-01

    The prediction of a higher parasite infection as a consequence of an impaired immune system with increasing persistent organic pollution (POP) and heavy metal levels were investigated in adult glaucous gull (Larus hyperboreus) from Svalbard. The levels of chlorinated pesticides, polychlorinated biphenyls (PCBs), toxaphenes and polybrominated diphenyl ethers (PBDEs) were measured in liver. Cupper, cadmium, lead, mercury, selenium and zinc

  20. Relationships between ecological variables and four organochlorine pollutants in an artic glaucous gull ( Larus hyperboreus) population

    Microsoft Academic Search

    Jan Ove Bustnes; Øystein Miland; Magnus Fjeld; Kjell Einar Erikstad; Janneche Utne Skaare

    2005-01-01

    The Arctic has become a sink for organochlorine contaminants (OCs) from lower latitudes, and relatively high levels have been found in different biota. Recent studies of the glaucous gull, Larus hyperboreus, a top predator in the arctic food web, have documented that high blood residues of various OCs are related to lower reproductive performance and reduced adult survival. Here we

  1. Persistent organic pollutants and mercury in dead and dying glaucous gulls ( Larus hyperboreus) at Bjørnøya (Svalbard)

    Microsoft Academic Search

    Kjetil Sagerup; Lisa B. Helgason; Anuschka Polder; Hallvard Strøm; Terje D. Josefsen; Janneche U. Skåre; Geir W. Gabrielsen

    2009-01-01

    Dead and dying glaucous gulls (Larus hyperboreus) were collected on Bjørnøya in the Barents Sea in 2003, 2004 and 2005. Autopsies of the seabirds only explained a clear cause of death for three (14%) of the 21 birds. A total of 71% of the birds were emaciated. Liver and brain samples were analysed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs),

  2. Chlorinated hydrocarbons in glaucous gulls ( Larus hyperboreus) in the southern part of Svalbard

    Microsoft Academic Search

    Geir Wing Gabrielsen; Janneche Utne Skaare; Anuschka Polder; Vidar Bakken

    1995-01-01

    In 1989, a number of glaucous gulls (Larus hyperboreus) were found dead near a seabird cliff at south Svalbard. In an effort to clucidate the course of death, 12 individuals were sent to the Central Veterinary Institute for autopsy and analysis of chlorinated pesticides and polychlorinated biphenyls (PCBs) in samples of liver, kidney, brain and muscle. Eggs of common and

  3. Persistent organic pollutants and mercury in dead and dying glaucous gulls

    Microsoft Academic Search

    Kjetil Sagerup; Lisa B. Helgason; Anuschka Polder; Hallvard Strøm; Janneche U. Skåre; Geir W. Gabrielsen

    Abstract Dead and dying glaucous gulls (Larus hyperboreus) were collected on Bjørnøya in the Barents Sea in 2003, 2004 and 2005. Autopsies ofthe seabirds only explained a clear death cause for three (14%) of the 21 birds. A total of 71% of the birds were emaciated. Liver and brain samples were analysed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated

  4. 78 FR 46410 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel TWO BUOYS ONE GULL...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ...1200 New Jersey Avenue SE., Washington, DC 20590. You may also...Avenue SE., Room W23-453, Washington, DC 20590. Telephone 202-366-0903...of the vessel TWO BUOYS ONE GULL is: Intended Commercial Use...California, Oregon, and Washington.'' The complete...

  5. Water balance dynamics of a boreal forest watershed: White Gull Creek basin, 1994–1996

    Microsoft Academic Search

    Bart Nijssen; Dennis P. Lettenmaier

    2002-01-01

    Field measurements from the Boreal Ecosystem-Atmosphere Study (BOREAS) were combined to calculate the water balance of the White Gull Creek basin for the three year period 1994–1996. Evapotranspiration was mapped from the observations made at the BOREAS flux towers to the basin using a simple evaporation model with a bulk canopy resistance based on tower observations. Runoff ratios were low,

  6. Water balance dynamics of a boreal forest watershed: White Gull Creek basin, 1994-1996

    Microsoft Academic Search

    Bart Nijssen; Dennis P. Lettenmaier

    2002-01-01

    Field measurements from the Boreal Ecosystem-Atmosphere Study (BOREAS) were combined to calculate the water balance of the White Gull Creek basin for the three year period 1994-1996. Evapotranspiration was mapped from the observations made at the BOREAS flux towers to the basin using a simple evaporation model with a bulk canopy resistance based on tower observations. Runoff ratios were low,

  7. A Communicative Analysis of Chekhovian Drama as Portrayed in "The Sea Gull."

    ERIC Educational Resources Information Center

    Hellweg, John D.; Hellweg, Susan A.

    The precision and poetic logic of the language used by Anton Chekhov in his plays, particularly "The Sea Gull," can be explored through an analysis of his use of dialogue, characterization, and imagery. Measuring the nature of a relationship, rather than providing a direct literal interchange, the dialogue is both social, when individual…

  8. Interpreting temporal trends in Great Lakes organochlorine levels: Results from the herring gull surveillance program

    SciTech Connect

    Hebert, C.E.; Shutt, J.L.; Norstrom, R.J. [Canadian Wildlife Service, Hull, Quebec (Canada). National Wildlife Research Centre; Weseloh, D.V. [Canadian Wildlife Service, Burlington, Ontario (Canada)

    1995-12-31

    The Canadian Wildlife Service`s herring gull (Larus argentatus) surveillance program has demonstrated the utility of this species as a monitor of spatial and temporal trends in Great Lakes contaminant levels. Organochlorine concentrations in herring gull eggs decreased significantly in the 1970s and early 1980s as a result of control measures. Since the mid-1980s, however, concentrations of many compounds have been relatively constant. In addition, periodic fluctuations in egg contaminant concentrations hamper the ability to interpret more recent temporal trends in organochlorine levels. To evaluate the progress towards achieving the virtual elimination of organochlorines from the Great Lakes the authors must improve their understanding of the factors which regulate organochlorine bioaccumulation. This is particularly important for those species which have been selected as key indicators of ecosystem contamination, such as the herring gull. The goal of this paper is to examine some of the factors which may be responsible for the temporal fluctuations in herring gull egg contaminant concentrations. The regulation of contaminant bioavailability and transfer by changes in weather patterns and food web dynamics will be examined.

  9. Changes in food web structure affect rate of PCB decline in herring gull (Larus argentatus) eggs

    SciTech Connect

    Hebert, C.E.; Hobson, K.A.; Shutt, J.L.

    2000-05-01

    Biological monitors provide important information regarding temporal trends in levels of persistent organic pollutants. Correct interpretation of these trends is critical if one is to accurately assess his progress in eliminating these contaminants from the environment. In the Laurentian Great Lakes, polychlorinated biphenyl concentrations in herring gull eggs declined during the 1970s and early 1980s. By the mid-1980s, further declines were not as obvious. An exception to this trend was observed in eggs from Lake Erie. On that lake, egg PCB concentrations continued to decline rapidly during the 1980s/1990s. Evidence from stable isotope analysis indicated that temporal changes in the composition of the herring gull diet occurred on Lake Erie. In the eastern basin, declines in fish availability may have forced the gulls to incorporate a greater proportion of terrestrial food into their diets. Decreases in the proportion of fish in the gull diet would have resulted in reduced PCB exposure. This may be partially responsible for the continuing rapid rate of decline in egg PCB concentrations. This decline should be interpreted with caution. These trends may not be indicative of lake-wide declines in PCB bioavailability but only reflect changes in dietary exposure brought about by alterations in food web structure.

  10. RECRUITMENT AT A BLACK-BILLED GULL COLONY: IMPLICATIONS FOR THE INFORMATION CENTER HYPOTHESIS

    Microsoft Academic Search

    ROGER M. EVANS

    The extent to which a flock leader advertises its departure from a colony and recruits flock mates is an important issue of the Information Center hypothesis. At a colony of Black-billed Gulls (Larus bulleri), I found that attractive calls were given by some leaders, that leaders called more often than followers, and that calling leaders recruited followers more often than

  11. Corrective Action Investigation Plan for Corrective Action Unit 447: Project Shoal Area, Nevada Subsurface Site

    SciTech Connect

    DOE/NV

    1998-11-01

    This Corrective Action Investigation Plan (CAIP) describes the US Department of Energy's (DOE's) continued environmental investigation of the subsurface Project Shoal Area (PSA) Corrective Action Unit (CAU) 447. The PSA is located in the Sand Springs Mountains in Churchill County, Nevada, about 48 kilometers (km) (30 miles [mi]) southeast of Fallon, Nevada. Project Shoal was part of the Vela Uniform Program which was conducted to improve the US' ability to detect, identify, and locate underground nuclear detonations. The test consisted of detonating a 12-kiloton nuclear device deep underground in granitic rock to determine whether seismic waves produced by an underground nuclear test could be differentiated from seismic waves produced by a naturally occurring earthquake. The test was a joint effort conducted by the US Atomic Energy Commission (AEC) and the US Department of Defense (DoD) in October 1963 (AEC, 1964).

  12. Comparing wave shoaling methods used in large-scale coastal evolution modeling

    NASA Astrophysics Data System (ADS)

    Limber, P. W.; Adams, P. N.; Murray, A.

    2013-12-01

    A variety of methods are available to simulate wave propagation from the deep ocean to the surf zone. They range from simple and computationally fast (e.g. linear wave theory applied to shore-parallel bathymetric contours) to complicated and computationally intense (e.g., Delft's ';Simulating WAves Nearshore', or SWAN, model applied to complex bathymetry). Despite their differences, the goal of each method is the same with respect to coastline evolution modeling: to link offshore waves with rates of (and gradients in) alongshore sediment transport. Choosing a shoaling technique for modeling coastline evolution should be partly informed by the spatial and temporal scales of the model, as well as the model's intent (is it simulating a specific coastline, or exploring generic coastline dynamics?). However, the particular advantages and disadvantages of each technique, and how the advantages/disadvantages vary over different model spatial and temporal scales, are not always clear. We present a wave shoaling model that simultaneously computes breaking wave heights and angles using three increasingly complex wave shoaling routines: the most basic approach assuming shore-parallel bathymetric contours, a wave ray tracing method that includes wave energy convergence and divergence and non-shore-parallel contours, and a spectral wave model (SWAN). Initial results show reasonable agreement between wave models along a flat shoreline for small (1 m) wave heights, low wave angles (0 to 10 degrees), and simple bathymetry. But, as wave heights and angles increase, bathymetry becomes more variable, and the shoreline shape becomes sinuous, the model results begin to diverge. This causes different gradients in alongshore sediment transport between model runs employing different shoaling techniques and, therefore, different coastline behavior. Because SWAN does not approximate wave breaking (which drives alongshore sediment transport) we use a routine to extract grid cells from SWAN output where wave height is approximately one-half of the water depth (a standard wave breaking threshold). The goal of this modeling exercise is to understand under what conditions a simple wave model is sufficient for simulating coastline evolution, and when using a more complex shoaling routine can optimize a coastline model. The Coastline Evolution Model (CEM; Ashton and Murray, 2006) is used to show how different shoaling routines affect modeled coastline behavior. The CEM currently includes the most basic wave shoaling approach to simulate cape and spit formation. We will instead couple it to SWAN, using the insight from the comprehensive wave model (above) to guide its application. This will allow waves transformed over complex bathymetry, such as cape-associated shoals and ridges, to be input for the CEM so that large-scale coastline behavior can be addressed in less idealized environments. Ashton, A., and Murray, A.B., 2006, High-angle wave instability and emergent shoreline shapes: 1. Modeling of sand waves, flying spits, and capes: Journal of Geophysical Research, v. 111, p. F04011, doi:10.1029/2005JF000422.

  13. Wave spectra of a shoaling wave field: A comparison of experimental and simulated results

    NASA Technical Reports Server (NTRS)

    Morris, W. D.; Grosch, C. E.; Poole, L. R.

    1982-01-01

    Wave profile measurements made from an aircraft crossing the North Carolina continental shelf after passage of Tropical Storm Amy in 1975 are used to compute a series of wave energy spectra for comparison with simulated spectra. Results indicate that the observed wave field experiences refraction and shoaling effects causing statistically significant changes in the spectral density levels. A modeling technique is used to simulate the spectral density levels. Total energy levels of the simulated spectra are within 20 percent of those of the observed wave field. The results represent a successful attempt to theoretically simulate, at oceanic scales, the decay of a wave field which contains significant wave energies from deepwater through shoaling conditions.

  14. Patterns of coral recruitment at the Gneering Shoals, southeast Queensland, Australia

    Microsoft Academic Search

    S. A. Banks; V. J. Harriott

    1996-01-01

    Recruitment patterns of scleractinian corals were investigated at the Gneering Shoals, a coral-dominated rocky-reef south of the Great Barrier Reef, in subtropical Queensland. The density of recruits (mean of 0.8 to 6.3 recruits per tile (15 cm × 15 cm) pair from 4 sites) was the lowest ever recorded from six regions in tropical or subtropical eastern Australia that have

  15. Accuracy of bathymetry and current retrievals from airborne optical time-series imaging of shoaling waves

    Microsoft Academic Search

    Cynthia C. Piotrowski; John P. Dugan

    2002-01-01

    A sequence of visual images of shoaling ocean waves collected from an aircraft can be used to retrieve maps of water depth and\\/or currents. The data are mapped to rectilinear coordinates on the mean ocean surface, and three-dimensional (3D) cubes of these data (typically 2-min dwell and 256 m × 256 m square area) are Fourier transformed to provide the

  16. Significance of carbonate-clastic shoaling cycles in Mississippian of northern Arkansas

    SciTech Connect

    Downs, J.W.

    1983-03-01

    Shoaling-upward carbonate shelf cycles are known to occur in many parts of the world and throughout the geologic record. Upper Mississippian (Chesterian) strata in northern Arkansas consist of alternating limestones and shales that include a set of shoaling-upward cycles. These cycles, occurring within the dominantly carbonate Pitkin Formation, differ from the pattern described above in that they contain a significant terrigenous component. At the beginning of a cycle, the shoreline was distinct from the deeply submerged shelf and lime and terrigenous mud accumulated in a quiet-water setting. Thickness and facies analysis of the Pitkin indicate an east-west trending shelf with a shoreline located in southern Missouri, perhaps curving south around the Ozark uplift. Eastward increase in shale percentage in the Pitkin suggests transport of fine clastics around the southeast flank of this uplift. The Illinois basin was an active Chesterian depocenter and during periods of maximum transgression fine clastics may have passed through a seaway southwest into northern Arkansas. As shoaling proceeded, the shoreline regressed south with the advancing carbonate sand sheet, cutting off the avenue of fine clastics. Quartz sand, probably derived from a thick sequence of lower Paleozoic sandstones exposed along the uplift by the retreating sea, became admixed with oolite across the newly built platform. These shoaling cycles are the product of slow, steady, subsidence along a northern Arkansas shelf punctuated by episodes of relatively rapid carbonate sand sedimentation and clastic influx. A similar tectonic and depositional setting must have given rise to other such deposits that occur in the geologic record.

  17. Keep the chicks moving: how Sandwich terns can minimize kleptoparasitism by black-headed gulls.

    PubMed

    Stienen; Brenninkmeijer

    1999-05-01

    Sandwich terns, Sterna sandvicensis, often nest in association with black-headed gulls, Larus ridibundus. The gulls provide protection against predators, but can also adversely affect the terns' reproductive success through predation and piracy of fish. To test whether leading the chicks away from the nest site is an evasive strategy used by the parents to reduce the incidence of robbery by the gulls, we kept one group of Sandwich tern chicks at their original breeding site, while, with a wire-netting enclosure, we moved another group away from the gulls. The rate of kleptoparasitism was greatly reduced when the tern chicks were moved away from the original nest site, resulting in faster growth and earlier fledging. The rate of food parasitism and chick condition were affected only during the first 5 days of the experiment. After that, the rate of kleptoparasitism no longer differed between chicks that we moved away and those remaining in the colony. A second shift of the chicks again led to less kleptoparasitism and better chick condition. In line with these findings, the condition of free-living chicks that were lured away from their nesting site by their parents also improved. In particular, chicks initially in poor condition, which apparently suffered from high rates of kleptoparasitism, left the colony site. Free-living chicks are often lured away from the robbing gulls. However, not all subcolonies provided suitable escape routes and subsequently chicks in such subcolonies suffered from high mortality rates. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10328801

  18. Distribution patterns predict individual specialization in the diet of dolphin gulls.

    PubMed

    Masello, Juan F; Wikelski, Martin; Voigt, Christian C; Quillfeldt, Petra

    2013-01-01

    Many animals show some degree of individual specialization in foraging strategies and diet. This has profound ecological and evolutionary implications. For example, populations containing diverse individual foraging strategies will respond in different ways to changes in the environment, thus affecting the capacity of the populations to adapt to environmental changes and to diversify. However, patterns of individual specialization have been examined in few species. Likewise it is usually unknown whether specialization is maintained over time, because examining the temporal scale at which specialization occurs can prove difficult in the field. In the present study, we analyzed individual specialization in foraging in Dolphin Gulls Leucophaeus scoresbii, a scavenger endemic to the southernmost coasts of South America. We used GPS position logging and stable isotope analyses (SIA) to investigate individual specialization in feeding strategies and their persistence over time. The analysis of GPS data indicated two major foraging strategies in Dolphin Gulls from New I. (Falkland Is./Islas Malvinas). Tagged individuals repeatedly attended either a site with mussel beds or seabird and seal colonies during 5 to 7 days of tracking. Females foraging at mussel beds were heavier than those foraging at seabird colonies. Nitrogen isotope ratios (?(15)N) of Dolphin Gull blood cells clustered in two groups, showing that individuals were consistent in their preferred foraging strategies over a period of at least several weeks. The results of the SIA as well as the foraging patterns recorded revealed a high degree of specialization for particular feeding sites and diets by individual Dolphin Gulls. Individual differences in foraging behavior were not related to sex. Specialization in Dolphin Gulls may be favored by the advantages of learning and memorizing optimal feeding locations and behaviors. Specialized individuals may reduce search and handling time and thus, optimize their energy gain and/or minimize time spent foraging. PMID:23844073

  19. Living on the Edge: Demography of the Slender-Billed Gull in the Western Mediterranean

    PubMed Central

    Sanz-Aguilar, Ana; Tavecchia, Giacomo; Afán, Isabel; Ramírez, Francisco; Doxa, Aggeliki; Bertolero, Albert; Gutiérrez-Expósito, Carlos; Forero, Manuela G.; Oro, Daniel

    2014-01-01

    Small and peripheral populations are typically vulnerable to local extinction processes but important for the metapopulation dynamics of species. The Slender-billed gull (Chroicocephalus genei) is a long-lived species breeding in unstable ephemeral coastal habitats. Their Western Mediterranean populations are relatively small and represent the edge of their global geographical distribution. At a local scale, using long-term data (14 years) on annual breeding success and capture-resights of marked individuals, we estimated and compared the vital rates and evaluated the connectivity of two Spanish populations (Ebro Delta and Doñana) varying in their local environmental conditions. At a metapopulation scale, we analyzed 22 years of data on breeding numbers to predict their future prospects by means of population demographic models. Local survival and breeding success of gulls from the Ebro Delta was lower than those from Doñana, which is likely the result of higher permanent emigration and/or winter mortality in the former. Gulls from the Ebro Delta wintered mostly in Mediterranean areas whereas those from Doñana did so in Atlantic coasts, where food availability is higher. Whereas adult local survival was constant, juvenile local survival showed temporal parallel variations between colonies, probably related to natal dispersal to other breeding colonies. Our results suggested that dispersal was higher at the Ebro Delta and gulls emigrating from their natal colonies settled preferentially in close patches. We found large fluctuations in breeding numbers among local populations probably related to the fact that the Slender-billed gull is a species adapted to unstable and unpredictable habitats with high abilities to disperse between suitable patches depending on environmental stochastic conditions during breeding. PMID:24664115

  20. Consequences of shoaling of the Central American Seaway determined from modeling Nd isotopes

    NASA Astrophysics Data System (ADS)

    Sepulchre, P.; Arsouze, T.; Donnadieu, Y.; Dutay, J.-C.; Jaramillo, C.; Le Bras, J.; Martin, E.; Montes, C.; Waite, A. J.

    2014-03-01

    The Central American Seaway played a pivotal role in shaping global climate throughout the late Cenozoic. Recent geological surveys have provided new constraints on timing of the seaway shoaling, while neodymium isotopic (?Nd) data measured on fossil teeth, debris, and ferromanganese crusts have helped define the history of water masses in the region. Here we provide the first 3-D simulations of ?Nd responses to the shoaling seaway. Our model suggests that a narrow and shallow seaway is sufficient to affect interoceanic circulation, that inflow/outflow balance between the Caribbean and the Antilles responds nonlinearly to sill depth, and that a seaway narrower than 400 km is consistent with an active Atlantic meridional overturning circulation during the late Miocene. Simulated ?Nd values in the Caribbean confirm that inputs from radiogenic Pacific waters in the Caribbean decrease as the seaway shoals. Despite model limitations, a comparison between our results and ?Nd values recorded in the Caribbean helps constrain the depth of the Central American Seaway through time, and we infer that a depth between 50 and 200 m could have been reached 10 Ma ago.

  1. Evaluation of dredged material proposed for ocean Disposal from Shoal Harbor/Compton Creek Project Area

    SciTech Connect

    Gardiner, W.W.; Borde, A.B.; Nieukirk, S.L.; Barrows, E.S.; Gruendell, B.D.; Word, J.Q.

    1996-10-01

    The objective of the Shoal Harbor/Compton Creek Project was to evaluate proposed dredged material from the Shoal harbor/Compton Creek Project Area in Belford and Monmouth, New Jersey to determine its suitability for unconfined ocean disposal at the Mud Dump Site. This was one of five waterways that the US Army Corps of Engineers- New York District requested the Battelle Marine Sciences Laboratory (MSL) to sample and evaluate for dredging and disposal in May 1995. The evaluation of proposed dredged material from the Shoal Harbor/Compton Creek Project area consisted of bulk chemical analyses, chemical analyses of dredging site water and elutriate, benthic and water-column acute toxicity tests and bioaccumulation studies. Eleven core samples were analyzed or grain size, moisture content, and total organic carbon. Other sediments were evaluated for bulk density, specific gravity, metals, chlorinated pesticides, polychlorinated biphenyl (PCB) congers, polynuclear aromatic hydrocarbons, and 1,4- dichlorobenzene. Dredging site water and elutriate water were analyzed for metals, pesticides, and PCBs.

  2. Continuous wide area monitoring of fish shoaling behavior with acoustic waveguide sensing and bioclutter implications

    NASA Astrophysics Data System (ADS)

    Makris, Nicholas C.; Ratilal, Purnima; Symonds, Deanelle T.; Nero, Redwood W.

    2001-05-01

    Field measurements are used to show that the detailed behavior of fish shoals can be continuously monitored at roughly 1-min intervals over wide areas spanning hundreds of square kilometers by long range acoustic waveguide sensing. The technique was used on the New Jersey Continental Shelf to produce unprecedented video images of shoal formation, fragmentation, and migration. Simultaneous line-transect measurements show the imaged shoals to contain pelagic fish with densities of at least one individual per meter3. The technique relies upon acoustic waveguide propagation in the continental shelf. Here, trapped modes dominate propagation and suffer only cylindrical spreading loss rather than the spherical loss suffered in free-space transmission or short-range propagation in the ocean. In contrast, standard methods for fish surveyance involve line transect measurements from slow moving research vessels that significantly under-sample fish distributions in time and space, leaving an incomplete behavioral picture. The implications of this bioclutter phenomenon on the Navy's long range active sonar operations in continental shelf environments are discussed.

  3. Island Biogeography

    NSDL National Science Digital Library

    John Jungck (BioQUEST Curriculum Consortium; Biology)

    2005-12-16

    This excel workbook demonstrates the principles of the MacArthur-Wilson theory of Island Biogeography. It allows the user to define the mainland species pool, area of the island, and distance of the island from the mainland. Graphical output included species richness equilibrium at varying island size and distance. The workbook also allows the user to calculate a species-area function for data entered into the data input page. Several datasets on island area and species richness are included for various types of islands and species. Variables and formulas are defined in the accompanying tutorial.

  4. Developing a statistical model for locating bedrock shoal habitat to aid in understanding naturally occurring denitrification processes in a mid-sized river

    NASA Astrophysics Data System (ADS)

    Davis, L.; Bishop, J. A.

    2013-12-01

    This research presents results from an ongoing study of denitrification in bedrock shoals of the Cahaba River of Alabama. Previous research suggests that plant macrophytes and their associated microbial communities located in bedrock shoals help reduce DIN concentrations by 50% in the Cahaba River. As a first step in creating a geo-ecological model capable of predicting the location of denitrification 'hotspots,' we have developed a statistical model capable of predicting the location of bedrock shoals. We characterized rock integrity (GSI - Geological Strength Index), streamflow relative to bedrock orientation (perpendicularity index), and channel confinement (channel width/valley width) at shoaled (n=100) and non-shoaled (n=70) sections of the Cahaba River using aerial photography, field data, and geologic maps in a GIS environment. We used these data to develop a binary logistic regression model, which suggested that the two most significant variables for predicting shoal occurrence were rock integrity (p=.000) and perpendicularity index (p=.001). The model correctly predicted whether a location was shoaled or not 92% of the time. When used to predict the status of non-studied sites (i.e., not a part of the model's derivation) the model performed reliably, giving all shoaled locations > 90% probability of being shoaled and assigning < 35% probability of being shoaled to all non-shoaled sites. Though only a first-step in a long process, these results are crucial to creating a geo-ecological model to identify denitrification 'hotspots,' as bedrock-shoals provide a spatially explicit feature through which spatial variability of plant macrophytes and their associated microbial communities can be modeled at a variety of spatial scales.

  5. Impacts of Fluvial Fine Sediments and Winter Storms on a Transgressive Shoal, off South-Central Louisiana, U.S.A

    Microsoft Academic Search

    D. Kobashi; F. Jose; G. W. Stone

    2007-01-01

    KOBASHI, D., JOSE, F., AND STONE, G.W., 2007. Impacts of Fluvial Fine Sediments and Winter Storms on a Transgressive Shoal, off South-Central Louisiana, U.S.A. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 858 - 862. Gold Coast, Australia, ISSN 0749.0208 Ship Shoal, a transgressive sand shoal off South-Central Louisiana and one of the potential sand

  6. Entrainment of Dungeness Crab in the Desdemona Shoals Reach of the Lower Columbia River Navigation Channel

    SciTech Connect

    Pearson, Walter H.; Kohn, Nancy P.; Skalski, J. R.

    2006-09-30

    Proposed dredging of the Columbia River has raised concerns about related impacts on Dungeness crab in the Columbia River Estuary (CRE). This study follows two major efforts, sponsored by the Portland District of the U. S. Army Corps of Engineers (USACE) to quantify the number of crabs entrained by a hopper dredge working in the CRE. From June 2002 through September 2002, Pacific Northwest National Laboratory (PNNL) conducted direct measurements of crab entrainment in the CRE from the mouth of the Columbia River (MCR, river mile -3 to +3) upriver as far as Miller Sands (river mile 21 to 24). These studies constituted a major step in quantifying crab entrainment in the CRE, and allowed statistically bounded projections of adult equivalent loss (AEL) for Dungeness crab populations under a range of future construction dredging and maintenance dredging scenarios (Pearson et al. 2002, 2003). In 2004, PNNL performed additional measurements to improve estimates of crab entrainment at Desdemona Shoals and at Flavel Bar, a reach near Astoria that had not been adequately sampled in 2002 (Figure 1). The 2004 data were used to update the crab loss projections for channel construction to 43 ft MLLW. In addition, a correlation between bottom salinity and adult (age 2+ and 3+, >100 mm carapace width) crab entrainment was developed using 2002 data, and elaborated upon with the 2004 data. This crab salinity model was applied to forecasting seasonal (monthly) entrainment rates and AEL using seasonal variations in salinity (Pearson et al. 2005). In the previous studies, entrainment rates in Desdemona Shoals were more variable than in any of the other reaches. Pearson et al. (2005) concluded that ?the dynamics behind the variable entrainment rates at Desdemona Shoals are not fully understood,? as well as finding that juvenile crab entrainment was not significantly correlated with salinity as it was for older crab. The present study was undertaken to address the question of whether the high age 1+ entrainment rate at Desdemona Shoals in June 2002 unusual, or would it be observed again under similar conditions? PNNL and USACE personnel directly measured crab entrainment by the USACE hopper dredge Essayons working in Desdemona Shoals in June 2006. In addition to quantifying crab entrainment of all age classes, bottom salinity was directly measured in as many samples as possible, so that the relationship between crab entrainment and salinity could be further evaluated. All 2006 data were collected and analyzed in a manner consistent with the previous entrainment studies (Pearson et al. 2002, 2003, 2005).

  7. Recombinant albumin and transthyretin transport proteins from two gull species and human: chlorinated and brominated contaminant binding and thyroid hormones.

    PubMed

    Ucán-Marin, Francisco; Arukwe, Augustine; Mortensen, Anne S; Gabrielsen, Geir W; Letcher, Robert J

    2010-01-01

    Environmentally relevant concentrations of selected polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) flame retardant congeners and their hydroxylated (OH) and methoxylated (MeO) analogues that can perturb thyroid hormone-dependent processes were comparatively examined with respect to competitive binding with thyroxine (T(4)) and 3,5,3'-triiodothyronine (T(3)) thyroid hormones (THs) on recombinant human and gull albumin and transthyretin transport proteins. The liver tissue was from glaucous gulls (Larus hyperboreus) from Norway and herring gulls (Larus argentatus) from the Great Lakes of North America. We isolated, cloned, sequenced, purified, and expressed the cDNA (cDNA) of albumin from liver of herring and glaucous gull. Albumin amino acid sequences were identical for both gull species. Concentration-dependent, competitive binding curves were generated for T(4) and T(3) binding alone and for selected substrates using gull and human recombinant albumin (recALB). Human recALB had high preference for T(4) relative to T(3), whereas it was reversed for gull recALB. Binding assays with recALB and recTTR gull proteins showed that relative to 2,2',4,4'-tetrabromoDE (BDE-47) and 2,2',3,4',5,5',6-heptaCB (CB-187) and the MeO-substituted (4-MeO-CB187 and 6-MeO-BDE47) analogues, 4-OH-CB187, 6-OH-BDE47, and 4'-OH-BDE49 had the greatest binding affinity and potency, and that competitive binding was greater for T(3) relative to T(4). These results indicate that xenobiotic ligand binding to human ALB or TTR cannot be used as a surrogate for gull binding interactions. The combination of TH-like brominated diphenyl ether backbone (relative to the chlorinated biphenyl backbone), and the presence of OH-group produced a more effective competitive ligand on human and gull recALB and recTTR relative to both T(3) and T(4). This suggests the possibility that OH-substituted organohalogen contaminants may be an exposure concern to the thyroid system in free-ranging gulls as well as for humans. PMID:20039755

  8. [Comments on the exchangeability of herring-gull chicks (Larus argentatus) after the 1st week of life].

    PubMed

    Berens von Rautenfeld, D

    1978-06-01

    In the Biville chalk cliff area the Herring gulls nest both in slope and ground colonies and on cliff ledges. Like the Kittiwake (CULLEN 1957), the cliff-nesting pairs still accept other chicks after the 1st week of life. Gulls in slope and ground colonies, however, attack those chicks older than 4 days in close proximity to their nests (TINBERGEN 1936). PMID:696024

  9. Proximate and Ultimate Causation of Egg Size and the "Third-Chick Disadvantage" in the Western Gull

    E-print Network

    Pierotti, Raymond; Bellrose, Cheryl A.

    1986-04-01

    Department of Biological Sciences, San Jose State University, San Jose, California 95192 USA ABSTRACT.--It is generally observed in gulls (Larus spp.) that produce a typical clutch of three that the third- or last-laid egg is smaller and lighter than its... interpretations have been suggested to explain its adap- tive basis. We report on egg size, chick growth, and survival in a population of Western Gulls (Larus occidentalis) where the third-chick disadvantage appeared to be nonexistent. We suggest...

  10. Sarcocystis sp. from the herring gull ( Larus argentatus ) identity to Sarcocystis wobeseri based on cyst morphology and DNA results

    Microsoft Academic Search

    Petras Prakas; Liuda Kutkien?; Aniolas Sruoga; Dalius Butkauskas

    Having studied 11 herring gulls (Larus argentatus) Sarcocystis cysts were found in neck and leg muscles of 4 birds. One type of sarcocysts (cyst type I) that have a thin (?1.0 ?m), smooth,\\u000a or slightly wavy cyst wall without clearly visible protrusions and small (6.0–8.0 ?m) lancet- or banana-shaped cystozoites\\u000a was identified by the light microscopy. Sarcocysts extracted from one herring gull

  11. Abundance and characteristics of the recreational water quality indicator bacteria Escherichia coli and enterococci in gull faeces

    USGS Publications Warehouse

    Fogarty, L.R.; Haack, S.K.; Wolcott, M.J.; Whitman, R.L.

    2003-01-01

    Aims: To evaluate the numbers and selected phenotypic and genotypic characteristics of the faecal indicator bacteria Escherichia coli and enterococci in gull faeces at representative Great Lakes swimming beaches in the United States. Methods and Results: E. coli and enterococci were enumerated in gull faeces by membrane filtration. E. coli genotypes (rep-PCR genomic profiles) and E. coli (Vitek?? GNI+) and enterococci (API?? rapid ID 32 Strep and resistance to streptomycin, gentamicin, vancomycin, tetracycline and ampicillin) phenotypes were determined for isolates obtained from gull faeces both early and late in the swimming season. Identical E. coli genotypes were obtained only from single gull faecal samples but most faecal samples yielded more than one genotype (median of eight genotypes for samples with 10 isolates). E. coli isolates from the same site that clustered at ???85% similarity were from the same sampling date and shared phenotypic characteristics, and at this similarity level there was population overlap between the two geographically isolated beach sites. Enterococcus API?? profiles varied with sampling date. Gull enterococci displayed wide variation in antibiotic resistance patterns, and high-level resistance to some antibiotics. Conclusions: Gull faeces could be a major contributor of E. coli (105-109 CFU g-1) and enterococci (104-108 CFU g-1) to Great Lakes recreational waters. E. coli and enterococci in gull faeces are highly variable with respect to their genotypic and phenotypic characteristics and may exhibit temporal or geographic trends in these features. Significance and Impact of the Study: The high degree of variation in genotypic or phenotypic characteristics of E. coli or enterococci populations within gull hosts will require extensive sampling for adequate characterization, and will influence methods that use these characteristics to determine faecal contamination sources for recreational waters.

  12. Mercury Concentration in 3 Species of Gulls, Larus ridibundus, Larus minutus, Larus canus, From South Coast of the Caspian Sea, Iran

    Microsoft Academic Search

    Fateme Rajaei; Abbas Esmaili Sari; Nader Bahramifar; Seyed Mahmoud Ghasempouri

    2010-01-01

    In this study, the mercury concentrations of liver, breast feathers and tail feathers in three species of Gull; Black-headed\\u000a Gull (Larus ridibundus), Common Gull (Larus canus) and Little Gull (Larus minutus) from the South coast of the Caspian Sea in Iran were assayed. Mercury accumulation in liver, breast feathers and tail feathers\\u000a of species were 1.69–3.16, 2.88–7.18 and 2.09–5.66 mg\\/kg, respectively.

  13. California gull chicks raised near colony edges have elevated stress levels

    USGS Publications Warehouse

    Herring, Garth; Ackerman, Joshua T.

    2011-01-01

    Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers.

  14. Occurrence of acanthocephalans in largemouth bass and smallmouth bass (Centrarchidae) from Gull Lake, Michigan.

    PubMed

    Muzzall, Patrick M; Gillilland, Merritt G

    2004-06-01

    A total of 65 largemouth bass, Micropterus salmoides, and 27 smallmouth bass, M. dolomieu, collected in April-September 2000 and April-July 2001 from Gull Lake, Michigan, were examined for acanthocephalans. Leptorhynchoides thecatus and Neoechinorhynchus cylindratus infected all the bass examined. Leptorhynchoides thecatus had the highest mean intensity (258.2 +/- 185.4 in 2000 and 145.0 +/- 61.0 in 2001) of the species infecting smallmouth bass. Although N. cylindratus had higher mean intensities (42.1 +/- 37.9 in 2000 and 68.9 +/- 70.5 in 2001) than did L. thecatus in largemouth bass, the values were not significantly different between bass species. The prevalence, mean intensity, and mean abundance of Pomphorhynchus bulbocolli in the bass species were below the values for the other acanthocephalan species. Leptorhynchoides thecatus and N. cylindratus are the most abundant intestinal helminths in bass from Gull Lake. PMID:15270122

  15. California gull chicks raised near colony edges have elevated stress levels.

    PubMed

    Herring, Garth; Ackerman, Joshua T

    2011-08-01

    Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers. PMID:21596043

  16. Audouin's gull, a potential vehicle of an extended spectrum ?-lactamase producing Salmonella Agona.

    PubMed

    Antilles, Noelia; Garcia-Migura, Lourdes; Joensen, Katrine Grimstrup; Leekitcharoenphon, Pimlapas; Aarestrup, Frank M; Cerdà-Cuéllar, Marta; Hendriksen, Rene S

    2015-01-01

    The genome of a multidrug-resistant Salmonella Agona isolated from Larus audouinii (Audouin's gull) in Spain was examined. The isolate showed high levels of resistance to different antimicrobials, including third generation cephalosporins and fluoroquinolones, which is a public health concern as those being used to treat severe salmonellosis in humans. Whole genome sequencing revealed the strain being multilocus sequence type ST13, and eight resistance genes (aadA2, aadB, blaCTX-M-9,blaDHA-1, qnrA1, tetA, sul1 and dfrA16) belonging to seven antimicrobial classes were confirmed, as well as the presence of two plasmids. Migratory Audouin's gulls have the ability to cover long distances during annual movements. Therefore, they have the potential to disseminate multidrug-resistant Salmonella and resistance genes in the environment and over great geographic distances, contributing to the global dissemination of resistance genes. PMID:25673651

  17. Anthropogenic input of heavy metals in two Audouin's gull breeding colonies.

    PubMed

    García-Tarrasón, Manuel; Pacho, Sergio; Jover, Lluís; Sanpera, Carolina

    2013-09-15

    Anthropogenic activities have become an important source of heavy metals to the marine environments. Biological sentinels like seabirds' chicks have been widely used to monitorize the levels of some heavy metals. Due to its mainly marine foraging habits, Audouin's gull fits well for this purpose. Mercury and lead levels were measured in mantle feathers of Audouin's gull chicks from two colonies in NE Iberian Peninsula: the Ebro Delta and the Llobregat Delta. Both are anthropized areas subject to differential pollutant inputs. Lead levels were significantly higher in the Llobregat Delta probably due to the use of leaded fuel in the nearby Barcelona airport. On the other side, mercury concentrations were higher in the Ebro Delta, in relation with the disposal of the toxic sediments at the Flix site carried down by the Ebro River. These mercury levels in the Ebro chicks reached values that have been described as toxic. PMID:23871579

  18. Chewing lice (Phthiraptera: Amblycera, Ischnocera) from Red Sea gulls with new host-parasite records.

    PubMed

    Al-Ahmed, Azzam; Shobrak, Mohammed; Nasser, Mohamed G E-D

    2014-01-01

    Knowledge about chewing lice from marine birds of the Red Sea is minimal. Five species of gulls were examined for chewing lice in three different localities of the Saudi Arabian Red Sea coast. Two gull species were examined for lice for the first time (Larus armenicus Buturlin, 1934 and Larus michahellis Naumann, 1840) and their lice represent new host-louse associations. Four species and two subspecies of lice were identified from 159 specimens collected. Actornithophilus piceus lari (Packard, 1870) and Austromenopon transversum (Denny, 1842) (suborder: Amblycera), and Quadraceps punctatus (Burmeister, 1838) and Saemundssonia lari (O. Fabricius, 1780) (suborder: Ischnocera) were recorded for the first time from Saudi Arabia and Red Sea birds. Taxonomic and ecological notes, type hosts, data on specimens examined, collecting localities, an identification key, and photographs of each species and subspecies are given.  PMID:24869888

  19. Islands at bay: Rising seas, eroding islands, and waterbird habitat loss in Chesapeake Bay (USA)

    USGS Publications Warehouse

    Erwin, R.M.; Brinker, D.F.; Watts, B.D.; Costanzo, G.R.; Morton, D.D.

    2011-01-01

    Like many resources in the Chesapeake Bay region of the U. S., many waterbird nesting populations have suffered over the past three to four decades. In this study, historic information for the entire Bay and recent results from the Tangier Sound region were evaluated to illustrate patterns of island erosion and habitat loss for 19 breeding species of waterbirds. Aerial imagery and field data collected in the nesting season were the primary sources of data. From 1993/1994 to 2007/2008, a group of 15 islands in Tangier Sound, Virginia were reduced by 21% in area, as most of their small dunes and associated vegetation and forest cover were lost to increased washovers. Concurrently, nesting American black ducks (Anas rubripes) declined by 66%, wading birds (herons-egrets) by 51%, gulls by 72%, common terns (Sterna hirundo) by 96% and black skimmers (Rynchops niger) by about 70% in this complex. The declines noted at the larger Bay-wide scale suggest that this study area maybe symptomatic of a systemic limitation of nesting habitat for these species. The island losses noted in the Chesapeake have also been noted in other Atlantic U. S. coastal states. Stabilization and/or restoration of at least some of the rapidly eroding islands at key coastal areas are critical to help sustain waterbird communities. ?? 2010 US Government.

  20. The value and vulnerability of small estuarine islands for conserving metapopulations of breeding waterbirds

    USGS Publications Warehouse

    Erwin, R.M.; Hatfield, J.S.; Wilmers, T.J.

    1995-01-01

    Compelling arguments for preserving large habitat 'islands' have been made for a number of animal groups, but most commonly for terrestrial birds. We argue that, for many species of waterbirds nesting in coastal estuaries, maintaining numerous small islands may be a more effective management strategy than maintaining larger islands or reserves. In this study, the number of great white heron Ardea herodias nests over a 5-year period (1986-91) was negatively correlated with island area in the Florida Keys, USA. Nest densities were highest in the 210 ha island size range and lowest for islands larger than 100 ha. These small islands also attract nesting black skimmers Rynchops niger, brown pelicans Pelecanus occidentalis, and several species of terns and gulls. Small estuarine islands are vulnerable to sea level rise, erosion from watercraft, and, for dredge material islands, lack of sufficient maintenance because of competing needs for beach nourishment. Managers need to enforce more buffering and protection of these islands and argue for more dredged material allocations in some areas.

  1. Individual differences in nest defense in the colonial breeding Black-tailed Gulls

    Microsoft Academic Search

    Kentaro Kazama; Yutaka Watanuki

    2010-01-01

    Often in colonial seabirds, all colony members are believed to defend against nest predators and experience equal nest predation\\u000a risk. However, the variation of defense behavior among members and its reproductive consequences are largely unknown. We investigated\\u000a (1) individual variation in the nest defense of breeding Black-tailed Gulls Larus crassirostris against a natural egg predator, the Jungle Crow Corvus macrorhynchos

  2. How costly is clutch formation in the Audouin's Gull Larus audouinii?

    Microsoft Academic Search

    Xavier Ruiz; Lluis Jover; Vittorio Pedrocchi; Daniel Oro; Jacob Gonzalez-Soli' s

    2000-01-01

    During the Audouin's Gull's breeding season at the Ebro Delta in 1993, 24 fresh eggs from eight three-egg clutches (modal clutch-size) were collected at the peak of the laying period. Eggs were processed to obtain formalin-fixed yolks, which were halved and stained using the potassium dichromate method. Digitized images of the yolks were examined to assess the daily rates of

  3. Development and validation of a herring gull embryo toxicokinetic model for PCBs.

    PubMed

    Drouillard, Ken G; Norstrom, Ross J; Fox, Glen A; Gilman, Andy; Peakall, David B

    2003-01-01

    A toxicokinetic model was developed to describe polychlorinated biphenyl (PCB) accumulation by herring gull (Larus argentatus) embryos during development. The model consists of two components, a bioenergetics model that predicts the lipid mass balance of embryo and yolk compartments with time and an empirical toxicokinetic model that describes PCB partitioning between lipid compartments in the egg. The model was calibrated using data on PCB and lipid partitioning between embryo and yolk + albumen at four time points during incubation in herring gull eggs injected with a PCB mixture, combined with data sets on herring gull embryo growth rates and bioenergetic demands with time. The model was validated using independent data consisting of maternally exposed, field-incubated Lake Superior herring gull eggs that varied in incubation ages over the range of 8.5 d to pipping age (26-28 days). PCB concentrations in 6-9 d embryos were nearly an order of magnitude less than predicted by equilibrium lipid partitioning between the embryo and yolk + albumen compartments of the eggs. PCB concentrations in embryos were adequately predicted by equilibrium partitioning, however, for eggs incubated for 23-28 d. An empirical relationship was developed to account for the apparent nonequilibrium behaviour of PCBs during early development. The model was sensitive to the mass of yolk lipids and the mass of PCBs deposited to fresh eggs and much of the variability in embryo PCB concentrations could by explained by accounting for variability in these input parameters. Consistent with experimental data for other avian species, the model predicts that the highest PCB concentrations in the embryo/chick occur during pipping or soon after when yolk lipids have been completely resorbed by the embryo. PMID:12739857

  4. Food availability and nest predation influence life history traits in Audouin's gull, Larus audouinii

    Microsoft Academic Search

    Daniel Oro; Roger Pradel; Jean-Dominique Lebreton

    1999-01-01

    The effects of food availability and nest predation on several life history traits such as adult survival, dispersal, and\\u000a reproductive performance were assessed in an Audouin's gull (Larus audouinii) colony during the period 1992–1997. The amounts of fish discarded from trawlers were used as a measure of food availability,\\u000a and a trawling moratorium which partially overlapped with the breeding season

  5. Concentration and Effects of Selenium in California Gulls Breeding on the Great Salt Lake

    Microsoft Academic Search

    Michael R. Conover; John Luft

    We examined selenium concentrations in California gulls (Larus californicus) nesting on the Great Salt Lake, Utah during 2006 and 2007. During 2006, the mean selenium concentration (+ SE) in adult blood samples was 18.1 + 1.5 µg\\/g (n = 35) on a dry weight basis, 8.1 + 0.4 in adult liver samples (n = 36), and 3.0 + 0.10 µg\\/g

  6. Stealing bivalves from common eiders: kleptoparasitism by glaucous gulls in spring

    Microsoft Academic Search

    Øystein Varpe

    2010-01-01

    Here I report on glaucous gulls (Larus hyperboreus), an opportunistic, generalist predator, stealing bivalves from a diving duck, the common eider (Somateria mollissima). The study took place in spring, the pre-breeding period of the common eider, in an Arctic fjord (Adventfjorden) at western\\u000a Spitsbergen, Svalbard. Eiders were abundant, their presence predictable, and they fed on large prey requiring surface handling—all

  7. Relationships between PCB levels, hepatic EROD activity and plasma retinol in glaucous gulls, Larus hyperboreus

    Microsoft Academic Search

    E. O. Henriksen; G. W. Gabrielsen; J. U. Skaare; N. Skjegstad; B. M. Jenssen

    1998-01-01

    Fifteen adult glaucous gulls, Larus hyperboreus, were captured in the vicinity of Ny-Ålesund, Svalbard. The birds were kept captured and fed a diet of polar cod, Boreogadus saida, caught off the coast of Spitsbergen. After 40 days of captivity, the birds were killed. The presence of hepatic homologues to mammalian CYP1A and CYP2B proteins was demonstrated by Western blotting. High

  8. Persistent organic pollutants and mercury in dead and dying glaucous gulls (Larus hyperboreus) at Bjørnøya (Svalbard).

    PubMed

    Sagerup, Kjetil; Helgason, Lisa B; Polder, Anuschka; Strøm, Hallvard; Josefsen, Terje D; Skåre, Janneche U; Gabrielsen, Geir W

    2009-11-15

    Dead and dying glaucous gulls (Larus hyperboreus) were collected on Bjørnøya in the Barents Sea in 2003, 2004 and 2005. Autopsies of the seabirds only explained a clear cause of death for three (14%) of the 21 birds. A total of 71% of the birds were emaciated. Liver and brain samples were analysed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ether (PBDEs), hexabromocyclododecanes (HBCDs) and mercury (Hg). High levels of SigmaOCPs, SigmaPCBs, SigmaPBDEs and alpha-HBCD were found in liver and brain. Compared to the dead and dying glaucous gulls found 1989, the congeners' composition tended to change toward more persistent compounds in the 2003-2005 samples. The brain levels of OCPs and PCBs did not differ between 1989 and 2003-2005, while the liver levels were significantly lower. The brain/liver ratio for PCB and PBDE significantly decreased with halogenations of the molecule, indicating a clear discrimination of highly halogenated PCBs and PBDEs entering the brain. There was further a clear negative correlation between contaminant concentrations and body condition. The brain levels were not as high as earlier published lethal levels of p,p'-DDE or PCB. However, more recent studies reported a range of sub-lethal OCP- and PCB-related effects in randomly sampled glaucous gulls. An additional elevation of pollutants due to emaciation may increase the stress of the already affected birds. The high brain levels of OCP, PCB and PBDE of present study might therefore have contributed to the death of weakened individuals of glaucous gull. PMID:19735935

  9. Organochlorines and Possible Biochemical Effects in Glaucous Gulls ( Larus hyperboreus ) from Bjørnøya, the Barents Sea

    Microsoft Academic Search

    E. O. Henriksen; G. W. Gabrielsen; S. Trudeau; J. Wolkers; K. Sagerup; J. U. Skaare

    2000-01-01

    .   To study possible biochemical effects of organochlorine contaminants (OCs) in glaucous gulls (Larus hyperboreus), 40 adult individuals were collected from colonies on Bjørnøya in the Barents Sea. OCs (four pesticides and nine PCB congeners),\\u000a microsomal 7-ethoxyresorufin O-deethylase (EROD) activity, microsomal testosterone hydroxylation, highly carboxylated porphyrins\\u000a (HCPs), retinol, and retinyl palmitate were quantified in liver samples. The hepatic vitamin A

  10. Evaluating gull diets: A comparison of conventional methods and stable isotope analysis

    USGS Publications Warehouse

    Weiser, E.L.; Powell, A.N.

    2011-01-01

    Samples such as regurgitated pellets and food remains have traditionally been used in studies of bird diets, but these can produce biased estimates depending on the digestibility of different foods. Stable isotope analysis has been developed as a method for assessing bird diets that is not biased by digestibility. These two methods may provide complementary or conflicting information on diets of birds, but are rarely compared directly. We analyzed carbon and nitrogen stable isotope ratios of feathers of Glaucous Gull (Larus hyperboreus) chicks from eight breeding colonies in northern Alaska, and used a Bayesian mixing model to generate a probability distribution for the contribution of each food group to diets. We compared these model results with probability distributions from conventional diet samples (pellets and food remains) from the same colonies and time periods. Relative to the stable isotope estimates, conventional analysis often overestimated the contributions of birds and small mammals to gull diets and often underestimated the contributions of fish and zooplankton. Both methods gave similar estimates for the contributions of scavenged caribou, miscellaneous marine foods, and garbage to diets. Pellets and food remains therefore may be useful for assessing the importance of garbage relative to certain other foods in diets of gulls and similar birds, but are clearly inappropriate for estimating the potential impact of gulls on birds, small mammals, or fish. However, conventional samples provide more species-level information than stable isotope analysis, so a combined approach would be most useful for diet analysis and assessing a predator's impact on particular prey groups. ?? 2011 Association of Field Ornithologists.

  11. Shoaling behaviour enhances risk of predation from multiple predator guilds in a marine fish.

    PubMed

    Ford, John R; Swearer, Stephen E

    2013-06-01

    Predicting the consequences of predator biodiversity loss on prey requires an understanding of multiple predator interactions. Predators are often assumed to have independent and additive effects on shared prey survival; however, multiple predator effects can be non-additive if predators foraging together reduce prey survival (risk enhancement) or increase prey survival through interference (risk reduction). In marine communities, juvenile reef fish experience very high mortality from two predator guilds with very different hunting modes and foraging domains-benthic and pelagic predator guilds. The few previous predator manipulation studies have found or assumed that mortality is independent and additive. We tested whether interacting predator guilds result in non-additive prey mortality and whether the detection of such effects change over time as prey are depleted. To do so, we examined the roles of benthic and pelagic predators on the survival of a juvenile shoaling zooplanktivorous temperate reef fish, Trachinops caudimaculatus, on artificial patch reefs over 2 months in Port Phillip Bay, Australia. We observed risk enhancement in the first 7 days, as shoaling behaviour placed prey between predator foraging domains with no effective refuge. At day 14 we observed additive mortality, and risk enhancement was no longer detectable. By days 28 and 62, pelagic predators were no longer significant sources of mortality and additivity was trivial. We hypothesize that declines in prey density led to reduced shoaling behaviour that brought prey more often into the domain of benthic predators, resulting in limited mortality from pelagic predators. Furthermore, pelagic predators may have spent less time patrolling reefs in response to declines in prey numbers. Our observation of the changing interaction between predators and prey has important implications for assessing the role of predation in regulating populations in complex communities. PMID:23124272

  12. Synchronous response of hydrophobic chemicals in herring gull eggs in the Great Lakes

    SciTech Connect

    Smith, D.W. [BCM Engineers, Inc., Plymouth Meeting, PA (United States)

    1994-12-31

    Short-term changes in hydrophobic organic chemical concentrations in gull eggs are synchronized within and across the Great Lakes. Deviations from long-term trends for PCBs, DDE, dieldrin, mirex, and hexachlorobenzene in Lake Superior gull eggs correlate with deviations of those chemicals in gull eggs from Lake Ontario and, to a lesser extent, the other Great Lakes. This synchrony is inconsistent with the hypothesis that changes in tissue levels are controlled by changes in external loading. Rather, the synchrony implies that some overriding factor -- probably weather -- concurrently affects internal recycling of chemicals across chemicals across the Great Lakes. From 1980 to 1992, deviations from long-term weather patterns correlated significantly with deviations of some hydrophobic chemicals. A weather-driven hypothesis implies that (1) apparent changes in the rate of chemical decline result from uncontrollable changes in internal recycling as opposed to potentially controllable inputs from external sources and (2) the current period of slow contaminant decline is likely to be a short-term phenomenon.

  13. Effects of varying temporal exposure to lead on behavioral development in herring gull (Larus argentatus) chicks.

    PubMed

    Burger, J; Gochfeld, M

    1995-11-01

    In humans and other animals, lead exposure in infants and young animals affects anatomic, physiologic, behavioral, and intellectual development. Yet it is largely unknown whether the effects occur gradually or are more pronounced if exposure occurs at particular stages. In this article we examine the effects of temporal differences in lead exposure on early behavioral development in herring gulls (Larus argentatus). We randomly assigned 64 1-2-day-old gull chicks to one of four treatment groups to receive a lead acetate dose at age 6 days (100 micrograms/g) or 12 days (50 or 100 micrograms/g), or to receive matched volume saline injections on the same days. Behavioral tests were performed at 2-5-day intervals to examine locomotion, balance, righting response, thermoregulation, and visual cliff. Flight behavior was examined at fledging. Results were compared with previously studied exposures at 2, 4, and 6 days of age. Righting response and balance were disrupted immediately after exposure, regardless of the timing of exposure. Thermoregulatory, visual cliff, and individual recognition behavior were more affected by exposure at 2-6 days, and there was little effect with exposure at 12 days. These results confirm the existence of critical periods for certain behaviors to lead exposure in developing herring gulls. PMID:8545481

  14. Adrenocortical function of Arctic-breeding glaucous gulls in relation to persistent organic pollutants.

    PubMed

    Verboven, Nanette; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Evans, Neil P

    2010-03-01

    Unpredictable changes in the environment stimulate the avian hypothalamo-pituitary-adrenal axis to produce corticosterone, which induces behavioural and metabolic changes that enhance survival in the face of adverse environmental conditions. In addition to profound environmental perturbations, such as severe weather conditions and unpredictable food shortages, many Arctic-breeding birds are also confronted with chronic exposure to persistent organic pollutants (POPs), some of which are known to disrupt endocrine processes. This study investigated the adrenocortical function of a top predator in the Arctic marine environment, the glaucous gull (Larus hyperboreus). High concentrations of organochlorines, brominated flame retardants and metabolically-derived products in blood plasma of incubating glaucous gulls were associated with high baseline corticosterone concentrations in both sexes and a reduced stress response in males. Contaminant-related changes in corticosterone concentration occurred over and above differences in body condition and seasonal variation. Chronically high corticosterone concentrations and/or a compromised adrenocortical response to stress can have negative effects on the health of an individual. The results of the present study suggest that exposure to POPs may increase the vulnerability of glaucous gulls to environmental stressors and thus could potentially compromise their ability to adapt to the rapidly changing environmental conditions associated with climate change that are currently seen in the Arctic. PMID:19932109

  15. Antibiotic resistance patterns in Escherichia coli from gulls in nine European countries

    PubMed Central

    Stedt, Johan; Bonnedahl, Jonas; Hernandez, Jorge; McMahon, Barry J.; Hasan, Badrul; Olsen, Björn; Drobni, Mirva; Waldenström, Jonas

    2014-01-01

    Background The prevalence of antibiotic resistant faecal indicator bacteria from humans and food production animals has increased over the last decades. In Europe, resistance levels in Escherichia coli from these sources show a south-to-north gradient, with more widespread resistance in the Mediterranean region compared to northern Europe. Recent studies show that resistance levels can be high also in wildlife, but it is unknown to what extent resistance levels in nature conform to the patterns observed in human-associated bacteria. Methods To test this, we collected 3,158 faecal samples from breeding gulls (Larus sp.) from nine European countries and tested 2,210 randomly isolated E. coli for resistance against 10 antibiotics commonly used in human and veterinary medicine. Results Overall, 31.5% of the gull E. coli isolates were resistant to ?1 antibiotic, but with considerable variation between countries: highest levels of isolates resistant to ?1 antibiotic were observed in Spain (61.2%) and lowest levels in Denmark (8.3%). For each tested antibiotic, the Iberian countries were either the countries with the highest levels or in the upper range in between-country comparisons, while northern countries generally had a lower proportion of resistant E. coli isolates, thereby resembling the gradient of resistance seen in human and food animal sources. Conclusion We propose that gulls may serve as a sentinel of environmental levels of antibiotic resistant E. coli to complement studies of human-associated microbiota. PMID:24427451

  16. Validation, Proof-of-Concept, and Postaudit of the Groundwater Flow and Transport Model of the Project Shoal Area

    SciTech Connect

    Ahmed Hassan

    2004-09-01

    The groundwater flow and radionuclide transport model characterizing the Shoal underground nuclear test has been accepted by the State of Nevada Division of Environmental Protection. According to the Federal Facility Agreement and Consent Order (FFACO) between DOE and the State of Nevada, the next steps in the closure process for the site are then model validation (or postaudit), the proof-of-concept, and the long-term monitoring stage. This report addresses the development of the validation strategy for the Shoal model, needed for preparing the subsurface Corrective Action Decision Document-Corrective Action Plan and the development of the proof-of-concept tools needed during the five-year monitoring/validation period. The approach builds on a previous model, but is adapted and modified to the site-specific conditions and challenges of the Shoal site.

  17. Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test

    SciTech Connect

    K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

    2004-03-01

    The purpose of this work is to characterize groundwater flow and contaminant transport at the Shoal underground nuclear test through numerical modeling using site-specific hydrologic data. The ultimate objective is the development of a contaminant boundary, a model-predicted perimeter defining the extent of radionuclide-contaminated groundwater from the underground test throughout 1,000 years at a prescribed level of confidence. This boundary will be developed using the numerical models described here, after they are approved for that purpose by DOE and NDEP.

  18. The Svalbard glaucous gull as bioindicator species in the European arctic: insight from 35 years of contaminants research.

    PubMed

    Verreault, J; Gabrielsen, G W; Bustnes, J O

    2010-01-01

    Biomonitoring survey conducted with glaucous gulls from Svalbard have demonstrated that this top-predator-scavenger species accumulates a wide array of chemicals of environmental concern, including organohalogens, trace elements, organometals, and several non-halogenated and non-metallic-compounds. Among these contaminants are those subjected to global bans or restrictions in North America and Europe (e.g., legacy OC's, penta-, and octa-PBDE technical mixtures and mercury). In addition, some currently produced chemicals were found in gulls that lack and global use regulation (e.g., deca-PBDE , HBCD, and other non-PBDE BFR additives, siloxanes, and selected PFASs). Svalbard glaucous gulls are also exposed to contaminant metabolites that, at time, are more bioactive than their precursors (e.g., oxychlordane, p,p'-DDE, OH- and MeSo2-PCBs, and OH-PBDEs) Concentrations of legacy OCs (PCBs, DDTs, CHLs, CBzs, dieldrin, PCDD/Fs, and mirec) in tissues, blood, and eggs of Svalbard glaucous gulls have displayed the highest contamination levels among glaucous gull populations that inhabit Greenland (Cleemann et al. 2000) Jan Mayen (Gabrielsen et al. 1997), Alaska (Vander Pol et al. 2009), and the Canadian Arctic (Braune et a. 2005). To date, measurements obtaines on more novel organohalogens (e.g., OH- and MeSo2-containing metabolites, BFRs and PFASs) in Svalbard glaucous gull samples generally confirm that the spatial and trophodynamic trends of the legacy OC concentrations, whereas no clear trend emerges from surveys of trace elements and organometals. Using the glaucous gull as biosentinel species provides clear evidence that Svalbard and the European Arctic environment is exposed to a complex mixture of legacy and more recently introduced PBT-like substances. PMID:20044795

  19. Earth Island

    NSDL National Science Digital Library

    The Earth Island Web site is maintained by the Earth Island Institute (EII). EII also publishes the Earth Island Journal quarterly. The current issue of the journal can be browsed by section or by subject, and offers current news, world reports, and feature articles on a wide range of environmental subject areas. Earth Island also undertakes a number of projects that are discussed at the site as well as in a portion of the journal. The entire site is searchable. This is an excellent site for those interested in keeping up on environmental issues.

  20. Reorganization of Miocene Deep Water Circulation in Response to the Shoaling of the Central American Seaway

    NASA Astrophysics Data System (ADS)

    Nisancioglu, K. H.; Stone, P. H.

    2001-05-01

    The response of ocean circulation to the shoaling of the Central American Seaway (CAS) is investigated using the MIT Ocean General Circulation Model. In contrast to earlier model studies, it is found that deep water is formed in the North Atlantic prior to the closure of the CAS. However, the circulation pattern is fundamentally different from the modern ocean. In the upper layers of the CAS, there is a relatively strong geostrophic flow from the Pacific to the Atlantic, controlled by the pressure difference across the seaway. However, when the CAS is deeper than the level of North Atlantic Deep Water (NADW) outflow, a significant amount of NADW passes through the CAS to the Pacific Ocean. In the Pacific, the deep water traverses the basin from east to west in a relatively narrow zonal jet, and becomes a southward flowing western boundary current, before it joins with the Antarctic Circumpolar Current (ACC) to the south. This implies that deep sea sediment records from the Pacific could have been influenced by relatively young NADW. Diversification of benthic foraminifer fauna suggest that the CAS shoaled to a depth of about 1000 m towards the end of the middle Miocene. This would have prevented the passage of NADW to the Pacific, and established the modern deepwater circulation pattern.

  1. Reorganization of Miocene deep water circulation in response to the shoaling of the Central American Seaway

    NASA Astrophysics Data System (ADS)

    Nisancioglu, Kerim H.; Raymo, Maureen E.; Stone, Peter H.

    2003-03-01

    The response of ocean circulation to the shoaling of the Central American Seaway (CAS) is investigated using the Massachusetts Institute of Technology (MIT) Ocean General Circulation Model (OGCM). In contrast to earlier model studies, it is found that significant amounts of deep water are formed in the North Atlantic prior to the closure of the CAS. However, the circulation pattern is fundamentally different from the modern ocean. In the upper layers of the CAS, there is a relatively strong geostrophic flow from the Pacific to the Atlantic, controlled by the pressure difference across the seaway. However, when the CAS is deeper than the level of North Atlantic Deep Water (NADW) outflow, a significant amount of NADW passes through the CAS to the Pacific Ocean. In the Pacific, the deep water traverses the basin from east to west in a relatively narrow zonal jet, and becomes a southward flowing western boundary current, before it joins with the Antarctic Circumpolar Current (ACC) to the south. This implies that deep sea sediment records from the Miocene Pacific Ocean could have been influenced by relatively young NADW and provides a new framework for the interpretation of geochemical tracer data. Diversification of benthic foraminifer fauna suggests that the CAS shoaled to a depth of about 1000 m toward the end of the middle Miocene. This would have prevented the passage of NADW to the Pacific and established the modern deep water circulation pattern at that time.

  2. Annual Variation in Numbers of Breeding California Gulls at Mono Lake, California: the Importance of Natal Philopatry and Local and Regional Conditions

    Microsoft Academic Search

    Peter H. Wrege; W. David Shuford; David W. Winkler; Robert Jellison

    2006-01-01

    The California Gull (Larus californicus) breeding colony at Mono Lake, California, is the second largest in the world, but its size can fluctuate annually by .45%. We examined six groups of factors that potentially could affect the numbers of pairs nesting each year, including availability of nesting habitat, numbers of potential breeding gulls, environmental conditions along the Pacific coast in

  3. Will free-ranging predators stop depredating untreated eggs in pulegone-scented gull nests after exposure to pulegone-injected eggs?

    Microsoft Academic Search

    Michael R. Conover; Kimberly S. Lyons

    2005-01-01

    Pulegone is a chemical derived from plants of the mint family (Mentha spp.) that irritates the trigeminal nerve of mammals when inhaled and causes gastric distress when consumed. We examined whether free-ranging mammalian predators would stop depredating untreated eggs in gulls’ nests that smelled of pulegone. Prior to the nesting period, we distributed pulegone-injected eggs around a gull colony so

  4. Polychlorinated biphenyls in diseased lesser black-backed gull (Larus fuscus fuscus) chicks from the Gulf of Finland.

    PubMed

    Hario, M; Himberg, K; Hollmén, T; Rudbäck, E

    2000-01-01

    Diseases due to the degeneration of the liver and various other internal organs were the major cause of the exceedingly high chick mortality in lesser black-backed gulls (Larus fuscus fuscus) in the central Gulf of Finland, Baltic Sea, during 1991-1993. The same symptoms were found in chicks of common gulls (Larus canus) and herring gulls (Larus argentatus) from the same focal area, although at a much lower frequency. We found disproportionately high concentrations of polychlorinated biphenyls (PCBs) in liver relative to leg muscle in lesser black-backed chicks compared with common gull and herring gull chicks. The causality between PCB residues and chick diseases remains unknown. No signs of chick edema disease or abnormal frequency of embryonic deaths, commonly associated with organochlorines in biota, were found. It is concluded that studies made in a very small geographical area may not give a good correlation between dose and effect due to an even greater variation in tolerance. Another explanation is that the diseases may not have been PCB-induced. PMID:15093008

  5. Diets of nesting laughing gulls (Larus atricilla) at the Virginia Coast Reserve: observations from stable isotope analysis

    USGS Publications Warehouse

    Knoff, A.J.; Macko, S.A.; Erwin, R.M.

    2001-01-01

    Food web studies often ignore details of temporal, spatial, and intrapopulation dietary variation in top-level consumers. In this study, intrapopulation dietary variation of a dominant carnivore, the Laughing Gull (Larus atricilla), was examined using carbon, nitrogen, and sulfur isotope analysis of gull tissues as well as their prey (fish, invertebrates, and insects) from the Virginia Coast Reserve estuarine system. As earlier traditional diet studies found evidence of individual dietary specialization within gull populations, this study used stable isotope analysis to assess specialization in a coastal Laughing Gull population. Specifically, blood, muscle, and feather isotope values indicated significant intrapopulation dietary specialization. Some gulls relied more heavily on estuarine prey (mean blood ?13C = -17.5, ?15N = 12.6, and ?34S = 9.3), whereas others appeared to consume more foods of marine origin (mean blood ?13C = -19.4, ?15N = 14.8, and ?34S = 10.4). It is important to account for such dietary variability when assessing trophic linkages in dynamic estuarine systems.

  6. Island Hopping

    ERIC Educational Resources Information Center

    Bennett, Gayle

    2009-01-01

    At some institutions, it may feel as though faculty live on one island and advancement staff on another. The islands form part of an archipelago, and they exchange ambassadors and send emissaries occasionally, but interactions are limited. It may even seem as though the two groups speak different languages, deal in different currencies, and abide…

  7. [On a helminthofauna of seabirds of the Archangelskaya Bay ( Northern island of Novaya Zemlya)].

    PubMed

    Kuklin, V V

    2001-01-01

    In the Archangelskaya Bay (North Island of Novaya Zemlya), 25 specimens of sea birds have been collected: 5 kittiwakes, 5 murres, 5 little auks, 4 common eiders, 4 purple sandpipers, and 2 glaucous gulls. Following numbers of helminth parasite species have been recovered in this material: trematodes--1, cestodes--5, proboscic worms--2, and nematodes--2 species. The description of morphological characters of Anomotaenia micracantha micracantha (Cestoda: Dilepididae) from the kittiwake is given. The dependence of helminth fauna composition on the character of bird's feeding is traced. Differences in the infection with parasites of gulls and auks habitating the Archangelskaya Bay are revealed. Data on a life cycle of parasites found and ways of their circulation in the ecosystems of the Barents Sea are given. As for Triaenophorus erostris, which was indicated for gulls of the Barents Sea by Belopolskaya (1952), Galkin e. a. (1994) and Galaktionov e. a. (1997) as a common parasite, it was absent both in the material collected by Markov (1941) and in our material. PMID:11548578

  8. Satellite Tracking on the Flyways of Brown-Headed Gulls and Their Potential Role in the Spread of Highly Pathogenic Avian Influenza H5N1 Virus

    PubMed Central

    Ratanakorn, Parntep; Wiratsudakul, Anuwat; Wiriyarat, Witthawat; Eiamampai, Krairat; Farmer, Adrian H.; Webster, Robert G.; Chaichoune, Kridsada; Suwanpakdee, Sarin; Pothieng, Duangrat; Puthavathana, Pilaipan

    2012-01-01

    Brown-headed gulls (Larus brunnicephalus), winter visitors of Thailand, were tracked by satellite telemetry during 2008–2011 for investigating their roles in the highly pathogenic avian influenza (HPAI) H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam) affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1–2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak. PMID:23209623

  9. Z .ISPRS Journal of Photogrammetry & Remote Sensing 54 1999 123129 Scanning laser mapping of the coastal zone: the SHOALS system

    E-print Network

    Lefsky, Michael

    Z .ISPRS Journal of Photogrammetry & Remote Sensing 54 1999 123­129 Scanning laser mapping Zbathymetry systems in operation: SHOALS Scan- ning Hydrographic Operational Airborne Lidar Sur- . Zvey , LADS An airborne lidar bathymeter uses lidar technol- ogy to measure water depths. A laser transmitterrre- ceiver

  10. Anim. Behav., 1996, 52, 885890 Mixed-species shoals and the maintenance of a sexualasexual mating system

    E-print Network

    Ryan, Michael J.

    shoals with P. mexicana, and in Texas with P. latipinna. Poecilia mexicana is known to be the maternal of the sexual­asexual complex of sailfin mollies, Poecilia latipinna, and Amazon mollies, P. formosa, depends Behaviour The Amazon molly, Poecilia formosa (Girard 1859), is an all-female species of fish of hybrid

  11. Evidence for Carbonate Compensation Depth Shoaling at the Paleocene-Eocene Thermal Maximum on Shatsky Rise, ODP Leg 198

    Microsoft Academic Search

    A. Brill; T. J. Bralower; T. McDowell; D. J. Thomas; R. Cottone; J. C. Zachos

    2002-01-01

    The Paleocene-Eocene Thermal Maximum (PETM) was a transient interval of global warming approximately 55 million years ago. The event is associated with a prominent carbon isotope excursion that can best be explained by rapid dissociation of methane hydrate. This massive release of methane in conjunction with its subsequent oxidation to carbon dioxide likely resulted in a shoaling of the lysocline

  12. The Shark Assemblage at French Frigate Shoals Atoll, Hawai`i: Species Composition, Abundance and Habitat Use

    Microsoft Academic Search

    Jonathan J. Dale; Austin M. Stankus; Michael S. Burns; Carl G. Meyer; Richard Unsworth

    2011-01-01

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total

  13. SHOALING OF SOLITARY WAVES ON PLANE BEACHES By S. T. Gr'dli,1Member, ASCE, R. Subramanya, 2

    E-print Network

    Grilli, Stéphan T.

    , beach erosion, and design of coastal structures used for beach protection. The shoaling, breaking in coastal regions and because solitary waves approximately model steep waves on beaches. Hav- ing for extreme design waves of coastal structures. Although nonlinearity very much increases for waves close

  14. Postsynaptic alpha 1- and alpha 2-adrenoceptors in the vascular system of the herring gull, Larus argentatus.

    PubMed

    Hermansson, L E; Johansson, P

    1986-11-01

    The nature of the vascular alpha-adrenoceptors has been studied in the herring gull, Larus argentatus. In the anaesthetized herring gull, both phenylephrine and clonidine elicited dose-dependent increases in arterial blood pressure. The alpha 1-adrenoceptor antagonist prazosin was a better antagonist of phenylephrine than were the alpha 2-adrenoceptor antagonists yohimbine and rauwolscine. Yohimbine and rauwolscine were better antagonists of clonidine than was prazosin. The maximum response to phenylephrine, but not clonidine, was lower in reserpine-treated birds, indicating that phenylephrine in high doses liberates endogenous catecholamines, which contribute to the effect. It is concluded that the herring gull possesses postsynaptic, vascular alpha-adrenoceptors, of both the alpha 1- and alpha 2-subtypes, similar to those found in mammals. PMID:2879594

  15. Postsynaptic alpha 1- and alpha 2-adrenoceptors in the vascular system of the herring gull, Larus argentatus.

    PubMed Central

    Hermansson, L. E.; Johansson, P.

    1986-01-01

    The nature of the vascular alpha-adrenoceptors has been studied in the herring gull, Larus argentatus. In the anaesthetized herring gull, both phenylephrine and clonidine elicited dose-dependent increases in arterial blood pressure. The alpha 1-adrenoceptor antagonist prazosin was a better antagonist of phenylephrine than were the alpha 2-adrenoceptor antagonists yohimbine and rauwolscine. Yohimbine and rauwolscine were better antagonists of clonidine than was prazosin. The maximum response to phenylephrine, but not clonidine, was lower in reserpine-treated birds, indicating that phenylephrine in high doses liberates endogenous catecholamines, which contribute to the effect. It is concluded that the herring gull possesses postsynaptic, vascular alpha-adrenoceptors, of both the alpha 1- and alpha 2-subtypes, similar to those found in mammals. PMID:2879594

  16. Monitoring organic contaminants in eggs of glaucous and glaucous-winged gulls (Larus hyperboreus and Larus glaucescens) from Alaska.

    PubMed

    Vander Pol, Stacy S; Becker, Paul R; Ellisor, Michael B; Moors, Amanda J; Pugh, Rebecca S; Roseneau, David G

    2009-03-01

    Gull eggs have been used to monitor contaminants in many parts of the world. The Seabird Tissue Archival and Monitoring Project (STAMP) is a long-term program designed to track trends in pollutants in northern marine environments using seabird eggs. Glaucous and glaucous-winged gull (Larus hyperboreus and Larus glaucescens) eggs collected in 2005 from seven Alaskan colonies were analyzed for organic contaminants. Concentrations ranged from below detection limits to 322 ng g(-1) wet mass in one egg for 4,4'-DDE and differed among the samples collected in the Gulf of Alaska and Bering and Chukchi Seas. Chick growth and survival rates may be affected by the contaminant levels found in the eggs, but the eggs should be safe for human consumption if they are eaten in small quantities. STAMP plans to continue collecting and banking gull eggs for future real-time and retrospective analyses. PMID:19110348

  17. Genetic Markers for Rapid PCR-Based Identification of Gull, Canada Goose, Duck, and Chicken Fecal Contamination in Water

    PubMed Central

    Green, Hyatt C.; Dick, Linda K.; Gilpin, Brent; Samadpour, Mansour

    2012-01-01

    Avian feces contaminate waterways but contribute fewer human pathogens than human sources. Rapid identification and quantification of avian contamination would therefore be useful to prevent overestimation of human health risk. We used subtractive hybridization of PCR-amplified gull fecal 16S RNA genes to identify avian-specific fecal rRNA gene sequences. The subtracters were rRNA genes amplified from human, dog, cat, cow, and pig feces. Recovered sequences were related to Enterobacteriaceae (47%), Helicobacter (26%), Catellicoccus (11%), Fusobacterium (11%), and Campylobacter (5%). Three PCR assays, designated GFB, GFC, and GFD, were based on recovered sequence fragments. Quantitative PCR assays for GFC and GFD were developed using SYBR green. GFC detected down to 0.1 mg gull feces/100 ml (corresponding to 2 gull enterococci most probable number [MPN]/100 ml). GFD detected down to 0.1 mg chicken feces/100 ml (corresponding to 13 Escherichia coli MPN/100 ml). GFB and GFC were 97% and 94% specific to gulls, respectively. GFC cross-reacted with 35% of sheep samples but occurred at about 100,000 times lower concentrations in sheep. GFD was 100% avian specific and occurred in gulls, geese, chickens, and ducks. In the United States, Canada, and New Zealand, the three markers differed in their geographic distributions but were found across the range tested. These assays detected four important bird groups contributing to fecal contamination of waterways: gulls, geese, ducks, and chickens. Marker distributions across North America and in New Zealand suggest that they will have broad applicability in other parts of the world as well. PMID:22081573

  18. Developmental lead exposure disturbs expression of synaptic neural cell adhesion molecules in herring gull brains.

    PubMed

    Dey, P M; Burger, J; Gochfeld, M; Reuhl, K R

    2000-05-01

    Neurobehavioral testing of herring gull chicks (Larus argentatus) in both laboratory and field studies indicates that lead exposure during critical periods of development causes neurological deficits that may compromise survival in the wild. Accumulating evidence suggests that lead impairs neurodevelopment, in part, by altering the expression of cell adhesion molecules (CAMs) responsible for the proper formation and maintenance of neural structure and synaptic function. We examined the adhesion molecules NCAM, L1, and N-cadherin in gull brains to determine whether these CAMs are altered by lead exposure and might serve as markers of developmental neurotoxicity. One-day-old chicks were collected from nesting colonies and were laboratory housed. On post-hatching day (PHD) 2, chicks were given 100 mg/kg lead acetate or saline (intraperitoneally). Birds were killed on PHD 34, 44, or 55 (blood-lead levels averaged 27.4, 20.8, and 19.5 microg/dl, respectively). Brains were removed and stored at -70 degrees C until analysis. Expression of CAMs was determined in synaptosomal preparations by Western blotting and the activity of NCAM-associated sialyltransferase (ST) was determined in purified whole brain golgi apparatus. Elevation in synaptosomal polysialylated NCAM expression and a significant increase in golgi ST activity was observed in lead-treated animals at PHD 34. Reductions in synaptosomal N-cadherin were observed at PHD 34 and 44, while L1 expression appeared unaffected by lead at any time-point. By 55 days post-hatching, no differences in N-cadherin expression, polysialylated NCAM expression or NCAM-associated ST activity were seen in lead-treated animals as compared with age-matched control animals. Lead-induced disruption of CAM expression during early neurodevelopment may contribute to behavioral deficits observed in herring gulls in both the laboratory and the field, and may serve as a marker for heavy metal exposure during postnatal development. PMID:10814846

  19. Hybridization among Arctic white-headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Chesser, R. Terry; Bell, Douglas A.; Dove, Carla J.

    2012-01-01

    We studied the influence of glacial oscillations on the genetic structure of seven species of white-headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice-free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (FST= 0.129), introns (?ST= 0.185), and mtDNA control region (?ST= 0.461), with among-group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among-group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger t estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white-headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species-specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white-headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed.

  20. Hybridization among Arctic white-headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene.

    PubMed

    Sonsthagen, Sarah A; Chesser, R Terry; Bell, Douglas A; Dove, Carla J

    2012-06-01

    We studied the influence of glacial oscillations on the genetic structure of seven species of white-headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice-free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (F(ST)= 0.129), introns (?(ST)= 0.185), and mtDNA control region (?(ST)= 0.461), with among-group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among-group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger ? estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white-headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species-specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white-headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed. PMID:22833800

  1. Hybridization among Arctic white-headed gulls (Larus spp.) obscures the genetic legacy of the Pleistocene

    PubMed Central

    Sonsthagen, Sarah A; Chesser, R Terry; Bell, Douglas A; Dove, Carla J

    2012-01-01

    We studied the influence of glacial oscillations on the genetic structure of seven species of white-headed gull that breed at high latitudes (Larus argentatus, L. canus, L. glaucescens, L. glaucoides, L. hyperboreus, L. schistisagus, and L. thayeri). We evaluated localities hypothesized as ice-free areas or glacial refugia in other Arctic vertebrates using molecular data from 11 microsatellite loci, mitochondrial DNA (mtDNA) control region, and six nuclear introns for 32 populations across the Holarctic. Moderate levels of genetic structure were observed for microsatellites (FST= 0.129), introns (?ST= 0.185), and mtDNA control region (?ST= 0.461), with among-group variation maximized when populations were grouped based on subspecific classification. Two haplotype and at least two allele groups were observed across all loci. However, no haplotype/allele group was composed solely of individuals of a single species, a pattern consistent with recent divergence. Furthermore, northernmost populations were not well differentiated and among-group variation was maximized when L. argentatus and L. hyberboreus populations were grouped by locality rather than species, indicating recent hybridization. Four populations are located in putative Pleistocene glacial refugia and had larger ? estimates than the other 28 populations. However, we were unable to substantiate these putative refugia using coalescent theory, as all populations had genetic signatures of stability based on mtDNA. The extent of haplotype and allele sharing among Arctic white-headed gull species is noteworthy. Studies of other Arctic taxa have generally revealed species-specific clusters as well as genetic structure within species, usually correlated with geography. Aspects of white-headed gull behavioral biology, such as colonization ability and propensity to hybridize, as well as their recent evolutionary history, have likely played a large role in the limited genetic structure observed. PMID:22833800

  2. The breeding ecology of sea birds on Monito Island, Puerto Rico

    USGS Publications Warehouse

    Kepler, C.B.

    1978-01-01

    Monito Island, a 15-ha plateau surrounded by steep undercut cliffs, lies halfway between Puerto Rico and the Dominican Republic. Seven of the 9 sea birds are known to breed, and 2 (Blue-faced Booby and Laughing Gull) are here recorded as breeders in Puerto Rico for the first time. The Pelecaniformes are represented by 5 species, the White-tailed Tropicbird, the 3 pan-tropical boobies, and the Magnificent Frigatebird. The boobies all have long but annual breeding seasons, from fall through spring, showing a distinct breeding hiatus in the hot summer months, although some late-nesters may care for chicks during this period. The Magnificent Frigatebird has the most synchronous breeding, with a laying peak from late October to early December, when 70% of the population lay eggs. Four larids (Laughing Gull, Bridled Tern, Sooty Tern, and Brown Noddy) are summer residents vacating the island in August-September, and returning again in March-April. In general, they nest during the pelecaniform non-breeding season. The sea birds show a great range in nest site preference, with little overlap among them. Their diversity results from a combination of isolation, rugged cliffs, and the structural diversity of Monito Island. Although currently one of the outstanding sea bird colonies in the West Indies, Monito is threatened, and the colonies could be lost unless they are legally protected.

  3. Comparison of lead levels in bone, feathers, and liver of herring gull chicks (Larus argentatus).

    PubMed

    Burger, J; Reilly, S M; Gochfeld, M

    1992-02-01

    Bone, feathers, and liver were analyzed for lead in herring gull chicks (Larus argentatus) of two different ages. The highest levels were found in the bone, evidence of chronic exposure. No differences were found within the bones. Differences occurred between different bones, with the ribs having twice the amount of lead than any other bone. These studies indicate that type of bone affects lead levels; thus researchers should clearly state which parts of which bones are examined. It is also suggested that for humans consistent location should be used for analysis by in vivo X-ray fluorescence. PMID:1574517

  4. Vigilance and feeding behaviour in large feeding flocks of laughing gulls, Larus atricilla, on Delaware Bay

    NASA Astrophysics Data System (ADS)

    Burger, Joanna; Gochfeld, Michael

    1991-02-01

    Laughing gulls ( Larus atricilla) forage on horseshoe crab ( Limulus polyphemus) eggs during May in Delaware Bay each year. They feed in dense flocks, and foraging rates vary with vigilance, bird density, number of steps and location in the flock, whereas time devoted to vigilance is explained by number of steps, density, location and feeding rates. The time devoted to vigilance decreases with increasing density, increasing foraging rates and decreasing aggression. Birds foraging on the edge of flocks take fewer pecks and more steps, and devote more time to vigilance than those in the intermediate or central parts of a flock.

  5. Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas

    USGS Publications Warehouse

    Hicks, D.W.; Onuf, C.P.; Tunnell, J.W.

    1998-01-01

    Effects of a severe freeze on the shoal grass, Halodule wrightii, were documented through analysis of temporal and spatial trends in below-ground biomass. The coincidence of the second lowest temperature (-10.6??C) in 107 years of record, 56 consecutive hours below freezing, high winds and extremely low water levels exposed the Laguna Madre, TX, to the most severe cold stress in over a century. H. wrightii tolerated this extreme freeze event. Annual pre- and post-freeze surveys indicated that below-ground biomass estimated from volume was Unaffected by the freeze event. Nor was there any post-freeze change in biomass among intertidal sites directly exposed to freezing air temperatures relative to subtidal sites which remained submerged during the freezing period.

  6. Groundwater Model Validation for the Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    None

    2008-05-19

    Stoller has examined newly collected water level data in multiple wells at the Shoal site. On the basis of these data and information presented in the report, we are currently unable to confirm that the model is successfully validated. Most of our concerns regarding the model stem from two findings: (1) measured water level data do not provide clear evidence of a prevailing lateral flow direction; and (2) the groundwater flow system has been and continues to be in a transient state, which contrasts with assumed steady-state conditions in the model. The results of DRI's model validation efforts and observations made regarding water level behavior are discussed in the following sections. A summary of our conclusions and recommendations for a path forward are also provided in this letter report.

  7. 2008 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    None

    2009-03-01

    This report presents the 2008 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Subsurface Corrective Action Unit (CAU) 447 located in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 447 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 1996, as amended February 2008) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes proof of concept monitoring in support of site closure. This report summarizes investigation activities associated with CAU 447 that were conducted at the site during 2008. This is the second groundwater monitoring report prepared by LM for the PSA

  8. 2010 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447

    SciTech Connect

    None

    2011-02-01

    This report presents the 2010 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) Subsurface Corrective Action Unit (CAU) 447 in Churchill County, Nevada. Responsibility for the environmental site restoration of the PSA was transferred from the DOE Office of Environmental Management to LM on October 1, 2006. The environmental restoration process and corrective action strategy for CAU 447 are conducted in accordance with the Federal Facility Agreement and Consent Order (FFACO 1996, as amended March 2010) entered into by DOE, the U.S. Department of Defense, and the State of Nevada. The corrective action strategy for the site includes monitoring in support of site closure. This report summarizes the results from the groundwater monitoring program during fiscal year 2010.

  9. Consistent nonlinear deterministic and stochastic evolution equations for deep to shallow water wave shoaling

    NASA Astrophysics Data System (ADS)

    Vrecica, Teodor; Toledo, Yaron

    2015-04-01

    One-dimensional deterministic and stochastic evolution equations are derived for the dispersive nonlinear waves while taking dissipation of energy into account. The deterministic nonlinear evolution equations are formulated using operational calculus by following the approach of Bredmose et al. (2005). Their formulation is extended to include the linear and nonlinear effects of wave dissipation due to friction and breaking. The resulting equation set describes the linear evolution of the velocity potential for each wave harmonic coupled by quadratic nonlinear terms. These terms describe the nonlinear interactions between triads of waves, which represent the leading-order nonlinear effects in the near-shore region. The equations are translated to the amplitudes of the surface elevation by using the approach of Agnon and Sheremet (1997) with the correction of Eldeberky and Madsen (1999). The only current possibility for calculating the surface gravity wave field over large domains is by using stochastic wave evolution models. Hence, the above deterministic model is formulated as a stochastic one using the method of Agnon and Sheremet (1997) with two types of stochastic closure relations (Benney and Saffman's, 1966, and Hollway's, 1980). These formulations cannot be applied to the common wave forecasting models without further manipulation, as they include a non-local wave shoaling coefficients (i.e., ones that require integration along the wave rays). Therefore, a localization method was applied (see Stiassnie and Drimer, 2006, and Toledo and Agnon, 2012). This process essentially extracts the local terms that constitute the mean nonlinear energy transfer while discarding the remaining oscillatory terms, which transfer energy back and forth. One of the main findings of this work is the understanding that the approximated non-local coefficients behave in two essentially different manners. In intermediate water depths these coefficients indeed consist of rapidly oscillating terms, but as the water depth becomes shallow they change to an exponential growth (or decay) behavior. Hence, the formerly used localization technique cannot be justified for the shallow water region. A new formulation is devised for the localization in shallow water, it approximates the nonlinear non-local shoaling coefficient in shallow water and matches it to the one fitting to the intermediate water region. This allows the model behavior to be consistent from deep water to intermediate depths and up to the shallow water regime. Various simulations of the model were performed for the cases of intermediate, and shallow water, overall the model was found to give good results in both shallow and intermediate water depths. The essential difference between the shallow and intermediate nonlinear shoaling physics is explained via the dominating class III Bragg resonances phenomenon. By inspecting the resonance conditions and the nature of the dispersion relation, it is shown that unlike in the intermediate water regime, in shallow water depths the formation of resonant interactions is possible without taking into account bottom components. References Agnon, Y. & Sheremet, A. 1997 Stochastic nonlinear shoaling of directional spectra. J. Fluid Mech. 345, 79-99. Benney, D. J. & Saffman, P. G. 1966 Nonlinear interactions of random waves. Proc. R. Soc. Lond. A 289, 301-321. Bredmose, H., Agnon, Y., Madsen, P.A. & Schaffer, H.A. 2005 Wave transformation models with exact second-order transfer. European J. of Mech. - B/Fluids 24 (6), 659-682. Eldeberky, Y. & Madsen, P. A. 1999 Deterministic and stochastic evolution equations for fully dispersive and weakly nonlinear waves. Coastal Engineering 38, 1-24. Kaihatu, J. M. & Kirby, J. T. 1995 Nonlinear transformation of waves in infinite water depth. Phys. Fluids 8, 175-188. Holloway, G. 1980 Oceanic internal waves are not weak waves. J. Phys. Oceanogr. 10, 906-914. Stiassnie, M. & Drimer, N. 2006 Prediction of long forcing waves for harbor agitation studies. J. of waterways, port, coastal and oce

  10. Nihoa Island

    NSDL National Science Digital Library

    2007-08-09

    This video segment adapted from the NOW-RAMP 2002 Expedition documents a research expedition to Nihoa Island. It showcases Nihoa's unique birds and plants, the threat posed by invading grasshoppers, and restoration efforts.

  11. Rebecca shoal barrier reef complex of Gulfian and Paleocene age - onshore and offshore Florida

    SciTech Connect

    Winston, G.O.

    1989-03-01

    Surrounding the Florida Peninsula and the offshore portion of the South Florida basin is a 1300-mi long dolomite barrier reef complex that occupies a 3800-ft composite interval spanning most of the Gulfian and Paleocene. Forty-four wells have penetrated various aspects of this complex. Growth began with the Card Sound facies (some 1400 ft thick) in the lower Gulfian, shortly after the end of the Early Cretaceous. This facies is present in only two wells, 4 mi apart on Key Largo. The appearance of the Rebecca Shoal reef in the earliest Gulfian indicates that the Florida Straits were then present, as deep water would have been necessary to support a growing reef of this magnitude. During the late Gulfian, the reef (Plantation equivalent) expanded northward along the East Coast and westward along the Keys. The width now was over 6 mi. By the beginning of the Paleocene, the reef (Tavernier facies) had completely surrounded the peninsula, resulting in the deposition of the Cedar Keys dolomite-anhydrite lagoonal facies. The width of the complex was now as much as 20 mi. At the close of the Paleocene, the Rebecca Shoals reef ended abruptly. It was overlain by an orange/brown anhedral dolomite characteristic of the basal Eocene. The lithology of the outer region of the reef complex is characterized by a light-colored, porous, fine to medium crystalline euhedral dolomite. Large cavities, including a 60-ft cavern, have been reported. Two core samples show a taluslike rubble texture with vug porosity between the square-sided fragments. Behind the Tavernier reef, this facies is gradually replaced by nonporous anhedral and cryptocrystalline dolomite. Farther lagoonward, these three lithologies become interbedded with typical Cedar keys, a very fine microcrystalline to microcrystalline dolomite.

  12. Analysis of submarine sand wave imaging by SAR in Taiwan shoal

    NASA Astrophysics Data System (ADS)

    Fan, Kaiguo; Huang, Weigen; Chen, Peng; Fu, Bin; Yu, Xingxiu; Chang, Junfang

    2011-11-01

    In this paper, submarine sand wave imaging by SAR in Taiwan shoal and their relationships with sea surface wind and sea surface current are discussed. A total of 69 synthetic aperture radar (SAR) images over 11 years between 1996 and 2006 are collected and 496 profiles of sand wave SAR images are used for the observations of sand wave SAR images. The sea surface wind estimated from NCEP/QSCAT blended wind data and the sea surface current calculated form highfrequency (HF) radar system are utilized for the study on the observations of sand wave SAR images with the wind speed and current speed. The results show submarine sand waves in Taiwan Shoal are mainly distributed from 117.75°E to 118.70°E and 22.7°N to 23.35°N with a high percent of 72.2. About 91% of sand waves are observed by SAR under wind speed of 9 m/s while only 6% of sand waves are imaged above wind speed of 10 m/s. And under the adverse wind direction, the observed sand wave reaches its maximum, while the crosswind has its minimum. These support that low and middle wind speed and adverse wind direction are favorable for SAR imaging submarine sand waves, high wind speed and crosswind are unfavorable. The observations of sand wave SAR images reach its seasonal maximum with a percentage of 49 in summer and have its minimum in autumn with 8%, while spring and winter has percentage of 20 and 23 respectively. The comparisons for monthly mean sea surface wind speed and monthly mean sea surface current speed with observed sand waves also shows strong relationships, which are lower sea surface wind speeds and higher sea surface current speed, the higher probability of sand waves observed by SAR. This may indicate that the higher observation of the sand waves by SAR is partly due to wind speed and current speed.

  13. Turbulence and mixing generated by internal waves shoaling on a barrier reef.

    NASA Astrophysics Data System (ADS)

    Davis, K. A.; Monismith, S. G.

    2008-12-01

    Results are presented from an observational study of the turbulent bottom boundary layer on the outer Southeast Florida shelf in July and August 2005. ADCPs and ADVs deployed at 15 m on Conch Reef measured mean and turbulent velocities. Turbulence in the reef bottom boundary layer is highly variable in time and is modified by near bed flow, shear, and stratification driven by shoaling internal waves. In the absence of internal waves on the shelf, currents from 1 to 5 meters above the bed are well described by a logarithmic profile and turbulent dissipation measured 0.6 to 3.0 meters above the bed agrees with classic bottom boundary layer scaling. We examine turbulence in the bottom boundary layer during a typical internal wave event and show that internal waves can induce significant increases in near-bed flow speed, shear, dissipation, and turbulent scalar diffusivity, K?. Estimates of flux Richardson number, calculated directly from measurements of dissipation and buoyancy flux, support the dependence of Rf on Frt and on turbulent intensity, ?/?N2, relationships that have been previously shown in laboratory and numerical work. Results from this study suggest that for reef communities exposed to continental shelf and slope processes, internal waves may play an important role in mass transfer to benthic organisms. In addition to the episodic onshore transport of cool, subthermocline water masses, with elevated nutrient concentrations, we have shown that the bottom-intensified currents from shoaling internal waves can increase turbulent dissipation and mixing in the reef bottom boundary layer.

  14. Fluid Management Plan for Corrective Action Unit 447: Project Shoal Area, Subsurface, Nevada, Rev. No.: 1

    SciTech Connect

    Findlay, Rick

    2006-01-01

    The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) initiated the Offsites Project to characterize the risk posed to human health and the environment as a result of testing at formerly used nuclear sites in Alaska, Colorado, Mississippi, Nevada, and New Mexico. The scope of this Fluid Management Plan (FMP) is to support the subsurface investigation at the Project Shoal Area (PSA) Corrective Action Unit (CAU) 447, Shoal - Subsurface, Nevada, in accordance with the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996). Corrective Action Unit 447 is located in the Sand Spring Range, south of Highway 50, about 39 miles southeast of Fallon, Nevada. (Figure 1-1). This FMP will be used at the PSA in lieu of an individual discharge permit for each well or a general water pollution control permit for management of all fluids produced during the drilling, construction, development, testing, experimentation, and/or sampling of wells conducted by the Offsites Project. The FMP provides guidance for the management of fluids generated during investigation activities and provides the standards by which fluids may be discharged on site. Although the Nevada Division of Environmental Protection (NDEP), Bureau of Federal Facilities (BoFF) is not a signatory to this FMP, it is involved in the negotiation of the contents of this plan and approves the conditions contained within. The major elements of this FMP include: (1) establishment of a well-site operations strategy; (2) site design/layout; (3) monitoring of contamination indicators (monitoring program); (4) sump characterization (sump sampling program); (5) fluid management decision criteria and fluid disposition; and (6) reporting requirements.

  15. Reproductive success of the Black-crowned Night Heron at Alcatraz Island, San Francisco Bay, California, 1990-2002

    USGS Publications Warehouse

    Hothem, R.L.; Hatch, D.

    2004-01-01

    Nesting chronology, habitat use, subcolony use, and hatchability were documented for the Black-crowned Night Heron (Nycticorax nycticorax) nesting at Alcatraz Island, San Francisco Bav, California during 1990-2002. Reproductive success was estimated using the Mayfield method and compared among years. Totals of monitored nests per year ranged from 68 in 2001 to 341 in 1996, with a trend of declining numbers since 1996. An increase in numbers of the Western Gull (Larus occidentalis), the Black-crowned Night Heron's primary competitor, occurred during the same period. Overall reproductive success of the Black-crowned Night Heron at Alcatraz Island was below the 13-year average of 56.4% since 1996. During the study, the average number of chicks fledged per nest each year ranged from 0.46 to 1.27, which is less than the two chicks per nest suggested as a requirement for a sustained population. Embryos in five of 187 failed Black-crowned Night Heron eggs were deformed. In 1990 and 1991, eggs were analyzed for a wide range of contaminants, but none appeared to be sufficiently elevated to have caused the observed deformities. Based on these relatively low levels of contaminants, a high hatchability rate (94.5%), and relatively low levels of embryotoxicity, contaminants did not appear to significantly affect Black-crowned Night Heron reproduction at Alcatraz Island. However, predation by the Common Raven (Corvus corax) and Western Gull, interspecific competition with the Western Gull, habitat deterioration, and possible human disturbance are likely factors contributing to the decline in Black-crowned Night Heron reproductive success on Alcatraz Island in recent years.

  16. Development and application of a quantitative PCR assay targeting Catellicoccus marimammalium for assessing gull-associated fecal contamination at Lake Erie beaches.

    PubMed

    Lee, Cheonghoon; Marion, Jason W; Lee, Jiyoung

    2013-06-01

    Gulls represent one of the major fecal contamination sources responsible for the degradation of water quality at Lake Erie beaches. For assessing gull-associated fecal contamination, a real-time quantitative PCR assay (qPCR) targeting 16S rRNA gene sequences from Catellicoccus marimammalium, which are abundant in gull feces, was developed and evaluated by comparing assay results with beach survey data that included gull counting, and quantifying densities of Escherichia coli and human-associated fecal markers at two Lake Erie beaches. In evaluating the specificity and sensitivity of the qPCR assay with animal and wastewater samples, C. marimammalium was detected in most gull fecal samples (80.7%), some chicken fecal samples (24.1%), but was not readily detected from other fecal samples of animals and humans, and wastewater. Among 66 Lake Erie water samples collected in 2010, C. marimammalium was frequently detected from Villa Angela (36.4%) and Headlands beaches (57.6%). C. marimammalium densities were not associated with E. coli densities or sanitary survey data. E. coli counts were likely driven by other sources, such as human, rather than gulls at the study sites. The presumption that human contamination influenced E. coli counts was supported by more frequent detection of the human-specific Bacteroides gyrB marker (gyrB) at Villa Angela (33.3%) than Headlands (6.1%). Since E. coli may not be an effective indicator for assessing gull-related fecal contamination at these beaches, where contamination sources are mixed, our novel qPCR assay can be useful for understanding fecal source contributions from gulls not explained by gull abundance or E. coli densities. PMID:23542477

  17. Low-frequency target strength and abundance of shoaling Atlantic herring (Clupea harengus) in the Gulf of Maine during the Ocean Acoustic Waveguide Remote Sensing 2006 Experiment

    E-print Network

    Gong, Zheng

    2010-01-01

    The low-frequency target strength of shoaling Atlantic herring (Clupea harengus) in the Gulf of Maine during Autumn 2006 spawning season is estimated from experimental data acquired simultaneously at multiple frequencies ...

  18. Behavioral effects of early postnatal lead exposure in herring gull (Larus argentatus) chicks.

    PubMed

    Burger, J

    1990-01-01

    Lead exposure early in life affects behavioral and intellectual development in humans. In this paper, I use the herring gull, Larus argentatus, as an animal model to examine effects of lead exposure on early development. Like humans, birds rely mainly on visual and vocal, rather than olfactory, modes of communication. Each of 24 one-day-old herring gull chicks was randomly assigned to one of three treatment groups to receive a lead nitrate solution at a concentration of 0.0, 0.1 and 0.2 mg/g. The control dose was an equal volume of sterile saline. The trios were not siblings, but were matched by weight. Behavioral tests were performed either daily, every two to five days, or at the end of the experiment (45 days posthatching), depending on the nature of the experiment. The behavioral tests examined locomotion, balance, righting response, begging, recognition, thermoregulation and visual cliff. Although on most days, begging behavior, balance and righting response did not differ significantly, over the 45 days of the experiment control birds performed better on more days than the lead-injected birds. Balance was disturbed by lead-injection for the first six days following injection. Individual recognition developed by day 5 in control birds, by day 10 for 0.1 Pb mg/g birds, and by day 14 for 0.2 Pb mg/g birds. Depth perception and thermoregulation behavior were also adversely affected by lead. PMID:2315373

  19. Heavy metals in Franklin`s gull tissues: Age and tissue differences

    SciTech Connect

    Burger, J. [Rutgers Univ., Piscataway, NJ (United States); Gochfeld, M. [Rutgers Univ., Piscataway, NJ (United States). Environmental and Occupational Health Sciences Inst.]|[UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    1999-04-01

    The authors examined the concentrations of lead, cadmium, chromium, mercury, manganese, and selenium in feathers, liver, kidney, heart, brain, and breast muscle of Franklin`s gulls (Larus pipixcan) nesting in northwestern Minnesota, USA, in 1994. Between 16% (chromium) and 71% (selenium, manganese) of the variation in metal concentrations was explained by tissue and age, except for selenium and arsenic, which were only explained by tissue. Of 35 possible differences (seven metals in five tissues), 24 significant age-related differences were found in Franklin`s gulls, with young generally having lower concentrations of metals in all of their tissues than adults. A notable exception was the liver; young had significantly higher concentrations of selenium, chromium, manganese, and arsenic than did adults. Three notable findings were the following: young had significantly higher concentrations of selenium, chromium, manganese, and arsenic in their liver than did adults; young had 30 times as much chromium in the liver than adults; and adults had greatly elevated concentrations of cadmium in feathers, kidney, and liver.

  20. Perfluoroalkyl and polyfluoroalkyl substances in entire clutches of Audouin's gulls from the Ebro Delta.

    PubMed

    Vicente, Joana; Sanpera, Carola; García-Tarrasón, Manuel; Pérez, Alba; Lacorte, Silvia

    2015-01-01

    The aim of the present study was to determine the distribution of per- and polyfluoroalkyl substances (PFASs) in three-egg clutches of Audouin's gull (Larus audouinii) breeding in Ebro Delta's colony according to the laying order (a, b and c eggs). Five PFASs were analyzed in 30 eggs (yolk and albumen separately), corresponding to 10 three-egg clutches. Carbon and nitrogen stable isotopes were measured as dietary tracers. PFASs were not detected in albumen. In egg yolks, perfluorooctane sulfonate (PFOS) was the main compound detected followed by perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHS) and perfluorooctanoic acid (PFOA). Perfluorooctane sulfonate (PFBS) was not detected. Mean ?PFASs for a-eggs was of 236±57 ng g(-1) yolk wet weight (ww), for b-eggs was of 140±56 ng g(-1) yolk ww and for c-eggs, 133±54 ng g(-1) yolk ww. PFOS concentration decreased according to the laying order of the eggs, showing significant differences between consecutive eggs. In addition, significant correlation (rs2=0.7-0.9) was observed for PFOS concentration within the eggs from the same clutch. No relationship was found between PFOS levels and stable isotopes signatures. Capsule: In Audouin gull's eggs, PFOS was the main PFASs detected and its concentration decreased according to the laying sequence. PMID:24815900

  1. Low frequency of extra-pair paternity in Common Gulls ( Larus canus ) as revealed by DNA fingerprinting

    Microsoft Academic Search

    Monika Bukaeifiska; Dariusz Bukacifiski; Jörg Thomas Epplen; Klaus Peter Sauer; Thomas Lubjuhn

    1998-01-01

    Summary During the last decade, the mating systems of many bird species have been analysed using molecular genetic methods. Most of these studies were performed on Passeriformes while Non-Passeriformes were rarely investigated. To fill this gap, we analysed blood samples of 24 Common Gull (Larus canus) families from two Polish colonies using DNA fingerprinting. A total of 55 of 56

  2. The Toxic Effects of Multiple Persistent Organic Pollutant Exposures on the Post-Hatch Immunity Maturation of Glaucous Gulls

    Microsoft Academic Search

    Kjetil Sagerup; Hans Jørgen S. Larsen; Janneche Utne Skaare; Grethe M. Johansen; Geir Wing Gabrielsen

    2009-01-01

    This study tested whether the immune system of the glaucous gull (Larus hyperboreus) chicks became affected by existing environmental contaminants. An experimental group was given food that mimicked the natural contaminant mixture found in food from the North Atlantic marine environment, while the control group was given the equivalent of nearly clean food. All chicks were immunized with herpes virus

  3. Isolation, Cryopreservation, and Mitogenesis of Peripheral Blood Lymphocytes from Chickens ( Gallus domesticus ) and Wild Herring Gulls ( Larus argentatus )

    Microsoft Academic Search

    E. T. Lavoie; K. A. Grasman

    2005-01-01

    Monitoring the toxicity of environmental contaminants on the physiologic function of wild birds often includes measures of immune function. The purpose of this study was to apply methods of isolation, cryopreservation, and cell culture of chicken lymphocytes to blood samples from herring gulls, which are a sentinel species for biomonitoring studies in the Great Lakes and northern North America. Slow-spin

  4. Ross's Gulls (Rhodostethia rosea) Breeding in Greenland: A Review, with Special Emphasis on Records from 1979 to 2007

    Microsoft Academic Search

    CARSTEN EGEVANG; DAVID BOERTMANN

    This review summarizes breeding records of Ross's gull in Greenland with special emphasis on the period between 1979 and 2007. The review comprises both previously published records (including some published only in Danish) and unpublished reports and breeding records from 2004 and 2006. The majority of the Greenland breeding records fall into two geographically isolated areas that differ in habitat

  5. Organochlorine-associated immunosuppression in prefledgling Caspian terns and herring gulls from the Great Lakes: an ecoepidemiological study.

    PubMed Central

    Grasman, K A; Fox, G A; Scanlon, P F; Ludwig, J P

    1996-01-01

    The objectives of study were to determine whether contaminant-associated immunosuppression occurs in prefledgling herring gulls and Caspian terns from the Great Lakes and to evaluate immunological biomarkers for monitoring health effects in wild birds. During 1992 to 1994, immunological responses and related variables were measured in prefledgling chicks at colonies distributed across a broad gradient of organochlorine contamination (primarily polychlorinated biphenyls), which was measured in eggs. The phytohemagglutinin skin test was used to assess T-lymphocyte function. In both species, there was a strong exposure-response relationship between organochlorines and suppressed T-cell-mediated immunity. Suppression was most severe (30-45%) in colonies in Lake Ontario (1992) and Saginaw Bay (1992-1994) for both species and in western Lake Erie (1992) for herring gulls. Both species exhibited biologically significant differences among sites in anti-sheep red blood cells antibody titers, but consistent exposure-response relationships with organochlorines were not observed. In Caspian terns and, to a lesser degree, in herring gulls, there was an exposure-response relationship between organochlorines and reduced plasma retinol (vitamin A). In 1992, altered White blood cell numbers were associated with elevated organochlorine concentrations in Caspian terns but not herring gulls. The immunological and hematological biomarkers used in this study revealed contaminant-associated health effects in wild birds. An epidemiological analysis strongly supported the hypothesis that suppression of T-cell-mediated immunity was associated with high perinatal exposure to persistent organochlorine contaminants. PMID:8880006

  6. Evidence of Weak Contaminant-Related Oxidative Stress in Glaucous Gulls (Larus hyperboreus) from the Canadian Arctic

    Microsoft Academic Search

    Mark Wayland; David J. Hoffman; Mark L. Mallory; Ray T. Alisauskas; Katherine R. Stebbins

    2010-01-01

    Environmental contaminants are transported over great distances to Arctic ecosystems, where they can accumulate in wildlife. Whether contaminant concentrations in wildlife are sufficient to produce adverse effects remains poorly understood. Exposure to contaminants elevates oxidative stress with possible fitness consequences. The glaucous gull (Larus hyperboreus), an Arctic top predator, was used as a bioindicator for investigating relationships between contaminant levels

  7. Flame retardants and methoxylated and hydroxylated polybrominated diphenyl ethers in two Norwegian Arctic top predators: glaucous gulls and polar bears.

    PubMed

    Verreault, Jonathan; Gabrielsen, Geir W; Chu, Shaogang; Muir, Derek C G; Andersen, Magnus; Hamaed, Ahmad; Letcher, Robert J

    2005-08-15

    The brominated flame retardants have been subject of a particular environmental focus in the Arctic. The present study investigated the congener patterns and levels of total hexabromocyclododecane (HBCD), polybrominated biphenyls, polybrominated diphenyl ethers (PBDEs), as well as methoxylated (MeO) and hydroxylated (OH) PBDEs in plasma samples of glaucous gulls (Larus hyperboreus) and polar bears (Ursus maritimus) from the Norwegian Arctic. The analyses revealed the presence of total HBCD (0.07-1.24 ng/g wet wt) and brominated biphenyl 101 (< 0.13-0.72 ng/g wet wt) in glaucous gull samples whereas these compounds were generally found at nondetectable or transient concentrations in polar bears. Sum (sigma) concentrations of the 12 PBDEs monitored in glaucous gulls (range: 8.23-67.5 ng/g wet wt) surpassed largely those of polar bears (range: 2.65-9.72 ng/g wet wt). Two higher brominated PBDEs, BDE183 and BDE209, were detected, and thus bioaccumulated to a limited degree, in glaucous gulls with concentrations ranging from < 0.03 to 0.43 ng/g wet wt and from < 0.05 to 0.33 ng/g wet wt, respectively. In polar bear plasma, BDE183 was < 0.04 ng/g wet wt for all animals, and BDE209 was only detected in 7% of the samples at concentrations up to 0.10 ng/g wet wt. Of the 15 MeO-PBDEs analyzed in plasma samples, 3-MeO-BDE47 was consistently dominant in glaucous gulls (sigmaMeO-PBDE: 0.30-4.30 ng/g wet wt) and polar bears (sigmaMeO-PBDE up to 0.17 ng/g wet wt), followed by 4'-MeO-BDE49 and 6-MeO-BDE47. The 3-OH-BDE47, 4'-OH-BDE49, and 6-OH-BDE47 congeners were also detected in glaucous gulls (sigmaOH-PBDE up to 1.05 ng/g wet wt), although in polar bears 4'-OH-BDE49 was the only congener quantifiable in 13% of the samples. The presence of MeO- and OH-PBDEs in plasma of both species suggests possible dietary uptake from naturally occurring sources (e.g., marine sponges and green algae), but also metabolically derived biotransformation of PBDEs such as BDE47 could be a contributing factor. Our findings suggest that there are dissimilar biochemical mechanisms involved in PCB and PBDE metabolism and accumulation/elimination and/or OH-PBDE accumulation and retention in glaucous gulls and polar bears. PMID:16173559

  8. Geographic variation in hematological variables in adult and prefledgling herring gulls (Larus argentatus) and possible associations with organochlorine exposure.

    PubMed

    Grasman, K A; Scanlon, P F; Fox, G A

    2000-02-01

    The objectives of this study were (1) to describe variation in hematological values found in adult and prefledgling herring gulls (Larus argentatus) over a large geographic area, (2) to investigate relationships between hematological variables and other physiological indices, and (3) to examine potential associations between exposure to organochlorines and hematological variables. During 1991-93, we sampled 160 breeding adult gulls from 13 colonies and 101 4-week-old gulls from 11 colonies. All colonies were in the Great Lakes ecosystem, except for two colonies on Lake Winnipeg and the Atlantic coast. The hematological values measured in this study were similar to published values for herring gulls and related species. Significant intersite differences were found in hematological variables. Sex had little or no influence on leukocyte variables. Adults had lower total leukocyte counts and higher heterophil to lymphocyte ratios than chicks. PCV was lower in adult females than males. In adults, total leukocyte and total heterophil numbers were negatively associated with liver activity of ethoxyresorufin-O-deethylase (EROD) and concentrations of highly carboxylated porphyrins (HCPs), two biomarkers of organochlorine exposure. Total leukocyte and total heterophil numbers were positively associated with liver concentrations of DDE (1, 1-dichloro-2,2-bis(p-chlorophenyl)ethylene), and total lymphocytes were associated positively with PCB (polychlorinated biphenyl) and HCP concentrations. The heterophil to lymphocyte ratio was negatively associated with liver EROD activity and HCPs. In chicks, there was a positive association between the heterophil to lymphocyte ratio and HG-TEQs (dioxin toxicity equivalents calculated using herring gull-specific equivalency factors). PCV was associated with some measures of contaminant exposure in adults and chicks. Additional research is needed to elucidate causal relationships between hematological indices and such factors as contaminants, disease, and nutrition. PMID:10629288

  9. Environmental complexity influences association network structure and network-based diffusion of foraging information in fish shoals.

    PubMed

    Webster, Mike M; Atton, Nicola; Hoppitt, William J E; Laland, Kevin N

    2013-02-01

    Socially transmitted information can significantly affect the ways in which animals interact with their environments. We used network-based diffusion analysis, a novel and powerful tool for exploring information transmission, to model the rate at which sticklebacks (Gasterosteus aculeatus) discovered prey patches, comparing shoals foraging in open and structured environments. We found that for groups in the open environment, individuals tended to recruit to both the prey patch and empty comparison patches at similar times, suggesting that patch discovery was not greatly affected by direct social transmission. In contrast, in structured environments we found strong evidence that information about prey patch location was socially transmitted and moreover that the pathway of information transmission followed the shoals' association network structures. Our findings highlight the importance of considering habitat structure when investigating the diffusion of information through populations and imply that association networks take on greater ecological significance in structured than open environments. PMID:23348777

  10. Polyphased dolomitization of a shoal-rimmed carbonate platform: example from the middle Turonian Bireno dolomites of central Tunisia

    Microsoft Academic Search

    Jamel Touir; Mohamed Soussi; Habib Troudi

    2009-01-01

    The middle Turonian Bireno carbonate platform of central Tunisia consists of a shoal-rimmed platform including at least three carbonate units deposited in inner to outer shelf depositional settings. The Bireno middle unit is dominantly composed of dolomites capped by a subaerial exposure surface correlative with the global SB 90.5Ma. Dolomitization occurred during a major sea-level fall which resulted in a

  11. Seasonal Timing of Bald Eagle Attendance and Influence on Activity Budgets of Glaucous-winged Gulls in Barkley Sound, British Columbia

    E-print Network

    (Haliaeetus leucocephalus) actively prey on Glaucous-winged Gulls and their offspring (Larus glaucescens-activity budget, vigi- lance. Waterbirds 29(4): 497-500, 2006 Bald Eagle (Haliaeetus leucocephalus) pop- ulations

  12. Short communication Henslow's swimming crab (Polybius henslowii) as an important food for yellow-legged gulls (Larus cachinnans) in NW Spain

    Microsoft Academic Search

    Ignacio Munilla

    An analysis of the contents of 2562 pellets sampled from 1987 to 1993 at breeding colonies and roosting sites showed that Henslow's swimming crabs (Polybius henslowii) are by far the most important marine prey for yellow-legged gulls (Larus cachinnans) on the coasts of Galicia (north-western Spain), occurring in 36.4% of pellets. The results also suggest that yellow-legged gulls in Galicia

  13. Recombinant transthyretin purification and competitive binding with organohalogen compounds in two gull species (Larus argentatus and Larus hyperboreus).

    PubMed

    Ucán-Marín, Francisco; Arukwe, Augustine; Mortensen, Anne; Gabrielsen, Geir W; Fox, Glen A; Letcher, Robert J

    2009-02-01

    Glaucous gulls (Larus hyperboreus) from Svalbard, Norway (marine), and herring gulls (Larus argentatus) from the Laurentian Great Lakes (freshwater) of North America are differentially exposed to persistent and bioaccumulative anthropogenic contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ether (PBDE) flame retardants and metabolic products. Such compounds can potentially perturb hormone transport via binding interactions with proteins such as transthyretin (TTR, prealbumin). In this present study, we isolated, cloned and sequenced TTR cDNA from the brain and liver of two species (herring and glaucous gull), which, to our knowledge, is the first report describing the TTR nucleic acid and amino acid sequences from any gull species. Identical TTR nucleotide and amino acid sequences were obtained from both gull species (liver and brain). Recombinant TTR (rTTR) was expressed and purified, and determined as a monomer of 18 kDa and homodimer of 36 kDa that putatively is comprised of the two protein monomers. Concentration dependent, competitive TTR-binding curves with each of the natural TTR ligands 3,5,3'-triiodothyronine (T(3)) and thyroxine (T(4)) were generated as well as by treatment with a range of concentrations (10(-3)-10(5)nM) of 2,2',3,4',5,5',6-heptaCB (CB187), 2,2',4,4'-tetrabromoDE (BDE47), and hydroxyl- (OH) and methoxyl (MeO)-containing analogs (i.e., 4-OH-CB187, 6-OH-BDE47, 4'-OH-BDE49, 4-MeO-CB187, and 6-MeO-BDE47). Relative to the nonsubstituted BDE47 and CB187 and their MeO-substituted analogs, the OH-substituted analogs all had lower K(i) and K(d) values, indicating greater affinity and more potent competitive binding to both T(3) and T(4). The OH-substitution position and/or the diphenyl ether substitution of the four bromine atoms resulted in more potent, greater affinity, and greater relative potency for 4'-OH-BDE49 relative to 6-OH-BDE47. CB187 was more comparable in binding potency and affinity to 4-OH-CB187, then was 6-OH-BDE47 and 4'-OH-BDE49 relative to BDE47 where the binding potency and affinity was several orders of magnitude greater for 6-OH-BDE47 and 4'-OH-BDE49. This indicated that the combination of the more thyroid hormone-like brominated diphenyl ether backbone (relative to the chlorinated biphenyl backbone), and in combination of having an OH-group, results in a more effective competitive ligand on gull TTR relative to both T(3) and T(4). Known circulating levels of 4-OH-CB187, 6-OH-BDE47, and 4'-OH-BDE49 in the plasma of free-ranging Svalbard glaucous gulls were comparable to the concentration of in vitro competitive potency of T(3) and T(4) with gull TTR. These results suggest that environmentally relevant and selected OH-containing PCB, and to a lesser extent PBDE congeners have the potential to be physiologically effective in these gull species via perturbation of T(4) and T(3) transport. PMID:19033396

  14. Growth, bioluminescence and shoal behavior hormetic responses to inorganic and/or organic chemicals: a review.

    PubMed

    Hashmi, Muhammad Zaffar; Naveedullah; Shen, Hui; Zhu, Shenhai; Yu, Chunna; Shen, Chaofeng

    2014-03-01

    A biphasic dose response, termed hormesis, is characterized by beneficial effects of a chemical at a low dose and harmful effects at a high dose. This biphasic dose response phenomenon has the potential to strongly alter toxicology in a broad range. The present review focuses on the progress of research into hormetic responses in terms of growth (in plants, birds, algae and humans), bioluminescence, and shoal behavior as end points. The paper describes how both inorganic and organic chemicals at a low dose show stimulatory responses while at higher doses are inhibitory. The article highlights how factors such as symbiosis, density-dependent factors, time, and contrasting environmental factors (availability of nutrients, temperature, light, etc.) affect both the range and amplitude of hormetic responses. Furthermore, the possible underlying mechanisms are also discussed and we suggest that, for every end point, different hormetic mechanisms may exist. The occurrences of varying interacting receptor systems or receptor systems affecting the assessment of hormesis for each endpoint are discussed. The present review suggests that a hormetic model should be adopted for toxicological evaluations instead of the older threshold and linear non-threshold models. PMID:24361513

  15. Identification of a xylose-containing cerebroside in the salt gland of the herring gull.

    PubMed

    Karlsson, K A; Samuelsson, B E; Steen, G O

    1972-03-01

    A pentose-containing cerebroside has been identified in the salt gland of the herring gull, using mass spectrometry of acetyl and trimethylsilyl derivatives. A detailed interpretation of the spectra allowed a conclusion concerning the major long-chain base (the C(20) homolog of sphingosine) and the major fatty acids (C(22)-C(25) 2-hydroxy fatty acids), using reference spectra of synthetic galactosylceramides. A six-membered glycose ring (aldopyranose) was demonstrated by mass spectrometry of the acetyl derivative of periodic acid-oxidized and sodium borodeuteride-reduced pentosylceramide. By gas-liquid chromatography and mass spectrometry of methanolysis products, the pentose was shown to be identical with xylose. The procedures were applied to 25-50 micro g of glycolipid. PMID:4335795

  16. Nesting biology of laughing gulls in relation to agricultural chemicals in south Texas, 1978-81

    USGS Publications Warehouse

    White, D.H.; Mitchell, C.A.; Prouty, R.M.

    1983-01-01

    Laughing Gulls (Larus atricilla) were studied along the south Texas coast during 1978-1981 to determine productivity and to evaluate the effects of environmental pollutants on reproduction. The average clutch-size was 2.6, ranging from 2.3-2.8. Sixty-six percent of the eggs hatched and 82% of the pairs hatched at least one egg. Productivity (fledglings/total nests) averaged 1.0 fledgling per nest. DDE and other organochlorine residues were low in eggs (usually <3 ppm wet weight) and were not suspected of causing reproductive problems. However, organophosphate pesticides sprayed on crops near the study areas reduced productivity by as much as 33% during 3 of 4 years, implying that certain of these chemicals may pose serious threats to the population.

  17. Effects of laughing gull and shorebird predation on the intertidal fauna at Cape May, New Jersey

    NASA Astrophysics Data System (ADS)

    Botton, M. L.

    1984-02-01

    The intertidal flats of the Cape May, New Jersey shore of Delaware Bay are populated by large numbers of laughing gulls and migrating shorebirds during the spring and early summer. Exclusion of birds from a shallow slough and a sand bar had only minor effects on the infaunal benthic invertebrate assemblage at either site. The Cape May beaches provide a rich source of food in the form of horseshoe crab ( Limulus polyphemus) eggs; foraging on this item may be more profitable than probing the sediment for infauna. Gemma gemma, a small, thick-shelled bivalve, composed over 98% of the benthic infauna at both sites in 1980, and this species may be resistant to predation by certain shorebirds, as suggested by Schneider (1978).

  18. Organohalogen and metabolically-derived contaminants and associations with whole body constituents in Norwegian Arctic glaucous gulls.

    PubMed

    Verreault, J; Shahmiri, S; Gabrielsen, G W; Letcher, R J

    2007-08-01

    Comprehensive surveys of organohalogen contaminants have been conducted in various tissues and blood of glaucous gulls (Larus hyperboreus), a top scavenger-predator species in Svalbard in the Norwegian Arctic. However, the physico-chemical properties of organohalogens (e.g., type and degree of halogenation and the presence or absence of additional phenyl group substituents) that may influence toxicokinetics, and subsequently tissue-specific accumulation, have yet to be studied in this species. We investigated the concentrations, total body burdens, and compositional patterns of legacy chlorinated compounds (PCBs and chlordanes (CHLs)), metabolically-derived PCBs (methylsulfonyl (MeSO(2))- and OH-PCBs), brominated flame retardants (polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), total-hexabromocyclododecane (HBCD)), and PBDE metabolites and/or naturally-occurring compounds with similar structures (MeO- and OH-PBDEs) in liver, blood and whole body homogenate samples of adult glaucous gulls (n=19) from Svalbard. Further, we examined the distribution of these organohalogens and metabolites in relation to whole body composition of glaucous gulls, i.e., the total water, protein, lipid and mineral contents in whole homogenate carcasses. The total body burden of organohalogens and metabolites in glaucous gulls ranged between 3.3 and 33.0 mg. Compound class distribution showed that the relative proportions of sum (Sigma) OH-PCB and SigmaOH-PBDE to the total organohalogen concentrations were significantly highest in blood. Conversely, the SigmaCHL and SigmaPCB showed generally higher proportions in the lipid-rich liver as well as in whole body homogenates. No significant difference in the compositional patterns of individual congeners/compounds was found among tissues/blood, with the exception of the classes comprised of less polar brominated compounds (PBDEs, PBBs and total-(alpha)-HBCD). Total proteins isolated from the whole body homogenates of glaucous gulls were significantly associated to the proportions of SigmaOH-PCB and SigmaPBDE. A non-significant positive association was found between total lipids and the SigmaPCB proportions. The present study suggests that both protein association and lipid solubility are important concomitant factors to be considered in the toxicokinetics and fate of contaminants as a function of chemical structure and properties, e.g., chlorination, bromination and the presence of other phenyl substituents such as OH group. An enhanced, selective retention of these organohalogen classes in given tissues/body compartments may thus lead to site-specific toxicological actions and adverse effects in the highly-contaminated Svalbard glaucous gulls. PMID:17467797

  19. Age and accumulation of persistent organochlorines: a study of Arctic-breeding glaucous gulls (Larus hyperboreus).

    PubMed

    Bustnes, Jan Ove; Bakken, Vidar; Skaare, Janneche Utne; Erikstad, Kjell Einar

    2003-09-01

    We studied the relationship between increasing age and blood concentrations of four persistent organochlorines (OCs), hexachlorbenzene (HCB), oxychlordane, p,p'-dichlorodiphenyldichloroethylene (DDE), and 2,2',4,4',5,5'-hexachlorbiphenyl (PCB-153), in arctic-breeding glaucous gulls (Larus hyperboreus). We measured OC concentrations in 31 individuals of known age and took repeated blood samples of 64 individuals in different years, either one year apart or three or four years apart. The age of individuals was not related to the blood concentrations for any of the four compounds, and in birds whose values were measured repeatedly, there was no effect of the length of time (number of years) between sampling events on the relative change in OC concentration. This indicates that steady-state levels were reached before the age of first breeding. However, breeding area significantly influenced the changes in OC concentration between sampling events. In areas in which birds fed on prey from higher trophic levels, the OC concentrations showed large increases between sampling events; in areas in which birds fed at lower trophic levels, OC concentrations increased relatively little or not at all. This indicates that individual birds had different equilibrium concentrations, which are reached at different ages depending on the intake of OCs through the food. It also indicates that some individuals had not reached steady-state concentrations at the onset of reproduction. Changes in body condition and amount of blood lipids were of lesser importance than trophic level and influenced the concentrations of HCB and oxychlordane more strongly than DDE and PCB-153. In conclusion, this study indicates that steady-state concentrations of persistent OCs are reached early in life in most glaucous gulls, considering the long life span of the species. PMID:12959547

  20. Impact of egg harvesting on breeding success of black-headed gulls, Larus ridibundus

    NASA Astrophysics Data System (ADS)

    Wood, Philippa J.; Hudson, Malcolm D.; Doncaster, C. Patrick

    2009-01-01

    Gull colonies world-wide have been harvested for their eggs for centuries with minimal knowledge of the impacts on breeding. Although most Laridae can replace lost eggs, they have comparatively high energetic demands for egg production. In this paper we assess the impacts of a licensed egg harvest on the breeding success of black-headed gulls Larus ridibundus, which nest colonially in an EU Special Protection Area in Hampshire, southern England. We compared egg volume, hatching and chick survival from harvested and un-harvested nests in central and fringe positions within colonies of various sizes, including colonies with no harvesting activity. Eggs from various laying stages were collected from harvested and un-harvested colonies of similar pre-harvest intrinsic quality, for comparison of their volumes, yolk-to-albumen ratios and eggshell thickness. Egg volume and the yolk-to-albumen ratio depended on laying time and location, with the largest eggs laid during the peak period by birds breeding in central positions on large colonies. Eggs produced by these peak layers also had the largest yolk-to-albumen ratios. Harvested sites were characterised by reductions in egg volume, yolk-to-albumen ratio and eggshell thickness, which translated to poorer hatching success and chick survival. Harvested sites also had a higher proportion of abnormal eggs, particularly taking the forms of small yolkless eggs and unpigmented eggs. The reduced breeding success on harvested colonies is likely to be linked to depletion of the female's endogenous reserves which can also reduce future survival and breeding propensity.

  1. Streamlined Island

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-514, 15 October 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a streamlined island in Marte Vallis, a large outflow channel system that crosses the 180oW meridian between the Elysium and Amazonis regions of Mars. The flow patterns on the floor of Marte Vallis might be the remains of lava flows or mud flows. Marte is the Spanish word for Mars. Most of the largest valleys on the red planet are named for 'Mars' in various languages. This island is located near 21.8oN, 175.3oW. The picture covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  2. Thermal Islands

    NSDL National Science Digital Library

    In this problem-based learning unit, students learn about the causes and impacts of urban heat islands. Numerous studies have shown how concrete pavements and buildings retain heat in cities, making cities several degrees warmer than the surrounding countryside. Students investigate the role of cities in our climate, specifically how the urban heat island affects climate. Instructions to access NASA data are provided along with additional resources and activities. This module was developed for use in the Earth System Science Education Alliance (ESSEA) professional development courses for middle and high school teachers and is also available to teachers to adapt for general classroom use. See Related & Supplemental URLs for a demo course showing how this module is integrated into an ESSEA course for teachers.

  3. Organohalogen contamination in breeding glaucous gulls from the Norwegian Arctic: associations with basal metabolism and circulating thyroid hormones.

    PubMed

    Verreault, Jonathan; Bech, Claus; Letcher, Robert J; Ropstad, Erik; Dahl, Ellen; Gabrielsen, Geir W

    2007-01-01

    Exposure to organohalogens in endotherms has been suggested to impose chemically induced stress by affecting functions related to maintenance energy requirements. Effects on basal metabolic rate (BMR) have been suggested to be, in part, mediated through interactions with the thyroid hormones (THs). We investigated the relationships between plasma concentrations of major organochlorines, PBDEs, hydroxylated (OH)- and methoxylated (MeO)-PBDEs and OH-PCBs, circulating TH levels and BMR in breeding glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Negative associations were found between BMR and concentrations of sigma PCB, Sigma DDT and particularly Sigma chlordane, which combined made up 91% of the total contaminant burden. Levels of THs (thyroxine and triiodothyronine) were not associated significantly with variation of BMR or concentrations of any of the compounds determined. The present study suggests that BMR may be altered in glaucous gulls exposed to high loadings of persistent contaminants in the Norwegian Arctic environment. PMID:16713050

  4. Fish waste as an alternative resource for gulls along the Patagonian coast: availability, use, and potential consequences

    Microsoft Academic Search

    Pablo Yorio; Guillermo Caille

    2004-01-01

    We evaluated the volumes of waste from fish processing plants in Chubut Province, Argentina, and discuss its potential consequences for Kelp Gull (Larus dominicanus) population dynamics and coastal management. Mean volume of waste produced between 1989 and 2001 in three coastal cities was 49.8±10.9 thousand tonsy?1. The amount of waste varied between years and cities, being larger at Puerto Madryn

  5. Exploring plasticity in the wild: laying date–temperature reaction norms in the common gull Larus canus

    Microsoft Academic Search

    Jon E. Brommer; Kalev Rattiste; Alastair J. Wilson

    2008-01-01

    organism's ability to respond to climate change. Among individuals, variation in plasticity can be due to genotype-environment interaction (G!E) or a result from environmental effects associated with an individual. We investigated plasticity for laying date in the common gulls Larus canus, using data collected in Estonia during 37 years (nZ11 624 records on 2262 females, with 472 relatives). We used

  6. Heritability of head size in the common gull Larus canus in relation to environmental conditions during offspring growth

    Microsoft Academic Search

    Kjell Larsson; Kalev Rattiste; Vilju Lilleleht

    1997-01-01

    We studied the heritability of head length in a common gull (Larus canus) population breeding in western Estonia. Heritability estimates obtained from offspring-parent regressions were moderate to high and significantly different from zero. Head size might hence respond evolutionarily to phenotypic selection. Offspring-mother and offspring-father regressions yielded similar heritability estimates. This indicated that size-related maternal or paternal effects were absent

  7. Area utilization of gulls in a coastal farmland landscape: habitat mosaic supports niche segregation of opportunistic species

    Microsoft Academic Search

    Philipp Schwemmer; Stefan Garthe; Roger Mundry

    2008-01-01

    The intensively farmed coastal lowland landscape of Germany, adjacent to the North Sea, provides important foraging opportunities\\u000a for Black-headed, Common, Herring and Lesser Black-backed gull (Larus ridibundus, L. canus, L. argentatus and L. fuscus). We expected that spatial and temporal utilization of the landscape mosaic as well as behavioural traits and utilization\\u000a of food resources would differ between these closely

  8. Egg Production in a Coastal Seabird, the Glaucous-Winged Gull (Larus glaucescens), Declines during the Last Century

    PubMed Central

    Blight, Louise K.

    2011-01-01

    Seabirds integrate information about oceanic ecosystems across time and space, and are considered sensitive indicators of marine conditions. To assess whether hypothesized long-term foodweb changes such as forage fish declines may be reflected in a consumer's life history traits over time, I used meta-regression to evaluate multi-decadal changes in aspects of egg production in the glaucous-winged gull (Larus glaucescens), a common coastal bird. Study data were derived from literature searches of published papers and unpublished historical accounts, museum egg collections, and modern field studies, with inclusion criteria based on data quality and geographic area of the original study. Combined historical and modern data showed that gull egg size declined at an average of 0.04 cc y?1 from 1902 (108 y), equivalent to a decline of 5% of mean egg volume, while clutch size decreased over 48 y from a mean of 2.82 eggs per clutch in 1962 to 2.25 in 2009. There was a negative relationship between lay date and mean clutch size in a given year, with smaller clutches occurring in years where egg laying commenced later. Lay date itself advanced over time, with commencement of laying presently (2008–2010) 7 d later than in previous studies (1959–1986). This study demonstrates that glaucous-winged gull investment in egg production has declined significantly over the past ?50–100 y, with such changes potentially contributing to recent population declines. Though gulls are generalist feeders that should readily be able to buffer themselves against food web changes, they are likely nutritionally constrained during the early breeding period, when egg production requirements are ideally met by consumption of high-quality prey such as forage fish. This study's results suggest a possible decline in the availability of such prey, and the incremental long-term impoverishment of a coastal marine ecosystem bordering one of North America's rapidly growing urban areas. PMID:21789207

  9. Organohalogen and metabolically-derived contaminants and associations with whole body constituents in Norwegian Arctic glaucous gulls

    Microsoft Academic Search

    J. Verreault; S. Shahmiri; G. W. Gabrielsen; R. J. Letcher

    2007-01-01

    Comprehensive surveys of organohalogen contaminants have been conducted in various tissues and blood of glaucous gulls (Larus hyperboreus), a top scavenger-predator species in Svalbard in the Norwegian Arctic. However, the physico-chemical properties of organohalogens (e.g., type and degree of halogenation and the presence or absence of additional phenyl group substituents) that may influence toxicokinetics, and subsequently tissue-specific accumulation, have yet

  10. Validation of the use of blood samples to assess tissue concentrations of organochlorines in glaucous gulls, Larus hyperboreus

    Microsoft Academic Search

    Espen O. Henriksen; Geir W. Gabrielsen; Janneche Utne Skaare

    1998-01-01

    Fifteen adult glaucous gulls, Larus hyperboreus, were captured near Ny-Ålesund, Svalbard. The birds were kept in captivity for 24–41 days and fed a diet of polar cod, Boreogadus saida. A range of organochlorines (OCs) were quantified in blood, brain, liver, and subcutaneous fat tissue. For more than 80% of the quantified OCs, r2 values >0.75 were found for the blood-liver

  11. Thermoregulation and Sleep: Effects of Thermal Stress on Sleep Patterns of Glaucous-Winged Gulls (Larus glaucescens)

    Microsoft Academic Search

    Mark R. Opp; Nigel J. Ball; Don E. Miller; Charles J. Amlaner

    1987-01-01

    1. To determine effects of thermal stress on avian sleep patterns, incubating Glaucous-winged gulls were subjected to conditions of heat loss and heat gain via conduction from hollow copper eggs.\\u000a2. Heated manipulations resulted in significant reductions in sleep and rest relative to controls, whereas cooled manipulations had little effect.\\u000a3. The resilience of sleep to thermal stress is greater

  12. Prevalence of influenza A antibodies in yellow-legged gull (Larus michahellis) eggs and adults in southern Tunisia.

    PubMed

    Hammouda, Abdessalem; Pearce-Duvet, Jessica; Chokri, Mohamed Ali; Arnal, Audrey; Gauthier-Clerc, Michel; Boulinier, Thierry; Selmi, Slaheddine

    2011-12-01

    Investigating the prevalence of anti-influenza A viruses (AIV) antibodies in wild birds can provide important information for the understanding of bird exposure to AIV, as well as for prevention purposes. We investigated AIV exposure in nature by measuring the prevalence of anti-AIV antibodies in the nests and adults of an abundant and anthropophilic waterbird species common around the Mediterranean sea, the yellow-legged gull (Larus michahellis). Sampling took place in two colonies located in the gulf of Gabès in southern Tunisia: Sfax and Djerba. Antibodies were detected in the two sites, with higher prevalence in adults, eggs, and nests at Sfax than Djerba. Across both colonies, clutches that were laid later in the season, and, thus, more likely by younger parents, showed lower prevalence. Using patch occupancy modeling applied to egg clutches, we found that it is unnecessary to sample all the eggs in a given nest; nest status (antibody positive or negative) can be reliably estimated from a single egg. Differences in the density of birds, notably Larids, between the two sites may explain the observed differences in prevalence. The higher concentration of Larids in the Sfax colony could favor the transmission of AIV to yellow-legged gulls. This study highlights the importance of further developing ecological-based approaches to the factors determining the circulation of infectious agents in species such as the yellow-legged gull, which exist at the interface between diverse biological communities and human activities. PMID:21919723

  13. Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos.

    PubMed

    Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A

    1999-03-01

    Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. PMID:10064546

  14. Climate variability and temporal trends of persistent organic pollutants in the arctic: a study of glaucous gulls.

    PubMed

    Bustnes, Jan O; Gabrielsen, Geir W; Verreault, Jonathan

    2010-04-15

    The impact of climate variability on temporal trends (1997-2006) of persistent organic pollutants (POPs; polychlorinated biphenyls [PCB], hexachlorobenzene [HCB], and oxychlordane) was assessed in glaucous gulls (Larus hyperboreus) breeding in the Norwegian Arctic (n = 240). The Arctic Oscillation (AO: an index of sea-level pressure variability in the Northern Hemisphere above 20 degrees N) with different time lags was used as a climate proxy. The estimated concentrations of POPs in glaucous gull blood/plasma declined substantially (16-60%) over the time period. Multiple regression analyses showed that the rates of decline for POPs were correlated to climate variation when controlling for potential confounding variables (sex and body condition). More specifically AO in the current winter showed negative associations with POP concentrations, whereas the relationships with AO measurements from the year preceding POP measurements (AO preceding summer and AO preceding winter) were positive. Hence, gulls had relatively higher POP concentrations in breeding seasons following years with high air transport toward the Arctic. Furthermore, the impact of AO appeared to be stronger for HCB, a relatively volatile compound with high transport potential, compared to heavy chlorinated PCB congeners. This study thus suggests that predicted climate change should be considered in assessments of future temporal trends of POPs in Arctic wildlife. PMID:20297811

  15. Intraspecific variation in trophic feeding levels and organochlorine concentrations in glaucous gulls (Larus hyperboreus) from Bjørnøya, the Barents Sea.

    PubMed

    Sagerup, Kjetil; Henriksen, Espen O; Skaare, Janneche U; Gabrielsen, Geir W

    2002-04-01

    Biomagnification contributes to high concentrations of persistent organochlorines (OC) in some Arctic vertebrates. Glaucous gulls (Larus hyperboreus) on Bjørnøya in the western Barents Sea were studied to compare the intraspecific variation in OC concentration with variation in trophic feeding levels, estimated from ratios of nitrogen isotopes. Liver tissue samples from 40 adult glaucous gulls were analysed for hexachlorobenzene (HCB), oxychlordane, p,p'-dichlorodiphenyltrichloroethane (DDT) and its metabolite p,p'-DDE, Mirex, and nine congeners of polychlorinated biphenyl (PCB). The ratios of the heavier to lighter isotope of carbon (13C/12C) and nitrogen (15N/14N), expressed as delta13C and delta15N, were measured in liver and muscle. Hepatic concentrations of the nine PCB congeners (Sigma 9 PCB) ranged from 16 microg/g lipid weight to 292 microg/g lipid weight. The delta15N ranged from 14.0/1000 to 15.3/1000 in muscle. Seven of the 14 OC measured, sigma DDT, and sigma 9 PCB were positively correlated to delta15N from muscle tissue. No correlations were found between OC and delta13C. The present results indicate that OC concentrations are partly dependent on the foraging strategy of the gull. The r2 of the linear regressions suggests that up to 18% of the variation in the OC concentrations could be explained by variation in food preference. PMID:11990768

  16. Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos.

    PubMed Central

    Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A

    1999-01-01

    Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10064546

  17. Groundwater flow near the Shoal Site, Sand Springs Range, Nevada: Impact of density-driven flow

    SciTech Connect

    Chapman, J.; Mihevc, T.; McKay, A.

    1994-09-01

    The nature of flow from a highland recharge area in a mountain range in north-central Nevada to discharge areas on either side of the range is evaluated to refine a conceptual model of contaminant transport from an underground nuclear test conducted beneath the range. The test, known as the Shoal event, was conducted in 1963 in granitic rocks of the Sand Springs Range. Sparse hydraulic head measurements from the early 1960s suggest flow from the shot location to the east to Fairview Valley, while hydrochemistry supports flow to salt pans in Fourmile Flat to the west. Chemical and isotopic data collected from water samples and during well-logging arc best explained by a reflux brine system on the west side of the Sand Springs Range, rather than a typical local flow system where all flow occurs from recharge areas in the highlands to a central discharge area in a playa. Instead, dense saline water from the playa is apparently being driven toward the range by density contrasts. The data collected between the range and Fourmile Flat suggest the groundwater is a mixture of younger, fresher recharge water with older brine. Chemical contrasts between groundwater in the east and west valleys reflect the absence of re-flux water in Fairview Valley because the regional discharge area is distant and thus there is no accumulation of salts. The refluxing hydraulic system probably developed after the end of the last pluvial period and differences between the location of the groundwater divide based on hydraulic and chemical indicators could reflect movement of the divide as the groundwater system adjusts to the new reflux condition.

  18. Two's company, three's a crowd: food and shelter limitation outweigh the benefits of group living in a shoaling fish.

    PubMed

    Ford, John R; Swearer, Stephen E

    2013-05-01

    Identifying how density and number-dependent processes regulate populations is important for predicting population response to environmental change. Species that live in groups, such as shoaling fish, can experience both direct density-dependent mortality through resource limitation and inverse number-dependent mortality via increased feeding rates and predator evasion in larger groups. To investigate the role of these processes in a temperate reef fish population, we manipulated the density and group size of the shoaling species Trachinops caudimaculatus on artificial patch reefs at two locations with different predator fields in Port Phillip Bay, Australia. We compared mortality over four weeks to estimates of predator abundance and per capita availability of refuge and food to identify mechanisms for density or number dependence. Mortality was strongly directly density dependent throughout the experiment, regardless of the dominant predator group; however, the limiting resource driving this effect changed over time. In the first two weeks when densities were highest, density-dependent mortality was best explained by refuge competition and the abundance of benthic predators. During the second two weeks, food competition best explained the pattern of mortality. We detected no effect of group size at either location, even where pelagic-predator abundance was high. Overall, direct density effects were much stronger than those of group size, suggesting little survival advantage to shoaling on isolated patch reefs where resource competition is high. This study is the first to observe a temporal shift in density-dependent mechanisms in reef fish, and the first to observe food limitation on short temporal scales. Food competition may therefore be an important regulator of postsettlement reef fish cohorts after the initial intense effects of refuge limitation and predation. PMID:23858647

  19. Comprehensive re-analysis of archived herring gull eggs reconstructs historical temporal trends in chlorinated hydrocarbon contamination in Lake Ontario and Green Bay, Lake Michigan, 1971-1982.

    PubMed

    Norstrom, Ross J; Hebert, Craig E

    2006-08-01

    Herring gull egg homogenates collected between 1971 and 1982 from a colony in central Lake Ontario (Scotch Bonnet Island) and from a colony in central Green Bay, Lake Michigan (Big Sister Island) were archived in the Canadian Wildlife Service Specimen Bank. Pooled samples (N = 10) were exhaustively analyzed in 1993 for a wide range of individual chlorinated hydrocarbon contaminant (CHC) compounds: DDT, mirex and chlordane compounds and metabolites, chlorobenzenes (CBzs), dieldrin, chlorostyrenes (CSs), hexachlorocyclohexanes (HCHs), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and 87 PCB congeners, including the TCDD-like non-ortho and mono-ortho congeners. PCBs and DDTs were the dominant residues in eggs from both Lake Ontario (31-242 mg kg(-1) and 9-64 mg kg(-1)) and Green Bay (34-133 mg kg(-1) and 14-91 mg kg(-1)). SigmaPCBs declined by a factor of 4-5 and DDTs a factor of 4-7 at both colonies between 1971 and 1982. Lake Ontario eggs had significantly higher residues of 2,3,7,8-TCDD (0.2-2.0 microg kg(-1)), HCBz (0.1-4.7 mg kg(-1)), OCS (0.03-0.45 mg kg(-1)), three HpCSs (0.13-0.97 mg kg(-1)), mirex and mirex photodegradation products (2.1-9.2 mg kg(-1)) than Green Bay eggs. HCBz levels in Lake Ontario eggs declined a factor of 40, TCDD and chlorostyrenes a factor of 8-10, and mirex a factor of 4 between 1971-1978. Green Bay eggs had slightly higher levels of chlordane-related compounds, dieldrin and beta-HCH than Lake Ontario eggs. There were no consistent or strong trends in residue levels of these pesticides, PCDDs (except TCDD) and PCDFs in either lake, indicating that rates of input and removal of these CHCs in the lakes were much closer in the early 1970s than was the case for the other compounds. PMID:16896467

  20. An investigation of the origin of large water level oscillations during storms at Banneg Island, France

    NASA Astrophysics Data System (ADS)

    Staples, T.; TIAN, M.; Ardhuin, F.; Sheremet, A.; Suanez, S.; Fichaut, B.

    2012-12-01

    We investigate the generation mechanism for unusually high water levels observed at Banneg Island, France, where loose boulders have been reportedly transported during storms over distances exceeding 100m (Fichaut and Suanez, 2011). The site is characterized by steep cliffs with slopes from 0.3 to 3 and composed of fractured rock and boulders. The lowest points along Banneg Island cliff crest are at 5m above the highest predicted tide, which is 10m above mean sea level. Wave and tide levels were observed using pressure gauges over a period of approximately 7 months. Two gauges (P3 and P4) were deployed offshore near the 4m isobath, and were submerged for the entire duration of the experiment. A third gauge (P2), located on the island just above the maximum predicted tide, and approximately cross-shore with respect to P3, was intermittently submerged during storms, for periods of the order of 2-3 min. On milder slopes (Sheremet et al. 2011), nonlinear shoaling of wind waves is typically associated with the generation of infragavity (IG) waves. We investigate the relationship between the water level oscillations observed at Banneg Island, and wave set-up and infragravity waves generated during swell shoaling. To circumvent the difficulty posed by the intermittent P2 signal, wavelet cross-correlation and cross-bispectral analysis is used to study the phase correlation between the swell envelope and IG waves at P3 and P4. A uni-directional deterministic wave model (Agnon and Sheremet, 1997) is used to investigate the generation mechanism, and assess the magnitude of the infragravity waves. REFERENCES Agnon, Y and A. Sheremet. Stochastic nonlinear shoaling of directional spectra. Journal of Fluid Mechanics. 345, p. 79-99, 1997. Fichaut, B and S. Suanez. Quarrying, transport and deposition of cliff-top storm deposits during extreme events: Banneg island. Marine Geology, pages 36-55, 2011. Sheremet, A, J. Kaihatu, S. Su, E. Smith, and J. Smith. Modeling of nonlinear wave propagation over fringing reefs. Coastal Engineering. 58(12). 1125-1137, 2011.

  1. Carolinas Coastal Change Processes Project data report for observations near Diamond Shoals, North Carolina, January-May 2009

    USGS Publications Warehouse

    Armstrong, Brandy N.; Warner, John C.; Voulgaris, George; List, Jeffrey H.; Thieler, E. Robert; Martini, Marinna A.; Montgomery, Ellyn T.

    2011-01-01

    This Open-File Report provides information collected for an oceanographic field study that occurred during January - May 2009 to investigate processes that control the sediment transport dynamics at Diamond Shoals, North Carolina. The objective of this report is to make the data available in digital form and to provide information to facilitate further analysis of the data. The report describes the background, experimental setup, equipment, and locations of the sensor deployments. The edited data are presented in time-series plots for rapid visualization of the data set, and in data files that are in the Network Common Data Format (netcdf). Supporting observational data are also included.

  2. Alcatraz Island

    NSDL National Science Digital Library

    2005-01-01

    â??The Rockâ?, the oft-used vernacular phrase used to describe Alcatraz, is perhaps one of the Bay Areaâ??s most dramatic landscapes, and certainly itâ??s best known island. Over the past several hundred years, it has served at times as a place for protest by Native Americans and a place of incarceration for some of Americaâ??s most hardened (and colorful) criminals. The National Park Service recently created this rather well-done online exhibit that allows users to view objects from Alcatrazâ??s past (such as escape materials and historic photographs) and also to allow them to take a virtual tour of the prison and its grounds. Visitors can also listen to a number of compelling sound clips that discuss the infamous â??Battle of Alcatrazâ? and the cellhouse rules. The site also features a number of thematic slide shows, including one that addresses the occupation of the island by members of the American Indian Movement from 1969 to 1971.

  3. Tenarife Island, Canary Island Archipelago, Atlantic Ocean

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Tenarife Island is one of the most volcanically active of the Canary Island archipelago, Atlantic Ocean, just off the NW coast of Africa, (28.5N, 16.5W). The old central caldera, nearly filled in by successive volcanic activity culminating in two stratocones. From those two peaks, a line of smaller cinder cones extend to the point of the island. Extensive gullies dissect the west side of the island and some forests still remain on the east side.

  4. Transmission of H5N1 high pathogenicity avian influenza virus to Herring gulls (Larus argentatus) through intranasal inoculation of virus and ingestion of virus-infected chicken meat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to evaluate the susceptibility of herring gulls (Larus argentatus) to H5N1 highly pathogenic avian influenza (HPAI) virus under natural routes of infection, we exposed gulls to two Asian lineage H5N1 HPAI viruses (A/whooper swan/Mongolia/244/05 and A/duck meat/Anyang/AVL-1/01) via intranasa...

  5. An experimental investigation of a direct life-cycle in Reighardia sternae (Diesing, 1864), a pentastomid parasite of the herring gull (Larus argentatus).

    PubMed

    Banaja, A A; James, J L; Riley, J

    1975-12-01

    A direct life-cycle in Reighardia sternae, a cephalobaenid pentastomid of gulls was investigated: the work was prompted by a report of eggs and larvae recovered from the stomach and intestine of a naturally infected gull. Infective pentastomid eggs were obtained by surgically transplanting maturing female Reighardia, taken from freshly shot wild gulls, into captive recipients. Faecal material from birds thus artificially infected was collected daily and examined for eggs. Eggs were force fed to 33 hand-reared (from eggs or nestlings) juvenile gulls which were selected at random and sacrificed at intervals thereafter and examined for pentastomids. One hour after infection, primary larvae appear in the body cavity where they moult immediately. They grow steadily and by 27-35 days are sexually differentiated, and by 66 days have copulated. Fertilized females take a further 116 days to produce eggs by which time they are 7-6 cm long. The complex migrations undertaken by developing larvae in the gull, and the problems of the mechanism of direct transmission, are discussed. PMID:1202414

  6. Island Formation: Constructing a Coral Island

    ERIC Educational Resources Information Center

    Austin, Heather; Edd, Amelia

    2009-01-01

    The process of coral island formation is often difficult for middle school students to comprehend. Coral island formation is a dynamic process, and students should have the opportunity to experience this process in a synergistic context. The authors provide instructional guidelines for constructing a coral island. Students play an interactive role…

  7. 2012 Groundwater Monitoring Report Project Shoal Area Subsurface Corrective Action Unit 447

    SciTech Connect

    None

    2013-03-01

    The Project Shoal Area (PSA) in Nevada was the site of a 12-kiloton underground nuclear test in 1963. Although the surface of the site has been remediated, investigation of groundwater contamination resulting from the test is still in the corrective action process. Annual sampling and hydraulic head monitoring are conducted at the site as part of the subsurface corrective action strategy. Analytical results from the 2012 monitoring are consistent with those of the previous years, with tritium detected only in well HC-4. The tritium concentration in groundwater from well HC-4 remains far below the U.S. Environmental Protection Agency-established maximum contaminant level of 20,000 picocuries per liter. Concentrations of total uranium and gross alpha were also detected during this monitoring period, with uranium accounting for nearly all the gross alpha activity. The total uranium concentrations obtained from this monitoring period were consistent with previous results and reflect a slightly elevated natural uranium concentration, consistent with the mineralized geologic terrain. Isotopic ratios of uranium also indicate a natural source of uranium in groundwater, as opposed to a nuclear-test-related source. Water level trends obtained from the 2012 water level data were consistent with those of previous years. The corrective action strategy for the PSA is currently focused on revising the site conceptual model (SCM) and evaluating the adequacy of the current monitoring well network. Some aspects of the SCM are known; however, two major concerns are the uncertainty in the groundwater flow direction and the cause of rising water levels in site wells west of the shear zone. Water levels have been rising in the site wells west of the shear zone since the first hydrologic characterization wells were installed in 1996. While water levels in wells west of the shear zone continue to rise, the rate of increase is less than in previous years. The SCM will be revised, and an evaluation of the groundwater monitoring network will be conducted when water levels at the site have stabilized.

  8. Reproductive success in presenescent common gulls (Larus canus): the importance of the last year of life.

    PubMed Central

    Rattiste, Kalev

    2004-01-01

    Survival selection against individuals of inferior quality (measured as breeding success) has been proposed to account for the increase in average reproductive success with advancing age in presenescent birds. This so-called selection hypothesis relies on quality-dependent survival. In the present breeding performance study of common gulls, Larus canus, this assumption was not verified. In particular, omitting the last breeding year from the analysis resulted in the disappearance of the correlation between breeding success and survival. A positive correlation in the full dataset was thus solely based on the poor breeding success of ultimate breeders. Indeed, presenescent individuals were shown to have a specifically low breeding success in their terminal breeding event. The poor success of ultimate breeders thus reflects an abruptly declined condition rather than the birds' overall quality. A comparison of the survival of poor and good performers, involving last-time breeders, thus needs not to be a proper test of the selection hypothesis. Longitudinal analysis revealed a steady increase of individual breeding success until the tenth breeding year. The results suggest that an increase of breeding success with age often found in cross-sectional analyses is primarily a result of age-related improvements of competence and/or increased reproductive effort. PMID:15451696

  9. Reproductive success in presenescent common gulls (Larus canus): the importance of the last year of life.

    PubMed

    Rattiste, Kalev

    2004-10-01

    Survival selection against individuals of inferior quality (measured as breeding success) has been proposed to account for the increase in average reproductive success with advancing age in presenescent birds. This so-called selection hypothesis relies on quality-dependent survival. In the present breeding performance study of common gulls, Larus canus, this assumption was not verified. In particular, omitting the last breeding year from the analysis resulted in the disappearance of the correlation between breeding success and survival. A positive correlation in the full dataset was thus solely based on the poor breeding success of ultimate breeders. Indeed, presenescent individuals were shown to have a specifically low breeding success in their terminal breeding event. The poor success of ultimate breeders thus reflects an abruptly declined condition rather than the birds' overall quality. A comparison of the survival of poor and good performers, involving last-time breeders, thus needs not to be a proper test of the selection hypothesis. Longitudinal analysis revealed a steady increase of individual breeding success until the tenth breeding year. The results suggest that an increase of breeding success with age often found in cross-sectional analyses is primarily a result of age-related improvements of competence and/or increased reproductive effort. PMID:15451696

  10. Tissue levels of lead in experimentally exposed herring gull (Larus argentatus) chicks.

    PubMed

    Burger, J; Gochfeld, M

    1990-01-01

    Two-day-old herring gull (Larus argentatus) chicks were injected with either 0.1 or 0.2 mg lead/g body mass and were sacrificed at 45 d of age. Control birds were injected with sterile water. We examined lead and cadmium levels in blood, kidney, liver, muscle, salt glands, breast feathers, and bone. In control birds lead levels were highest in bone, feathers, salt gland, and kidney, and lowest in blood, muscle, and brain. In experimental birds lead levels were highest in bone, liver, kidney, and feathers, and lowest in blood, muscle, and salt gland. In control birds cadmium levels were highest in the kidney, followed by liver, with blood and brain being the lowest. Lead-exposed birds had increased cadmium deposition in brain. For experimental birds lead levels were correlated for all tissues except the salt gland. Correlations were particularly high for feathers with brain, kidney, liver and bone, suggesting feathers can be used in biomonitoring of natural avian populations. For cadmium there were no significant correlations among tissue levels except for brain and liver. Bioamplification of lead was greatest for liver and blood, and lowest for muscle and salt gland when comparing a lead dose of 0.1 mg/g with controls. PMID:2299695

  11. Intracellular concentrations of the salt gland of the herring gull Larus argentatus.

    PubMed

    Schmidt-Nielsen, B

    1976-02-01

    Attempts were made to measure intra- and extracellular concentrations in secreting and inactive salt gland tissue of the herring gull. 14C-labeled polyethylene glycol (mol wt 4,000) was used as a marker for extracellular fluid. Fluid separated by centrifugation at 36,000 g appeared by three independent criteria to represent primarily extracellular fluid. It could not, however, be fully ascertained if this fluid was mixed with a small amount of intracellular fluid. Therefore, intracellular concentrations were calculated from the concentrations in centrifuged fluid as well as from plasma concentrations. By either method it was found that secreting and inactive glands showed no difference in extracellular and intracellular fluid concentrations of Na, K, Cl and Ca. Secreting glands had lower intracellular water content and a higher intracellular Mg concentration than inactive glands. The absence of evidence for intracellular accumulation of Na and Cl ions in secreting glands suggests that active ion transport takes place across the apical rather than the basal and lateral membranes in spite of the fact that Na-K-activated ATPase is associated with the extensive infoldings of these plasma membranes. PMID:1259030

  12. The blood vascular system in the head of the herring gull (Larus argentatus).

    PubMed

    Midtgård, U

    1984-02-01

    The structure and development of the blood vascular system in the head of the herring gull (Larus argentatus) have been studied using injection techniques and histological sections. Three different but interconnected divisions of the arterial system are recognized in the adult: the cerebral carotid artery system, the external ophthalmic artery system, and the external carotid artery system. Embryologically, the arterial system is characterized by changes in the relative development of these divisions; the cerebral carotid system being the most prominent in the first half of the embryonic period. The venous system is divided into two parts, the rostral cephalic system and the caudal cephalic system, which drain separate regions of the head. The Rete ophthalmicum , which is an arteriovenous network associated with the external ophthalmic artery system, can be identified from the fifth day of incubation, and its development appears to be coupled with changes in the arterial supply to the eye. The possibility of a homology between the Rete ophthalmicum of birds and the Rete caroticum of mammals is briefly discussed. PMID:6538908

  13. Maternal transfer of organohalogen contaminants and metabolites to eggs of Arctic-breeding glaucous gulls.

    PubMed

    Verreault, Jonathan; Villa, Rosa A; Gabrielsen, Geir W; Skaare, Janneche U; Letcher, Robert J

    2006-12-01

    Eggs of seabirds have routinely been used as indicators of environmental pollution in the Arctic. However, the variability in organohalogen concentration and composition associated with the laying sequence, have not been defined. We examined a suite of PCBs, organochlorine (OC) pesticides and by-products, polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs) and methylsulfonyl- (MeSO2) PCBs in complete 3-egg clutches of glaucous gulls (Larus hyperboreus), and plasma samples of the laying females collected from the Norwegian Arctic. SigmaPCB, SigmaOC and SigmaPBDE, but not SigmaMeSO2-PCB, concentrations in eggs were positively associated, with increasing magnitude and significance from the first through the last-laid egg, with concentrations in female plasma. However, the concentrations of these organohalogen classes fluctuated irrespective of the laying order in the clutch. In general, maternal transfer favored low K(ow) and/or less persistent compounds, whereas the recalcitrant and/or higher-halogenated compounds were less readily transferred, and consequently more selectively retained in the mother. PMID:16563578

  14. Toxicological investigations of pollutant-related effects in Great Lakes gulls.

    PubMed Central

    Peakall, D B; Fox, G A

    1987-01-01

    Reproductive failure of a number of fish-eating birds was observed on the Great Lakes in the mid-1960s to mid-1970s. The herring gull (Larus argentatus) has been used as the primary monitoring species. The low hatching success observed in this species on Lake Ontario in the mid-1970s was due to loss of eggs and failure of eggs to hatch. Egg exchange experiments demonstrated that this was due both to the incubation behavior of adults and to direct embryotoxic effects. Decrease of nest attentiveness was demonstrated using telemetered eggs, but attempts to reproduce the embryonic effects by injection of pollutant mixtures into eggs were not successful. Reproductive success improved rapidly during the late 1970s and was normal by the end of the decade. Recent studies have focused on cytogenetic and biochemical changes and detailed analytical chemistry of residues. No changes in the rate of sister chromatid exchange over values determined in coastal colonies were observed. Elevation of hepatic aryl hydrocarbon hydroxylase activity, levels of highly carboxylated porphyrins, and changes of thyroid function have been found. The geographic pattern of these changes indicates that they are caused by xenobiotics, but it has not been possible to relate the changes to a specific chemical. PMID:3297661

  15. Age-dependent changes in plasma biochemistry of yellow-legged gulls (Larus cachinnans).

    PubMed

    Alonso-Alvarez, Carlos

    2005-04-01

    The study of avian plasma chemistry is providing useful reference values for the management of endangered and game species, supporting veterinarians in their diagnostics, and also bringing to light relevant physiological adaptations during periods of food-shortage. Age is an important source of variability for plasma chemistry. Here I report plasma chemistry of yellow-legged gulls Larus cachinnans from different ages, between post-independence and adulthood, a 5-year interval. Increase in plasma cholesterol concentration and decreases in uric acid, inorganic phosphorus and alkaline phosphatase values were seen. Body mass corrected by body size (i.e. body condition) increased with age, plasma cholesterol being positively correlated in females, but not in males. Moreover, cholesterol was also positively correlated to gonad size in both sexes. Long-term developmental changes in this species, such as gonad development and the acquisition of an optimal body mass for reproduction, could explain these findings. Finally, inorganic phosphorus and alkaline phosphatase, both traditionally related to osteogenesis, were not associated to deferred skull ossification, as originally was suggested in other species. PMID:15936712

  16. Rhode Island Transportation

    E-print Network

    Rhode Island, University of

    Rhode Island Transportation Fact Book Highlights Transportation Center #12;Transportation in Rhode Island University of Rhode Island Transportation Center 2 Road Conditions / Road Ownership Public Road Length by Ownership 2008 Road Conditions 2008 9% 17% 45% 18% 11% Rhode Island Road Condition (2008

  17. Changing gull diet in a changing world: a 150-year stable isotope (?13C, ?15N) record from feathers collected in the Pacific Northwest of North America.

    PubMed

    Blight, Louise K; Hobson, Keith A; Kyser, T Kurt; Arcese, Peter

    2015-04-01

    The world's oceans have undergone significant ecological changes following European colonial expansion and associated industrialization. Seabirds are useful indicators of marine food web structure and can be used to track multidecadal environmental change, potentially reflecting long-term human impacts. We used stable isotope (?(13)C, ?(15)N) analysis of feathers from glaucous-winged gulls (Larus glaucescens) in a heavily disturbed region of the northeast Pacific to ask whether diets of this generalist forager changed in response to shifts in food availability over 150 years, and whether any detected change might explain long-term trends in gull abundance. Sampled feathers came from birds collected between 1860 and 2009 at nesting colonies in the Salish Sea, a transboundary marine system adjacent to Washington, USA and British Columbia, Canada. To determine whether temporal trends in stable isotope ratios might simply reflect changes to baseline environmental values, we also analysed muscle tissue from forage fishes collected in the same region over a multidecadal timeframe. Values of ?(13)C and ?(15)N declined since 1860 in both subadult and adult gulls (?(13)C, ~ 2-6‰; ?(15)N, ~4-5‰), indicating that their diet has become less marine over time, and that birds now feed at a lower trophic level than previously. Conversely, forage fish ?(13)C and ?(15)N values showed no trends, supporting our conclusion that gull feather values were indicative of declines in marine food availability rather than of baseline environmental change. Gradual declines in feather isotope values are consistent with trends predicted had gulls consumed less fish over time, but were equivocal with respect to whether gulls had switched to a more garbage-based diet, or one comprising marine invertebrates. Nevertheless, our results suggest a long-term decrease in diet quality linked to declining fish abundance or other anthropogenic influences, and may help to explain regional population declines in this species and other piscivores. PMID:25369474

  18. Low-frequency target strength and abundance of shoaling Atlantic herring (Clupea harengus) in the Gulf of Maine during the Ocean Acoustic Waveguide Remote Sensing 2006 Experiment.

    PubMed

    Gong, Zheng; Andrews, Mark; Jagannathan, Srinivasan; Patel, Ruben; Jech, J Michael; Makris, Nicholas C; Ratilal, Purnima

    2010-01-01

    The low-frequency target strength of shoaling Atlantic herring (Clupea harengus) in the Gulf of Maine during Autumn 2006 spawning season is estimated from experimental data acquired simultaneously at multiple frequencies in the 300-1200 Hz range using (1) a low-frequency ocean acoustic waveguide remote sensing (OAWRS) system, (2) areal population density calibration with several conventional fish finding sonar (CFFS) systems, and (3) low-frequency transmission loss measurements. The OAWRS system's instantaneous imaging diameter of 100 km and regular updating enabled unaliased monitoring of fish populations over ecosystem scales including shoals of Atlantic herring containing hundreds of millions of individuals, as confirmed by concurrent trawl and CFFS sampling. High spatial-temporal coregistration was found between herring shoals imaged by OAWRS and concurrent CFFS line-transects, which also provided fish depth distributions. The mean scattering cross-section of an individual shoaling herring is found to consistently exhibit a strong, roughly 20 dB/octave roll-off with decreasing frequency in the range of the OAWRS survey over all days of the roughly 2-week experiment, consistent with the steep roll-offs expected for sub-resonance scattering from fish with air-filled swimbladders. PMID:20058955

  19. In: J. Waterway, Port, Coastal, and Ocean Engineering, 126(3): 305-313, 2000. Reservoir Model of Ebb-Tidal Shoal Evolution and Sand Bypassing

    E-print Network

    US Army Corps of Engineers

    of Ebb-Tidal Shoal Evolution and Sand Bypassing By Nicholas C. Kraus,1 Member, ASCE ABSTRACT A mathematical model is presented for calculating the change in volume and sand-bypassing rate at ebb reservoir can fill to a maximum (equilibrium) volume. The ratio of the input longshore sand transport rate

  20. Some observations on egg production and autoreinfection of Reighardia sternae (Diesing, 1864), a pentastomid parasite of the herring gull.

    PubMed

    Banaja, A A; James, J L; Riley, J

    1976-02-01

    Egg production by Reighardia sternae, implanted at various stages of maturity into the interclavicular air sacs of captive gulls, is described. Females produce only 2900 eggs per lifetime over a short patent period of 1-3 days. The problem of a direct life-cycle in relation to this unusually low fecundity is discussed, and speculation is advanced concerning a possible parasitic behavioural trait which could facilitate direct transmission. The hazards of the latter are also offset by auto-reinfection. PMID:1256912

  1. Desktop Study for La Quinta Project; Shoaling Prediction in La Quinta Navigation Channel and Effect of a Barrier on Siltation in Extended La Quinta Channel

    NASA Astrophysics Data System (ADS)

    Parchure, Trimbak M.; Sarruff, Soraya; Brown, Ben

    2002-09-01

    The U.S. Army Engineer District, Galveston, proposed two modifications of the La Quinta navigation channel: (1) extension of the navigation channel and providing a new turning basin at the end of the extension, both having the same depth as that of the present navigation channel, namely 13.7 m (45 ft), and (2) constructing a barrier on the south side of the extended channel. The District requested the Coastal and Hydraulics Laboratory (CHL) of the U.S. Army Engineer Research and Development Center (ERDC), Vicksburg, MS, conduct a desktop study for estimation of future shoaling in the navigation channel with these two modifications. The results of a desktop study are given in this report in two parts for the above two problems. Shoaling Prediction in La Quinta Navigation Channel The approach consisted of the following steps. Field data already available as well as those collected by CHL were analyzed and the results of analysis used. Assumptions were made on the spatial and temporal variation in the values of relevant parameters. Runs were conducted on the existing numerical hydrodynamic model for a few selected conditions to determine the effect of channel extension on the currents in the area of interest. A quantitative estimate was provided on future shoaling in the navigation channel based on the field and model data analysis. The following conclusions were drawn. a. Proposed extension of La Quinta navigation channel and provision of a new turning basin will cause an increase in the present tidal currents. This is expected to increase the inflow of sediment in the channel, which would result in increased shoaling. b. Bed sediment in the La Quinta channel consists of mostly fine sediment in the category of silt and clay. This suggests that the major process of shoaling consists of deposition of suspended sediment.

  2. Immunological and reproductive health assessment in herring gulls and black-crowned night herons in the Hudson–Raritan Estuary and Black-Crowned Night Herons in the Hudson-Raritan Estuary

    USGS Publications Warehouse

    Grasman, Keith A.; Echols, Kathy R.; May, Thomas M.; Peterman, Paul H.; Gale, Robert W.; Orazio, Carl E.

    2013-01-01

    Previous studies have shown inexplicable declines in breeding waterbirds within western New York/New Jersey Harbor between 1996 and 2002 and elevated polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs) in double-crested cormorant (Phalacrocorax auritus) eggs. The present study assessed associations between immune function, prefledgling survival, and selected organochlorine compounds and metals in herring gulls (Larus argentatus) and black-crowned night herons (Nycticorax nycticorax) in lower New York Harbor during 2003. In pipping gull embryos, lymphoid cells were counted in the thymus and bursa of Fabricius (sites of T and B lymphocyte maturation, respectively). The phytohemagglutinin (PHA) skin response assessed T cell function in gull and heron chicks. Lymphocyte proliferation was measured in vitro in adult and prefledgling gulls. Reference data came from the Great Lakes and Bay of Fundy. Survival of prefledgling gulls was poor, with only 0.68 and 0.5 chicks per nest surviving to three and four weeks after hatch, respectively. Developing lymphoid cells were reduced 51% in the thymus and 42% in the bursa of gull embryos from New York Harbor. In vitro lymphocyte assays demonstrated reduced spontaneous proliferation, reduced T cell mitogen-induced proliferation, and increased B cell mitogen-induced proliferation in gull chicks from New York Harbor. The PHA skin response was suppressed 70 to 80% in gull and heron chicks. Strong negative correlations (r?=?–0.95 to –0.98) between the PHA response and dioxins and PCBs in gull livers was strong evidence suggesting that these chemicals contribute significantly to immunosuppression in New York Harbor waterbirds.

  3. Growth and behavioral effects of early postnatal chromium and manganese exposure in herring gull (Larus argentatus) chicks.

    PubMed

    Burger, J; Gochfeld, M

    1995-04-01

    Organisms in marine environments are exposed to chromium and manganese, yet little is known of the effects of these metals on physiology and behavior. In this article we examine the effects of chromium and manganese on early neurobehavioral development in herring gulls, Larus argentatus. Each of 36 2-day-old herring gull chicks was randomly assigned to one of three treatment groups to receive either chromium nitrate (25 mg/kg), manganese acetate (50 mg/kg), or a control dose of sterile saline solution. The trios were not siblings, but were matched by age and weight. Behavioral tests examined food-begging, balance, locomotion, righting response, recognition, thermoregulation, and perception. There were significant differences in begging behavior by 5 days postinjection, and there were significant differences in weight gain throughout development until 50 days of age, when the experiment was terminated. Behavioral tests, administered from 18-48 days postinjection, indicated significant differences between control and the exposed groups for time to right themselves; thermoregulation behavior; and performance on a balance beam, inclined plane, actual cliff, and visual cliff (although not all components varied significantly). Of the 14 behavioral measures with significant differences, control birds performed best on 12. PMID:7617708

  4. Sensitivity of embryos from duck, goose, herring gull, and various chicken breeds to 3,3',4,4'-tetrachlorobiphenyl.

    PubMed

    Brunström, B

    1988-01-01

    Yolks in embryonated eggs from duck, goose, herring gull, and various breeds of chicken were injected with 3,3',4,4'-tetrachlorobiphenyl (TCB). Hens' eggs were injected after 4 days of incubation and eggs from the other species were injected after 5 days of incubation. All breeds of chicken tested were very sensitive to TCB. At a dose of 20 micrograms/kg egg the death rate in chick embryos ranged from 70 to 100% at the end of the experiment by Day 18 of incubation. Liver lesions, hydropericardium, subcutaneous edema, shortened beak, and microphthalmia were found in both dead and living TCB-treated chick embryos. Embryos of the other species tested were considerably less sensitive than chick embryos to TCB. The highest dose administered to these species was 5,000 micrograms/kg egg for ducks and 1,000 micrograms/kg egg for geese and herring gulls. These doses did not affect the viability of the embryos and caused no gross abnormalities. PMID:3131755

  5. Evidence of weak contaminant-related oxidative stress in glaucous gulls (Larus hyperboreus) from the Canadian Arctic.

    PubMed

    Wayland, Mark; Hoffman, David J; Mallory, Mark L; Alisauskas, Ray T; Stebbins, Katherine R

    2010-01-01

    Environmental contaminants are transported over great distances to Arctic ecosystems, where they can accumulate in wildlife. Whether contaminant concentrations in wildlife are sufficient to produce adverse effects remains poorly understood. Exposure to contaminants elevates oxidative stress with possible fitness consequences. The glaucous gull (Larus hyperboreus), an Arctic top predator, was used as a bioindicator for investigating relationships between contaminant levels (organochlorines and polychlorinated biphenyls [OC/PCB], mercury [Hg], and selenium [Se]) and measures of oxidative stress (glutathione [GSH] metabolism and lipid peroxidation) in Canadian Arctic ecosystems. Contaminant levels were low and associations between contaminant exposure and oxidative stress were weak. Nevertheless, glutathione peroxidase activity rose with increasing hepatic Se concentrations, levels of thiols declined as Hg and OC/PCB levels rose, and at one of the two study sites levels of lipid peroxidation were elevated with increasing levels of hepatic Hg. These results suggest the possibility of a deleterious effect of exposure to contaminants on gull physiology even at low contaminant exposures. PMID:20526953

  6. Pinpointing potential causative agents in mixtures of persistent organic pollutants in observational field studies: a review of glaucous gull studies.

    PubMed

    Bustnes, Jan O

    2006-01-01

    Since different organochlorine contaminants (OCs) are often highly correlated in biota, a major challenge in observational field studies is to establish whether some OCs are potentially important causative agents of adverse effects. A possible solution to this problem is to compare the strength of the effects of different OCs on a number of outcome parameters, and then examine if some compounds are more consistently reliable predictors of adverse effects. In this analysis the four most common OCs (hexachlorobenzene [HCB], oxychlordane, p,p'-dichlorodiphenyldichloroethylene [DDE], and polychlorinated biphenyls [PCBs]) in arctic glaucous gulls (Larus hyperboreus) were ranked in relation to 19 different outcome parameters, for which at least 1 of the 4 OCs were significantly related. PCBs, made up close to 75% of the measured sigmaOCs, DDE 17-18%, and HCB and oxychlordane 3-4%, respectively. Despite relatively low levels of oxychlordane and HCB, these compounds tended to be more reliable predictors of adverse effects and were ranked highest for 11 and 10 of the 19 outcome parameters, respectively. PCBs and DDE were only ranked highest for seven of the outcome parameters. Oxychlordane, HCB, DDE, and PCB were "not significant" two, six, six, and eight times, respectively. Oxychlordane was significantly more likely to be related to adverse effects than DDE. Even if effects of OCs may depend on a complex interaction between different compounds, this analysis indicates that adverse effects are more likely to occur in glaucous gulls with relatively high concentrations of oxychlordane and HCB. PMID:16291564

  7. Variation in immune parameters and disease prevalence among Lesser Black-backed Gulls (Larus fuscus sp.) with different migratory strategies.

    PubMed

    Arriero, Elena; Müller, Inge; Juvaste, Risto; Martínez, Francisco Javier; Bertolero, Albert

    2015-01-01

    The ability to control infections is a key trait for migrants that must be balanced against other costly features of the migratory life. In this study we explored the links between migration and disease ecology by examining natural variation in parasite exposure and immunity in several populations of Lesser Black-backed Gulls (Larus fuscus) with different migratory strategies. We found higher activity of natural antibodies in long distance migrants from the nominate subspecies L.f.fuscus. Circulating levels of IgY showed large variation at the population level, while immune parameters associated with antimicrobial activity showed extensive variation at the individual level irrespective of population or migratory strategy. Pathogen prevalence showed large geographical variation. However, the seroprevalence of one of the gull-specific subtypes of avian influenza (H16) was associated to the migratory strategy, with lower prevalence among the long-distance migrants, suggesting that migration may play a role in disease dynamics of certain pathogens at the population level. PMID:25679797

  8. Effect of reduced food intake on toxicokinetics of halogenated organic contaminants in herring gull (Larus argentatus) chicks.

    PubMed

    Routti, Heli; Helgason, Lisa Bjørnsdatter; Arukwe, Augustine; Wolkers, Hans; Heimstad, Eldbjørg Sofie; Harju, Mikael; Berg, Vidar; Gabrielsen, Geir Wing

    2013-01-01

    The aim of the present study was to investigate how contaminant exposure and reduced food intake affect tissue distribution and biotransformation of halogenated organic contaminants (HOCs) in Arctic seabirds using herring gull (Larus argentatus) as a model species. Herring gull chicks were exposed for 44 d to cod liver oil containing a typical mixture of contaminants. Following exposure, food intake was reduced for a one-week period in a subgroup of the chicks. Polyclorinated biphenyls, organochlorine pesticides, and brominated flame retardants, as well as a wide range of hydroxy, methyl sulfone, and methoxy compounds were measured in liver, brain, and plasma samples. Additionally, phase I biotransformation enzyme activities and phase I and II messenger ribonucleic acid (mRNA) expression were investigated in the liver, brain, or both. Both contaminant exposure and reduced food intake had an increasing effect on the concentrations of HOCs and their metabolites. The HOC exposure and reduced food intake also led to increased 7-ethoxyresorufin-O-deethylation (EROD) activity, whereas mRNA expression of the biotransformation enzymes increased only following the reduced food intake. Tissue distribution of HOCs and their metabolites was not affected by either contaminant exposure or reduced food intake. In conclusion, the results indicate that biotransformation capacity and formation of HOC metabolites increase during reduced food intake. This finding supports the hypothesis that reduced food intake increases the susceptibility of Arctic animals to the effects of lipophilic HOCs. PMID:23060285

  9. Galapagos Islands Flyby

    NSDL National Science Digital Library

    Dave Pape

    1994-03-13

    This animation shows the power of computer graphics to explore data in the sense of virtual reality. In this scene, standard tools are applied to fly around the Galapagos Islands and the ocean floor surrounding the islands.

  10. Overwash on Assateague Island

    USGS Multimedia Gallery

    Overwash on Assateague Island. Overwash occurs when waves overtop the main sand dune and redistribute the sand along new patterns. Overwash has contributed to the gradual movement of Assateague Island to the south....

  11. Habitat and nest site selection in the Common Gull Larus canus in southern Poland: significance of man-made habitats for conservation of an endangered species

    Microsoft Academic Search

    Piotr SKÓRKA; Joanna D. WÓJCIK; Tomasz BABIARZ

    2006-01-01

    The Common Gull is a rare and endangered breeding species at inland habitats in Poland as well as in some other countries in Europe. Breeding biology, habitat and nest site selection were studied in this species in southern Poland. Almost all birds nested on industrial water bodies (gravel pits, sedimentation basins), although fishponds and reservoirs were the most abundant habitat

  12. A BIOLOGICAL BATTLE AGAINST THE THOUSANDS OF GARDEN CHAFERS (PHYLLOPERTHA HORTICOLA) THAT ATTRACT LARGE NUMBERS OF GULLS (LARUS SP.) DURING THE SUMMER SEASON AT RYGGE AIR STATION, NORWAY

    Microsoft Academic Search

    Christian K. Aas; Thomas Olstad; Ola-Mattis Drageset; Solveig Haukeland; Dag Olav Kleppestø; Bjørn Arne Rukke

    Seven-eight years ago we first observed very large numbers of Garden Chafers (Phyllopertha horticola) swarming at Rygge Air Station in June and July, attracting large numbers of Black-headed - (Larus ridibundus) and Common Gulls (Larus canus) feeding on these flying beetles. Every summer season since then the Garden Chafers have been present, although in a smaller number in most recent

  13. Microhabitat Analysis of Bass Tapeworm, Proteocephalus ambloplitis (Eucestoda: Proteocephalidae), in Smallmouth Bass, Micropterus dolomieu, and Largemouth Bass, Micropterus salmoides, from Gull Lake, Michigan, U.S.A

    Microsoft Academic Search

    Merritt G. Gillilland; Patrick M. Muzzall

    2004-01-01

    A total of 142 bass (54 Micropterus dolomieu and 88 Micropterus salmoides) were collected April through September 2000 and April through July 2001 from 5 locations in Gull Lake, Michigan, U.S.A., and examined for Proteocephalus ambloplitis. Proteocephalus ambloplitis was 100% prevalent in both smallmouth and largemouth bass. The numbers of P. ambloplitis from each microhabitat (gonads, liver, spleen, mesentery, pyloric

  14. Anatomy and histochemistry of spread-wing posture in birds. 2. Gliding flight in the California gull, Larus californicus: a paradox of fast fibers and posture.

    PubMed

    Meyers, R A; Mathias, E

    1997-09-01

    Gliding flight is a postural activity which requires the wings to be held in a horizontal position to support the weight of the body. Postural behaviors typically utilize isometric contractions in which no change in length takes place. Due to longer actin-myosin interactions, slow contracting muscle fibers represent an economical means for this type of contraction. In specialized soaring birds, such as vultures and pelicans, a deep layer of the pectoralis muscle, composed entirely of slow fibers, is believed to perform this function. Muscles involved in gliding posture were examined in California gulls (Larus californicus) and tested for the presence of slow fibers using myosin ATPase histochemistry and antibodies. Surprisingly small numbers of slow fibers were found in the M. extensor metacarpi radialis, M. coracobrachialis cranialis, and M. coracobrachialis caudalis, which function in wrist extension, wing protraction, and body support, respectively. The low number of slow fibers in these muscles and the absence of slow fibers in muscles associated with wing extension and primary body support suggest that gulls do not require slow fibers for their postural behaviors. Gulls also lack the deep belly to the pectoralis found in other gliding birds. Since bird muscle is highly oxidative, we hypothesize that fast muscle fibers may function to maintain wing position during gliding flight in California gulls. PMID:9259122

  15. Henderson Island, Pacific Ocean

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Henderson Island (24.5S, 128.5W) Pacific Ocean southeast of the Tuamotu Archipelago, is a good example of the many barren islands that but for lack of a source of water could be another lush tropical paradise. The crew of HMS Bounty, in searching for a refuge, sailed past this island but rejected it in favor of nearby Pitcairn Island because of the lack of resources and water.

  16. Falkland Islands, UK

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This view of the Falkland Islands (52.0S, 58.5W) was taken with a dual camera mount. Compare this scene with STS048-109-043 to analyze the unique properties of each film type. Seldom seen cloud free, the Falkland Islands lie off the southern coast of Argentina. The cold Falklands Ocean Current keeps the islands chilly, ideal for sheep herding and fishing, the two main industries. Colonies of seals and penguins also thrive on the islands.

  17. Arctic ice islands

    SciTech Connect

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  18. Island Fox Paradox

    NSDL National Science Digital Library

    Sharon Levy (Freelancer; )

    2010-05-03

    Channel Island foxes, long the top predator in their ecosystem, show little fear of humans. Wild foxes often accost visitors on San Nicolas, the island with the most abundant fox population in the island chain. Now, archaeologists have new evidence that suggests foxes were carried to the islands by indigenous people thousands of years ago, and that humans shaped the evolution of the entire species. Do species introduced by native people thousands of years ago deserve protection?

  19. Islands in Amazonia

    Microsoft Academic Search

    G. T. Prance

    1996-01-01

    There are a number of habitats within the lowland Amazonian rainforest ecosystem that are functional islands. Those that are discussed are savannas, white sand campinas and caatingas, inselbergs and sandstone table mountains or tepuis. Each of these habitats is a series of isolated islands of vegetation and in some cases speciation has taken place between islands, especially the older tepuis,

  20. Overwash on Assateague Island

    USGS Multimedia Gallery

    Overwash on Assateague Island. When waves wash over the main sand dune on the island, that creates a phenomenon called overwash, where the sand is moved along the path of the wave. Overwash has contributed to the gradual movement of Assateague Island to the south....

  1. Diomede Islands, Bering Straight

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Diomede Islands consisting of the western island Big Diomede (also known as Imaqliq, Nunarbuk or Ratmanov Island), and the eastern island Little Diomede (also known as Krusenstern Island or Inaliq), are two rocky islands located in the middle of the Bering Strait between Russia and Alaska. The islands are separated by an international border and the International Date Line which is approximately 1.5 km from each island; you can look from Alaska into tomorrow in Russia. At the closest land approach between the United States, which controls Little Diomede, and Russia, which controls Big Diomede, they are 3 km apart. Little Diomede Island constitutes the Alaskan City of Diomede, while Big Diomede Island is Russia's easternmost point. The first European to reach the islands was the Russian explorer Semyon Dezhnev in 1648. The text of the 1867 treaty finalizing the sale of Alaska uses the islands to designate the border between the two nations.

    The image was acquired July 8, 2000, covers an area of 13.5 x 10.8 km, and is located at 65.8 degrees north latitude, 169 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  2. How Are Islands Formed?

    NSDL National Science Digital Library

    2001-01-01

    This lesson provides students with information about how islands are formed, including a basic knowledge of plate tectonics. Using the islands of Hawaii as an example, students learn about the earth processes that cause the formation of islands over time, including volcanoes and hot spots.

  3. Avifauna: Turnover on Islands

    Microsoft Academic Search

    Ernst Mayr

    1965-01-01

    The percentage of endemic species of birds on islands increases with island area at a double logarithmic rate. This relation is apparently due to extinction, which is more rapid the smaller the island. The turnover resulting from extinction and replacement appears to be far more rapid than hitherto suspected.

  4. Drowning of an ooid shoal: Mississippian Greenbrier Limestone near West Virginia dome

    SciTech Connect

    Carney, C. (Wright State Univ., Dayton, OH (USA))

    1989-08-01

    The depositional setting for the Greenbrier Limestone of the central Appalachian basin included a continually subsiding basin, centered in southeastern West Virginia and adjacent Virginia, separated by a hinge zone from a broad shallow shelf located to the north and northwest. Oolitic limestones are thick and extensive in southern West Virginia; however, most of these units thin drastically and change in lithology to the north. An area of uplift, the West Virginia dome, developed along the hinge zone in north-central West Virginia. During early Greenbrier deposition, this area was exposed as an island. Later, the dome was submerged but remained as a submarine high throughout Greenbrier sedimentation. The northernmost occurrences of Mississippian oolitic limestones in West Virginia surround this feature.

  5. Concentrated nesting of mallards and gadwalls on Miller Lake Island, North Dakota

    USGS Publications Warehouse

    Duebbert, H.F.; Lokemoen, J.T.; Sharp, D.E.

    1983-01-01

    Island-nesting mallards (Anas platyrhynchos) and gadwalls (A. strepera) were studied on a 4.5-ha island in 385-ha Miller Lake in northwestern North Dakota during 1976-80. During the 5-year study, 2,561 duck nests of 9 species were found on Island A located 180 m offshore; 59% were mallard and 34% were gadwall. In patches of shrub cover, which contained the greatest concentrations of nests, densities ranged from 241 to 389 mallard nests/ha and from 139 to 237 gadwall nests/ha. Over 97% of the nests were placed in 4 patches of shrubs totaling about 1 ha of western snowberry (Symphoricarpos occidentalis)--Woods rose (Rosa woodsii) cover, which composed about 30% of the island's vegetation. Average hatching success was 85% for clutches of all species. Abandonment averaged 14% (348 of 2,426 nests) and was the major cause of egg failure. Only 15 nests (<1%) were destroyed, primarily by ring-billed (Larus delawarensis) or California gulls (L. californicus). A minimum of 15,960 ducklings including 9,300 mallards and 5,150 gadwalls hatched on 4.5-ha Island A. Hatching rates of eggs in successful nests averaged 83% for mallards and 87% for gadwalls. Despite the close spacing of nests, most individual hens maintained normal nesting regimes. Eighty-one percent of the mallard clutches contained 7-13 eggs and 81% of the gadwall clutches contained 8-14 eggs. Island A in Miller Lake provides an outstanding example of the potential for high reproduction levels of mallards and gadwalls nesting in small areas of predator-free habitats.

  6. Long-term coral community records from Lugger Shoal on the terrigenous inner-shelf of the central Great Barrier Reef, Australia

    NASA Astrophysics Data System (ADS)

    Perry, C. T.; Smithers, S. G.; Johnson, K. G.

    2009-12-01

    Long-term (millennial timescale) records of coral community structure can be developed from the analysis of corals preserved in radiometrically dated reef cores. Here, we present such a record (based on six cores) from Lugger Shoal, a turbid zone, nearshore reef on the inner-shelf of the central Great Barrier Reef. Lugger Shoal initiated growth ~800 cal yBP. It is constructed of large in situ Porites bommies, between which a framework of coral rubble (dominated by Acropora pulchra, Montipora mollis, Galaxea fascicularis and Cyphastrea serailia) has accumulated. Reef accretion occurred under conditions of net long-term fine-grained, terrigenous sediment accumulation, and with a coral community dominated throughout by a consistent, but low diversity, suite of coral taxa. This dataset supports recent suggestions that nearshore coral communities that establish themselves under conditions that are already close to the thresholds for coral survival may be resilient to water quality deteriorations associated with human activities.

  7. Whole blood concentrations of organochlorines as a dose metric for studies of the glaucous gull (Larus hyperboreus).

    PubMed

    Bustnes, J O; Skaare, J U; Erikstad, K E; Bakken, V; Mehlum, F

    2001-05-01

    In order to examine if whole blood concentrations of organochlorines (OCs) is an appropriate dosimetric parameter for use in ecotoxicological studies of free-living birds, a number of incubating glaucous gulls (Larus hyperboreus) were repeatedly sampled within and between subsequent breeding seasons. The wet weight concentrations of selected OCs, differing in persistence and fat solubility, were compared and it was assessed to what extent present concentrations could be predicted from concentrations previously measured in the individuals. There were only a few significant differences in the blood concentrations of the selected OCs within and between seasons. The most persistent compound, polychlorinated biphenyl (PCB)-153, showed a low interindividual variability, and between seasons, 70% of the variance could be explained by the level in the previous year, while changes in body condition and blood lipid percentage were of less importance. For PCB-101, the predictability of the present blood concentration from the previous concentration was lower than for PCB-153, and changes in body condition and blood lipid percentage explained a higher proportion of the variance. The present level of alpha-hexachlorocyclohexane (HCH) could not be predicted from the previous level. Sex did not explain any significant proportion of the variance in OC concentrations when previous level and changes in body mass and blood lipid were included in the statistical models. Thus, for the most persistent OCs, concentration in the blood of incubating glaucous gulls is representative for the interindividual differences over time and whole blood concentrations of OCs appear adequate as a dose metric in ecotoxicological studies. PMID:11337867

  8. Brominated flame retardants in glaucous gulls from the Norwegian Arctic: more than just an issue of polybrominated diphenyl ethers.

    PubMed

    Verreault, Jonathan; Gebbink, Wouter A; Gauthier, Lewis T; Gabrielsen, Geir W; Letcher, Robert J

    2007-07-15

    Several, unregulated, current-use brominated flame retardants (BFRs), including hexabromobenzene (HBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), and hexabromocyclododecane (as total-(alpha)-HBCD), were examined in egg yolk and plasma of male and female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Also examined were BDE209 and 38 tri- to nona-BDE congeners and brominated biphenyl (BB) 101. The HBB, BTBPE, PBEB, and PBT had high detection frequencies and variability in male and female plasma and egg yolk samples, and their concentrations ranged from nondetectable (< 0.02-0.27 ng/g wet wt) to 2.64 ng/g wet wt. The detection frequencies and range of concentrations of non-BDE BFRs were generally highest in plasma of males relative to females. Total-(alpha)-HBCD concentrations were highest among the non-PBDE BFRs (up to 6.12 and 63.9 ng/g wet wt in plasma and egg yolk, respectively). Next highest was HBB with concentrations within a range comparable to the minor PBDEs monitored (e.g., BDE28, 116 and 155). Sum (sigma)38PBDE concentrations ranged from 2.49 to 54.5 ng/g wet wt in plasma and 81.2 to 321 ng/g wet wt in egg yolk. The BDE209 was virtually nondetectable, whereas six octa-BDEs (i.e., BDE196, 197, 201, 202, 203, and 205), as well as three nona-BDEs (i.e., BDE206, 207, and 208, and potential BDE209 debromination products) were found sporadically in plasma and egg yolk. The results from this study suggestthat in addition to PBDEs, several current-use, non-BDE BFRs undergo long-range atmospheric transport and bioaccumulate at low levels in and are maternally transferred (to eggs) in glaucous gulls from the Norwegian Arctic. PMID:17711204

  9. The toxic effects of multiple persistent organic pollutant exposures on the post-hatch immunity maturation of glaucous gulls.

    PubMed

    Sagerup, Kjetil; Larsen, Hans Jørgen S; Skaare, Janneche Utne; Johansen, Grethe M; Gabrielsen, Geir Wing

    2009-01-01

    This study tested whether the immune system of the glaucous gull (Larus hyperboreus) chicks became affected by existing environmental contaminants. An experimental group was given food that mimicked the natural contaminant mixture found in food from the North Atlantic marine environment, while the control group was given the equivalent of nearly clean food. All chicks were immunized with herpes virus (EHV), reovirus (REO), influenza virus (EIV), and tetanus toxoid (TET) in order to test their ability to respond to foreign specific antigens. At 8 wk, the experimental group had 3- to 13-fold higher concentrations of hexachlorobenzene (HCB), oxychlordane, p,p'-DDE, and total polychlorinated biphenyls (Sigma PCB) than did the control. The experimental group produced significantly lower antibody titer against EIV and had lower concentrations of immunoglobulin-G (IgG) and -M (IgM) in blood. Hematocrit percent and leukocyte numbers did not differ between the two groups. The ability of lymphocytes to proliferate in vitro was tested with three mitogens, phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM), and three antigens, keyhole limpet hemocyanin (KLH), TET, and Mycobacterium avium subsp. paratuberculosis tuberculin purified protein derivative (PPD). The experimental group had a significantly higher peripheral blood lymphocyte response to PHA and to spleen lymphocytes in vitro stimulated with Con A and PCB congeners 99 or 153, while the Con A, PWM, KLH, TET, PPD, and Con A plus PCB-156 or -126 showed nonsignificant differences between groups. Data indicate that the combined effect of multiple persistent organic pollution exposures occurring naturally in the Arctic negatively affect the immune system of the glaucous gull chick. PMID:19557615

  10. Perfluorinated alkyl substances in plasma, liver, brain, and eggs of glaucous gulls (Larus hyperboreus) from the Norwegian arctic.

    PubMed

    Verreault, Jonathan; Houde, Magali; Gabrielsen, Geir W; Berger, Urs; Haukås, Marianne; Letcher, Robert J; Muir, Derek C G

    2005-10-01

    Recent environmental surveys have ascertained the widespread occurrence of perfluorinated alkyl substances (PFAS) in tissues of wildlife from the Arctic. In the present study, we investigated the distribution of a suite of PFAS in plasma, liver, brain, and egg samples from adult glaucous gulls (Larus hyperboreus), an apex scavenger-predator seabird breeding in the Norwegian Arctic. Perfluorooctane sulfonate (PFOS) was the predominant PFAS in all samples and was present at concentrations that are the highest reported thus far in any arctic seabird species and populations. Among the body compartment/ tissue samples analyzed, PFOS was highest in plasma (48.1-349 ng/g wet weight (ww)), followed by liver approximately equal to egg > brain. Perfluorocarboxylic acids (PFCAs) with 8-15 carbon (C) atoms were found, with the highest concentrations determined in plasma (sum PFCA: 41.8-262 ng/g ww), whereas 5C- and 6C-PFCAs were below the limits of detection. Perfluorobutane sulfonate, perfluorooctane sulfonamide, and four saturated (8:2 FTCA and 10:2 FTCA) and unsaturated (8:2 FTUCA and 10:2 FTUCA) fluorotelomer carboxylic acids were not detected in any samples. Perfluorohexane sulfonate was measured at concentrations up to 2.71 ng/g ww. The accumulation profiles of PFCAs were characterized by high proportions of the long and odd-numbered carbon-chain-length compounds, namely perfluoroundecanoic (11C) and perfluorotridecanoic acid (13C), although their individual contribution differed between the matrixes analyzed. Current PFAS concentrations suggest a bioaccumulation potential in Norwegian arctic glaucous gulls that needs to be assessed as part of a broad organohalogen contaminant cocktail with potential for mediating biological processes in this vulnerable top-predator marine species. PMID:16245813

  11. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been made. Petrophysical and engineering property characterization is progressing. Data on reservoir production rate and pressure history at Appleton and Vocation Fields have been tabulated, and porosity data from core analysis has been correlated with porosity as observed from well log response. Data integration is on schedule, in that, the geological, geophysical, petrophysical and engineering data collected to date for Appleton and Vocation Fields have been compiled into a fieldwide digital database for reservoir characterization, modeling and simulation for the reef and carbonate shoal reservoirs for each of these fields.

  12. The Flores Island tsunamis

    Microsoft Academic Search

    Harry Yeh; Fumihiko Imamura; Costas Synolakis; Yoshinobu Tsuji; Philip Liu; Shaozhong Shi

    1993-01-01

    On December 12, 1992, at 5:30 A.M. GMT, an earthquake of magnitude Ms 7.5 struck the eastern region of Flores Island, Indonesia (Figure 1), a volcanic island located just at the transition between the Sunda and Banda Island arc systems. The local newspaper reported that 25-m high tsunamis struck the town of Maumere, causing substantial casualties and property damage. On

  13. Environmental assessment on industrial cogeneration demonstration plant at the Riegel Textile Mill site, Ware Shoals, South Carolina

    SciTech Connect

    Not Available

    1981-06-01

    The paper examines the potential environmental, health and safety, and socioeconomic impacts of the proposed industrial cogeneration demonstration plant at the Riegel Textile Corporation's mill in Ware Shoals, South Carolina. The proposal involves installing and demonstrating cogeneration of process steam and electricity by topping process steam. Section I discusses the need and purpose for the proposal. Section II discusses alternatives including the proposed action. Alternatives including the proposed cogeneration system discussed are no action; replacement of one existing boiler, omitting cogeneration; system alternatives (cogeneration bottoming cycles, alternative cogeneration topping cycles. Section III provides past and present data on those aspects of the local environment which could be affected by the proposed actions. Items discussed are topography and climatology, geology and oils; air quality; water resources and quality; ecological resources; land use plans and policies; socioeconomic setting; health and safety; utilities and services; energy resources; cultural resources and aesthetics and details on these items are presented in Section IV. A summary of impacts associated with, impact of alternatives to, and mitigating measures to the proposed action are also presented in Section IV. Discussions on unavoidable adverse environmental effects; irreversible and irretrievable commitment of resources; relationship of land use plans, policies, and controls; and relationship between short-term use of environment and maintenance and enhancement of long-term productivity conclude Section IV. (MCW)

  14. Individually assessed boldness predicts Perca fluviatilis behaviour in shoals, but is not associated with the capture order or angling method.

    PubMed

    Kekäläinen, J; Podgorniak, T; Puolakka, T; Hyvärinen, P; Vainikka, A

    2014-11-01

    Selectivity of recreational angling on fish behaviour was studied by examining whether capture order or lure type (natural v. artificial bait) in ice-fishing could explain behavioural variation among perch Perca fluviatilis individuals. It was also tested if individually assessed personality predicts fish behaviour in groups, in the presence of natural predators. Perca fluviatilis showed individually repeatable behaviour both in individual and in group tests. Capture order, capture method, condition factor or past growth rate did not explain variation in individual behaviour. Individually determined boldness as well as fish size, however, were positively associated with first entrance to the predator zone (i.e. initial risk taking) in group behaviour tests. Individually determined boldness also explained long-term activity and total time spent in the vicinity of predators in the group. These findings suggest that individual and laboratory-based boldness tests predict boldness of P. fluviatilis in also ecologically relevant conditions, i.e. in shoals and in the presence of natural predators. The present results, however, also indicate that the above-mentioned two angling methods may not be selective for certain behavioural types in comparison to each other. PMID:25270290

  15. Dynamics of seabird colonies vulnerable to sea-level rise at French Frigate Shoals, Hawai`i

    USGS Publications Warehouse

    Reynolds, Michelle H.; Courtot, Karen N.; Krause, Crystal M.; Seavy, Nathaniel E.; Hartzell, Paula; Hatfield, Jeff S.

    2013-01-01

    and habitat creation may mitigate projected seabird population declines due to habitat loss. We predict substantial losses in seabird nesting habitat across the low-lying Hawaiian Islands by 2100 and emphasize the need to restore higher elevation seabird colonies.

  16. Ober's Island, One of the Review Islands on Rainy Lake, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Ober's Island, One of the Review Islands on Rainy Lake, bounded on the south by The Hawk Island and on the north by The Crow Island. These islands are located seven miles east of Ranier, Minnesota, three miles west of Voyageur National Park, and one mile south of the international border of the United States of America and Canada. The legal description of Mallard Island is Lot 6, Section 19, T-17-N, R-22-W, Koochiching County, Minnesota, Ranier, Koochiching County, MN

  17. Hydrologic data for Block Island, Rhode Island

    USGS Publications Warehouse

    Burns, Emily

    1993-01-01

    This report was compiled as part of a study to assess the hydrogeology and the quality and quantity of fresh ground water on Block Island, Rhode Island. Hydrologic data were collected on Block Island during 1988-91. The data are pre- sented in illustrations and tables. Data collec- ted include precipitation, surfae-water, ground- water, lithologic, and well-construction and dis- charge information. Precipitation data include total monthly precipitation values from 11 rain gages and water-quality analyses of 14 precipi- tation samples from one station. Surface-water data include water-level measurements at 12 ponds, water-quality data for five ponds, and field specific-conductance measurements at 56 surface- water sites (streams, ponds, and springs). Ground- water data include water-level measurements at 159 wells, water-quality data at 150 wells, and field specific-conductance data at 52 wells. Lithologic logs for 375 wells and test borings, and construc- tion and location data for 570 wells, springs, and test borings are included. In addition, the data set contains data on water quality of water samples, collected by the Rhode Island Department of Health during 1976-91, from Fresh and Sands Ponds and from wells at the Block Island Water Company well field north of Sands Pond.

  18. Contaminant Residues in Tissues of Adult and Prefledged Herring Gulls from the Great Lakes in Relation to Diet in the Early 1990s

    Microsoft Academic Search

    Glen A. Fox; Keith A. Grasman; Keith A. Hobson; Kim Williams; Deborah Jeffrey; Barbara Hanbidge

    2002-01-01

    In the early 1990s, herring gulls (Larus argentatus) were collected in 15 breeding colonies throughout the Great Lakes basin and in two reference colonies on Lake Winnipeg and the Bay of Fundy. Organochlorine and metal concentrations, and stable isotope ratios (15N\\/14N and 13C\\/12C) were measured in their tissues, and we qualitatively assessed their diet. Breast muscle ?15N suggested that adults

  19. Age, sex and spatial dependent variations in heavy metals levels in the Glaucous Gulls ( Larus hyperboreus ) from the Bjørnøya and Jan Mayen, Arctic

    Microsoft Academic Search

    Micha? Malinga; Piotr Szefer; Geir W. Gabrielsen

    2010-01-01

    Heavy metals (Cd, Cu, Fe, Mn and Zn) concentrations were determined in different tissues (muscle, kidney, liver, brain, gonads,\\u000a heart and feathers) of Glaucous Gulls (Larus hyperboreus) from Bjørnøya and Jan Mayen. The age and spatial dependent variations in heavy metals were quantified and interpreted in\\u000a view of the three chemometric techniques, i.e. non-parametric Mann–Whitney U test, redundancy gradient analysis

  20. Do night-active birds lack daily melatonin rhythms? A case study comparing a diurnal and a nocturnal-foraging gull species

    Microsoft Academic Search

    Martin Wikelski; Elisa M. Tarlow; Corine M. Eising; Ton G. G. Groothuis; Ebo Gwinner

    2006-01-01

    Plasma melatonin concentrations in most animals investigated so far increase at night regardless of whether individuals are\\u000a day or night active. Nevertheless, daily melatonin amplitudes are often seasonally adjusted to ecological conditions, with\\u000a birds that breed at high latitudes and migrate during the night showing lower daily amplitudes. Here we investigate whether\\u000a nocturnal seabirds, gulls that feed at night, also

  1. Marine and Island Ecology.

    ERIC Educational Resources Information Center

    Stephens, Lawrence J.; And Others

    1988-01-01

    Describes an ecology course which provides students with an opportunity to observe aquatic and terrestrial life in the Bahamas. States that students learn scientific methodology by measuring physical and chemical aspects of the island habitats. Provides information on the island, course description and objectives, transportation, facilities, and…

  2. 75 FR 51098 - Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, Island, San Juan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ...Wildlife Service [FWS-R1-R-2010-N131; 1265-0000-10137-S3] Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, Island, San Juan, Skagit, and Whatcom Counties, WA AGENCY: Fish and Wildlife...

  3. Impact of changes in analytical techniques for the measurement of polychlorinated biphenyls and organochlorine pesticides on temporal trends in herring gull eggs.

    PubMed

    de Solla, Shane R; Weseloh, D V Chip; Hebert, Craig E; Pekarik, Cynthia

    2010-07-01

    Changes in analytical approaches during the tenure of monitoring programs for organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) may affect estimates of temporal trends. We used an in-house reference material to create multiplication factors to adjust the estimates of OC pesticides and PCBs (Aroclor equivalents) in Great Lake herring gull eggs analyzed using electron capture detection (1987-1997) to be more equivalent to estimates using mass spectrometric detection (1998-2005) as well as accompanying differences in analytical procedures. We examined temporal trends in contaminant concentrations in herring gull eggs using change point regressions, to determine whether significant changes in long-term trends were associated with analytical methodology. The highest frequency of change point occurrences shifted from 1997 (when analytical methodology was altered) to 2003 after data adjustment. The explanatory power (r2) of the regressions was lower after adjustment, although only marginally so (mean r2 difference=0.04). The initial rates of decline before change points in contaminant concentrations were generally slower after the data adjustment, but after any change points the declines were not significantly different. The regression models did not change for 83.3% of the cases. The effects on the interpretation of long-term temporal trends in herring gull eggs, although not negligible, were minor relative to the magnitude of the temporal changes. PMID:20821596

  4. Age, sex and spatial dependent variations in heavy metals levels in the Glaucous Gulls (Larus hyperboreus) from the Bjørnøya and Jan Mayen, Arctic.

    PubMed

    Malinga, Micha?; Szefer, Piotr; Gabrielsen, Geir W

    2010-10-01

    Heavy metals (Cd, Cu, Fe, Mn and Zn) concentrations were determined in different tissues (muscle, kidney, liver, brain, gonads, heart and feathers) of Glaucous Gulls (Larus hyperboreus) from Bjørnøya and Jan Mayen. The age and spatial dependent variations in heavy metals were quantified and interpreted in view of the three chemometric techniques, i.e. non-parametric Mann-Whitney U test, redundancy gradient analysis and detrended correspondence analysis. The Glaucous Gulls from Bjørnøya contained significantly higher (p < 0.05) levels of Cd, Cu and Zn than those inhabited Jan Mayen. Adult birds were characterized by greater (p < 0.01) concentration of muscle, hepatic and renal heavy metals in comparison to chicks. Insignificantly higher slope constant Zn/Cd for the liver than for the kidney may reflect insignificant Cd exposure. Estimate of transfer factor (TF) allows us to assess variations in heavy metal concentrations during the individual development of Glaucous Gulls. It may be stated that there is a distinct increase of bioaccumulation of all the studied metals during subsequent stages of the bird life. PMID:19847662

  5. Erosion and deterioration of the Isles Dernieres Barrier Island Arc, Louisiana, U.S.A.: 1853 to 1988

    USGS Publications Warehouse

    McBride, Randolph A.; Penland, Shea; Jaffe, Bruce E.; Williams, S. Jeffress; Sallenger, Asbury H., Jr.; Westphal, Karen A.

    1989-01-01

    Using cartographic and aerial photography data from the years 1853, 1890, 1934, 1956, 1978, 1984, and 1988, shoreline change maps of the Isles Dernieres barrier island arc were constructed. These data were accurately superimposed, using a computer mapping system, which removed projection, datum, scale, and other cartographic inconsistencies. Linear, areal, and perimeter measurements indicate that the Isles Dernieres are suffering rapid rates of coastal erosion, land loss, and breakup. Bayside and gulfside erosion, in combination with sediment shortage and subsidence, have caused the Isles Dernieres to narrow through time. In addition, the core of the barrier island arc does not migrate landward and instead, breaks up in place as a result of inlet breaching and development. This is in contrast to other models of landward barrier island migration during transgression. If these trends continue, the Isles Dernieres will likely evolve into a subaqueous inner-shelf shoal by the early 21st century. Loss of the Isles Dernieres barrier island arc will severely impact the Terrebonne parish estuary, resulting in decreased environmental quality and increased public risk from storms and hurricanes.

  6. Intraslope basin reservoirs deposited by gravity-driven processes: Ship shoal and ewing banks areas, offshore Louisiana

    SciTech Connect

    Armentrout, J.M.; Malecek, S.J.; Mathur, V.R. [Mobil Oil Corp., Dallas, TX (United States)] [and others

    1995-06-01

    Seismic facies and high-resolution biostratigraphic analysis provide a sequence stratigraphic framework for interpreting lateral distribution of sand-prone facies and reservoir connectivity in the Ship Shoal 351-358 to Ewing Bank 988 area, offshore Louisiana. The interval of interest is an isochron thick interpreted as a lowstand systems tract deposited at bathyal water depths within an intraslope-basin. This basin is approximately 50 kilometers from the age equivalent shelf/slope break. The D. pentaradiatus-D. brouweri sequence consists of the synclinal fill of a salt withdrawal basin forming an isochron thick that thins onto adjacent salt-cored structural highs. This isochron interval was subdivided into four seismic facies and each is calibrated with local well data. The seismic facies are: Facies (1) hummocky-mounded facies with an internal reflection character of discontinuous variable amplitude, calibrated to thick, flat-based blocky to fining-upward sandstones interpreted as local sheets deposited as channel-fed depositional lobes; Facies (3) clinoform-wedge facies are characterized by continuous, uniform amplitude reflections and are calibrated with mudstones interpreted as part of a downslope prograding complex that downlaps and onlaps the hummocky- mounded facies; and Facies (4) parallel-continuous facies of relatively uniform amplitude correlated with mudstones that drape the other three facies throughout the study area and are interpreted as hemipelagic mudstone. Mapped patterns of these seismic facies suggest a network of channel systems within a slope valley supplying sand by gravity-driven processes into a local salt withdrawal intraslope-basin. Following the above analysis, three wells and two side-tracks were drilled to further test the prospectivity of the area. Rock type and hydrocarbon predictions based on seismic facies analysis were confirmed by the wells.

  7. The Shoal Arm Formation, north-central Newfoundland: Fe- and Mn-enriched sediments underlying black shales and flysch

    SciTech Connect

    Bruechert, V.; Delano, J.W.; Kidd, J.W.; William, S.F. (State Univ. of New York, Albany, NY (United States). Dept. of Geological Sciences)

    1992-01-01

    The Middle Ordovician Shoal Arm Formation is located in the central volcanic belt of north-central Newfoundland and consists of a sequence of hematitic argillites overlain by grey cherts and then black shales directly underneath a late Ordovician/early Silurian flysch sequence. The hematitic argillites are enriched in Fe, Mn, Ni, Pb, and Co. Geochemically definable components within related lithologic groups were discriminated using principal component analysis and factor analysis. These procedures indicate the presence of (1) biogenic, (2) mixed detrital, (3) hydrothermal, and (4) Mn-carbonate components. The base of the hematitic part is marked by a sharp increase in the hydrothermal component, which then decreases stratigraphically upward. The Mn-carbonate component also decreases upwards, but persists up to the grey cherts. The clastic component changes from mixed mafic/pelagic clay-like detritus to Zr-, Nb- and Y-rich detritus in the top hematitic part. The grey cherts mark a transitional stage between the hematitic sediments (oxic) and the black shales (anoxic). The change to increasingly O[sub 2]-deficient conditions is explained by (a) an increase of biological productivity and related O[sub 2]-drain by C[sub org]-oxidation and/or (b) diachronous subsidence of the basin floor into a deep-water anoxic layer as a result of the loading of the basin floor by an approaching thrust stack. The similar stratigraphic sequence and geochemistry of the Middle Ordovician sediments in the Taconic Allochthon of New York State suggest that these processes also acted at other locations along the continental margin of the Iapetus Ocean. This uniformity may reflect the strong influence of the warm Middle Ordovician climate on the sediment facies or, alternatively, the control by the specific tectonic environment.

  8. The shark assemblage at French Frigate Shoals atoll, Hawai'i: species composition, abundance and habitat use.

    PubMed

    Dale, Jonathan J; Stankus, Austin M; Burns, Michael S; Meyer, Carl G

    2011-01-01

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao M(h) ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289-1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling. PMID:21347321

  9. Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment

    PubMed Central

    Marteinson, Sarah C.; Giroux, Jean-François; Hélie, Jean-François; Gentes, Marie-Line; Verreault, Jonathan

    2015-01-01

    Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in ring-billed gulls, thus providing strong support for this long-standing theory in bioenergetics. PMID:26020626

  10. Field Metabolic Rate Is Dependent on Time-Activity Budget in Ring-Billed Gulls (Larus delawarensis) Breeding in an Anthropogenic Environment.

    PubMed

    Marteinson, Sarah C; Giroux, Jean-François; Hélie, Jean-François; Gentes, Marie-Line; Verreault, Jonathan

    2015-01-01

    Environmental and behavioral factors have long been assumed to affect variation in avian field metabolic rate (FMR). However, due to the difficulties in measuring continuous behavior of birds over prolonged periods of time, complete time-activity budgets have rarely been examined in relation to FMR. Our objective was to determine the effect of activity (measured by detailed time-activity budgets) and a series of extrinsic and intrinsic factors on FMR of the omnivorous ring-billed gull (Larus delawarensis). The experiment was conducted during the incubation period when both members of the pair alternate between attending the nest-site and leaving the colony to forage in aquatic and anthropogenic environments (city, agricultural). FMR was determined using the doubly labeled water method. Time-activity budgets were extrapolated from spatio-temporal data (2-5 days) obtained from bird-borne GPS data loggers. Gulls had low FMRs compared to those predicted by allometric equations based on recorded FMRs from several seabird species. Gulls proportioned their time mainly to nest-site attendance (71% of total tracking time), which reduced FMR/g body mass, and was the best variable explaining energy expenditure. The next best variable was the duration of foraging trips, which increased FMR/g; FMR/g was also elevated by the proportion of time spent foraging or flying (17% and 8% of tracking time respectively). Most environmental variables measured did not impact FMR/g, however, the percent of time birds were subjected to temperatures below their lower critical temperature increased FMR. Time-activity budgets varied between the sexes, and with temperature and capture date suggesting that these variables indirectly affected FMR/g. The gulls foraged preferentially in anthropogenic-related habitats, which may have contributed to their low FMR/g due to the high availability of protein- and lipid-rich foods. This study demonstrates that activities were the best predictors of FMR/g in ring-billed gulls, thus providing strong support for this long-standing theory in bioenergetics. PMID:26020626

  11. Ober's Island: The Mallard Ober's Island, One of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Ober's Island: The Mallard - Ober's Island, One of the Review Islands on Rainy Lake, bounded on the south by The Hawk Island and on the north by The Crow Island. These islands are located seven miles east of Ranier, Minnesota, three miles west of Voyageur National Park, and one mile south of the international border of the United States of America and Canada. The legal description of Mallard Island is Lot 6, Section 19, T-17-N, R-22-W, Koochiching County, Minnesota, Ranier, Koochiching County, MN

  12. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    SciTech Connect

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been made. Petrophysical and engineering property characterization has been essentially completed. Porosity and permeability data at Appleton and Vocation Fields have been analyzed, and well performance analysis has been conducted. Data integration is up to date, in that, the geological, geophysical, petrophysical and engineering data collected to date for Appleton and Vocation Fields have been compiled into a fieldwide digital database. 3-D geologic modeling of the structures and reservoirs at Appleton and Vocation Fields has been completed. The model represents an integration of geological, petrophysical and seismic data. 3-D reservoir simulation of the reservoirs at Appleton and Vocation Fields has been completed. The 3-D geologic model served as the framework for the simulations. A technology workshop on reservoir characterization and modeling at Appleton and Vocation Fields was conducted to transfer the results of the project to the petroleum industry.

  13. Conservation Strategy for Sable Island

    E-print Network

    Jones, Ian L.

    Towards a Conservation Strategy for Sable Island Environment Canada, Canadian Wildlife Service, Atlantic Region #12;SABLE ISLAND CONSERVATION STRATEGY page - i March, 1998 A CONSERVATION STRATEGY FOR SABLE ISLAND PREPARED BY This Conservation Strategy for Sable Island was prepared for Environment Canada

  14. Mutagenicity studies on herring gulls from different locations on the Great Lakes. II. Mutagenic evaluation of extracts of herring-gull eggs in a battery of in vitro mammalian and microbial tests.

    PubMed

    Ellenton, J A; McPherson, M F; Maus, K L

    1983-01-01

    Herring-gull (Larus argentatus) eggs were collected from five locations on the Great Lakes and from one colony on the Atlantic coast for organochlorine analysis and mutagenesis testing. The Great Lakes colonies were chosen for their different contaminant levels, while the Atlantic coast colony was used as a relatively clean control. The eggs were homogenized and extracted, and the extracts were tested in the Salmonella/mammalian microsome assay for induction of point mutations and in Chinese hamster ovary (CHO) cells for the induction of sister chromatid exchanges (SCEs) and chromosome aberrations. None of the extracts was mutagenic in Salmonella, either in the presence or absence of metabolic activation. However, all of the extracts, including the clean control, caused significant increases in both the SCE rate and in the number of chromosome aberrations in the CHO cells. There was no apparent relationship between contaminant levels and the magnitude of these responses or the doses at which they occurred, although the chemical analysis indicated a wide range in the concentrations of the different organochlorides present. PMID:6361273

  15. Island Watershed Activity.

    ERIC Educational Resources Information Center

    Benson, Rod

    2003-01-01

    Describes a 90-minute "Island Watershed" activity to help earth science students understand the concept of the water cycle. Introduces a surface waters unit appropriate for students in grades 7-10. Includes watershed project guidelines. (Author/KHR)

  16. Small islands adrift

    NASA Astrophysics Data System (ADS)

    Petherick, Anna

    2015-07-01

    With the charismatic former president of the Maldives, Mohamed Nasheed, behind bars on a widely derided terrorism charge, Anna Petherick asks whether small island states can really make themselves heard in Paris.

  17. The Island Institute

    NSDL National Science Digital Library

    Since 1983, the Island Institute has employed a wide range of individuals, including photographers, artists, policy experts, and others, all in the name of maintaining the viability of the fifteen year-round island communities in the Gulf of Maine. They have become well-known for their outreach efforts, and their website will be of great value to anyone interested in this region, or how various island communities remain economically, culturally, and ecologically sustainable. Resources located on the Institute's homepage include information about fellowship opportunities and links to full and annual reports on the Atlantic herring spawning project. Visitors who are hoping to get a sense of the flavor of this unique region should definitely peruse their monthly publication, "The Working Waterfront." Recent articles include opinion pieces on fish hatcheries, the lobster business, and news profiles of local islanders.

  18. Galveston Island and erosion 

    E-print Network

    Bolleter, Jim Mason

    1985-01-01

    ABSTRACT Galveston Island and Erosion. (May 1985) Jim Mason Bolleter, B. S. , Texas AM University Chairman of Advisory Committee: Dr. A. R. Benton Jr. Mid-term changes in the beach vegetation line on Galveston Island, I as well as the erosional effects... of recent hurri canes and tropical . storms, wer e documented with multi -date aerial photography. While ~ localized accretion has occurred on East Beach due to the shadowing effect of the South Jetty, West beach has fluctuated between erosion Major...

  19. Melville Island, Australia

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Melville Island, just off the coast of Darwin, Northern Territory, Australia (11.5S, 131.0E) is a sparsely inhabited tropical island with heavy woodland concentrations. The widespread and prominant smoke plumes were most likely set to renew pasture under open canopy woodland. Soil erosion is almost non- existant as can be seen by the clear and clean river flow. The offshore sediments are coastal current borne deposits from King Sound to the west.

  20. Exploring plasticity in the wild: laying date-temperature reaction norms in the common gull Larus canus.

    PubMed

    Brommer, Jon E; Rattiste, Kalev; Wilson, Alastair J

    2008-03-22

    Exploration of causal components of plasticity is important for insight into evolutionary dynamics and an organism's ability to respond to climate change. Among individuals, variation in plasticity can be due to genotype-environment interaction (GxE) or a result from environmental effects associated with an individual. We investigated plasticity for laying date in the common gulls Larus canus, using data collected in Estonia during 37 years (n=11624 records on 2262 females, with 472 relatives). We used a sliding window approach to find the period in spring during which mean temperature best explained the annual mean laying date. Then, considering the spring temperature as a quantitative description of the environment, we used pedigree information and a random regression animal model to determine the variation in plasticity for the laying date-temperature relationship. We found that individuals differ in the plasticity of laying date (such that there is increased variation among individuals for the laying date in warmer springs), and that approximately 11% of variation in the laying date is heritable, but we found no statistical support for GxE. Plasticity in this species is not constrained by warmer springs. PMID:18211880

  1. Exploring plasticity in the wild: laying date–temperature reaction norms in the common gull Larus canus

    PubMed Central

    Brommer, Jon E; Rattiste, Kalev; Wilson, Alastair J

    2008-01-01

    Exploration of causal components of plasticity is important for insight into evolutionary dynamics and an organism's ability to respond to climate change. Among individuals, variation in plasticity can be due to genotype–environment interaction (G×E) or a result from environmental effects associated with an individual. We investigated plasticity for laying date in the common gulls Larus canus, using data collected in Estonia during 37 years (n=11?624 records on 2262 females, with 472 relatives). We used a sliding window approach to find the period in spring during which mean temperature best explained the annual mean laying date. Then, considering the spring temperature as a quantitative description of the environment, we used pedigree information and a random regression animal model to determine the variation in plasticity for the laying date–temperature relationship. We found that individuals differ in the plasticity of laying date (such that there is increased variation among individuals for the laying date in warmer springs), and that approximately 11% of variation in the laying date is heritable, but we found no statistical support for G×E. Plasticity in this species is not constrained by warmer springs. PMID:18211880

  2. Morphological studies of the pineal gland in the common gull (Larus canus) reveal uncommon features of pinealocytes.

    PubMed

    Przybylska-Gornowicz, Barbara; Lewçzuk, Bogdan; Prusik, Magdalena; Kalicki, Miroslaw; Zió?kowska, Natalia

    2012-04-01

    The avian pineal is a directly photosensory organ taking part in the organization of the circadian and seasonal rhythms. It plays an important role in regulation of many behavior and physiological phenomena including migration. The aim of the study was to investigate morphology of the pineal organ in the common gull (Larus canus). The light and electron microscopic studies were performed on the pineals of juvenile birds living in natural conditions of the Baltic Sea coast, which have been untreatably injured during strong storms in autumn and qualified for euthanasia. The investigated pineals consisted of a wide, triangular, superficially localized distal part and a narrow, elongated proximal part, attached via the choroid plexus to the intercommissural region of the diencephalon. The accessory pineal tissue was localized caudally to the choroid plexus. Based on the histological criteria, the organ was classified as the solid-follicular type. Two types of cells of fotoreceptory line were distinguished: rudimentary-receptor pinealocytes and secretory pinealocytes. Both types of cells were characterized by unusual features, which have been not previously described in avian pinealocytes: the presence of paracrystalline structures in the basal processes and their endings, the storage of glycogen in the form of large accumulations and the arrangement of mitochondria in clusters. Further studies on other species of wild water birds dwelling in condition of cold seas are necessary to explain if the described features of pinealocytes are specific for genus Larus, family Laridae or a larger group of water birds living in similar environmental conditions. PMID:22262668

  3. Pathology of enteric infections induced by the acanthocephalan Profilicollis chasmagnathi in Olrog's gull, Larus atlanticus, from Argentina.

    PubMed

    La Sala, L F; Perez, A M; Smits, J E; Martorelli, S R

    2013-03-01

    Acanthocephalans can be pathogenic helminths of marine birds. Every year during the breeding season, there is variable mortality among prefledged chicks from the largest known Olrog's gull (Larus atlanticus) colony. Mortality has been associated with infection by the acanthocephalan Profilicollis chasmagnathi. Our aim was to study the role of chicks' size as a risk factor for intensity of infection and severe pathology, and to expand upon previous pathological findings reported in acanthocephalan-infected chicks. Size of the chick was associated with intensity of infection and number of intestinal perforations, which increased by 6.9% and 4.1%, respectively, for each millimetre increment in chick size. Infection was associated with inflammatory enteritis and granulomatous peritonitis. Complete intestinal perforations were observed in 85% and 97.3% of the studied chicks in 2005 and 2006, respectively, and they were observed very early during the post-hatching period. Our results show: (1) the presence of advanced pathology associated with acanthocephalan infections in chicks, beginning very early in the post-hatching period; and (2) significant increases in the intensity of infection and the associated pathology as a function of size of chicks, in dead chicks during this period. PMID:22176660

  4. Biomonitoring of coastal areas in Tunisia: stable isotope and trace element analysis in the Yellow-legged Gull.

    PubMed

    Abdennadher, Aida; Ramírez, Francisco; Romdhane, Mohamed Salah; Ruiz, Xavier; Jover, Lluis; Sanpera, Carolina

    2010-03-01

    We used Yellow-legged Gull (YLG) chicks to monitor trace elements in Tunisian areas subject to different pollution stresses: urban contamination (Chikly), industrial pollution (Thyna) and an unpolluted area (Kneis). We measured trace element concentrations (Hg, Se and Pb) in chick feathers. We also assessed their feeding ecology by analyzing both regurgitates and stable isotopes (SIA) in chick feathers and in their prey, to determine the main entry route of pollutants. SIA revealed that YLG feed mainly on aquatic resources from the Lake of Tunis (Chikly colony) and the Gulf of Gabès (Thyna and Kneis colonies). Moreover, the enriched delta(15)N found in feathers from Chikly are attributed to the eutrophication of the Lake of Tunis. Hg and Se were higher in Kneis and Thyna colonies, in agreement with the higher consumption of marine resources and the greater availability of these elements resulting from the impact of the industrial activity in the area. Pb concentrations were higher in Chikly, related to the heavier traffic around the Lake of Tunis and the use of leaded gasoline. PMID:19896145

  5. Survival, transport, and sources of fecal bacteria in streams and survival in land-applied poultry litter in the upper Shoal Creek basin, southwestern Missouri, 2001-2002

    USGS Publications Warehouse

    Schumacher, John G.

    2003-01-01

    Densities of fecal coliform bacteria along a 5.7-mi (mile) reach of Shoal Creek extending upstream from State Highway 97 (site 3) to State Highway W (site 2) and in two tributaries along this reach exceeded the Missouri Department of Natural Resources (MDNR) standard of 200 col/100 mL (colonies per 100 milliliters) for whole-body contact recreation. A combination of techniques was used in this report to provide information on the source, transport, and survival of fecal bacteria along this reach of Shoal Creek. Results of water-quality samples collected during dye-trace and seepage studies indicated that at summer low base-flow conditions, pastured cattle likely were a substantial source of fecal bacteria in Shoal Creek at the MDNR monitoring site (site 3) at State Highway 97. Using repeat element Polymerase Chain Reaction (rep-PCR), cattle were the presumptive source of about 50 percent of the Escherichia coli (E. coli) isolates in water samples from site 3. Cattle, horses, and humans were the most common presumptive source of E. coli isolates at sites further upstream. Poultry was identified by rep-PCR as a major source of E. coli in Pogue Creek, a tributary in the upper part of the study area. Results of the rep-PCR were in general agreement with the detection and distribution of trace concentrations of organic compounds commonly associated with human wastewater, such as caffeine, the antimicrobial agent triclosan, and the pharmaceutical compounds acetaminophen and thiabendazole (a common cattle anthelmintic). Significant inputs of fecal bacteria to Shoal Creek occurred along a 1.6-mi reach of Shoal Creek immediately upstream from site 3. During a 36-hour period in July 2001, average densities of fecal coliform and E. coli bacteria increased from less than or equal to 500 col/100 mL upstream from this stream reach (sample site 2c) to 2,100 and 1,400 col/100 mL, respectively, at the MDNR sampling site. Fecal bacteria densities exhibited diurnal variability at all five sampling sites along the 5.7-mi study reach of Shoal Creek, but the trends at successive downstream sites were out of phase and could not be explained by simple advection and dispersion. At base-flow conditions, the travel time of bacteria in Shoal Creek along the 5.7-mi reach between State Highway W (site 2) and the MDNR sampling site (site 3) was about 26 hours. Substantial dispersion and dilution occurs along the upper 4.1 mi of this reach because of inflows from a number of springs and tributaries and the presence of several long pools and channel meanders. Minimal dispersion and dilution occurs along the 1.6-mi reach immediately upstream from the MDNR sampling site. Measurements of fecal bacteria decay in Shoal Creek during July 2001 indicated that about 8 percent of fecal coliform and E. coli bacteria decay each hour with an average first-order decay constant of 0.084 h-1 (per hour). Results of field test plots indicated that substantial numbers of fecal bacteria present in poul try litter can survive in fields for as much as 8 weeks after the application of the litter to the land surface. Median densities of fecal coliform and E. coli in slurry-water samples collected from fields increased from less than 60 col/100 mL before the application of turkey and broiler litter, to as large as 420,000 and 290,000 col/100 mL after the application of litter. Bacteria densities in the test plots generally decreased in a exponential manner over time with decay rates ranging from 0.085 to 0.185 d-1 (per day) for fecal coliform to between 0.100 and 0.250 d-1 for E. coli. The apparent survival of significant numbers of fecal bacteria on fields where poultry litter has been applied indicates that runoff from these fields is a potential source of fecal bacteria to vicinity streams for many weeks following litter application.

  6. Analysis of borehole-radar reflection logs from selected HC boreholes at the Project Shoal area, Churchill County, Nevada

    USGS Publications Warehouse

    Lane, J.W., Jr.; Joesten, P.K.; Pohll, G.M.; Mihevic, Todd

    2001-01-01

    Single-hole borehole-radar reflection logs were collected and interpreted in support of a study to characterize ground-water flow and transport at the Project Shoal Area (PSA) in Churchill County, Nevada. Radar logging was conducted in six boreholes using 60-MHz omni-directional electric-dipole antennas and a 60-MHz magnetic-dipole directional receiving antenna.Radar data from five boreholes were interpreted to identify the location, orientation, estimated length, and spatial continuity of planar reflectors present in the logs. The overall quality of the radar data is marginal and ranges from very poor to good. Twenty-seven reflectors were interpreted from the directional radar reflection logs. Although the range of orientation interpreted for the reflectors is large, a significant number of reflectors strike northeast-southwest and east-west to slightly northwest-southeast. Reflectors are moderate to steeply dipping and reflector length ranged from less than 7 m to more than 133 m.Qualitative scores were assigned to each reflector to provide a sense of the spatial continuity of the reflector and the characteristics of the field data relative to an ideal planar reflector (orientation score). The overall orientation scores are low, which reflects the general data quality, but also indicates that the properties of most reflectors depart from the ideal planar case. The low scores are consistent with reflections from fracture zones that contain numerous, closely spaced, sub-parallel fractures.Interpretation of borehole-radar direct-wave velocity and amplitude logs identified several characteristics of the logged boreholes: (1) low-velocity zones correlate with decreased direct-wave amplitude, indicating the presence of fracture zones; (2) direct-wave amplitude increases with depth in three of the boreholes, suggesting an increase in electrical resistivity with depth resulting from changes in mineral assemblage or from a decrease in the specific conductance of ground water; and (3) an increase in primary or secondary porosity and an associated change in mineral assemblage, or decrease in ground water specific conductance, was characterized in two of the boreholes below 300 m.The results of the radar reflection logging indicate that even where data quality is marginal, borehole-radar reflection logging can provide useful information for ground-water characterization studies in fractured rock and insights into the nature and extent of fractures and fracture zones in and near boreholes.

  7. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska

    PubMed Central

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles. PMID:18521716

  8. Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2009-05-01

    There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles. PMID:18521716

  9. Modeling Catastrophic Barrier Island Dynamics

    NASA Astrophysics Data System (ADS)

    Whitley, J. W.; McNamara, D.

    2012-12-01

    Barrier islands, thin strips of sand lying parallel to the mainland coastline, along the U.S. Atlantic and Gulf Coasts appear to have maintained their form for thousands of years in the face of rising sea level. The mechanisms that allow barrier islands to remain robust are transport of sediment from the ocean side of barriers to the top and backside during storms, termed island overwash, and the growth and alongshore propagation of tidal deltas near barrier island inlets. Dynamically these processes provide the necessary feedbacks to maintain a barrier island in an attractor that withstands rising sea level within a phase space of barrier island geometrical characteristics. Current barrier island configurations along the Atlantic and Gulf coasts exist among a wide range of storm climate and underlying geologic conditions and therefore the environment that forces overwash and tidal delta dynamics varies considerably. It has been suggested that barrier islands in certain locations such as those between Avon and Buxton (losing 76% of island width since 1852) and Chandeleur islands (losing 85% of its surface area since 2005) along the Atlantic and Gulf coasts, respectively, may be subject to a catastrophic shift in barrier island attractor states - more numerous inlets cutting barriers in some locations and the complete disappearance of barrier islands in other locations. In contrast to common models for barrier islands that neglect storm dynamics and often only consider cross-shore response, we use an alongshore extended model for barrier island dynamics including beach erosion, island overwash and inlet cutting during storms, and beach accretion, tidal delta growth and dune and vegetation growth between storms to explore the response of barrier islands to a wide range of environmental forcing. Results will be presented that show how barrier island attractor states are altered with variations in the rate of sea level rise, storminess, and underlying geology. We will also investigate the conditions necessary for a barrier island attractor similar to those found along the Atlantic and Gulf coasts to become unstable.

  10. Control technology assessment for coal gasification and liquefaction processes, Tennessee Valley Authority, National Fertilizer Development Center, ammonia plant, Muscle Shoals, Alabama. Report for the site visit of September 1981. Final report

    Microsoft Academic Search

    Telesca

    1982-01-01

    A control technology survey was conducted at the ammonia synthesis facility operated by the Tennessee Valley Authority, National Fertilizer Development Center (SIC-2874), in Muscle Shoals, Alabama on September 1 and 2, 1981. The visit was made to identify processes or hazards similar to those found in coal conversion operations and to report control technologies that might be applicable to both

  11. Maternal condition, yolk androgens and offspring performance: a supplemental feeding experiment in the lesser black-backed gull (Larus fuscus).

    PubMed Central

    Verboven, Nanette; Monaghan, Pat; Evans, Darren M; Schwabl, Hubert; Evans, Neil; Whitelaw, Christine; Nager, Ruedi G

    2003-01-01

    It has been proposed that the maternal androgens in avian egg yolk enhance offspring fitness by accelerating growth and improving competitive ability. Because egg quality is strongly influenced by maternal condition, we predicted that females in good condition would produce high-quality eggs with relatively high androgen content. We experimentally enhanced maternal condition by supplementary feeding lesser black-backed gulls (Larus fuscus) during egg formation and compared the concentrations of androstenedione (A4), 5alpha-dihydrotestosterone (DHT) and testosterone (T) in their eggs with those in eggs laid by control females. We also measured circulating levels of T in females immediately after laying. Egg androgens could affect offspring performance directly through chick development and/or indirectly through changes in the competitive ability of a chick relative to its siblings. To avoid confounding these two routes, and to separate effects operating through the egg itself with those operating through experimental changes in parental chick rearing capacity, we fostered eggs from both maternal treatment groups singly into the nests of unmanipulated parents. Contrary to expectation, mothers with experimentally enhanced body condition laid eggs with lower levels of androgens, while exhibiting higher circulating T concentrations post-laying. Despite these lower levels of egg androgen, offspring hatched from eggs laid by mothers in good condition did not show reduced growth or survival when reared in the absence of sibling competition. Our results demonstrate that yolk androgen concentrations vary with the body condition of the female at the time of egg formation and that females in good condition reduced the yolk androgen content of their eggs without altering offspring performance. PMID:14613608

  12. HEAT ISLAND REDUCTION STRATEGIES GUIDEBOOK

    EPA Science Inventory

    This heat island reduction strategies guidebook provides an overview of urban heat islands and steps communities can take to reduce them. In particular, this guidebook provides background basics and answers the questions: ?What is a heat island?? ?What are its impacts?" "What ar...

  13. Density compensation in island avifaunas

    Microsoft Academic Search

    S. Joseph Wright

    1980-01-01

    This paper analyzes factors which determine the extent of density compensation on islands; i.e., is the summed population density of all species on an island equal to the summed mainland density? A graphical analysis allows quantitative comparisons of density compensation studies. Two hypotheses which are generally applicable predict the extent of density compensation on islands: (1) Niche theory predicts that

  14. Three Mile Island

    Microsoft Academic Search

    M. S. Wood; S. M. Shultz

    1988-01-01

    This bibliography is divided into the following categories: Accident Overviews, Sequence and Causes; International Commentary and Reaction; Emergency Preparedness and Disaster Planning; Health Effects; Radioactive Releases and the Environment; Accident Investigations\\/Commissions; Nuclear Industry: Safety, Occupational, and Financial Issues; Media and Communications; Cleanup; Sociopolitical Response and Commentary; Restart; Legal Ramifications; Federal Documents: President's Commission on the Accident at Three Mile Island;

  15. Three Mile Island revisited

    Microsoft Academic Search

    B. L. Lipford; N. M. Cole; T. J. Friderichs

    1991-01-01

    As a result of the accident in March 1979, the Three Mile Island Unit 2 (TMI-2) reactor vessel sustained significant internal damage. Approximately half of the reactor core suffered some degree of melting, with 10 to 20 tons of molten core material relocating inside the vessel and flowing down onto the reactor vessel's lower head. The resulting damage and the

  16. URBAN EXTENTS Falkland Islands

    E-print Network

    Columbia University

    URBAN EXTENTS BRAZIL CHILE PARAGUAY URUGUAY GRUMPv1 Falkland Islands A t l a n t i c O c e a n P Tropical (CIAT). Global Rural-Urban Mapping Project (GRUMP), Population Density. Palisades, NY: CIESIN Equal Area Projection Urban Extent Administrative Units National Boundaries Note: National boundaries

  17. Atsena Otie Key Island

    USGS Multimedia Gallery

    Atsena Otie Key is one of thirteen islands on Florida's Gulf Coast that make up Cedar Keys National Wildlife Refuge. Nearby waters support a multi-million dollar clam-farming industry. USGS documented pre-oil coastal conditions near the Refuge with baseline petrochemical measurements and aerial phot...

  18. Japan: Shikoku Island

    Atmospheric Science Data Center

    2013-04-16

    ... energy balance, and directly sampled airborne dust and pollution particles while the Multi-angle Imaging SpectroRadiometer (MISR) and ... for Atmospheric Research (NCAR) C-130 aircraft probed the environment near Oki island, in the upper left part of the images. At the same ...

  19. Siberian Expedition: Wrangel Island

    NSDL National Science Digital Library

    This web site chronicles an American Museum of Natural History research expedition in 1998 to Siberia's Wrangel Island to collect woolly mammoth bones and test the theory that lethal disease caused the mammal's extinction. Information on the team members and journal excerpts are included as well as information on the expedition's objectives and the important tools used by the team.

  20. Kiritimati, Kiribati (Christmas Island)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Pronounced 'Ki-ris-mas,' Kiritimati Island has a large infilled lagoon that gives it the largest land area (125 square miles, 321 square km) of any atoll in the world. Captain Cook named the atoll Christmas Island when he arrived on Christmas Eve in 1777. Used for nuclear testing in the 1950s and 1960s, the island is now valued for its marine and wildlife resources. It is particularly important as a seabird nesting site-with an estimated 6 million birds using or breeding on the island, including several million Sooty Terns. Rainfall on Kiritimati is linked to El Nino patterns, with long droughts experienced between the wetter El Nino years. This image is based on a mosaic of four digital photographs taken on 16 January 2002 from the Space Station Alpha as part of the Crew Earth Observations Project. The underlying data have 10 meter spatial resolution. Coral reefs are one of the areas selected as a scientific theme for this project (see also the recent Earth Observatory article, Mapping the Decline of Coral Reefs. The mosaic, based on images ISS004-ESC-6249 to 6252, was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.