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1

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

NASA Astrophysics Data System (ADS)

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 new geological field survey was carried out at scale 1:10000 and locally at 1:2000, establishing informal stratigraphic units that on the whole fit a common scheme of evolution for volcanic ocean islands. In this framework, the whole pre-existing stratigraphy has been revised. Ustica has a variety of volcanic deposits from submarine (basaltic effusive to explosive) to subaereal (effusive, explosive and highly explosive -Plinian?). Moreover, Ustica is one of the few places in the world where a transition of deposits from shoaling to emergent stage crop out. In fact, its oldest deposits consist of: (a) a flank-facies association of submarine lavas (variably-shaped pillows, pillow breccias and hyaloclastites) with biocalcarenite-biocalcirudite lenses, dipping coastward in the E, S and W outer parts of the island; this association is arranged in steep foreset beds (lava deltas) and is capped by flat-lying transitional to subaereal massive lava flows and surf-shaped boulder conglomerates; the geometry of this association may suggest a progressive island uplift or sea lowering during this period; (b) shallow-water to emergent tuff cone deposits in the NW part of the island. In the centre of the island, subsequent activity built a pile, now deeply eroded, of subaereal basaltic lava flows capped by a scoria cone. A previously unknown outcrop where a pumice fall layer is exposed, allows a distinction into two members of a unit that was known as formed by pyroclastic surges only. Higher in the succession, the Ustica Pumice formation (for which 4 members are defined) is underlain by a palaeosoil, and is likely the remnant of a caldera-forming eruption, which possibly dismantled the northern part of the island. It may be suggested that a later flank collapse affected the W side of the island, exposing seamount-stage deposits and allowing small fissural eruptions. The northern part of the island was then rebuilt by hydro-magmatic littoral deposits, subaereal aa flows, and thick columnar lava flows. At the NE corner of the island, a littoral tuff cone (the only cone of the island which is roughly preserved in its original shape) gave the last volcanic activity in Ustica. Acknowledgement: LBM benefited of a grant from Milan University under the supervision of Prof. G.Pasquaré in the framework of a joint venture with SGN.

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

2003-04-01

2

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

PubMed

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

Roca, V; Lafuente, M; Carbonell, E

1999-10-01

3

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

USGS Publications Warehouse

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).

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

2011-01-01

4

Factors affecting marine debris deposition at French Frigate Shoals, Northwestern Hawaiian Islands Marine National Monument, 1990–2006  

Microsoft Academic Search

Data on the amount and type of small debris items deposited on the beaches of the Hawaiian Islands National Wildlife Refuge Tern Island station, French Frigate Shoals were collected over 16 years. We calculated deposition rates and investigated the relationship among deposition and year, season, El Niño and La Niña events from 1990 to 2006. In total 52,442 debris items

Carey Morishige; Mary J. Donohue; Elizabeth Flint; Christopher Swenson; Christine Woolaway

2007-01-01

5

Heavy metal and selenium levels in feathers of herring gulls ( Larus argentatus ): Differences due to year, gender, and age at Captree, Long Island  

Microsoft Academic Search

The concentrations of heavy metals (mercury, lead, cadmium, chromium, manganese) and selenium in the feathers of herring gulls (Larus argentatus) from a nesting colony at Captree, Long Island, New York were examined from 1989 to 1993 to determine if there were differences from year to year, and between males and females, adult and young, and dead versus live gulls. Variation

Joanna Burger

1995-01-01

6

Factors affecting marine debris deposition at French Frigate Shoals, Northwestern Hawaiian Islands Marine National Monument, 1990-2006.  

PubMed

Data on the amount and type of small debris items deposited on the beaches of the Hawaiian Islands National Wildlife Refuge Tern Island station, French Frigate Shoals were collected over 16 years. We calculated deposition rates and investigated the relationship among deposition and year, season, El Niño and La Niña events from 1990 to 2006. In total 52,442 debris items were collected with plastic comprising 71% of all items collected. Annual debris deposition varied significantly (range 1116-5195 items) but was not influenced by season. Debris deposition was significantly greater during El Niño events as compared to La Niña events. Although often deduced to influence floating marine pollution, this study provides the first quantitative evidence of the influence of El Niño/La Niña cycles on marine debris deposition. PMID:17572447

Morishige, Carey; Donohue, Mary J; Flint, Elizabeth; Swenson, Christopher; Woolaway, Christine

2007-08-01

7

THE BREEDING SUCCESS OF TWO SYMPATRIC GULLS, THE HERRING GULL AND THE GREAT BLACK-BACKED GULL  

Microsoft Academic Search

ARIOUS aspects of the breeding biology of the Herring Gull (Larus argentatus) and the Great Black-backed Gull (Lams marinus) were examined on Sandy Point, a small coastal island near Westerly, Rhode Island. Since no extensive studies have been made on interactions between gull species, the project provided an ideal opportunity to examine several param- eters of breeding in the two

R. MICHAEL ERWIN

8

PARENTAL INDEMNIFICATION FORM FOR ALL MINORS IN USER PROGRAMS at the Shoals Marine Laboratory on Appledore Island, Maine.  

E-print Network

PARENTAL INDEMNIFICATION FORM FOR ALL MINORS IN USER PROGRAMS at the Shoals Marine Laboratory in the future against Shoals Marine Lab on account of personal injury, property damage, death or accident of any. Print participant name Parent/Guardian signature (date) Parent/Guardian name #12;

9

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.

10

Variability of mercury and selenium levels in clutches of Audouin's gulls (Larus audouinii) breeding at the Chafarinas Islands, Southwest Mediterranean.  

PubMed

We determined mercury and selenium in 43 eggs (eggshell, albumen, and yolk) which belong to different clutch sizes of Audouin's gull from the Chafarinas Islands. The results were compared with those obtained previously with the same species at the Ebro Delta. Both, the intra- and the interclutch sources of variability have been examined. There is an effect of the female on mercury and selenium concentrations in a clutch, which supports the use of eggs as monitoring tools. The distribution pattern of mercury among albumen, yolk and eggshell, the dynamics of this element during the laying process, as well as data concerning egg formation strategies suggest that the mercury in the albumen corresponds mainly to the mercury acquired by the female while feeding in the breeding area. The mercury and selenium levels of the eggs from the Chafarinas Islands were lower than those of the Ebro Delta, which can be due to differences in both the marine contamination and the diet in the two colonies. PMID:10790510

Sanpera, C; Morera, M; Ruiz, X; Jover, L

2000-07-01

11

Can rats prey on gull eggs? An experimental approach  

Microsoft Academic Search

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

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

2003-01-01

12

ARCTIC Sabine’s Gull (Xema sabini), Ross’s Gull (Rhodostethia rosea) and Ivory Gull (Pagophila  

E-print Network

ABSTRACT. 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 breeding places of Ross’s gull in northeastern Siberia. Recently new breeding places have been reported from U.S.S.R. (Taymyr Peninsula, 1973), Canada (near Devon Island, 1976 and 1978; near Churchill, Manitoba, 1980) and Greenland (Peary Land and Disko Bay, 1979). Sabine’s gull and Ivory gull have a dispersed and patchy distribution with gaps too wide for them to be regarded as true continuous circumpolar species. The biotope requirements for the three species are compared. All three are food opportunists; recent data on their food choice and foraging behaviour are reviewed and discussed. The breeding ecology of the gulls is updated with special attention to the clutch size, where a climatological trend may be distinguished. In contrast to birds in general, the most southerly breeding species (Ross’s gull) has the largest clutch size and the most northerly breeding species (Ivory gull) has the smallest. Details of the large interspecific differences in migratory and wintering habits are presented. The documented northbound autumn migration of Ross’s gull observed in Alaska and the southbound migration of Sabine’s gull to western South America and southwestern and southern Africaare surveyed. The Ivory gull is regarded as a straggler during the winter, but recent observations on East Greenland of at least 500 migrating birds in September 1975 indicate that specific migratory routes may be used by this species too. RkSUMk. Les toutes premibres informations concernant la mouette de Sabine, la mouette rose et le goeland senateur, furent

Sven Blomqvist; Magnus Elander

13

Activity periods and questing behavior of the seabird tick Ixodes uriae (Acari: Ixodidae) on Gull Island, Newfoundland: the role of puffin chicks.  

PubMed

Questing behavior of Ixodes uriae and their associated seasonal, host-feeding patterns are crucial to our understanding of tick life history strategies and the ecology of diseases that they transmit. Consequently, we quantified questing behavior of nymphs and adult female I. uriae ticks at Gull Island, a seabird colony in Newfoundland, Canada, to examine seasonal variation of off-host and on-host tick activity. We sampled a total of 133 adult Atlantic puffins (Fratercula arctica), 152 puffin chicks, and 145 herring gull (Larus argentatus) chicks for ticks during the breeding seasons of 2004 and 2005. Questing ticks were sampled by dragging a white flannel cloth across the grassy breeding areas during the mo of May, June, July, and August. Nymph questing activity reached a peak during mid-July (79 and 110 individuals/hr in 2004 and 2005, respectively). The prevalence of nymphs and adult female ticks on different seabird hosts varied between years and during the seasons. Puffin chicks had the highest prevalence (above 70% in July) of nymphs in both years and this was correlated with questing activity. Female ticks rarely fed on puffin chicks, but were prevalent on adult puffins and gulls, although prevalence and questing of ticks were not correlated in these hosts. These patterns of off-host and on-host tick activity suggests that I. uriae ticks likely use a combination of questing and passive waiting, e.g., in puffin burrows, to detect hosts, depending on the tick stage and the host species. PMID:17539407

Muzaffar, Sabir B; Jones, Ian L

2007-04-01

14

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

15

Gull eggs--food of high organic pollutant content?  

PubMed

A wide range and occasionally high levels of persistent organic pollutants (POPs) are reported in Arctic regions, especially among top predators. Polar bears (Ursus maritimus), arctic foxes (Alopex lagopus) and some gull species (Larus spp.) often have high levels of these fat-soluble pollutants. Gulls deposit significant levels of these contaminants in their eggs. In northern regions, gull eggs are part of the traditional human diet. In the present study we have investigated the levels of POPs in gull eggs in order to determine the tolerable weekly intake (TWI) for humans. Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in 214 gull eggs collected in the spring of 2001-02. The eggs were collected from four gull species (herring gulls (Larus argentatus), great black-backed gulls (L. marinus), lesser black-backed gulls (L. fuscus) and glaucous gulls (L. hyperboreus)) at 12 different locations in Northern Norway, on the Faroe Islands and on Svalbard. The pollutant levels in gull eggs were found to be 65.5 +/- 26.9 pg toxic equivalent (TE) for dioxin and PCB g(-1) wet weight. Based on these findings and the TWI-value determined by the EU Scientific Committee on Food it is advised that children, young women and pregnant and nursing women should not eat gull eggs. Other people should limit their intake of eggs to an absolute minimum, considering the health risks associated with gull egg intake. PMID:15931427

Pusch, Kerstin; Schlabach, Martin; Prinzinger, Roland; Wing Gabrielsen, Geir

2005-06-01

16

Heavy Metals and Selenium in Herring Gulls (LARUS ARGENTATUS) NESTING IN COLONIES FROM EASTERN LONG ISLAND TO VIRGINIA  

Microsoft Academic Search

With increasing interest in assessing the health or well-being ofcommunities and ecosystems, birds are being used asbioindicators. Coloniallynesting species breed mainly in coastal areas that are alsopreferred for humandevelopment, exposing the birds to various pollutants. Inthis paper concentrations of heavy metal and selenium in the feathers ofHerring Gulls(Larus argentatus) nesting in several colonies fromMassachusetts toDelaware are reported. There were significant

Joanna Burger

1997-01-01

17

Aerial estimation of the size of gull breeding colonies  

USGS Publications Warehouse

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.

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

1968-01-01

18

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

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

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

1992-01-01

19

MITE (ACARINA) POPULATIONS IN RING-BILLED GULL NESTS  

Microsoft Academic Search

Can. Ent. 106: 319-327 (1974) Mites collected from 69 Larus delawarensis Ord nests on Granite Island, Lake Superior, northwestern Ontario, during the summers of 1972 and 1973 showed phenological relationships with the breeding cycle of the gulls. The populations of five selected mite genera varied in relation to nest initiation, egg laying, and egg hatching periods of the gulls. Moisture

R. Freitag; J. P. Ryder; P. Wanson

1974-01-01

20

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

Microsoft Academic Search

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

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

2003-01-01

21

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

Microsoft Academic Search

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

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

2006-01-01

22

Retraction of a longevity record for a 36-year-old herring gull  

USGS Publications Warehouse

Full text: The longevity record for a 36-year-old Herring Gull, Larus argentatus (Pettingill 1967, Auk 84: 123), is erroneous. Herring Gull with band number A-676871, the basis of the record, was found dead on 20 June 1966 on the shore of Little Traverse Bay near Petoskey, Michigan, and reported to the Bird Banding Laboratory. The laboratory then mistakenly advised Pettingill that this gull was banded by him on 29 June 1930 on coastal Maine. He actually banded Herring Gull number A-676871 as a young bird on one of the Beaver Islands in Lake Michigan on 8 July 1948. The gull was thus 18 instead of 36 years old.

Jonkel, G.M.; Pettingill, O.S., Jr.

1974-01-01

23

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

PubMed

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

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

2014-02-01

24

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

USGS Publications Warehouse

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.

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

1995-01-01

25

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

PubMed

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

Franson, J C; Pearson, J E

1995-07-01

26

EFFECTS OF NINE YEARS OF FOX PREDATION ON TWO SPECIES OF BREEDING GULLS  

Microsoft Academic Search

ABSTR^CT.--Ring-billed Gulls (Larus delawarensis) and Herring Gulls (L. argentatus) nesting on South Manitou Island in Lake Michigan were subjected to at least 9 yr of intense fox predation. Both gull species experienced total or nearly total reproductive failure during all but 1 yr between 1975 and 1983. The number of active nests declined significantly during this period, with Ring-bills showing

STEPHEN R. PATTON; LISE A. HANNERS

27

Late Holocene chronology, origin, and evolution of the St. Bernard Shoals, Northern Gulf of Mexico, USA  

NASA Astrophysics Data System (ADS)

Several shore-parallel marine sand bodies lie on the Louisiana continental shelf. They are Trinity Shoal, Ship Shoal, Outer Shoal, and the St. Bernard Shoals. These shoals mark the submerged positions of ancient shorelines associated with abandoned deltas. Three of these shoals are single elongate deposits. The fourth shoal, the St. Bernard Shoals, consists of a group of discrete sand bodies ranging in size from 44 to 0.05 km2, 25 km southeast of the Chandeleur Islands in 15-18 m of water. The St. Bernard Shoals are stratigraphically above the St. Bernard delta complex, which was active 2,500-1,800 years b. p. Understanding the evolution of the St. Bernard Shoals is necessary to reconstruct the Holocene chronology of the St. Bernard delta complex and the eastern Louisiana continental shelf. For this study, 47 vibracores and 400 km of shallow seismic reflection data collected in 1987 across the Louisiana shelf were analyzed. In June 2008, 384 km of higher-resolution seismic reflection data were acquired across the study area and appended to the preexisting datasets. Vibracores were integrated with seismic profiles to identify facies and their regional distribution. Our results demonstrate that the deltaic package stratigraphically below the St. Bernard Shoals is chronologically younger than the northern distributaries, but derived from the same trunk distributary channel (Bayou la Loutre). The river eventually bypassed the northern distributaries, and began to deposit sediment further onto the continental shelf. After abandonment, the overextended delta lobe was rapidly transgressed, creating a transgressive shoreline that eventually coalesced with earlier shorelines in the region to form the Chandeleur Islands. The St. Bernard Shoals formed by the reworking of the relict distributary deposits exposed on the inner to mid shelf during and subsequent to shoreface ravinement.

Rogers, Bryan E.; Kulp, Mark A.; Miner, Michael D.

2009-12-01

28

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

Microsoft Academic Search

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.

Rimantas R. Budrys; Remigijus Gegelevi?ius

2002-01-01

29

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

PubMed

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

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

2003-01-01

30

Shoal, Nevada Site Fact Sheet  

SciTech Connect

The Shoal Site is situated on 2,560 acres of withdrawn federal lands located within the north-central portion of the Sand Springs Range in Churchill County, Nevada. The town of Fallon is the largest populated area in the region and is about 30 miles northwest of the site. The region around the Shoal Site is sparsely populated; military installations, recreation, ranching, and mining provide the dominant commercial interests. The Project Shoal underground nuclear test was part of the Vela Uniform program sponsored jointly by the U.S Department of Defense and U.S. Atomic Energy Commission (AEC), a predecessor agency of the U.S. Department of Energy (DOE). Vela Uniform was a research and development program directed toward locating, detecting, and identifying underground detonations. The objective of Project Shoal was to detonate a nuclear device underground in an active seismic area to improve the United States' ability to detect, identify, and locate underground nuclear detonations.

None

2009-04-01

31

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

USGS Publications Warehouse

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.

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

2014-01-01

32

Fish shoal composition: mechanisms and constraints.  

PubMed

Observations were made on three fish species (banded killifish (Fundulus diaphanus), golden shiner (Notemigonus crysoleucas) and white sucker (Catostomus commersoni)) in a temperate lake (New Brunswick, Canada) in order to investigate the relationship between shoal choice behaviour of individual fishes and shoal composition. Encounters between shoals were observed to take place every 1.1 min per shoal and an encounter lasted 3.7 s on average. The duration of shoal encounters was influenced by shoal size but not by differences between shoals in either body length or species. Conversely, the outcome of shoal encounters (i.e. ences between shoals in either body length or species. Conversely, the outcome of shoal encounters (i.e. whether or not an individual changes shoal) was influenced by body length and species differences but not by shoal size. Together, these results suggest that encounter duration itself is unlikely to have an important influence on encounter outcome. The collection of ten entire fish shoals showed that they were assorted by species and body length. A simulation model demonstrated that individual shoal choice behaviour alone could account for the generation and maintenance of the observed levels of size assortedness of shoals without invoking the existence of other sorting mechanisms such as differential swimming speeds. However, the generation of species assortedness was not predicted by the model. Furthermore, our data suggest that fish density acts as a constraint on shoal choice, influencing both shoal size and composition. This work has implications for studies on information transfer and reciprocal altruism within populations. PMID:11075715

Krause, J; Hoare, D J; Croft, D; Lawrence, J; Ward, A; Ruxton, G D; Godin, J G; James, R

2000-10-01

33

Fish shoal composition: mechanisms and constraints.  

PubMed Central

Observations were made on three fish species (banded killifish (Fundulus diaphanus), golden shiner (Notemigonus crysoleucas) and white sucker (Catostomus commersoni)) in a temperate lake (New Brunswick, Canada) in order to investigate the relationship between shoal choice behaviour of individual fishes and shoal composition. Encounters between shoals were observed to take place every 1.1 min per shoal and an encounter lasted 3.7 s on average. The duration of shoal encounters was influenced by shoal size but not by differences between shoals in either body length or species. Conversely, the outcome of shoal encounters (i.e. ences between shoals in either body length or species. Conversely, the outcome of shoal encounters (i.e. whether or not an individual changes shoal) was influenced by body length and species differences but not by shoal size. Together, these results suggest that encounter duration itself is unlikely to have an important influence on encounter outcome. The collection of ten entire fish shoals showed that they were assorted by species and body length. A simulation model demonstrated that individual shoal choice behaviour alone could account for the generation and maintenance of the observed levels of size assortedness of shoals without invoking the existence of other sorting mechanisms such as differential swimming speeds. However, the generation of species assortedness was not predicted by the model. Furthermore, our data suggest that fish density acts as a constraint on shoal choice, influencing both shoal size and composition. This work has implications for studies on information transfer and reciprocal altruism within populations. PMID:11075715

Krause, J; Hoare, D J; Croft, D; Lawrence, J; Ward, A; Ruxton, G D; Godin, J G; James, R

2000-01-01

34

Mercury trends in herring gull (Larus argentatus) eggs from Atlantic Canada, 1972-2008: Temporal change or dietary shift?  

PubMed

Mercury (Hg) is a pervasive contaminant that can adversely affect predatory wildlife. Bird eggs provide insights into breeding females' Hg burdens, and are easily collected and archived. We present data on Hg trends in herring gull (Larus argentatus) eggs from five sites in Atlantic Canada from 1972 to 2008. We found a significant decrease in Hg at Manawagonish Island, New Brunswick and Île du Corossol, Quebec, but after correcting Hg for dietary shifts using stable isotopes (?(15)N), these trends disappeared. Decreasing temporal trends of stable isotopes in gull eggs were observed at four sites, suggesting shifts in gull diets. At Gull Island, Newfoundland, diet-adjusted Hg increased from 1977 to 1992, dropped sharply between 1992 and 1996, and rose again from 1996 to 2008. After adjusting Hg trends for dietary shifts of herring gulls, it appears that environmental Hg in coastal ecosystems has remained relatively constant at most sites in Atlantic Canada over the last 36 years. PMID:23063997

Burgess, Neil M; Bond, Alexander L; Hebert, Craig E; Neugebauer, Ewa; Champoux, Louise

2013-01-01

35

Heavy metal concentrations in Black-tailed Gull (Larus crassirostris) chicks, Korea.  

PubMed

The objectives of this study were to quantify concentrations of heavy metals in livers and stomach contents of Black-tailed Gull (Larus crassirostris) chicks from two islands in Korea. Iron and manganese concentrations were significantly higher in chick livers at Hongdo Island compared to Rando Islnad. In contrast, zinc, copper and cadmium concentrations were significantly higher at Rando Island than Hongdo Island. On Hongdo Island, Black-tailed Gull chicks at a lighthouse site had higher lead concentrations in livers and stomach contents than at a nearby reference site and stomach contents of Black-tailed Gull chicks had significantly higher lead concentrations than regurgitated diets. In Hongdo Island, manganese, lead and cadmium concentrations were significantly correlated between livers and stomach contents. Essential elements such as iron, zinc, manganese and copper concentrations from the present study were within the range reported for other seabird species including gulls. Livers of four individual gull chicks (13.3%) were at a level considered lead exposed (6-30 ?g g(-1) dry weight), but cadmium concentrations in all specimens were within the background level (<3 ?g g(-1) dry weight) for wild birds. Elevated lead concentrations on lighthouse site may be attributed to ingestion of paint chips and these concentrations may negatively affect chick behavior, growth and survival. PMID:25048929

Kim, Jungsoo; Oh, Jon-Min

2014-10-01

36

Journal of Coastal Research SI 59 256-265 West Palm Beach, Florida 2011 Channel Shoaling with Deepening of Houma Navigation Channel at  

E-print Network

Journal of Coastal Research SI 59 256-265 West Palm Beach, Florida 2011 Channel Shoaling-265. West Palm Beach (Florida), ISSN 0749-0208. This study evaluated the potential increase in shoaling be placed on the bayside of the island and sand similar to or coarser than the existing beach sand should

US Army Corps of Engineers

37

Feeding Ecology and the Concentration of Organochlorines in Glaucous Gulls  

Microsoft Academic Search

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

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

2000-01-01

38

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

Microsoft Academic Search

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,

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

2000-01-01

39

Cross-species familiarity in shoaling fishes.  

PubMed Central

Preferential association with familiar shoal mates confers a number of potentially important benefits to individuals, including improved anti-predator effects and the reduction of aggression in competitive interactions. Until now, however, familiarity has been demonstrated purely between conspecifics. Here, we present evidence that familiarity preferences can override natural preferences for conspecifics. Individual focal fishes (chub, Leuciscus cephalus) were given a choice of two stimulus shoals of the same size composed of conspecifics or of heterospecifics (minnows, Phoxinus phoxinus) in a flow tank. A series of four treatments was carried out to investigate the effects of familiarity, induced by a 15 day association between the focal fish and the stimulus fishes, on the choices made by the focal fish. Focal fishes showed a significant preference for conspecifics over heterospecifics when both stimulus shoals were composed of non-familiar individuals. Focal fishes also showed a significant preference for stimulus shoals composed of familiar fishes over stimulus shoals composed of non-familiar fishes when both shoals were conspecific and when both shoals were heterospecific. Finally, the preference of focal fishes for conspecifics disappeared when the alternative, a shoal of heterospecifics, was composed of familiar individuals. The importance of this work is discussed in the context of species interactions in free-ranging shoals. PMID:12816654

Ward, A J W; Axford, S; Krause, J

2003-01-01

40

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...

41

The Effects of Diurnal and Tidal Periodicities in the Numbers and Activities of Herring Gulls Larus argentatus in a Colony  

Microsoft Academic Search

The average numbers of Herring Gulls Larus argentatus present in a breeding colony on Walney Island, Cumbria, were found to vary with the tidal cycle but to remain effectively constant with time of day through the breeding season.\\u000aAn activity survey, based on 50 Herring Gulls observed at half-hourly intervals during March and April 1973, showed that sleep and rest

Joseph G. Galusha; Charles J. Amlaner

1978-01-01

42

Annual Movement Patterns of Endangered Ivory Gulls: The Importance of Sea Ice  

PubMed Central

The ivory gull (Pagophila eburnea) is an endangered seabird that spends its entire year in the Arctic environment. In the past three decades, threats from various sources have contributed to a >70% decline in Canada. To assess the annual habitat needs of this species, we attached satellite transmitters to 12 ivory gulls on Seymour Island, Nunavut in 2010, which provided up to four breeding seasons of tracking data. Analysis of migratory behaviour revealed considerable individual variation of post-breeding migratory route selection. Ivory gulls traveled a median of 74 days during post-breeding migration, but only 18 days during pre-breeding migration. In contrast to predictions, ivory gulls did not use the Greenland coast during migratory periods. Ivory gulls overwintered near the ice edge in Davis Strait, but also used the Labrador Sea in late February and March. We suggest that the timing of formation and recession and extent of sea ice plays a large role in ivory gull distribution and migratory timing. PMID:25551556

Spencer, Nora C.; Gilchrist, H. Grant; Mallory, Mark L.

2014-01-01

43

Annual movement patterns of endangered ivory gulls: the importance of sea ice.  

PubMed

The ivory gull (Pagophila eburnea) is an endangered seabird that spends its entire year in the Arctic environment. In the past three decades, threats from various sources have contributed to a >70% decline in Canada. To assess the annual habitat needs of this species, we attached satellite transmitters to 12 ivory gulls on Seymour Island, Nunavut in 2010, which provided up to four breeding seasons of tracking data. Analysis of migratory behaviour revealed considerable individual variation of post-breeding migratory route selection. Ivory gulls traveled a median of 74 days during post-breeding migration, but only 18 days during pre-breeding migration. In contrast to predictions, ivory gulls did not use the Greenland coast during migratory periods. Ivory gulls overwintered near the ice edge in Davis Strait, but also used the Labrador Sea in late February and March. We suggest that the timing of formation and recession and extent of sea ice plays a large role in ivory gull distribution and migratory timing. PMID:25551556

Spencer, Nora C; Gilchrist, H Grant; Mallory, Mark L

2014-01-01

44

Feeding ecology of long-tailed ducks Clangula hyemalis wintering on the Nantucket Shoals  

USGS Publications Warehouse

A substantial proportion, perhaps 30%, of the North American breeding population of Long-tailed Ducks (Clangula hyemalis) winter in the vicinity of Nantucket Island, Massachusetts. These birds spend the night on Nantucket Sound and commute during daylight hours to the Nantucket Shoals, which extend about 65 km offshore from the southeastern corner of Nantucket. Strip transects done from a single-engine plane in 1997 and 1998 indicated that Long-tailed Ducks foraged over the shallower (<= 20 m depth) portions of the Nantucket Shoals, up to 70 km offshore. Diet analyses of ten birds collected in February 1999 and five in December 2006 showed that they fed principally (106.6 +/- 42.0 individuals per crop) on Gammarus annulatus, a pelagic amphipod that often forms large aggregations, and is consumed by several species of fish and marine mammals. Our findings emphasize the importance of conservation of the Nantucket Shoals and the prevention of oil spills or other potentially harmful accidents.

White, Timothy P.; Veit, Richard R.; Perry, Matthew C.

2009-01-01

45

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

USGS Publications Warehouse

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.

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

1979-01-01

46

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

Microsoft Academic Search

The great black-backed gull (Larus marinus) is widespread in the northern hemisphere, breeding south to Britain and Ireland on the European side of the Atlantic and to Long Island in the United States where populations have increased markedly during the last 50 years. With growing exploitation of oil\\/resources resources, seabird populations are being increasingly threatened by accidental oiling of individuals

Nancy C. Coon; Peter H. Albers; Robert C. Szaro

1979-01-01

47

Breeding biology and relation of pollutants to black skimmers and gull-billed terns in South Carolina  

USGS Publications Warehouse

The breeding biology and relation of pollutants to black skimmers (Ryn chops niger) and gull-billed terns (Gelochelidon nilotica) were investigated in South Carolina from 1969 through 1975. With few exceptions, the two species nested together in colonies located on barrier islands. We located 10 colonies, 7 of which were on the Cape Romain National Wildlife Refuge (Cape Romain); references were located that described nesting on seven other islands in South Carolina that no longer support colonies. Gull-billed terns nested from early May through July; the skimmers started later (late May) but also continued later (early September). Both species nested in areas subject to tidal flooding, and the two species persisted in nesting in several colonies despite intense predation by rats and gulls. Estimated reproductive success varied greatly from year to year and colony to colony; success in most colonies seemed low, particularly for the gull-billed tern. Residues of organochlorine pollutants in several eggs seemed of sufficient magnitude to induce adverse effects on reproductivity and eggshell thickness: however, the overall effect of organochlorines appeared negligible. Maximum numbers of nests located in a single year were 790 for the skimmer and 340 for the gull-billed tern: the total breeding population in South Carolina is unknown. Although nesting islands at Cape Romain and Deveaux Bank are sanctuaries for nesting birds, both species will continue to lose nesting habitat as additional sea islands are developed and inhabited by man.

Blus, Lawrence J.; Stafford, Charles J.

1980-01-01

48

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

USGS Publications Warehouse

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.

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

1999-01-01

49

Current concentrations and spatial and temporal trends in mercury in Great Lakes Herring Gull eggs, 1974-2009.  

PubMed

Current concentrations and spatial and temporal trends of total mercury (Hg) were assessed in eggs of the Herring Gull (Larus argentatus) over the period 1974-2009 at 15 sites in the Great Lakes: 2-3 sites per lake and one site in each of 3 connecting channels. Current (2009) concentrations ranged from 0.064 ?g/g (wet weight) at Chantry Island (Lake Huron) to 0.246 ?g/g at Middle Island (Lake Erie). There were significant inter-colony differences in mean Hg concentrations (2005-2009). Mercury concentrations at 14 of 15 sites declined from 23 to 86% between when it was first measured (usually 1974) and 2009. Declining temporal trends over the entire period (1974-2009) were significant at 10 of the 15 sites. On the other hand, there were no significant trends in mercury over the last 15 years. In the early years, declines of Hg in Herring Gull eggs tracked those in Rainbow Smelt (Osmerus mordax) in most Great Lakes. More recently, declines in gull eggs were more evident than in smelt and may be partially explained by temporal changes in the gull diet. When gull Hg data were adjusted for temporal changes in the gull diet, as inferred from stable nitrogen isotope values in eggs, significant declines in egg mercury levels were found only at 4 of 15 sites. Overall, Hg concentrations have declined in Great Lakes Herring Gull eggs over the period 1974-2009 but changes in the gull diet may be contributing, in part, to those declines. Examination of contaminant temporal trends in multiple indicator species will ensure accurate inferences regarding contaminant availability in the environment. PMID:21833543

Weseloh, D V Chip; Moore, David J; Hebert, Craig E; de Solla, Shane R; Braune, Birgit M; McGoldrick, Daryl J

2011-10-01

50

Alternate reproductive strategies in the California gull  

Microsoft Academic Search

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

B. H. Pugesek; P. Wood

1992-01-01

51

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

PubMed

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

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

2000-01-17

52

Determining shoal membership using affinity propagation.  

PubMed

We propose using the affinity propagation (AP) clustering algorithm for detecting multiple disjoint shoals, and we present an extension of AP, denoted by STAP, that can be applied to shoals that fusion and fission across time. STAP incorporates into AP a soft temporal constraint that takes cluster dynamics into account, encouraging partitions obtained at successive time steps to be consistent with each other. We explore how STAP performs under different settings of its parameters (strength of the temporal constraint, preferences, and distance metric) by applying the algorithm to simulated sequences of collective coordinated motion. We study the validity of STAP by comparing its results to partitioning of the same data obtained from human observers in a controlled experiment. We observe that, under specific circumstances, AP yields partitions that agree quite closely with the ones made by human observers. We conclude that using the STAP algorithm with appropriate parameter settings is an appealing approach for detecting shoal fusion-fission dynamics. PMID:23219963

Quera, Vicenç; Beltran, Francesc S; Givoni, Inmar E; Dolado, Ruth

2013-03-15

53

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

Microsoft Academic Search

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

Lene Østby; Geir Wing Gabrielsen; Åse Krøkje

2005-01-01

54

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

55

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

56

Dynamics of fish shoals: identifying key decision rules  

Microsoft Academic Search

Social aggregations of fish are extremely common in nature. Pitcher (1983) defines a social aggregation of fish as a shoal, with a highly polarized shoal constituting a school. The ultimate causes of fish shoaling have been extensively studied and are well established, with the main causes being protection from predators and enhanced foraging ability. The proximate mechanisms by which groups

Joseph H. Tien; Simon A. Levin; Daniel I. Rubenstein

2004-01-01

57

Created versus natural coastal islands: Atlantic waterbird populations, habitat choices, and management implications  

USGS Publications Warehouse

Nesting colonial waterbirds along the Atlantic Coast of the United States face a number of landscape-level threats including human disturbance, mammalian predator expansion, and habitat alteration. There have been changes from 1977 to the mid-1990s in use of nesting habitats and populations of a number of seabird species of concern in the region, including black skimmers Rynchops niger Linnaeaus, common terns Sterna hirundo Linnaeaus, gull-billed terns Sterna nilotica Linnaeaus, least terns Sterna antillarum Lesson, royal terns Sterna maxima Boddaert, and sandwich terns Sterna sandvicensis Cabot. These species form colonies primarily on the following habitat types: large, sandy barrier or shoal islands, natural estuarine or bay islands (mostly marsh), man-made islands of dredged deposition materials (from navigation channels), and the mainland. Significant changes in the use of the dredged material islands have occurred for these species in New Jersey and North Carolina, but not in Virginia. Population declines and changes in bird habitat use appear to be at least partially associated with the conditions and management of the existing dredged material islands, coastal policy changes associated with creating new dredged material islands, and competing demands for sand for beach augmentation by coastal communities. As these and other coastal habitats become less suitable for colonial waterbirds, other manmade sites, such as bridges and buildings have become increasingly more important. In regions with intense recreational demands, coastal wildlife managers need to take a more aggressive role in managing natural and man-made habitats areas and as stakeholders in the decision-making process involving dredged materials and beach sand allocation.

Erwin, R.M.; Allen, D.H.; Jenkins, D.

2003-01-01

58

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

PubMed

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

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

2004-04-01

59

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

PubMed Central

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

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

2004-01-01

60

Data Decision Analysis: Project Shoal  

SciTech Connect

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.

Forsgren, Frank; Pohll, Greg; Tracy, John

1999-01-01

61

Kin assortment in juvenile shoals in wild guppy populations  

PubMed Central

Grouping provides many potential benefits to individuals in terms of foraging and anti-predator protection. However, it has been suggested that individuals could gain additional benefits in terms of indirect fitness by grouping with kin. Surprisingly, the genetic composition of wild fish shoals and the importance of kin-associated shoaling remain poorly understood. The Trinidadian guppy (Poecilia reticulata) has life history traits that might promote kin structure of shoals such as internal fertilisation and small brood size in contrast to many other fish species. Even though previous studies did not find any indication of kin structure in shoals of adult guppies, it is possible that related juveniles remain together in shoals, partly because of lower mobility and because the advantages of kin association may change with age. Using 10 microsatellite markers, we conducted a genetic analysis on 40 shoals from four populations. Pair-wise relatedness was inferred using a modified version of the software package COLONY and permutation tests were conducted to test the hypothesis that kin occur together in juvenile shoals more often than expected by chance. The frequency of sib dyads among juveniles within shoals was significantly larger than that between shoals in two high predation populations but not in two low predation populations. This finding contributes to the understanding of factors underlying shoal composition and highlights the potential of recent methodological advances for detecting such relationships. PMID:20823907

Piyapong, C; Butlin, R K; Faria, J J; Scruton, K J; Wang, J; Krause, J

2011-01-01

62

Organochlorine poisoning of ring-billed gulls in southern Ontario.  

PubMed

Clinical, necropsy, bacteriologic, parasitologic, histopathologic, toxicologic and animal inoculation studies suggest that organochlorine (PBC, dieldrin and DDE) poisoning was an important factor in causing deaths of free-flying ring-billed gulls (Larus delawarensis) in southern Ontario in 1969 and 1973. The brains of gulls dying with clinical signs of neurologic involvement, and dead gulls with no other apparent cause of death, contained organochlorine residues of significantly greater levels than those found in healthy gulls shot for comparison. PMID:410957

Sileo, L; Karstad, L; Frank, R; Holdrinet, M V; Addison, E; Braun, H E

1977-07-01

63

Investigation of spatial trends and neurochemical impacts of mercury in herring gulls across the Laurentian Great Lakes.  

PubMed

Herring gulls (Larus argentatus) bioaccumulate mercury (Hg) but it is unknown whether they are exposed at levels of neurological concern. Here we studied brain tissues from gulls at five Great Lakes colonies and one non-Great Lakes colony during spring of 2001 and 2003. Total brain Hg concentrations ranged from 0.14 to 2.0 microg/g (dry weight) with a mean of 0.54 microg/g. Gulls from Scotch Bonnet Island, on the easternmost edge of the Great Lakes, had significantly higher brain Hg than other colonies. No association was found between brain Hg concentration and [3H]-ligand binding to neurochemical receptors (N-methyl-D-aspartate, muscarinic cholinergic, nicotinic cholinergic) or nicotinic receptor alpha-7 relative mRNA expression as previously documented in other wildlife. In conclusion, spatial trends in Hg contamination exist in herring gulls across the Great Lakes basin, and herring gulls accumulate brain Hg but not at levels associated with sub-clinical neurochemical alterations. PMID:20641170

Rutkiewicz, Jennifer; Scheuhammer, Anton; Crump, Doug; Jagla, Magdalena; Basu, Niladri

2010-08-01

64

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

Microsoft Academic Search

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

Freydis Vigfusdottir; Snæbjorn Palsson; Agnar Ingolfsson

2009-01-01

65

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

Microsoft Academic Search

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

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

2006-01-01

66

Mercury levels in Great Lakes herring gull eggs, 1972--1992  

SciTech Connect

Since 1971, the herring gull (Larus argentatus) has been used as a sentinel species for monitoring the levels of persistent contaminants in the Great Lakes ecosystem. In this study, 21 herring gull colonies in the Great Lakes and connecting channels were sampled for years 1972--1976, 1981--1983, 1985 and 1992. For each year, 10 eggs (usually) were collected from each colony site and analyzed for total mercury (ppm, wet weight). Results indicated that eggs from Lake Ontario displayed the highest mercury levels, mean = 0.28 (s.d. = 0.08) to 0.73 (0.23). Lake Erie typically displayed the lowest egg mercury levels, 0.18 (0.08) to 0.24 (0.11). Overall, mercury levels ranged from 0.12 (0.02) in 1985 to 0.88 (0.23) in 1982 for Channel-Shelter Island (Lake Huron) and Pigeon Island (Lake Ontario), respectively. Generally, all colony sites showed peak mercury levels in 1982. A significant decline in egg mercury levels was observed in six colony sites between 1972 and 1992 and in three colony sites between 1981 and 1992. The mean herring gull egg mercury levels observed in the early and mid 1970s and in 1982 for some colony sites were within the range found which potentially reduces hatchability in other fish-eating bird species.

Weseloh, D.V.; Koster, M.D.; Ryckman, D.P.; Struger, J. [Canadian Wildlife Service, Burlington, Ontario (Canada). Canada Centre for Inland Waters

1995-12-31

67

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

PubMed Central

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

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

2014-01-01

68

Mapping islands, reefs and shoals in the oceans surrounding Australia  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The geometric accuracy test produced an estimate that the distortion levels on LANDSAT imagery are such that few corrections, or possibly no corrections, would be necessary in order to have the imagery satisfy accuracy specifications. It can be expected that the geometric accuracy of the low generation imagery, being used in distortion tests, in such that the distortions would cause no difficulty during the course of map preparation.

Turner, L. G. (principal investigator)

1976-01-01

69

ERDCTR-11-4 Erie Harbor, Pennsylvania, Channel Shoaling  

E-print Network

for beach nourishment or wetland restoration. The project entailed review of the dredging history at ErieERDCTR-11-4 Erie Harbor, Pennsylvania, Channel Shoaling Analysis EnvironmentalLaboratory Mansour; distribution is unlimited. #12;ERDC TR-11-4 July 2011 Erie Harbor, Pennsylvania, Channel Shoaling Analysis

US Army Corps of Engineers

70

Inner-shelf shoal formation through transgressive barrier submergence  

Microsoft Academic Search

Shore-parallel sand shoals are common depositional features on the continental shelves of North America and make up a significant component of the stratigraphic record generated by the Holocene transgression. Erosional shoreface retreat and in-place drowning of barrier shorelines are models that have been proposed to explain the generation of these deposits. Sand shoals within the retreat path of the Holocene

S. Penland; J. R. Suter; R. Boyd

1986-01-01

71

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 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

Kelley, Dan

72

Scour below marine pipelines in shoaling conditions for random waves  

Microsoft Academic Search

This paper provides an approach by which the scour depth below pipelines in shoaling conditions beneath non-breaking and breaking random waves can be derived. Here the scour depth formula in shoaling conditions for regular non-breaking and breaking waves with normal incidence to the pipeline presented by Cevik and Yüksel [Cevik, E. and Yüksel, Y., (1999). Scour under submarine pipelines in

Dag Myrhaug; Muk Chen Ong; Cecilie Gjengedal

2008-01-01

73

Sleep in the Herring Gull (Larus argentatus)  

Microsoft Academic Search

Sleep postures and eye state of free-ranging herring gulls (Larus argentatus) were studied during the breeding season. Three mutually exclusive behaviours were observed, namely sleep, rest-sleep and rest postures. Arousal thresholds, eye blink rates and eye closure time were obtained during these behaviours. Significant relationships existed between eye blinking, eye closure, and a raised threshold of arousal when birds were

Charles J. Amlaner; David J. McFarland

1981-01-01

74

SEXUAL DIMORPHISM OF LARGE GULLS (LARUS SPP.)  

Microsoft Academic Search

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): \\

AGNAR INGOLFSSON

75

THE DISTRIBUTION OF CERTAIN LARGE GULLS  

Microsoft Academic Search

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

Pierre Devillets; Guy McCaskie; Joseph R. Jehl

76

Metals in Herring and Great Black-Backed Gulls from the New York Bight: the Role of Salt Gland in Excretion  

Microsoft Academic Search

We examined the tissue distribution ofmetals in the herring (Larus argentatus) andgreat black-backed (Larus marinus) gullsobtained near the John F. Kennedy Airport, on LongIsland, New York, to determine whether there werespecies differences and whether levels in the saltgland were sufficiently high to suggest that thisorgan may be serving an excretory function. For mostorgans, herring gulls had significantly higher levelsof lead

Joanna Burger; Chirag D. Trivedi; Michael Gochfeld

2000-01-01

77

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

Microsoft Academic Search

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

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

2000-01-01

78

Long-term morphological response to dredging including cut-across-shoal in a tidal channel-shoal system  

NASA Astrophysics Data System (ADS)

This study examines long-term channel-shoal stability in the Tieshan Bay, which is located on the southwest coast of China. A large-scale channel-shoal system has historically existed in the outer Tieshan Bay. A navigation waterway is initiated by cutting and dredging a mid-channel shoal to supply coal to a power plant on the middle coast of the Tieshan Bay. Dredging of the access channel to the Tieshan Port was conducted in two stages followed by land reclamation. It is thus of practical meaning to explore how the channel-shoal system will evolve in long term afterwards. This study uses the process-based finite-volume coastal ocean model (FVCOM) to investigate long-term (centennial) morphological evolution of the channel-shoal system. After well calibration of hydrodynamics and sediment transport, the model forecasts morphodynamic evolution in hundred years. The simulations show that continuous erosion in tidal channels and accretion over shoals and intertidal flats occur. However, the cutting and access channels will be subjected to long-term siltation. A secondary channel indicating the reorientation of the access channel will emerge, and a localized channel-ridge system at the junction of the major channels will be formed. The overall erosion/accretion pattern demonstrates the combined effect of bottom friction and advective sediment transport processes to be responsible for the channel-shoal formation. Dredging of the tidal channels will stimulate the stability of the channel-shoal pattern. It suggests that the navigation waterway should be set up following the long-term morphological evolution of the channel-shoal system at a design stage and maintenance dredging volume might thus be minimized.

Wang, Yu-Hai; Wang, Chong-Hao; Tang, Li-Qun; Liu, Da-Bin; Guo, Chuan-Sheng; Liu, Chun-Jing; Zhao, Hui-Ming

2014-12-01

79

A TECHNIQUE TO COLOR-MARK INCUBATING GULLS  

Microsoft Academic Search

Modification of a method used to mark Cattle Egrets (Bubulcus ibis) produced a technique suitable for color-marking Herring (Larus argentatus), Great Black-backed (L. marinus), and Laughing (L. atricilla) Gulls. Gulls marked themselves while incubating artificial eggs treated with a mixture of petroleum jelly and Rhodamine B. Marks persisted on gulls a minimum of 28-42 d. Low levels of mortality (0.05-0.27%)

PAUL M. CAVANAGH; CURTICE R. GRIFFIN; EDWIN M. HOOPES

80

Nutrient transfer from sea to land: the case of gulls and cormorants in the Gulf of Maine.  

PubMed

1. The structure of communities is influenced by the transport of resources across ecosystem boundaries. Seabirds are capable of introducing large amounts of marine-derived nutrients to land, thereby modifying resource availability to terrestrial species. 2. In this study we investigated the hypothesis that variation in nesting densities of great black-backed gulls Larus marinus and double-crested cormorants Phalacrocorax auritus would modify the effect of these species on soil nutrients and plant species composition on offshore islands in the Gulf of Maine, USA. 3. Our results showed a significant positive correlation between nest density and concentrations of ammonia and nitrate in soils, but no significant relationship between nest density and phosphate. Ammonia and phosphate concentrations were good predictors of plant species composition; there were more annual forbs than perennial grasses in the abandoned cormorant colony compared with the gull colonies. Extremely high concentrations of ammonia in the highest density colony (active cormorant) may have been the main factor inhibiting plant germination at this site. All of the plant species in gull and cormorant colonies showed enriched delta(15)N signatures, indicating substantial input of marine-derived nitrogen from seabirds. 4. Our study demonstrated that gulls and cormorants are effective vectors for the transport of marine nutrients to terrestrial ecosystems. However, transported nutrients occurred in particularly high concentrations in areas with nesting cormorants. Nesting densities and species-specific variation in resource transport should be considered when predicting the effects of seabirds and other biogenic vectors of allochthonous resources. PMID:16638009

Ellis, Julie C; Fariña, Jose Miguel; Witman, Jon D

2006-03-01

81

Shoaling of nonlinear internal waves in Massachusetts Bay  

USGS Publications Warehouse

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.

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

2008-01-01

82

Indexing winter gull numbers in Great Britain using data from the 1953 to 2004 Winter Gull Roost Surveys  

Microsoft Academic Search

Capsule Winter Gull Roost Survey data spanning 50 years were used to generate population indices.Aims To evaluate how wintering numbers of five gull species have changed in Great Britain over the last five decades.Methods Generalized linear models were used to relate gull numbers to habitat, site and year factors, and so derive species?specific indices for nine regions of Great Britain.

Alexander N. Banks; Niall H. K. Burton; John R. Calladine; Graham E. Austin

2009-01-01

83

Shoaling enhances cadmium avoidance by lake whitefish, Coregonus clupeaformis  

Microsoft Academic Search

We compared the behavioural responses of solitary and shoaling lake whitefish, Coregonus clupeaformis, to Cd solutions, testing the hypothesis that fish are more responsive to contaminant gradients when in a shoal than when alone. The movements of individual fish were tracked in a countercurrent-type trough with clean water on one side, and water containing sequentially increasing Cd concentrations (0.2–125 µg

Richard E. McNicol; Eberhard Scherer; John H. Gee

1996-01-01

84

Flow separation and resuspension beneath shoaling nonlinear internal waves  

Microsoft Academic Search

Laboratory observations are presented showing the structure and dynamics of the turbulent bottom boundary layer beneath nonlinear internal waves (NLIWs) of depression shoaling upon sloping topography. The adverse pressure gradient beneath the shoaling waves causes the rear face to steepen, flow separation to occur, and wave-induced near-bottom vortices to suspend bed material. The resuspension is directly attributed to the near-bed

Leon Boegman; Gregory N. Ivey

2009-01-01

85

Contaminant levels in Herring (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs from colonies in the New York harbor complex between 2012 and 2013.  

PubMed

Birds living in coastal areas are exposed to severe storms and tidal flooding during the nesting season, but also to contaminants that move up the food chain from the water column and sediment to their prey items. We examine metals in Herring Gull (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs collected from the New York/New Jersey harbor estuary in 2012 and in 2013 to determine if there were significant yearly differences in metal levels. We test the null hypothesis that there were no significant yearly differences in metal levels. We investigate whether there were consistent differences in metals from 2012 to 2013 that might suggest a storm-related effect because Superstorm Sandy landed in New Jersey in October 2012 with high winds and extensive flooding, and view this research as exploratory. Except for arsenic, there were significant inter-year variations in the mean levels for all colonies combined for Herring Gull, and for lead, mercury and selenium for Great Black-backed Gulls. All metal levels in 2013 were less than in 2012, except for lead. These differences were present for individual colonies as well. Metal levels varied significantly among islands for Herring Gulls in both years (except for cadmium in 2013). No one colony had the highest levels of all metals for Herring Gulls. A long term data set on mercury levels in Herring Gulls indicated that the differences between 2012 and 2013 were greater than usual. Several different factors could account for these differences, and these are discussed. PMID:25471353

Burger, Joanna; Elbin, Susan

2014-12-01

86

Molecular characterization of novel circoviruses from finch and gull  

Microsoft Academic Search

The purpose of this study was to molecularly characterize circoviruses that infect finches and gulls. Circovirus-specific DNAs were isolated using polymerase chain reaction methods from bursa of Fabricius tissues from a Gouldian finch (Chloebiagouldiae) and a herring gull (Larus argentatus) that were known to be circovirus-infected. Nucleotide sequence determination and analysis of cloned genomic DNAs showed that these circoviruses represented

D. Todd; A. N. J. Scott; E. Fringuelli; H. L. Shivraprasad; D. Gavier-Widen; J. A. Smyth

2007-01-01

87

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

Microsoft Academic Search

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

Gregory T. Ruggerone

1986-01-01

88

COMPETITION BETWEEN AMERICAN COOTS AND FRANKLIN'S GULLS FOR NEST SITES AND EGG PREDATION BY THE COOTS  

Microsoft Academic Search

RANKLIN'S Gull (Lams pipixcan) is the only gull that nests exclusively in marshes. It is colonial, and often changes colony sites from year to year. Franklin's Gulls build semi-floating nests in the cattail (Typha sp.) marshes of the northern prairies of North America. I studied the breeding adapta- tions of the Franklin's Gull to a marsh habitat from 1968 to

JOANNA BURGER

89

Nitrite poisoning in herring gulls (Larus argentatus) and ring-billed gulls (Larus delawarensis).  

PubMed

Landfill disposal of a fertilizer manufacturing waste product was associated with a die-off of gulls in New Hanover County, North Carolina. An estimated 250 herring and ring-billed gulls were found dead at the site following the initial disposal of this material. Chemical analyses revealed that the fertilizer waste contained predominately calcium (12.0 to 22.2%) and nitrite (3.0 to 15.2%). Contents of the proventriculi and gizzards of dead gulls also contained calcium (3.0 to 10.9%) and nitrite (1,730 ppm). Fertilizer waste administered orally to 16-day-old domestic turkeys resulted in acute, progressive signs of depression, respiratory distress, pallor, convulsions and death. The mean percentage methemoglobin in blood from convulsing turkeys (90.6) was significantly increased from that of normal control turkeys (3.6). The ante-mortem signs and increased blood methemoglobin concentrations in the experimental turkeys support the conclusion that the toxic principle in the fertilizer waste was nitrite, and that nitrite poisoning was the cause of the die-off of gulls. PMID:3016349

Ley, D H

1986-07-01

90

Intergradation between the Herring Gull Larus argentatus and the Southern Herring Gull Larus cachinnans in European Russia  

Microsoft Academic Search

Five gull populations along a 2000-km transect, running from the Barents Sea coast in the Kola Pen- insula to Nizhegorodskaya oblast, were studied with respect to external morphology, vocalization, and DNA features. The transect crosses the easternmost part of the L. argentatus range, as well as areas of the Middle Volga basin inhabited by the gulls of cachinnans- like type.

E. N. Panov; D. G. Monzikov

91

CONTROL OF RING-BILLED GULLS AND HERRING GULLS NESTING AT URBAN AND INDUSTRIAL SITES IN ONTARIO, 1987-1990  

Microsoft Academic Search

Large numbers of ring-billed gulls (Larus delawarensis) and much smaller numbers of herring gulls (L. argentatus) have begun to nest at several industrial and urban sites in the Canadian Great Lakes causing a flight safety problem (nesting at end of a runway), disrupting commercial operations (nesting on roads and storage yards), and creating nuisances (noise and smell of the colony

Hans Blokpoel; Gaston D. Tessier

1991-01-01

92

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

USGS Publications Warehouse

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).

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

93

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

PubMed

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

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

2005-07-01

94

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

PubMed

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

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

2006-01-01

95

Shoaling develops with age in Zebrafish (Danio rerio)  

PubMed Central

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

Buske, Christine; Gerlai, Robert

2010-01-01

96

At–Sea Behavior Varies with Lunar Phase in a Nocturnal Pelagic Seabird, the Swallow-Tailed Gull  

PubMed Central

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. PMID:23468889

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

2013-01-01

97

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

USGS Publications Warehouse

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.

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

2013-01-01

98

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

Microsoft Academic Search

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

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

1982-01-01

99

Assessing social behavior phenotypes in adult zebrafish: shoaling, social preference and mirror biting tests  

E-print Network

1 Assessing social behavior phenotypes in adult zebrafish: shoaling, social preference their shoaling behaviors. Zebrafish also display strong social preference when placed in a tank with conspecific, social preference and mirror biting tests - for quantifying social behaviors in adult zebrafish

Kalueff, Allan V.

100

Aerodynamic implications of gull's drooped wing-tips.  

PubMed

When in gliding flight, gulls are observed to adopt a drooped wing-tip configuration. This paper investigates whether this configuration might represent an aerodynamic optimum or if it is the result of constraints imposed by the gull's anatomy. A computational model was developed for the aerodynamic performance of a gull in gliding flight. This model was used in conjunction with both global and local optimizers to determine the most aerodynamically optimal configuration for cases where the gull was constrained to move its wing within its natural flapping cycle as well as when the wing had full freedom of motion. The results of this analysis determined the best wing configuration for a gull in gliding flight and demonstrated that such a configuration not only had the highest lift-to-drag ratio but also could be achieved within the constraints of the kinematics of the gull wing. These results are of interest outside studies of gulls, since the drooped wing-tip configuration could be relevant for new designs of small air vehicles. PMID:24106263

Andrews, S A; Perez, R E; Allan, W D E

2013-12-01

101

Automatic shoal recognition and classification based on MOVIES-B software  

Microsoft Academic Search

MOVIES-B software developed by IFREMER (Institut Francais de la Recherche pour l'Exploitation de la Mer), enables the recognition of echogram features as acoustic detection structures according to spatial-energetic contiguity criteria. These structures (shoals, plankton layers) are described by energetic, morphological, spatial and temporal descriptors. Specifying acoustic detections as individual shoals will allow shoal-by-shoal echo-integration and may lead to better biomass

C. Scalabrinl; N. Diner; A. Weil

1994-01-01

102

TECHNICAL REPORT SERIES Internal waves and internal solitones shoaling  

E-print Network

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

Thiem, Ã?yvind

103

Incipient Sediment Movement by Shoaling Internal Gravity Waves  

Microsoft Academic Search

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

D. A. Cacchione; J. B. Southard

1974-01-01

104

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

E-print Network

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

Sutherland, Bruce

105

Seafloor character and sedimentary processes in eastern Long Island Sound and western Block Island Sound  

NASA Astrophysics Data System (ADS)

Multibeam bathymetric data and seismic-reflection profiles collected in eastern Long Island Sound and western Block Island Sound reveal previously unrecognized glacial features and modern bedforms. Glacial features include an ice-sculptured bedrock surface, a newly identified recessional moraine, exposed glaciolacustrine sediments, and remnants of stagnant-ice-contact deposits. Modern bedforms include fields of transverse sand waves, barchanoid waves, giant scour depressions, and pockmarks. Bedform asymmetry and scour around obstructions indicate that net sediment transport is westward across the northern part of the study area near Fishers Island, and eastward across the southern part near Great Gull Island.

Poppe, L. J.; Digiacomo-Cohen, M. L.; Smith, S. M.; Stewart, H. F.; Forfinski, N. A.

2006-06-01

106

Birds of Bylot Island and Adjacent Baffin Island,  

E-print Network

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 Arctic Archipelago (killdeer Charadrius vociferus; mew gull Larus canus). Two species, Canada goose (Branta canadensis) and red knot (Calidris canutus), were also confirmed as breeders for the first time in the region. A summary of these avifaunal observations, along with a review of previous observations made in the region, allows changes in population size and status of individual species to be identified. These records combined with those from earlier studies give a total of 74 species for the Bylot Island region, 45 confirmed as breeders. This makes the avian community in the area one of the most diverse known north of 70?N latitude in the Canadian Arctic Archipelago.

Denis Lepage; David N. Nettleship; Austin Reed

1997-01-01

107

Shoal behaviour and maturity relations of spawning capelin (Mallotus villosus )o ff Newfoundland: demersal spawning and diel vertical movement patterns  

Microsoft Academic Search

We investigated shoals of capelin (Mallotus villosus), the focal forage fish species in the Northwest Atlantic, in nearshore Newfoundland during spawning (2000-2003). Large shoals of maturing capelin were observed in warm (>0 °C), deep (>240 m) water. Smaller shoals of maturing fish were located in two specific areas closer to shore in shallower water (100-150 m). Shoals persisted in these

Gail K. Davoren; John T. Anderson; William A. Montevecchi

108

Expansion of the Mediterranean Gull Larus melanocephalus in Poland  

Microsoft Academic Search

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.

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

2007-01-01

109

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

PubMed

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

Kennedy, C R; Bakke, T A

1989-06-01

110

A Second Breeding Site for Ross’s Gull (Rhodostethia rosea  

E-print Network

ABSTRACT. 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 one pair incubating two eggs on a small island (30 m in diameter) situated in a medium-sized lake, on a low plateau at the top of a complex of raised beaches. None of the reports on aerial or land surveys of this region have mentioned the reproduction of this species, though unpublished aerial observations suggest that the species has been present during the 1980s. Outside Siberia, this species seems to be characterized by an irregular and scattered distribution of its breeding sites. Key words: Ross’s gull, Rhodostethia rosea, breeding site, Foxe Basin, Prince Charles Island, Nunavut RÉSUMÉ. Seuls 15 cas de reproduction de la mouette de Ross Rhodostethia rosea ont été rapportés en dehors de la Sibérie. Alors que de nombreux oiseaux sont observés à l’automne lors de leur passage à Point Barrow (Alaska), la reproduction au Nunavut (Canada) n’a été mentionnée qu’une seule fois. Nous documentons un deuxième site de reproduction pour le Nunavut, dans la partie nord-ouest de l’île du Prince-Charles (bassin Foxe). Un couple a été observé incubant deux œufs sur une petite île (environ 30 m de diamètre) située au milieu d’un lac de taille moyenne, sur un plateau bas constituant le sommet d’un complexe de plages surélevées. Aucun des rapports des levés aériens ou terrestres de cette région ne mentionne la reproduction de cette espèce, bien que des observations aériennes non publiées suggèrent sa présence au cours des années 80. En dehors de la Sibérie, cette espèce

Peter Meister; Corinne Rabouam

1999-01-01

111

Linear and branched perfluorooctane sulfonate isomer patterns in herring gull eggs from colonial sites across the Laurentian Great Lakes.  

PubMed

Linear and branched (six mono(trifluoromethyl) and four di(trifluoromethyl)) isomers of the bioaccumulative contaminant perfluorooctane sulfonate (PFOS) were analyzed for and the spatial patterns examined in individual herring gull (Larus argentatus) eggs (n = 13 per site) collected (in 2007) from 15 colonies across the Laurentian Great Lakes of North America. Linear PFOS (n-perfluoro-1-octanesulfonate (L-PFOS)) consistently dominated the isomer pattern in all eggs, comprising between 95.0% and 98.3% of the summation sigmaPFOS concentration. L-PFOS was highly enriched in the gull eggs as the summation sigmabranched-PFOS to L-PFOS isomer concentration ratios were very constant (overall average 0.038 +/- 0.001) and much lower compared to technical PFOS (range 0.27-0.54). The highest proportions of L-PFOS were generally observed in the eggs from the lower lakes (Erie and Ontario) colonies. All six mono(trifluoromethyl) branched isomers, or perfluoro-n-methyl-heptanesulfonates where n describes the carbon of the hydrocarbon chain were there is trifluoromethyl substitution relative to the sulfonate terminal group, were detected in the eggs from all the colonies. For example, P1MHpS is perfluoro-1-methyl-heptanesulfonate. Comparable to technical PFOS (T-PFOS), the percentage of the mono(trifluoromethyl) isomer to summation sigmaPFOS concentration decreased as the branch substitution was located closer to the sulfonate group, that is, P6MHpS (0%-2.5%), P5MHpS (0.43%-1.18%), P4MHpS (0.25%-0.69%), and P3MHpS (0.32%-0.74%). Although at even lower fractional composition than the mono(trifluoromethyl) isomers, of the di(trifluoromethyl) isomers, detected in >60% of the individual eggs per site was P35DMHxS and P45DMHxS for Toronto Harbour (Lake Ontario), P35DMHxS for Chantry (Lake Huron) and Fighting Island (Detroit River), and P45DMHxS for Gull Island (Lake Michigan). Relative to T-PFOS, and independent of colonial location, the high and consistent enrichment of L-PFOS in gull eggs is likely a function of several processes including PFOS or precursor sources, and isomer-specific PFOS or precursor exposure, accumulation, biotransformation, retention and/or elimination. The results of this study suggests that the apparent dilution of the mono(fluoromethyl) isomers from environmental processes that occur prior to final accumulation in herring gull eggs, is independent of the mono(fluoromethyl) isomer structure. PMID:20415439

Gebbink, Wouter A; Letcher, Robert J

2010-05-15

112

POLLUTANT CONCENTRATIONS IN ABNORMAL YOUNG TERNS FROM LONG ISLAND SOUND  

Microsoft Academic Search

THS paper reports the results of preliminary analyses for chlorinated hydrocarbons and mercury in young terns with visible abnormalities fo.und in a colony on Great Gull Island, 72 ø 07' W, 41 ø 12' N. Analyses are also reported on eight species of fish brought to the colony as food for the young or as part of behavioral displays. Great

HELEN HAYS; ROBERT W. RISEBROUGH

113

Delayed capelin (Mallotus villosus) availability influences predatory behaviour of large gulls on  

E-print Network

, the impact of predation by herring gulls (Larus argentatus) and great black-backed gulls (Larus marinus argenté (Larus argentatus) et le Goéland à manteau noir (Larus marinus) sur la succès de la reproduction), and herring gulls (Larus argentatus; Pierotti and Annett 1987). Because of below- normal sea temperatures

Jones, Ian L.

114

Net energy versus efficiency maximizing by foraging ring-billed gulls  

Microsoft Academic Search

Ring-billed gulls (Larus delawarensis) breeding at Dog Lake, Manitoba often feed by following tractors pulling cultivating implements around fields. Tractor-following gulls always land immediately behind the cultivating implement, where they feed on earthworms or grain. Afeer a feeding bout on the ground (patch residence time), gulls fly up, pursue the tractor and repeat the cycle. We use net energy maximizing

C. V. J. Welham; R. C. Ydenberg

1988-01-01

115

Importance of landfills to urban-nesting herring and ring-billed gulls  

Microsoft Academic Search

Little information exists on the importance of landfills to urban gulls and the influence landfills have on the establishment of urban-nesting gull colonies. Thus, there is critical need for data to determine factors contributing to increasing populations of urban gulls. Our objectives were to determine the importance of landfills to the reproductive success, diet, and movements (via radio telemetry) of

Jerrold L Belant; Sheri K Ickes; Thomas W Seamans

1998-01-01

116

Impact of the ring-billed gull (Larus delawarensis) on the microbiological quality of recreational water.  

PubMed Central

We evaluated the impact of the ring-billed gull (Larus delawarensis) on the microbiological quality of water. We measured fecal coliforms, Salmonella spp., and Aeromonas spp. in the gull droppings and the number of fecal coliforms in the water prior to and after attracting these birds to the beach with food. Gulls can contribute to the bacteriological degradation of recreational water. PMID:8489231

Benoît Leévesque; Brousseau, P; Simard, P; Dewailly, E; Meisels, M; Ramsay, D; Joly, J

1993-01-01

117

Impact of the ring-billed gull (Larus delawarensis) on the microbiological quality of recreational water.  

PubMed

We evaluated the impact of the ring-billed gull (Larus delawarensis) on the microbiological quality of water. We measured fecal coliforms, Salmonella spp., and Aeromonas spp. in the gull droppings and the number of fecal coliforms in the water prior to and after attracting these birds to the beach with food. Gulls can contribute to the bacteriological degradation of recreational water. PMID:8489231

Benoît Leévesque; Brousseau, P; Simard, P; Dewailly, E; Meisels, M; Ramsay, D; Joly, J

1993-04-01

118

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

Microsoft Academic Search

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

J. W. Portnoy; Cape Cod; M. A. Soukup

1990-01-01

119

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

Microsoft Academic Search

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,

U. Kubetzki; S. Garthe

2003-01-01

120

Sources of Food Delivered to Ring-Billed, Herring and Great Black-Backed Gull Chicks in Marine Environments  

E-print Network

.--Beginning in the 1960s, Ring-billed Gulls' (Larus delawarensis) historic breeding range expanded from inland habitats words.--diet, Great Black-backed Gull, Herring Gull, Larus argentatus, Larus delawarensis, Larus marinus Ring-billed Gulls (Larus delawarensis) his- torically nested near freshwater and had a breeding range

Shutler, Dave

121

Cestodes of the genus Aploparaksis Clerc, 1903 (Cyclophyllidea, Aploparaksidae) reported from gulls, with a description of new species  

Microsoft Academic Search

Fifteen species of Aploparaksis Clerc, 1903 described from gulls or reported to infect gulls are reviewed. The re?examination showed that gulls are parasitised by the following six species: A. borealis, A. brachyphallus, A. diagonalis, A. rissae, A. xemae and A. shigini n. sp. Only the latter species is considered to be a host?specific parasite of gulls, whereas A. borealis is

Svetlana Bondarenko; Vytautas Kontrimavichus

2006-01-01

122

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

USGS Publications Warehouse

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).

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

1999-01-01

123

[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

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

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

2005-01-01

124

Herring gulls and great black-backed gulls as indicators of contaminants in bald eagles in Lake Ontario, Canada.  

PubMed

In 2000, a pair of bald eagles (Haliaeetus leucocephalus) nested successfully along the shorelines of Lake Ontario in North America for the first time since 1957. However, it is a continuing question whether bald eagles will be able to reproduce successfully as they return to nest on Lake Ontario. Great black-backed gulls (Larus marinus) and herring gulls (L. argentatus) were selected as surrogate species to predict contaminant levels in eggs of bald eagles nesting on Lake Ontario. Because of the suspected overlap in the diets of great black-backed gulls and bald eagles (i.e., fish, gull chicks, and waterfowl), the two species probably occupy a similar trophic level in the Lake Ontario food web and, thus, may have similar contaminant levels. Fresh great black-backed gull and herring gull eggs were collected from three study sites in eastern Lake Ontario in 1993 and 1994 and analyzed for contaminants. Average contaminant levels of dichlorodiphenyldichloroethane (p,p'-DDE), total polychlorinated biphenyls (PCBs), and dieldrin in great black-backed gull eggs were 12.85, 26.27, and 0.27 microg/g, respectively. The mean ratio of contaminant levels in great black-backed gull eggs to contaminant levels in herring gull eggs for these three contaminants was 2.09 (range of means, 1.73-2.38). Predicted levels of contaminants in bald eagle eggs in Lake Ontario would be expected to be similar to the mean levels reported for great black-backed gull eggs. As a comparison, contaminant levels in bald eagle eggs collected from other Great Lakes nesting sites were compared to mean levels reported for herring gull eggs collected from nearby sites in 1986 to 1995. The mean ratio of contaminant levels in bald eagle eggs to contaminant levels in herring gull eggs from these sites for DDE, total PCBs, and dieldrin was 2.40 (range of means, 1.73-3.28). These ratios are very similar to those reported using great black-backed gull eggs, illustrating the apparent similarity in trophic status shared by the two top predator species at these Great Lakes sites. Predicted levels of contaminants in bald eagle eggs at Lake Ontario are similar to levels reported for bald eagles breeding at other Great Lakes sites, suggesting that bald eagles may be able to breed on the shores of Lake Ontario. However, it is unclear at this time what level of breeding success should be expected, given that productivity at other similarly contaminated Great Lakes sites may be below that required to sustain a successful breeding population. The absence of an inland bald eagle population from which bald eagles may begin to colonize the shorelines of Lake Ontario may be delaying initiation of nesting site selection; other factors such as habitat and prey availability would likely not limit reproductive success. PMID:12013123

Weseloh, D Vaughn; Hughes, Kimberly D; Ewins, Peter J; Best, Dave; Kubiak, Timothy; Shieldcastle, Mark C

2002-05-01

125

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

PubMed

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

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

2005-11-01

126

Characterization of a novel haemagglutinin subtype (H13) of influenza A viruses from gulls*  

PubMed Central

Influenza A virus strains isolated in the United States of America from ring-billed and Franklin gulls (Larus delawarensis, L. pipixcan) were found to possess a haemagglutinin (HA) antigen distinct from those of the twelve previously designated haemagglutinin subtypes of influenza A virus. Serological assays with antisera to reference strains representing the HA subtypes 1-12 and to a gull isolate, A/gull/Maryland/704/77, showed that the haemagglutinin of the gull virus was not related antigenically to the previously designated subtypes. In addition, comparison of the nucleotide sequences, and deduced amino acid sequences, of the 3? region of the RNA genes coding for haemagglutinin indicated that the gull viruses represent a genetically distinct group. We propose that this new HA antigen, which has so far been detected only in gulls, be designated H13 and that A/gull/Maryland/704/77 (H13N6) be designated the reference strain for this subtype. PMID:6194911

Hinshaw, V. S.; Air, G. M.; Schild, G. C.; Newman, R. W.

1983-01-01

127

Characterization of a novel haemagglutinin subtype (H13) of influenza A viruses from gulls.  

PubMed

Influenza A virus strains isolated in the United States of America from ring-billed and Franklin gulls (Larus delawarensis, L. pipixcan) were found to possess a haemagglutinin (HA) antigen distinct from those of the twelve previously designated haemagglutinin subtypes of influenza A virus. Serological assays with antisera to reference strains representing the HA subtypes 1-12 and to a gull isolate, A/gull/Maryland/704/77, showed that the haemagglutinin of the gull virus was not related antigenically to the previously designated subtypes. In addition, comparison of the nucleotide sequences, and deduced amino acid sequences, of the 3' region of the RNA genes coding for haemagglutinin indicated that the gull viruses represent a genetically distinct group. We propose that this new HA antigen, which has so far been detected only in gulls, be designated H13 and that A/gull/Maryland/704/77 (H13N6) be designated the reference strain for this subtype. PMID:6194911

Hinshaw, V S; Air, G M; Schild, G C; Newman, R W

1983-01-01

128

Flatfish selection by herring gulls Larus argentatus and lesser black-backed gulls Larus fuscus scavenging at commercial beamtrawlers in the southern North Sea  

NASA Astrophysics Data System (ADS)

Flatfish selection by scavenging herring gulls and lesser black-backed gulls was studied onboard a commercial beamtrawler in the southern North Sea, June2 -August 1993. Dab (median total length 18 cm), plaice (23 cm), sole (22 cm) and solenette (10 cm) dominated the flatfish discard fraction of the catch. The overall consumption amounted to 30.5% of the discarded flatfish. Flatfish were selected on the basis of fish width rather than length or species, with very low consumption rates (percentage consumed of number offered) of flatfish >8 cm width. All discarded solenette, 98% of all sole and 92% of all dab were of suitable size for these gulls, whereas only 12% of all discarded plaice were small enough to be consumed. Consumption rates of discarded flatfish of 'suitable size' for herring gulls and lesser black-backed gulls (<8 cm width) ranged from 25.9% (plaice) to 40.5% (dab). Success indices and selected size classes of flatfish in scavenging herring gulls and lesser black-backed gulls feeding on flatfish were similar, but the first were more efficient than the latter and lost fewer flatfish as a consequence of kleptoparasitism. In contrast to earlier suggestions (based on dietary studies in colonies), there was no evidence that herring gulls were outcompeted by lesser black-backed gulls when feeding on discarded fish.

Camphuysen, C. J.(Kees)

129

[Morpho-functional changes of cloacal bursa of the herring gull in experimental infection with gull tapeworm].  

PubMed

Using the methods of light microscopy, the quantitative changes in the cells of the cloacal bursa of herring gull (Larus argentatus mongolicus) chicks were studied during experimental infection with gull-tapeworm Diphyllobothrium dendriticum. The area of the follicles within the bursa and the number of eosinophils in the infected chicks were found to increase. In the follicles the number of blast cells and large lymphocytes was elevated. The reduction of small lymphocytes and plasma cells numbers in the infected gulls may be due to a slower cell cycle or cell migration into the inflammatory focus. Overall, the changes in the bursa indicate the suppression of the B-link of the host immune system in tapeworm invasion. PMID:22724332

Fomina, A S; Pronina, S V

2012-01-01

130

How much did Glacial North Atlantic Water shoal?  

NASA Astrophysics Data System (ADS)

Observations of ?13C and Cd/Ca from benthic foraminifera have been interpreted to reflect a shoaling of northern source waters by about 1000 m during the Last Glacial Maximum, with the degree of shoaling being significant enough for the water mass to be renamed Glacial North Atlantic Intermediate Water. These nutrient tracers, however, may not solely reflect changes in water mass distributions. To quantify the distribution of Glacial North Atlantic Water, we perform a glacial water mass decomposition where the sparsity of data, geometrical constraints, and nonconservative tracer effects are taken into account, and the extrapolation for the unknown water mass end-members is guided by the modern-day circulation. Under the assumption that the glacial sources of remineralized material are similar to that of the modern day, we find a steady solution consistent with 241 ?13C, 87 Cd/Ca, and 174 ?18O observations and their respective uncertainties. The water mass decomposition indicates that the core of Glacial North Atlantic Water shoals and southern source water extends in greater quantities into the abyssal North Atlantic, as previously inferred. The depth of the deep northern-southern water mass interface and the volume of North Atlantic Water, however, are not grossly different from that of the modern day. Under this scenario, the vertical structure of glacial ?13C and Cd/Ca is primarily due to the greater accumulation of nutrients in lower North Atlantic Water, which may be a signal of the hoarding of excess carbon from the atmosphere by the glacial Atlantic.

Gebbie, Geoffrey

2014-03-01

131

Social familiarity and shoal formation in juvenile fishes.  

PubMed

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

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

2010-02-01

132

Macrofauna on flood delta shoals in the Wadden Sea with an underground association between the lugworm Arenicola marina and the amphipod Urothoe poseidonis  

NASA Astrophysics Data System (ADS)

Living conditions for macrofauna on flood delta shoals are determined by surf, strong currents and sediment mobility. Thus, a unique assemblage of invertebrate species colonize these far off-shore, low intertidal flats. We here describe the macrobenthic fauna of emerging shoals in the Wadden Sea between the islands of Römö and Sylt. Besides ubiquitous macroinvertebrates of the intertidal zone and species which attain their main distribution in the subtidal zone, the flood delta shoals are characterized by organisms adapted to live in these highly unstable sediments, like the polychaetes Spio martinensis, Streptosyllis websteri, Magelona mirabilis, Psammodrilus balanoglossoides, the pericarid crustaceans Cumopsis goodsiri, Tanaissus lilljeborgi, Bathyporeia sarsi and a few others. Average abundance (1440 m-2 of ind >1 mm) and biomass (12.9 g AFDW m-2) were low compared to other intertidal habitats in the Wadden Sea. Biomass was dominated by largesized individuals of the lugworm Arenicola marina. The U-shaped burrows of these polychaetes were inhabited by high numbers of Urothoe poseidonis. Maximum densities of these amphipods occurred in the deepest parts of the burrows. Sampling at approximately montly intervals revealed no apparent seasonality of U. poseidonis abundance. Together with small Capitella capitata, these amphipods constitute a deep-dwelling component of the macrofauna associated with lugworms, which is separated from all other macrofauna living at the sediment surface. As a response to rising sea level and increasing tidal ranges, we expect the unstable sandy shoals, inhabited by numerous Spio martinensis and Urothoe poseidonis, to expand within the Wadden Sea at the cost of stable sandy flats with abundant macrofauna.

Lackschewitz, D.; Reise, K.

1998-06-01

133

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

E-print Network

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

US Army Corps of Engineers

134

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

E-print Network

Response of individual shoaling Atlantic cod to ocean currents on the northeast Newfoundland Shelf 16 August 1999 Abstract The movements of sonically-tagged Atlantic cod swimming within a large (80 of the shoal. Then, apparently in response to a shoreward current event, the cod moved with the ¯ow. The tagged

deYoung, Brad

135

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

136

The herring gull complex is not a ring species.  

PubMed

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

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

2004-05-01

137

Immune Function and Organochlorine Pollutants in Arctic Breeding Glaucous Gulls  

Microsoft Academic Search

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

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

2004-01-01

138

IDENTIFICATION AND MOLT OF HYBRID GLAUCOUS-WINGED GULLS  

Microsoft Academic Search

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

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

1998-01-01

139

POTENTIAL FOR GULLS TO TRANSPORT BACTERIA FROM HUMAN WASTE SITES  

EPA Science Inventory

This study was designed as a first step in assessing whether gulls visiting human waste sites can acquire human microorganisms and distribute them across the coastal landscape. Beaches, landfills, and a lagoon of treated wastewater located in a coastal Lake Michigan county were t...

140

Spatial patterns and rankings of contaminant concentrations in Herring Gull eggs from 15 sites in the Great Lakes and connecting channels, 1998-2002.  

PubMed

Mean values of eight contaminants in Herring Gull (Larus argentatus) eggs were calculated for 15 Great Lakes sites for the 5 year period 1998-2002. The sites were ranked according to the concentrations of each of seven compounds relative to fish flesh criteria for the protection of piscivorous wildlife, and a single overall rank of contamination was calculated for each site. Based on this weighted ranking scheme, we found that sum PCBs, dioxin and DDE contributed the most (60.2, 30.5% and 8.5%, respectively) to the overall rankings. The weighted ranking scheme showed that eggs from Channel-Shelter Island (Saginaw Bay, Lake Huron), Strachan Island (St. Lawrence River) and Gull Island (northern Lake Michigan) ranked as the three most contaminated sites, while Agawa Rocks (eastern Lake Superior), Chantry Island (southern Lake Huron) and Port Colborne (eastern Lake Erie) ranked as the three least contaminated sites. Two of the three most contaminated sites are Areas of Concern; none of the three least contaminated sites are Areas of Concern. PMID:16491432

Weseloh, D V Chip; Pekarik, Cynthia; De Solla, Shane R

2006-02-01

141

Jamaica Bay studies III: Abiotic determinants of distribution and abundance of gulls ( Larus)  

NASA Astrophysics Data System (ADS)

The distribution and abundance of gulls were examined at Jamaica Bay Wildlife Refuge (New York) from 31 May 1978 to 31 May 1979. Gulls were found to be affected by tidal, temporal and weather-related factors. The distribution of gulls was affected primarily by tidal factors on the bay, and by temporal (seasonal, circadian) and weather-related factors on the freshwater ponds. The most important weather-related factors were temperature, wind velocity and wind direction. Herring ( L. argentatus), great black-backed ( L. fuscus) and ring-billed gulls ( L. delawarensis) fed on the bay at low tides, and used the ponds at high tide. Laughing gulls ( L. atricilla) fed on the bay at low tide and on rising tides. Herring and great black-backed gulls were present all year, but were most abundant in the winter, ring-billed gulls were abundant in spring and early fall, and laughing gulls were present in the summer following the breeding season but were absent in winter. Gulls used the ponds during high velocity, north winds, when they usually rested or preened. Multiple regression models were used to determine the factors explaining the variability in the numbers of gulls. Temporal variables were important contributors to accounting for the variability in the numbers of great black-backed and herring gulls only; tidal variables were significant for great black-backed and herring gulls on the bay, and for ring-billed and laughing gulls on all areas; and weather variables were significant for all species.

Burger, Joanna

1983-02-01

142

Association patterns and shoal fidelity in the three-spined stickleback.  

PubMed Central

We investigated pairwise association patterns and shoal fidelity in free-ranging, individual three-spine sticklebacks (Gasterosteus aculeatus) by capturing entire shoals of sticklebacks and tagging each shoal member with a unique individual mark before releasing the shoal at the point of capture. We recaptured tagged fishes in the study area on five subsequent days, noting their identity, their location and the individuals with which they were associated. Stable partner associations between fishes were observed which might provide the basis for shoal fidelity via social networks. These results suggest the potential for the kinds of inter-individual association patterns assumed by models of predator inspection and 'tit-for-tat' behaviours in free-ranging fishes. PMID:12495488

Ward, Ashley J W; Botham, Marc S; Hoare, Daniel J; James, Richard; Broom, Mark; Godin, Jean-Guy J; Krause, Jens

2002-01-01

143

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

PubMed

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

Bukaciński; Bukacińska; Lubjuhn

2000-02-01

144

Behavioural responses to human intruders of herring gulls (Larus Argentatus ) and great black-backed gulls (L. Marinus ) with varying exposure to human disturbance.  

PubMed

This study examined differences in response to humans approaching the nest for incubating herring and great black-backed gulls with varying amounts of prior exposure to humans. Gulls nesting in frequently disturbed areas sat more tenaciously, responded more slowly, and returned to the nest more quickly following the intruder's retreat, than birds nesting in less disturbed areas. The species differed in their responses in different areas. Stage of incubation had little effect, except that late in incubation herring gulls returned to the nest more quickly. Weather variables affected responses of great black-backed gulls. For both species the behaviours we scored when the experimenter approached the nest were correlated, as were those following departure, but there was no correlation between these two sets of responses. Our study provides evidence on the relationships among components of an alarm and escape response, and provides a measure of influence of human disturbance for two species of gulls. PMID:24897679

Burger, J; Gochfeld, M

1983-10-01

145

DNA fingerprinting reveals elevated mutation rates in herring gulls inhabiting a genotoxically contaminated site  

SciTech Connect

The authors used multi-locus DNA fingerprinting to examine families of herring gulls (Larus argentatus) from a genotoxically contaminated site (Hamilton Harbour) and from a pristine location (Kent Island, Bay of Fundy) to show significant differences in mutation rates between the locations. Overall the authors identified 17 mutant bands from 15 individuals of the 35 examined from Hamilton Harbour, and 7 mutant fragments from 7 individuals, of the 43 examined from Kent Island; a mutation frequency of 0.429 per nestling for Hamilton Harbour and 0.163 for Kent Island. The total number of individuals with mutant bands was significantly higher at Hamilton Harbour than at Kent Island (X{sup 2}=6.734; df = 1; P < 0.01). Ongoing analysis of other less contaminated sites also reveals lower mutation rates than those seen in Hamilton Harbour. With multi-locus DNA fingerprinting many regions of the genome can be surveyed simultaneously. The tandemly repeated arrays of nucleotides examined with DNA fingerprinting are known to have elevated rates of mutation. Furthermore, the mutations seen with DNA fingerprinting are predominantly heritable. Other biomarkers currently used in situ are not able to monitor direct and heritable DNA mutation, or measure biological endpoints that frequently result in spontaneous abortion creating difficulty in observing significantly elevated levels in viable offspring. The authors suggest that multilocus DNA fingerprinting can be used as a biomarker to identify potentially heritable risks before the onset of other types of ecological damage. This approach provides a direct measure of mutation in situ and in vivo in a vertebrate species under ambient conditions.

Yauk, C.L.; Quinn, J.S. [McMaster Univ., Hamilton, Ontario (Canada). Dept. of Biology

1995-12-31

146

Aryl hydrocarbon receptor agonists in European herring gull (Larus argentatus) eggs from Norway.  

PubMed

Herring gull eggs from two locations in Norway, an island situated in the north (Musvær, 69.88° N, 18.55° E) and an island in the southeast (Reiaren, 59.15° N, 10.46° E) of the country, were analyzed for the presence of aryl hydrocarbon receptor (AhR) agonists. AhR agonist activity was determined using the dioxin-responsive chemically activated luciferase expression (DR-CALUX) assay to calculate the toxic equivalent quotient (TEQ)CALUX. TEQCALUX ranged from 16 to 401 pg TEQ/g lipid in the samples from the north (n = 11) and between 6 and 360 pg TEQ/g lipid (n = 12) in the southeastern samples. The large variance between the individual samples is postulated to be due to different feeding habits of individual birds. The levels of AhR agonists detected might lead to adverse effects for the developing embryo or to a significant increase of contaminant load for human consumers of eggs. PMID:24754391

Muusse, Martine; Christensen, Guttorm; Langford, Katherine; Tollefsen, Knut-Erik; Thomas, Kevin V

2014-01-01

147

Effects of invasive European fire ants (Myrmica rubra) on herring gull (Larus argentatus) reproduction.  

PubMed

Various invasive ant species have negatively affected reproductive success in birds by disrupting nest site selection, incubation patterns, food supply, and by direct predation on nestlings. Impacts can be particularly severe when non-native ants colonize seabird nesting islands where thousands of birds may nest in high densities on the ground or in burrows or crevices. Here we report on the first documented effects of Myrmica rubra, the European fire ant, on the reproduction of birds in its non-native range. We documented herring gulls (Larus argentatus) on Appledore Island, Maine, engaging in more erratic incubation behaviors at nests infested by the ants. Newly-hatched chicks in some nests were swarmed by ants, leading to rapid chick death. Due to high overall rates of chick mortality, survival probabilities did not vary between nests with and without ant activity, however chick growth rates were slower at nests with ants than at ant-free nests. Ant infestation likely leads to longer-term fitness consequences because slower growth rates early in life may ultimately lead to lower post-fledging survival probabilities. PMID:23691168

DeFisher, Luke E; Bonter, David N

2013-01-01

148

Antigenic and genetic characterization of a novel hemagglutinin subtype of influenza A viruses from gulls.  

PubMed Central

Influenza A virus isolates from ring-billed, Franklin, blackback, and herring gulls in the United States possess a hemagglutinin (HA) distinct from the 12 reference HA subtypes. Serological assays (hemagglutination inhibition and double-immunodiffusion) with specific antisera to reference strains and to a representative gull isolate showed that the HA of the gull virus was not antigenically related to that of any known subtype. The gull virus did not replicate in ducks or chickens but did replicate in ferrets. Comparison of the nucleotide sequences (and deduced amino acid sequences) of the 3' 20% of the HA genes of these viruses indicates that the gull viruses represent a genetically distinct group. We propose that this HA, which has been detected only in gull isolates thus far, be called the H13 subtype. PMID:7097861

Hinshaw, V S; Air, G M; Gibbs, A J; Graves, L; Prescott, B; Karunakaran, D

1982-01-01

149

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

Microsoft Academic Search

:   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

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

2001-01-01

150

[Seasonal dynamics of the trematodes fauna in herring gull (Larus argentatus Pontopp.) of Kola Bay].  

PubMed

Trematode fauna of the herring gulls from Kola Bay (Barents Sea) was investigated in March, May, June, and September 2005. The data on the trematode species composition and indices of the invasion of gulls with trematodes are given for each season. It was established, that trematode species composition is increased from spring to summer, and intensity of the gulls' invasion with some trematode species is increased from summer to autumn. Ecological factors causing seasonal differences of the trematode fauna in gulls are discussed. PMID:21061591

Kuklin, V V; Kuklina, M M; Kisova, N E

2010-01-01

151

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

PubMed

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

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

2012-01-01

152

Maturation of shoaling behavior is accompanied by changes in the dopaminergic and serotoninergic systems in zebrafish  

PubMed Central

The zebrafish has been one of the preferred vertebrate model organisms of developmental biology, and is becoming an important research tool for behavioral neuroscience and behavior genetics. A prominent feature of zebrafish is their strong shoaling tendency. Most recently, the first paper investigating the development of shoaling in zebrafish demonstrated that a few days after hatching zebrafish do not shoal, but that shoaling tendency gradually increases during development. The current paper investigates this phenomenon using the nearest neighbor distance, a measure most frequently employed for the quantification of shoal cohesion in fish. We demonstrate that shoal cohesion increases with age, while thigmotaxis, “wall hugging”, does not show a consistent age-dependent change. The mechanisms underlying the maturation of shoaling are unknown. HPLC analysis of whole brain extracts finds the concentration of dopamine, DOPAC, serotonin, and 5-HIAA normalized to total brain protein weight to increase with age. Although the behavioral and neurochemical results are only correlative at this point, they may open a new avenue into the investigation of the mechanisms and development of social behavior in zebrafish. PMID:21656763

Buske, Christine; Gerlai, Robert

2011-01-01

153

Use of a nesting platform by Gull-billed Terns and Black Skimmers at the Salton Sea, California  

USGS Publications Warehouse

In 2006, we constructed an elevated nesting platform at the Salton Sea, California, and monitored its use by Gull-billed Terns and Black Skimmers over three subsequent breeding seasons. Black Skimmers were the first to colonize the platform with a total of five nests in 2006. In 2007 Gull-billed Terns colonized the platform with a total of 28 nests and the number of Black Skimmer nests increased to 20. Neither species nested on the platform in 2008. Low success for both species was probably influenced by at least two factors. First, when both species nested on the platform, nest densities were higher than is typical of their colonies on larger, earthen islands, and colony success may have been reduced by overcrowding. Second, lack of access to water may have reduced chicks' ability to thermoregulate effectively in the hot environment of the Salton Sea. Refinements to the size, design, and location of artificial nesting habitats are necessary to enhance productivity of colonial groundnesting birds at the Salton Sea successfully.

Molina, K.C.; Ricca, M.A.; Miles, A.K.; Schoneman, C.

2009-01-01

154

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

PubMed

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

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

2014-12-01

155

Surficial geology of the sea floor in Long Island Sound offshore of Plum Island, New York  

USGS Publications Warehouse

The U.S. Geological Survey (USGS), the Connecticut Department of Environmental Protection, and the National Oceanic and Atmospheric Administration (NOAA) have been working cooperatively to interpret surficial sea-floor geology along the coast of the Northeastern United States. NOAA survey H11445 in eastern Long Island Sound, offshore of Plum Island, New York, covers an area of about 12 square kilometers. Multibeam bathymetry and sidescan-sonar imagery from the survey, as well as sediment and photographic data from 13 stations occupied during a USGS verification cruise are used to delineate sea-floor features and characterize the environment. Bathymetry gradually deepens offshore to over 100 meters in a depression in the northwest part of the study area and reaches 60 meters in Plum Gut, a channel between Plum Island and Orient Point. Sand waves are present on a shoal north of Plum Island and in several smaller areas around the basin. Sand-wave asymmetry indicates that counter-clockwise net sediment transport maintains the shoal. Sand is prevalent where there is low backscatter in the sidescan-sonar imagery. Gravel and boulder areas are submerged lag deposits produced from the Harbor Hill-Orient Point-Fishers Island moraine segment and are found adjacent to the shorelines and just north of Plum Island, where high backscatter is present in the sidescan-sonar imagery.

McMullen, K.Y.; Poppe, L.J.; Danforth, W.W.; Blackwood, D.S.; Schaer, J.D.; Ostapenko, A.J.; Glomb, K.A.; Doran, E.F.

2010-01-01

156

Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447  

SciTech Connect

This report presents the 2007 groundwater monitoring results collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) at the Project Shoal Area (PSA) 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 (DOE-EM) to DOE-LM on October 1, 2006. Requirements for CAU 447, as specified in the Federal Facility Agreement and Consent Order (FFACO 2005) entered into by DOE, the U.S. Department of Defense (DOD), and the State of Nevada, includes groundwater monitoring in support of site closure. This is the first groundwater monitoring report prepared by DOE-LM for the PSA.

None

2008-01-01

157

Sleeping gulls monitor the vigilance behaviour of their neighbours  

PubMed Central

Individuals in groups are often thought to scan their surroundings for threats independently of one another. Models, however, suggest that foragers should monitor the vigilance level of their neighbours to prevent cheating, and to gather information about incipient predation risk. Evidence for monitoring of vigilance is scant. Here, I examined changes in vigilance levels in sleeping gulls (Larus sp.) surrounded by neighbours in various states of alertness. Controlling for group size and neighbour density, gulls interrupted sleep more often to scan their surroundings, and were therefore more vigilant, when their neighbours were alert rather than sleeping or preening. The results provide evidence for copying of vigilance within groups of birds, suggesting a complex flow of information about predation risk in groups. PMID:18940772

Beauchamp, Guy

2008-01-01

158

Sediment Delivery to Diamond Shoals: a Field Experiment at Cape Hatteras Point, North Carolina (Invited)  

NASA Astrophysics Data System (ADS)

Diamond Shoals is a complex of sand shoals extending more than 20 km seaward from Cape Hatteras Point, North Carolina. We conducted a one-month field experiment at Cape Hatteras Point during February 2010, with a primary objective of quantifying the processes that deliver sediment to Diamond Shoals. A leading hypothesis from previous literature, mainly focused on the similar Cape Lookout Shoals, is that wave-driven nearshore currents on the coasts flanking the cape deliver sand to the proximal (near coast) part of the shoal, and flows with the potential to return sand to one of the flanking shorelines have less capacity. The shoal is hypothesized to be a long-term sediment sink because of this transport asymmetry. We deployed wave- and current-measuring instruments in the nearshore and installed several types of remote sensing devices around Cape Hatteras Point. Remote sensing devices included a video camera mounted on the Cape Hatteras lighthouse to measure nearshore surface currents and a VHF (48MHz) WERA (WEllen RAdar) station for measuring wide-area (O: 10 km) surface currents over Diamond Shoals. Ground-based lidar topography, wide-area wave dissipation intensity, wave direction, and bathymetry were measured by the CLARIS (Coastal Lidar And Radar Imaging System) and LARC (Lighter Amphibious Resupply Cargo) surveying systems. A shoreline change analysis is used to quantify the cape’s recent morphologic evolution and previous geophysical surveys provide information on the shoal’s thickness and geologic framework. Wind and wave directions during the experiment were similar to the long-term climatology, with principal components from the north/northeast and west/southwest. Results from the nearshore instrumentation show that north/northeast conditions force mean currents from the north side of the cape toward the shoal and west/southwest conditions force currents from the south side of the cape toward the shoal. The very shallow water over Diamond Shoals (in places less than 1 m at low tide) effectively blocks waves and currents from entering the leeward side of the shoal and thus there is no reversal of flow direction (from the shoal towards the flanking coast) on the sheltered side of the cape. During a short period when the wave direction was from the east, flows were directed from the shoal towards both flanking shorelines; however, this condition is much less common in the long-term climatology than north/northeast and west/southwest conditions. If sand transport direction is assumed to follow the mean current direction, these observations support the hypothesis of long-term net sand deposition in Diamond Shoals derived from the cape’s flanking coasts. These results will be combined with remote sensing and other data to furnish a wider-field examination of potential shoal-building processes.

List, J. H.; Warner, J. C.; Thieler, E. R.; Haas, K. A.; Voulgaris, G.; McNinch, J. E.; Brodie, K. L.

2010-12-01

159

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

PubMed

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

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

2012-09-01

160

Is asynchronous hatching adaptive in herring gulls ( Larus argentatus )?  

Microsoft Academic Search

Hatching asynchrony commonly induces a size hierarchy among siblings and the resultant competition for food between siblings\\u000a can often lead to starvation of the smallest chicks within a brood. We created herring gull (Larus argentatus) broods with varying degrees of hatching synchrony by manipulating the timing of incubation while maintaining the originally\\u000a laid eggs. The degree of hatching asynchrony affected

Lars Hillström; Mikael Kilpi; Kai Lindström

2000-01-01

161

Immune function and organochlorine pollutants in Arctic breeding glaucous gulls.  

PubMed

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

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

2004-11-01

162

Methyl anthranilate formulations repel gulls and mallards from water  

Microsoft Academic Search

Two formulations of methyl anthranilate (MA), one (ReJex-iT™ TP-40 [TP-40]) containing a surfactant, the other (ReJex-iT™ AP-50 [AP-50]) a miscible, free-flowing powder, effectively repelled captive mallards (Anas platyrhynchos) from pools of water in pen tests, and\\/or free-ranging gulls (Larus delawarensis and L. argentatus) from pools of water in field trials for 4–11 days. With one exception, pool entries and bill

Jerrold L. Belant; Steven W. Gabrey; Richard A. Dolbeer; Thomas W. Seamans

1995-01-01

163

Nocturnal behavior of gulls in coastal New Jersey  

Microsoft Academic Search

We studied the behavior of gulls at night with an image intensifier telescope to determine whether they were active at night,\\u000a and the extent of their foraging in coastal habitats of New Jersey in the summer, fall, and winter of 1989–1990. Regression\\u000a models and Kruskal-Wallis tests indicated that date, time of day, tide, cloud cover, moon phase, and study location

Joanna Burger; Kevin J. Staine

1993-01-01

164

Estimate of removal rate of Nereis virens (Polychaeta: Nereidae) from an intertidal mudflat by gulls ( Larus spp.)  

Microsoft Academic Search

The feeding behavior of herring gulls (Larus argentatus), ringed-billed gulls (L. delawarensis) and great blackbacked gulls (L. marinus) on an intertidal mudflat in Maine, USA, was investigated. Remains of fish, mussels, crabs, insects, and the polychaeteNereis virens were recovered from gull feces. Forty-three percent of the fecal samples containedN. virens jaws, setae, or both. A comparison of jaws from fecal

W. G. Ambrose

1986-01-01

165

Ionic alkylleads in herring gulls from the Great Lakes region  

SciTech Connect

Herring gull (Larus argentatus) tissues, collected from various breeding colonies in the Great Lakes, were examined to determine alkyllead levels and possible alkyllead sources into the Great Lakes region. Ionic trialkyl- and dialkyllead species (R/sub 3/Pb/sup +/, R/sub 2/Pb/sup 2 +/; R = Me, Et) were quantitated by gas chromatography-atomic absorption spectrometry. The extraction procedure was tested at trace levels (3-4 ppb as Pb) with four domestic chicken (Gallus domesticus) tissues. Trimethyllead was found in two avian species and all examined tissues. Methyllead levels frequently exceeded ethyllead levels with no direct automotive source. Correlation between alkyllead levels in herring gull tissue and lake sediment lead levels suggests possible methylation but not ethylation of inorganic lead. The methyllead concentration trend in gull tissues. Lake Ontario > Lake Huron approx. = Lake Erie > Lake Superior, was opposite to the ethyllead concentration trend, Lake Superior > Lake Huron > Lake Erie approx. = Lake Ontario. 40 references, 3 figures, 7 tables.

Forsyth, D.S.; Marshall, W.D.

1986-10-01

166

Genotoxicity in herring gulls (Larus argentatus) in Sweden and Iceland.  

PubMed

Adult and young herring gulls (Larus argentatus) in Sweden and Iceland were investigated with respect to DNA adducts, analysed with the nuclease-P1 version of the (32)P-postlabelling method, and micronucleated erythrocytes. Three important aims were: (1) to estimate the degree of exposure to genotoxic environmental pollutants in the Baltic Sea area and Iceland, (2) to evaluate the utility of the investigated biomarkers in birds, and (3) to investigate if there was any relationship between genotoxic effects and thiamine deficiency. The results demonstrate that both Swedish and Icelandic herring gulls are exposed to genotoxic pollution. Urban specimens have higher levels of DNA adducts than rural specimens, but background exposure to genotoxic environmental pollutants, such as PAHs, is also significant. In the herring gull the general level of DNA adducts in the liver seems to be higher than in fish. DNA adducts were most abundant in the liver, followed by the kidney, intestinal mucosa, and whole blood, in decreasing order. The frequency of micronucleated erythrocytes was probably slightly elevated in all the investigated sites, reflecting a significant background exposure. The level of DNA adducts was unrelated to the frequency of micronucleated erythrocytes, and both these variables were unrelated to symptoms of thiamine deficiency. The investigation confirmed the utility of DNA adducts, and probably also micronucleated erythrocytes, as biomarkers of genotoxicity in birds. PMID:20643223

Skarphedinsdottir, Halldora; Hallgrimsson, Gunnar Thor; Hansson, Tomas; Hägerroth, Per-Ake; Liewenborg, Birgitta; Tjärnlund, Ulla; Akerman, Gun; Barsiene, Janina; Balk, Lennart

2010-09-30

167

[The reaction of the bursa and thymus eosinophils in the herring gull after the experimental infection with gull-tapeworm].  

PubMed

Using the methods of light microscopy, eosinophil topography, quantitative and qualitative changes (degranulation level of and a cationic protein content) were studied in the thymus and bursa of 36 herring gull nestlings Larus argentatus mongolicus (Suskin, 1925) 2 weeks after experimental infestation with gull-tapeworm Diphyllobothrium dendriticum (Nitsch, 1824). Eosinophils in the thymus were located in trabecules, mainly close to the blood vessels, thymic (Hassall's) corpuscles and also directly inside them, while in the bursa they were found within the internodular space. As compared with the control bird counts, relative eosinophil count in the birds with an average invasion intensity was increased 3.8 times in the thymus and 2.5 times in the bursa. In birds with high invasion intensity, these counts were increased 4 times in the thymus and 1.2 times in the bursa. PMID:21500430

Fomina, A S; Pronina, S V

2010-01-01

168

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

E-print Network

in herring gulls (Larus argentatus) (Gold- spink et al., '78) andAmerican kestrels (Falco sparverius) (Meyers 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

Meyers, Ron

169

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

Microsoft Academic Search

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

M Hario; K Himberg; T Hollmén; E Rudbäck

2000-01-01

170

75 FR 29574 - Final Legislative Environmental Impact Statement for the Harvest of Glaucous-Winged Gull Eggs by...  

Federal Register 2010, 2011, 2012, 2013, 2014

...for the Harvest of Glaucous-Winged Gull Eggs by the Huna Tlingit in Glacier Bay National...for the Harvest of Glaucous-Winged Gull Eggs by the Huna Tlingit in Glacier Bay National...for the harvest of glaucous-winged gull eggs by the Huna Tlingit in Glacier Bay...

2010-05-26

171

Comparison of gull-specific assays targeting 16S rRNA gene of Catellicoccus marimammalium and Streptococcus spp.  

EPA Science Inventory

Gulls have been implicated as a source of fecal contamination in inland and coastal waters. Only one gull-specific assay is currently available (i.e., gull2 qPCR assay). This assay is based on the 16S rRNA gene of Catellicocclls marimammalium and has showed a high level of host-s...

172

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

PubMed

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

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

1977-01-01

173

Introgressive hybridization and the evolutionary history of the herring gull complex revealed by mitochondrial and nuclear DNA  

Microsoft Academic Search

BACKGROUND: Based on extensive mitochondrial DNA (mtDNA) sequence data, we previously showed that the model of speciation among species of herring gull (Larus argentatus) complex was not that of a ring species, but most likely due more complex speciation scenario's. We also found that two species, herring gull and glaucous gull (L. hyperboreus) displayed an unexpected biphyletic distribution of their

Viviane Sternkopf; Dorit Liebers-Helbig; Markus S Ritz; Jun Zhang; Andreas J Helbig; Peter de Knijff

2010-01-01

174

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

Microsoft Academic Search

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

LEE KWOK SHING; BOSCO PUI LOK

2007-01-01

175

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

E-print Network

either through a UV-transmitting [UV(C)] or a UV-blocking [UV(K)] filter. Test fish preferred to join environment, suggesting a potential trade-off between UV radiation and lower brightness during shoal choice

176

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

PubMed

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

Vigfúsdóttir, Freydís; Pálsson, Snaebjörn; Ingólfsson, Agnar

2008-09-12

177

What`s normal?: Body condition in Great Lakes herring gulls  

SciTech Connect

The Canadian Wildlife Service`s herring gull (Larus argentatus) surveillance program has demonstrated the usefulness of this species as a monitor of spatial and temporal trends in contaminant levels. However, the effects of environmental contaminants on gulls are difficult to distinguish from the effects of other anthropogenic stressors such as the introduction of exotic species, overfishing and habitat loss. To understand the relative importance of these factors in regulating the success of individual gulls and, hence, gull populations, the authors must first have a better understanding of what constitutes a ``normal`` bird. Improving the ability to differentiate between normal and abnormal birds is crucial in any health assessment of Great Lakes gulls. Body condition has been shown to be an important measure of a bird`s ability to provide energy for egg production, migration etc. Numerous approaches have been used to assess condition, most of which required that the bird be sacrificed. In this study, the authors describe a nonlethal technique to quantify body condition in herring gulls. Multivariate statistics are used to quantify body size, relate body size to total mass and from that, determine relative body condition. Initially, body condition is assessed in gulls from a reference colony where reproductive success is normal and anthropogenic influences are limited. This reference population is then used as a baseline against which other gull populations are compared.

Hebert, C.E.; Shutt, J.L. [Canadian Wildlife Service, Hull, Quebec (Canada)

1994-12-31

178

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

Microsoft Academic Search

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

J. Parsons

1970-01-01

179

Mercury levels in Great Lakes herring gull ( Larus argentatus) eggs, 1972–1992  

Microsoft Academic Search

Since 1971, the herring gull (Larus argentatus) has been used as a sentinel species for monitoring the levels of persistent contaminants in the Great Lakes ecosystem. In this study, 21 herring gull colonies in the Great Lakes and connecting channels were sampled during 1972–1976, 1981–1983, 1985 and 1992. For each year, 10 eggs (usually) were collected from each colony site

M. D. Koster; D. P. Ryckman; D. V. C. Weseloh; J. Struger

1996-01-01

180

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

Microsoft Academic Search

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

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

2006-01-01

181

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...

182

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

Microsoft Academic Search

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

MARCELO BERTELLOTTI; PABLO YORIO; MARICEL GIACCARDI

183

BREEDING AND ANNUAL CYCLE OF LAUGHING GULLS IN TAMPA BAY, FLORIDA  

Microsoft Academic Search

The Laughing Gull (Larus atric&) is one of the most familiar species of the coasts of the eastern United States. Although the behavior of this gull has been intensively studied (e.g. Beer, 1970a, 1970b; Impekoven, 1973)) many aspects of the breeding biology are little or poorly known. Our study was designed to gather data on reproduction in this species in

JAMES J. DINSMORE; RALPH W. SCHREIBER

184

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

Federal Register 2010, 2011, 2012, 2013, 2014

...APHIS-2006-0035] Gull Hazard Reduction Program at John F. Kennedy International Airport; Record...the Gull Hazard Reduction Program at John F. Kennedy International Airport. DATES...populations and land uses in and around the John F. Kennedy International Airport. This...

2012-07-26

185

Novel methods for discriminating behavioral differences between stickleback individuals and populations in a laboratory shoaling assay  

PubMed Central

Threespine sticklebacks (Gasterosteus aculeatus) from different habitats have been observed to differ in shoaling behavior, both in the wild and in laboratory studies. In the present study, we surveyed the shoaling behavior of sticklebacks from a variety of marine, lake, and stream habitats throughout the Pacific Northwest. We tested the shoaling tendencies of 113 wild-caught sticklebacks from 13 populations using a laboratory assay that was based on other published shoaling assays in sticklebacks. Using traditional behavioral measures for this assay, such as time spent shoaling and mean position in the tank, we were unable to find population differences in shoaling behavior. However, simple plotting techniques revealed differences in spatial distributions during the assay. When we collapsed individual trials into population-level data sets and applied information theoretic measurements, we found significant behavioral differences between populations. For example, entropy estimates confirm that populations display differences in the extent of clustering at various tank positions. Using log-likelihood analysis, we show that these population-level observations reflect consistent differences in individual behavioral patterns that can be difficult to discriminate using standard measures. The analytical techniques we describe may help improve the detection of potential behavioral differences between fish groups in future studies. PMID:21804684

Wark, Abigail R.; Wark, Barry J.; Lageson, Tessa J.

2011-01-01

186

Molecular and epidemiological characterization of avian influenza viruses from gulls and dabbling ducks in Norway  

PubMed Central

Background Wild aquatic birds constitute the natural reservoir for avian influenza viruses (AIVs). Separate Eurasian and American AIV gene pools exist. Here, the prevalence and diversity of AIVs in gulls and dabbling ducks in Norway were described. The influence of host species and temporal changes on AIV prevalence was examined. Five AIVs from Norway, including three from common gull (Larus canus), were analyzed along with 10 available AIV genomes from gulls in Eurasia to search for evidence of intracontinental and intercontinental reassortment of gene segments encoding the internal viral proteins. Methods Swabs collected from 2417 dabbling ducks and gulls in the south-west of Norway during five ordinary hunting seasons (August-December) in the period 2005–2010 were analyzed for presence of AIV. Multivariate linear regression was used to identify associations between AIV prevalence, host species and sampling time. Five AIVs from mallard (Anas platyrhynchos) (H3N8, H9N2) and common gull (H6N8, H13N2, H16N3) were full-length characterized and phylogenetically analyzed together with GenBank reference sequences. Results Low pathogenic AIVs were detected in 15.5% (CI: 14.1–17.0) of the samples. The overall AIV prevalence was lower in December compared to that found in August to November (p = 0.003). AIV was detected in 18.7% (CI: 16.8–20.6) of the dabbling ducks. A high AIV prevalence of 7.8% (CI; 5.9–10.0) was found in gulls. A similar temporal pattern in AIV prevalence was found in both bird groups. Thirteen hemagglutinin and eight neuraminidase subtypes were detected. No evidence of intercontinental reassortment was found. Eurasian avian (non H13 and H16) PB2 or PA genes were identified in five reference Eurasian gull (H13 and H16) AIV genomes from GenBank. The NA gene from the Norwegian H13N2 gull isolate was of Eurasian avian origin. Conclusions The similar temporal pattern in AIV prevalence found in dabbling ducks and gulls, the relatively high virus prevalence detected in gulls and the evidence of intracontinental reassortment in AIVs from gulls indicate that gulls that interact with dabbling ducks are likely to be mixing vessels for AIVs from waterfowl and gulls. Our results support that intercontinental reassortment is rare in AIVs from gulls in Eurasia. PMID:23575317

2013-01-01

187

Validation Analysis of the Shoal Groundwater Flow and Transport Model  

SciTech Connect

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

A. Hassan; J. Chapman

2008-11-01

188

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

Microsoft Academic Search

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

Turid Vikoren; Gudbrand Stuve

189

Factors controlling navigation-channel Shoaling in Laguna Madre, Texas  

USGS Publications Warehouse

Shoaling in the Gulf Intracoastal Waterway of Laguna Madre, Tex., is caused primarily by recycling of dredged sediments. Sediment recycling, which is controlled by water depth and location with respect to the predominant wind-driven currents, is minimal where dredged material is placed on tidal flats that are either flooded infrequently or where the water is extremely shallow. In contrast, nearly all of the dredged material placed in open water >1.5 m deep is reworked and either transported back into the channel or dispersed into the surrounding lagoon. A sediment flux analysis incorporating geotechnical properties demonstrated that erosion and not postemplacement compaction caused most sediment losses from the placement areas. Comparing sediment properties in the placement areas and natural lagoon indicated that the remaining dredged material is mostly a residual of initial channel construction. Experimental containment designs (shallow subaqueous mound, submerged levee, and emergent levee) constructed in high-maintenance areas to reduce reworking did not retain large volumes of dredged material. The emergent levee provided the greatest retention potential approximately 2 years after construction.

Morton, R.A.; Nava, R.C.; Arhelger, M.

2001-01-01

190

Molecular characterization of novel circoviruses from finch and gull.  

PubMed

The purpose of this study was to molecularly characterize circoviruses that infect finches and gulls. Circovirus-specific DNAs were isolated using polymerase chain reaction methods from bursa of Fabricius tissues from a Gouldian finch (Chloebia gouldiae) and a herring gull (Larus argentatus) that were known to be circovirus-infected. Nucleotide sequence determination and analysis of cloned genomic DNAs showed that these circoviruses represented novel members of the genus Circovirus of the family Circoviridae, and have been tentatively named Finch circovirus (FiCV) and Gull Circovirus (GuCV). Both new circoviruses shared genome organizational features with previously characterized circoviruses, such that both contained two major, inversely-arranged open reading frames encoding the putative replication-associated and capsid proteins, and both contained a potential stem-loop and nonanucleotide motif. Phylogenetic analyses based on genome nucleotide sequences and involving the seven additional genus members indicated that FiCV and GuCV were more closely related to canary circovirus, beak and feather disease virus and pigeon circovirus, and that FiCV and canary circovirus were the most closely related avian circoviruses. Pairwise comparisons showed that the capsid proteins of FiCV and GuCV shared highest amino acid identity values with those of canary circovirus (62.0%) and pigeon circovirus (40.6%), respectively. The 5' intergenic region of GuCV was longer (207 nucleotides) and contained more direct and inverse repeated sequences than those of other circoviruses, while the 3' intergenic region of FiCV was notable in being longer (307 nucleotides) than its counterparts in other circoviruses and in containing two long repeats of 77 nucleotides. PMID:17364513

Todd, D; Scott, A N J; Fringuelli, E; Shivraprasad, H L; Gavier-Widen, D; Smyth, J A

2007-02-01

191

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

USGS Publications Warehouse

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.

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

2006-01-01

192

Herring gull eggs indicate stabilizing Great Lakes PCB concentrations  

SciTech Connect

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.

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

1995-12-31

193

Insects, vegetation, and the control of laughing gulls (Larus atricilla) at Kennedy International Airport, New York  

USGS Publications Warehouse

1. In response to a purported 'bird-strike problem' at J.F. Kennedy International Airport in New York City, we examined short (5 cm) and long (45 cm) grass heights as gull deterrents, in a randomized-block experiment. 2. Vegetative cover, numbers of adult insects and of larval beetles (suspected on-airport food of the gulls) were sampled in the six-block, 36-plot study area, as well as gut contents of adult and downy young gulls in the immediately adjacent colony in the Jamaica Bay Wildlife Refuge. 3. We found that (i) Oriental beetle larvae were the most numerous and concentrated in one experimental block; (ii) beetle larvae numbers were uncorrelated with grass height; (iii) adult beetles were also uncorrelated with grass height; (iv) laughing gulls were distributed across blocks irrespective of percentage cover; (v) within blocks, laughing gulls were selecting short grass and avoiding long grass plots; (vi) laughing gull numbers were positively associated with numbers of Oriental beetle larvae; (vii) adult laughing gulls on the airport were eating lower-nutrition food of terrestrial origin (74-83% adult beetles, mostly Oriental plus green June and ground beetles); (viii) on the other hand, gull chicks in the adjacent breeding colony were being fed more easily digested, higher-protein food of marine origin (86-88% fishes, crustacea and molluscs); (ix) laughing gulls on the airport were taking their adult beetles only in short-grass plots, ignoring large numbers in adjacent long grass; (x) during the summer, on-airport gulls shifted from performing largely maintenance activities on pavement to feeding actively for beetles on newly mown short grass, the change coinciding with adult beetle emergence; (xi) standing water on the airport attracted significantly more gulls than dry areas all summer long. 4. We recommend a series of ecologically compatible, but aggressive habitat management actions for controlling laughing gulls on Kennedy Airport by rendering the airport unattractive to them, notably by implementing an airport-wide programme of long-grass encouragement, draining standing water and improving runoff in water-collecting areas, and controlling beetles. 5. We conclude by outlining the necessity for airport-wide bird, vegetation and habitat management programmes fully integrated into airport operation and planning activities.

Buckley, P.A.; McCarthy, M.

1994-01-01

194

The incidence and significance of salmonella carriage by gulls (Larus spp.) in Scotland.  

PubMed Central

Salmonella carriage in 5888 gulls sampled by cloacal lavage was found to be 7.8%. Marked geographical and seasonal differences in carriage rates were found. These differences appeared to be associated with human population density and seasonal differences in the reported incidence of human salmonellosis. The maximum duration of salmonella excretion in 17 laboratory-maintained gulls was 4 days and the number of salmonellae excreted was never more than 170 per gram of faeces. On the basis of this study it is suggested that gulls are not important factors in the aetiology of human salmonellosis. PMID:4067287

Girdwood, R. W.; Fricker, C. R.; Munro, D.; Shedden, C. B.; Monaghan, P.

1985-01-01

195

Prevalence of Salmonella spp., Campylobacter spp. and Listeria spp. in ring-billed gulls (Larus delawarensis).  

PubMed

Cloacal swabs collected from 264 ring-billed gulls (Larus delawarensis) at four sites near Montréal, Canada were cultured for the presence of Salmonella spp., Campylobacter spp. and Listeria spp. All birds were apparently healthy when captured or killed. Of all birds examined, 8.7%, 15.9% and 9.5%, respectively, were infected with Salmonella spp., Campylobacter spp. and Listeria monocytogenes. Overall, 29.9% of gulls sampled harbored one or more of these bacteria. Gulls probably play only a minor role in the epizootiology of these bacteria. PMID:1474648

Quessy, S; Messier, S

1992-10-01

196

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

USGS Publications Warehouse

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.

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

197

Microsatellites identify depredated waterfowl remains from glaucous gull stomachs  

USGS Publications Warehouse

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.

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

1998-01-01

198

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

PubMed

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

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

2010-06-01

199

46 CFR 401.407 - Basic rates and charges on Lake Erie and the navigable waters from Southeast Shoal to Port Huron...  

Code of Federal Regulations, 2014 CFR

...Lake Erie and the navigable waters from Southeast Shoal to Port...a) Area 4 (Undesignated Waters): Service Lake Erie (East of Southeast Shoal) Buffalo 6-hour Period $849... (b) Area 5 (Designated Waters): Any point on or in...

2014-10-01

200

46 CFR 401.407 - Basic rates and charges on Lake Erie and the navigable waters from Southeast Shoal to Port Huron...  

Code of Federal Regulations, 2012 CFR

...Lake Erie and the navigable waters from Southeast Shoal to Port...a) Area 4 (Undesignated Waters): Service Lake Erie (East of Southeast Shoal) Buffalo Six-hour Period $760... (b) Area 5 (Designated Waters): Any point on or in...

2012-10-01

201

46 CFR 401.407 - Basic rates and charges on Lake Erie and the navigable waters from Southeast Shoal to Port Huron...  

Code of Federal Regulations, 2010 CFR

...Erie and the navigable waters from Southeast Shoal to...Area 4 (Undesignated Waters): Service Lake Erie (East ofSoutheast Shoal) Buffalo Six-Hour Period ...b) Area 5 (Designated Waters): Any point on or...

2010-10-01

202

46 CFR 401.407 - Basic rates and charges on Lake Erie and the navigable waters from Southeast Shoal to Port Huron...  

Code of Federal Regulations, 2011 CFR

...Lake Erie and the navigable waters from Southeast Shoal to Port...a) Area 4 (Undesignated Waters): Service Lake Erie (East of Southeast Shoal) Buffalo Six-hour period $791... (b) Area 5 (Designated Waters): Any point on or in...

2011-10-01

203

46 CFR 401.407 - Basic rates and charges on Lake Erie and the navigable waters from Southeast Shoal to Port Huron...  

Code of Federal Regulations, 2013 CFR

...Lake Erie and the navigable waters from Southeast Shoal to Port...a) Area 4 (Undesignated Waters): Service Lake Erie (East of Southeast Shoal) Buffalo 6-Hour Period $828... (b) Area 5 (Designated Waters): Any point on or in...

2013-10-01

204

Circulation of a Meaban-like virus in yellow-legged gulls and seabird ticks in the western Mediterranean basin.  

PubMed

In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis), a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus), were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring the spatial and temporal distribution of this flavivirus as well as its potential pathogenicity for animals and humans. PMID:24625959

Arnal, Audrey; Gómez-Díaz, Elena; Cerdà-Cuéllar, Marta; Lecollinet, Sylvie; Pearce-Duvet, Jessica; Busquets, Núria; García-Bocanegra, Ignacio; Pagès, Nonito; Vittecoq, Marion; Hammouda, Abdessalem; Samraoui, Boudjéma; Garnier, Romain; Ramos, Raül; Selmi, Slaheddine; González-Solís, Jacob; Jourdain, Elsa; Boulinier, Thierry

2014-01-01

205

Circulation of a Meaban-Like Virus in Yellow-Legged Gulls and Seabird Ticks in the Western Mediterranean Basin  

PubMed Central

In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis), a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus), were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring the spatial and temporal distribution of this flavivirus as well as its potential pathogenicity for animals and humans. PMID:24625959

Cerdà-Cuéllar, Marta; Lecollinet, Sylvie; Pearce-Duvet, Jessica; Busquets, Núria; García-Bocanegra, Ignacio; Pagès, Nonito; Vittecoq, Marion; Hammouda, Abdessalem; Samraoui, Boudjéma; Garnier, Romain; Ramos, Raül; Selmi, Slaheddine; González-Solís, Jacob; Jourdain, Elsa; Boulinier, Thierry

2014-01-01

206

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

USGS Publications Warehouse

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.

Stringfield, W.J.

1995-01-01

207

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

208

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

209

Can seismic character identify lithologies associated with Bluell and Sherwood shorelines and shoals  

SciTech Connect

Several new oil fields have been discovered in the Bluell and Sherwood members of the Mission Canyon Formation, reviving the Mississippian shoreline play in the eastern Williston basin. During periodic regressions, carbonates and evaporites were deposited along the shoreline of a shallow sea. Embayments in the shoreline created traps that contain 3 - 8 million bbl of oil. Carbonate shoals developed offshore. Surrounded by impermeable carbonate mud, they trap 1 - 3 million bbl of oil. The ability of seismic character to distinguish lithologies associated with shorelines and shoals was investigated using sonic logs, models, and seismic data. Shorelines: The gross thickness of the Bluell zone can range between 40 and 70 ft, the Sherwood zone between 35 and 80 ft. Changing thicknesses on geologic models had a distinct effect on seismic character. Also, seismic character varied in response to changing stratigraphy above, within, and below the Bluell and Sherwood zones. Carbonate and anhydrite bulk densities and velocities differ by about 10%. Modeling this difference demonstrated a minimal change in seismic character. Seismic character cannot delineate the shoreline transition from carbonate to anhydrite. Other stratigraphic variations alter seismic character more than this lithologic change. Shoals: Velocity and density variations between shoal carbonates and intershoal mud can differ by 30%. Sonic log seismograms and seismic data show a distinct character change between these lithologies. Seismic character can be used to delineate carbonate shoals and mud. However, the shoal/mud character change can be modified by the seismic response to other stratigraphic variations. Calibration with nearby wells can reduce interpretational uncertainty.

Johnson, E.H. (Balcron Oil, Billings, MT (United States))

1991-06-01

210

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

E-print Network

)- 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

Bech, Claus

211

Infectious bursal disease virus antibodies in eider ducks and Herring Gulls  

USGS Publications Warehouse

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.

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

2000-01-01

212

March 2010 Groundwater Sampling at the Project Shoal Site, Nevada (Data Validation Package)  

SciTech Connect

The U.S. Department of Energy Office of Legacy Management conducted annual sampling at the Project Shoal Area (Shoal) in March 2010. Wells HC-4, HC-5, HC-7, HC-8, MV-1, MV-2 and MV-3 were sampled March 10-12, 2010, as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PLN/S04351, continually updated). Wells HC-1, HC-2, HC-3, and HC-6 were sampled March 24, 2010, by Desert Research Institute personnel.

None

2011-03-01

213

Anatomy of a shoreface sand ridge revisted using foraminifera: False Cape Shoals, Virginia/North Carolina inner shelf  

USGS Publications Warehouse

Certain details regarding the origin and evolution of shelf sand ridges remain elusive. Knowledge of their internal stratigraphy and microfossil distribution is necessary to define the origin and to determine the processes that modify sand ridges. Fourteen vibracores from False Cape Shoal A, a well-developed shoreface-attached sand ridge on the Virginia/North Carolina inner continental shelf, were examined to document the internal stratigraphy and benthic foraminiferal assemblages, as well as to reconstruct the depositional environments recorded in down-core sediments. Seven sedimentary and foraminiferal facies correspond to the following stratigraphic units: fossiliferous silt, barren sand, clay to sandy clay, laminated and bioturbated sand, poorly sorted massive sand, fine clean sand, and poorly sorted clay to gravel. The units represent a Pleistocene estuary and shoreface, a Holocene estuary, ebb tidal delta, modern shelf, modern shoreface, and swale fill, respectively. The succession of depositional environments reflects a Pleistocene sea-level highstand and subsequent regression followed by the Holocene transgression in which barrier island/spit systems formed along the Virginia/North Carolina inner shelf not, vert, ~5.2 ka and migrated landward and an ebb tidal delta that was deposited, reworked, and covered by shelf sand.

Robinson, Marci M.; McBride, Randolph A.

2008-01-01

214

Anatomy of a shoreface sand ridge revisited using foraminifera: False Cape Shoals, Virginia/North Carolina inner shelf  

USGS Publications Warehouse

Certain details regarding the origin and evolution of shelf sand ridges remain elusive. Knowledge of their internal stratigraphy and microfossil distribution is necessary to define the origin and to determine the processes that modify sand ridges. Fourteen vibracores from False Cape Shoal A, a well-developed shoreface-attached sand ridge on the Virginia/North Carolina inner continental shelf, were examined to document the internal stratigraphy and benthic foraminiferal assemblages, as well as to reconstruct the depositional environments recorded in down-core sediments. Seven sedimentary and foraminiferal facies correspond to the following stratigraphic units: fossiliferous silt, barren sand, clay to sandy clay, laminated and bioturbated sand, poorly sorted massive sand, fine clean sand, and poorly sorted clay to gravel. The units represent a Pleistocene estuary and shoreface, a Holocene estuary, ebb tidal delta, modern shelf, modern shoreface, and swale fill, respectively. The succession of depositional environments reflects a Pleistocene sea-level highstand and subsequent regression followed by the Holocene transgression in which barrier island/spit systems formed along the Virginia/North Carolina inner shelf ???5.2 ka and migrated landward and an ebb tidal delta that was deposited, reworked, and covered by shelf sand.

Robinson, M.M.; McBride, R.A.

2008-01-01

215

Temporal trend (1988-2008) of hexabromocyclododecane enantiomers in herring gull eggs from the German coastal region.  

PubMed

Levels of ?-, ?-, and ?-hexabromocyclododecane (HBCD) were determined in pooled eggs from herring gulls (Larus argentatus) sampled on three bird sanctuaries near the German North Sea coast between 1988 and 2008 (Mellum and Trischen) and the German Baltic Sea coast between 1998 and 2008 (Heuwiese) and archived by the German Environmental Specimen Bank. Pressurized fluid extraction, gel permeation chromatography, and LC-MS/MS using (13)C(12)-labelled isotope standards and a chiral column were applied. ?-HBCD was the dominating diastereomer and ranged between 3.7 and 107 ng g(-1)lw while ?- and ?-HBCD were throughout close to LOQ. The highest ?-HBCD concentration was found in eggs from Mellum sampled in the year 2000. Interestingly, HBCD in eggs from the three islands displayed similar time courses with levels increasing to a peak contamination around 2000 and decreasing levels ever since. Chiral signatures of ?-HBCD in eggs differed among the islands but indicated a preferential enrichment of the first eluting enantiomer (-)-?-HBCD. PMID:21216435

Esslinger, Susanne; Becker, Roland; Jung, Christian; Schröter-Kermani, Christa; Bremser, Wolfram; Nehls, Irene

2011-03-01

216

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

NASA Astrophysics Data System (ADS)

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.

Otvos, Ervin G.; Carter, Gregory A.

2013-09-01

217

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

SciTech Connect

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.

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

1995-12-31

218

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

PubMed

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

Conover, Michael R; Vest, Josh L

2009-02-01

219

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

Microsoft Academic Search

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

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

220

Host choice and success of gulls and terns kleptoparasitizing brown pelicans  

Microsoft Academic Search

Little agreement has been reached as to whether kleptoparasitic gulls,Larusspp., preferentially target adult, juvenile or just successful brown pelicans,Pelecanus occidentalis, and no studies have determined kleptoparasite success when targeting pelicans of different age classes. In 1991 and 1992, foraging brown pelicans and kleptoparasitic laughing gulls,L.atricilla, roseate terns,Sterna dougallii, and sandwich terns,S. sandvicensis, were studied to determine host choice, kleptoparasite success

DAVID A SHEALER; TED FLOYD; JOANNA BURGER

1997-01-01

221

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

PubMed Central

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

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

1983-01-01

222

Haematology and blood chemistry of healthy and clinically abnormal great black-backed gulls (Larus Marinus) and herring gulls (Larus Argentatus).  

PubMed

Normal haematological values and cholesterol values (total, HDL-cholesterol, LDL-cholesterol) were determined in free-living Herring and Great Black-backed Gulls, taking into account species, age and sex. These figures were then used as a basis of comparison with findings on birds with apparent clinical abnormalities (the birds were either oiled, emaciated, extensively infested with endoparasites, had external injuries or organic abnormalities). Species-specific differences were found only in cholesterol content; sex-specific differences were not found. There were statistical differences between older birds and nestlings in RBC, PCV, Hb, MCV, MCHC and MCH. An age-related increase between 3- and 6-month-old birds and adults concerning total cholesterol and HDL-cholesterol was evident. The haematological values of healthy gulls showed statistical significant differences in RBC, Hb, MCV, MCHC, MCH, total cholesterol, HDL-cholesterol compared to the values obtained from sick gulls. PMID:18670934

Averbeck, C

1992-01-01

223

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

PubMed

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

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

2000-02-01

224

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

PubMed Central

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

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

2011-01-01

225

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

USGS Publications Warehouse

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.

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

1990-01-01

226

Flock-feeding on fish schools increases individual success in gulls.  

PubMed

Flock-foraging and the role of white plumage in gulls and other seabirds have been the subject of much debate. At first sight it seems that competition within the flock would render flock formation against the interest of the bird who finds the fish school, as the fish must then be shared with birds joining the flock. However, it is also possible that flock formation is neutral or even beneficial to the individual members, including the bird that found the fish (the 'first finder'). Here we show that the fishing success of individual black-headed gulls, Larus ridibundus, increases with flock size up to at least eight birds. Part of the reason is that the fish school is more vulnerable when attacked by several gulls. The first gull to reach a fish school therefore benefits from being joined by others, and conspicuous white upper parts in gulls may act as a means of attracting other gulls to the flock and hence improving hunting success. PMID:3945345

Götmark, F; Winkler, D W; Andersson, M

227

Renal excretion in gull chicks: effect of parathyroid hormone and calcium loading.  

PubMed

Renal clearance experiments were performed on herring gull (Larus argentatus) and great black-backed gull chicks (L. marinus) to test the importance of parathyroid hormone (PTH), parathyroidectomy (PTX), and calcium loading on excretion patterns of sodium, potassium, calcium, and phosphate. PTX reduced the relative clearance of phosphate to near zero within 2 h. Conversely, PTH stimulated net secretion of phosphate within 40 min. Calcium loading caused a drop in phosphate excretion identical to that of PTX, presumably by inhibiting PTH secretion by the parathyroid glands. This also could be reversed by administration of PTH. Serum phosphate values were highest in PTX gulls and lowest in calcium-loaded gulls. The relative clearance of calcium (CCa/CIn) was elevated in calcium-loaded birds. However, CCa/CIn did not change significantly in response to either PTX or PTH in the sham-operated or PTX birds. Serum calcium values were highest in calcium-loaded gulls and lowest in PTX gulls, the reciprocal of the effects on serum phosphate. PMID:3942252

Clark, N B; Mok, L L

1986-01-01

228

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

Microsoft Academic Search

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

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

2000-01-01

229

Spatio-Temporal Structure of Hooded Gull Flocks  

PubMed Central

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

Yomosa, Makoto; Mizuguchi, Tsuyoshi; Hayakawa, Yoshinori

2013-01-01

230

Weathered oil: effect on hatchability of heron and gull eggs  

SciTech Connect

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.

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

1980-08-01

231

Perfluorinated carboxylates and sulfonates and precursor compounds in herring gull eggs from colonies spanning the Laurentian Great Lakes of North America.  

PubMed

Environmentally important perfluorinated carboxylates and sulfonates, as well as per- and polyfluorinated precursor compounds including several sulfonamides, telomer acids, and alcohols were determined in individual herring gull (Larus argentatus) eggs collected (in 2007) from 15 colonies located at Canadian and some American sites across the Laurentian Great Lakes of North America. The pattern of perfluorosulfonates (PFSAs; C6, C8, C10 chain lengths) was dominated by PFOS (> 90% of sigmaPFSA concentration) regardless of collection location. Concentrations of sigmaPFSA were significantly (p < 0.03) higher in eggs from Middle Island (western Lake Erie; 507 +/- 47 ng/g ww), Toronto Harbour (484 +/- 49 ng/g ww), and Strachan Island (486 +/- 59 ng/g ww) (Lake Ontario) compared to eggs from colonies on Lakes Superior, Michigan, and Huron. Perfluorocarboxylic acids (PFCAs) ranging in chain length from C8 to C15 were detected in the eggs, with PFUnA and PFTrA being the dominant compounds. PFOA and PFNA were more abundant in the sigmaPFCA in eggs from Lake Superior and Michigan colonies, and PFUnA and longer chain PFCAs were more abundant in the sigmaPFCA in eggs from Lake Erie and Ontario colonies. In contrast to sigmaPFSA, the highest concentrations of sigmaPFCA were found in eggs from Double Island, Lake Huron (113 +/- 12 ng/g ww) followed by eggs from colonies on Lakes Erie and Ontario. Among the PFOS or PFCA precursor compounds assessed (6:2, 8:2, and 10:2 fluorotelomer alcohols and acids and PFOSA), none were detectable in eggs from any sampling location. The exception was PFOSA (average concentration < 1 ng/g ww), which suggests that PFOS in the gulls and subsequently in their eggs may be due, in part, to biotransformation of PFOSA to PFOS in the gull and/or in their diet and food web. The accumulation of PFSA and PFCA from mainly aquatic dietary sources was suggested, and were highly lake- and/ or colony-dependent especially showing a northwest and southeast spatial trend and with higher concentrations in eggs from colonies in close proximity to highly urbanized and industrialized sites in Lakes Erie and Ontario. PMID:19848159

Gebbink, Wouter A; Hebert, Craig E; Letcher, Robert J

2009-10-01

232

A COMPARISON OF ARGO MERCHANT OIL AND SEDIMENT HYDROCARBONS FROM NANTUCKET SHOALS  

EPA Science Inventory

Surface sediment samples collected from the Nantucket Shoals Argo Merchant wreck site area in February, 1977, were analyzed for hydrocarbon content by gas chromatography. Analysis of sediment grab subsections revealed no clear trend of hydrocarbon contamination as a function of d...

233

Long-term Monitoring Plan for the Shoal Underground Nuclear Test  

SciTech Connect

The flow and transport model of Shoal is used to design a three-well monitoring network to be part of the long-term monitoring network for the site and achieve two objectives: (1) detect the presence of radionuclides in case they migrate to the monitoring well locations, and (2) provide field data to compare with model predictions as part of the model validation process. Using three different quantitative approaches and the numerical groundwater flow and transport model developed for Shoal, three new monitoring well locations were identified from 176 different networks. In addition to the quantitative analyses using the numerical model, the development of the monitoring network for Shoal will also be subject to qualitative hydrogeologic interpretation during implementation. information will only be available during the fieldwork, it will be incorporated in the monitoring well design at the time of well installation. Finally, it should be noted that the CADD-CAP for Shoal, including the compliance boundary, is not yet approved. Should the compliance boundary change from the 1,000-year MCL contaminant boundary, well locations may also need to change. However, the analysis reported here provides a number of alternatives with reasonable detection efficiency.

Ahmed Hassan

2005-02-01

234

Predator shoaling moderates the confusion effect in blue-green chromis, Chromis viridis  

Microsoft Academic Search

Summary In experiments, blue-green chromis [Chromis viridis (Cuvier 1830)] were fed on either scattered or aggregated swarms of brine shrimp (Artemia sp.). Ten runs with each prey dispersion treatment were performed with shoals of one, two, five and ten chromis. The mean lag in reaching peak feeding rate for fish fed on aggregated prey was significantly shorter in the larger

Mark F. L. Smith; Kevin Warburton

1992-01-01

235

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

E-print Network

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

Hutchings, Jeffrey A.

236

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

E-print Network

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

Pineda, Jesús

237

THE ARGO MERCHANT OIL SPILL AND THE SEDIMENTS OF NANTUCKET SHOALS: RESEARCH, LITIGATION AND LEGISLATION  

EPA Science Inventory

On December 15, 1976, the tanker Argo Merchant ran around on Fishing Rip of Nantucket Shoals off the coast of Massachusetts. After several days of stormy weather she broke apart releasing her entire cargo of 28 X 10 to 3rd power metric tons of No. 6 fuel oil into the ocean. Feder...

238

Axial convergence fronts in a barotropic tidal inlet—sand shoal inlet, VA  

Microsoft Academic Search

An axial convergence front system in Sand Shoal Inlet, VA, is analyzed. The fronts, which are parallel to the main channel and mostly within the channel, occur during different tidal stages within a 13-h observation period. A 25-ft boat is used to tow an acoustic Doppler current profiler to measure velocity profiles along an hour-glass shaped ship track. Salinity and

Chunyan Li

2002-01-01

239

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

SciTech Connect

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.

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

1998-07-01

240

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

...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...

2010-11-24

241

Shoals and valley plugs in the Hatchie River watershed  

USGS Publications Warehouse

Agricultural land use and gully erosion have historically contributed more sediment to the streams of the Hatchie River watershed than those streams can carry. In 1970, the main sedimentation problem in the watershed occurred in the tributary flood plains. This problem motivated channelization projects (U.S. Department of Agriculture, 1970). By the mid-1980's, concern had shifted to sedimentation in the Hatchie River itself where channelized tributaries were understood to contribute much of the sediment. The Soil Conservation Service [Natural Resources Conservation Service (NRCS) since 1996] estimated that 640,000 tons of bedload (sand) accumulates in the Hatchie River each year and identified roughly the eastern two-thirds of the watershed, where loess is thin or absent, as the main source of sand (U.S. Department of Agriculture, 1986a). The U.S. Geological Survey (USGS), in cooperation with the West Tennessee River Basin Authority (WTRBA), conducted a study of sediment accumulation in the Hatchie River and its tributaries. This report identifies the types of tributaries and evaluates sediment, shoal formation, and valley-plug problems. The results presented here may contribute to a better understanding of similar problems in West Tennessee and the rest of the southeastern coastal plain. This information also will help the WTRBA manage sedimentation and erosion problems in the Hatchie River watershed.The source of the Mississippi section of the Hatchie River is in the sand hills southwest of Corinth, Mississippi (fig. 1). This section of the Hatchie River flows northward in an artificial drainage canal, gathering water from tributary streams that also are channelized. The drainage canal ends 2 miles south of the Tennessee State line. The Tennessee section of the Hatchie River winds north and west in a meandering natural channel to the Mississippi River. Although most of the Hatchie River tributaries are also drainage canals, the river's main stem has kept most of its natural character. The Hatchie River flows through a wide valley bottom occupied mostly by riverine wetland. Historically, the valley bottom has supported hardwood forests. Since publication of the first Hatchie River report (U.S. Department of Agriculture, 1970), the channel of the river has become shallower, and flooding has increased (U.S. Department of Agriculture 1986b). These wetter conditions inhibit growth of hardwoods and lead to premature hardwood mortality. The NRCS has predicted that despite efforts to control erosion in the uplands, most of the valley-bottom forest will die. '...swamping may be so prevalent as to change most of the Hatchie River Basin flood plain into a marsh condition, with the only remnants of the present bottomland hardwood timber remaining. (U.S. Department of Agriculture, 1986b) Loss of channel depth has been concentrated in short reaches near tributary mouths. At the mouths of Richland, Porters, Clover, and Muddy Creeks, navigation has become difficult for recreational users (Johnny Carlin, West Tennessee River Basin Authority, oral commun., 1998).As the low-gradient alluvial system of the Hatchie River accumulates sediment, another common outcome has been the formation of valley plugs, areas where 'channels are filled with sediment, and all the additional bedload brought downstream is then spread out over the flood plain until a new channel has been formed' (Happ, 1975). Valley plugs typically form where the slope of a sand-laden tributary decreases downstream, or where the tributary joins its parent stream (Happ and others, 1940; Diehl, 1994, 1997; Smith and Diehl, 2000).

Diehl, Timothy H.

2000-01-01

242

Characterization of Escherichia coli populations from gulls, landfill trash, and wastewater using ribotyping.  

PubMed

Due to their opportunistic and gregarious nature, gulls may be important reservoirs and vectors for anthropogenically derived fecal pathogens in coastal areas. We used ribotyping, a genotypic bacterial source tracking method, to compare populations of Escherichia coli among herring gulls Larus argentatus, great black-backed gulls L. marinus, wastewater, and landfill trash in New Hampshire and Maine, USA. Concentrations of E. coli in gull feces varied widely among individuals, but were generally high (6.0 x 10(1) to 2.5 x 10(9) g(-1) wet weight). Of 39 E. coli isolates from L. argentatus, 67% had banding patterns that were > or = 90% similar to those from wastewater and trash, whereas only 39% of 36 L. marinus isolates exhibited > or = 90% similarity to these sources. Strains of E. coli from gulls matched (> or = 90% similarity) more strains from wastewater (39% matching) than from trash (15% matching). E. coli isolates from L. marinus feces exhibited a greater diversity of banding patterns than did isolates from L. argentatus. There were more unique E. coli banding patterns in trash samples than in wastewater, and higher diversity indices in the former compared to the latter. These findings suggest that both species of gulls, especially L. argentatus, obtain fecal bacteria from wastewater and landfill trash, which they may transport to recreational beaches and waters. Our results also indicate that E. coli populations may vary widely between gull species, and between the anthropogenic habitats that they frequent, i.e. landfills and wastewater treatment facilities. PMID:18828562

Nelson, M; Jones, S H; Edwards, C; Ellis, J C

2008-08-19

243

Trophic level determines levels of brominated flame-retardants in coastal herring gulls.  

PubMed

Liver concentrations of eight polybrominated diphenyl ethers (?PBDEs: sum of brominated diphenyl ethers [BDE]-28, -47, -99, -100, -153, -154, -183, and -209) ranged from 135 to 985 ngg(-1) lipid weight (lw) in coastal herring gulls (Larus argentatus) from the marine Hvaler Archipelago (The Glomma River Estuary), Norway. Hexabromocyclododecane (HBCD) concentrations ranged from 10 to 698 ngg(-1)lw. High range in ?(13)C indicates that gulls were subject to a diversity of carbon sources, likely reflecting their mixed feeding on terrestrial and marine organisms, or diversity of autochthonous and allochthonous (watershed) energy sources at the bases of their marine/estuarial food chains. Inverse relationships of HBCD, and to somewhat lesser extent of BDE-209, with ?(13)C values suggest higher abundance of these compounds in the land-derived energy-sources of the gulls. Inverse relationships of BDE-99, BDE-183 and BDE-209 with ?(15)N suggest that trophic relationships affect bioaccumulation of these compounds in the herring gulls, with greater bioaccumulation from lower trophic level prey species. This may be because these PBDE congeners are subject of debromination in higher trophic levels prey species of the gulls (e.g., teleost fish). Levels of BDE-209 (up to 95 ng/g lipid) of these herring gulls from 1998 were in the higher range reported in European birds, and not matched by other reports in North Sea seabirds. The present study suggests that the currently used brominated flame-retardants (BFRs), BDE-209 and HBCD relate to changing nutrient allocation in the herring gulls, and represent a risk to seabirds exploiting near-shore and estuary ecosystems. PMID:21762987

Sørmo, E G; Lie, E; Ruus, A; Gaustad, H; Skaare, J U; Jenssen, B M

2011-10-01

244

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

PubMed

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

Vikøren, T; Stuve, G

1996-04-01

245

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

PubMed Central

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. PMID:23742717

2013-01-01

246

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

Microsoft Academic Search

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

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

2009-01-01

247

The influence of food availability and competition on the use of a feeding site by Herring Gulls Larus argentatus  

Microsoft Academic Search

The feeding distribution of adult and juvenile Herring Gulls at a refuse tip was studied in relation to both spatial and temporal variations in food quality and quantity. The numbers and time of arrival of the gulls at the tip varied in relation to the amount of available food. The extent to which juveniles fed on the high and low

P. Monaghan; N. B. Metcalfe; M. H. Hansell

1986-01-01

248

Growth and behavioral effects of early postnatal chromium and manganese exposure in herring gull ( Larus argentatus) chicks  

Microsoft Academic Search

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

Joanna Burger; Michael Gochfeld

1995-01-01

249

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

Microsoft Academic Search

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,

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

2002-01-01

250

Environmentally acquired lead, cadmium, and manganese in the cattle egret, Bubulcus ibis , and the laughing gull, Larus atricilla  

Microsoft Academic Search

The concentrations of lead, cadmium, and manganese in the tissues of cattle egrets (Bubulcus ibis) and laughing gulls (Larus atricilla) gathered from the Galveston Bay region of Texas were compared, to determine if different patterns of accumulation exist. Their levels in these species were within the range reported for other bird species. Lead levels in bone were comparable, but gulls

Michael Hulse; John S. Mahoney; Gene D. Schroder; Carl S. Hacker; Stanley M. Pier

1980-01-01

251

Comparing the retinal structures and functions in two species of gulls ( Larus delawarensis and Larus modestus) with significant nocturnal behaviours  

Microsoft Academic Search

Ring-billed gulls (Larus delawarensis) and gray gulls (Larus modestus) are two species active both by day and night. We have investigated the retinal adaptations that allow the diurnal and nocturnal behaviours of these two species. Electroretinograms and histological analyses show that both species have a duplex retina in which cones outnumber rods, but the number of rods appears sufficient to

M. P. Emond; R. McNeil; T. Cabana; C. G. Guerra; P. Lachapelle

2006-01-01

252

EGG-LAYING, EGG SIZE, AND SUCCESS IN RELATION TO IMMATURE-MATURE PLUMAGE OF RING-BILLED GULLS  

Microsoft Academic Search

Important direct relationships between the age of parents and their success at hatching eggs and rearing young are known for the Kittiwake (Rissa tri- dactyla) (Coulson and White 1958)) H erring Gull (Larus argentatus) (Par- sons 1971)) and Red-billed Gull (L. novaehollandiue) (Mills 1973). Addi- tionally, egg size, calculated from length and width (Stonehouse 1966) correlates positively with hatchability of

JOHN P. RYDER

253

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

Microsoft Academic Search

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

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

2010-01-01

254

Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast  

Microsoft Academic Search

Organochlorine (OC) residues were measured in eggs and blood of different subspecies of the lesser black-backed gull, Larus fuscus, on the Norwegian coast: a) increasing L. f. intermedius in the North Sea; b) endangered L. f. fuscus near the Arctic Circle; c) L. f. fuscus and greyish-mantled gulls, with a L. f. intermedius appearance, in the Barents Sea region. The

Jan Ove Bustnes; Morten Helberg; Karl-Birger Strann; Janneche Utne Skaare

2006-01-01

255

An outbreak of type C botulism in herring gulls (Larus argentatus) in southeastern Sweden.  

PubMed

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. PMID:17699071

Neimanis, A; Gavier-Widén, D; Leighton, F; Bollinger, T; Rocke, T; Mörner, T

2007-07-01

256

Functional metagenomics reveals previously unrecognized diversity of antibiotic resistance genes in gulls.  

PubMed

Wildlife may facilitate the spread of antibiotic resistance (AR) between human-dominated habitats and the surrounding environment. Here, we use functional metagenomics to survey the diversity and genomic context of AR genes in gulls. Using this approach, we found a variety of AR genes not previously detected in gulls and wildlife, including class A and C ?-lactamases as well as six tetracycline resistance gene types. An analysis of the flanking sequences indicates that most of these genes are present in Enterobacteriaceae and various Gram-positive bacteria. In addition to finding known gene types, we detected 31 previously undescribed AR genes. These undescribed genes include one most similar to an uncharacterized gene in Verrucomicrobium and another to a putative DNA repair protein in Lactobacillus. Overall, the study more than doubled the number of clinically relevant AR gene types known to be carried by gulls or by wildlife in general. Together with the propensity of gulls to visit human-dominated habitats, this high diversity of AR gene types suggests that gulls could facilitate the spread of AR. PMID:22347872

Martiny, Adam C; Martiny, Jennifer B H; Weihe, Claudia; Field, Andrew; Ellis, Julie C

2011-01-01

257

Ultraviolet photopigment sensitivity and ocular media transmittance in gulls, with an evolutionary perspective.  

PubMed

Gulls (Laridae excluding Sternidae) appear to be the only shorebirds (Charadriiformes) that have a short wavelength sensitive type 1 (SWS1) cone pigment opsin tuned to ultraviolet (UV) instead of violet. However, the apparent UV-sensitivity has only been inferred indirectly, via the interpretation that the presence of cysteine at the key amino acid position 90 in the SWS1 opsin confers UV sensitivity. Unless the cornea and the lens efficiently transmit UV to the retina, gulls might in effect be similar to violet-sensitive birds in spectral sensitivity even if they have an ultraviolet sensitive (UVS) SWS1 visual pigment. We report that the spectral transmission of the cornea and lens of great black-backed Larus marinus and herring gulls L. argentatus allow UV-sensitivity, having a lambda(T0.5) value, 344 nm, similar to the ocular media of UV sensitive birds. By molecular sequencing of the second alpha-helical transmembrane region of the SWS1 opsin gene we could also infer that 15 herring gulls and 16 yellow-legged gulls L. michahellis, all base-pair identical, are genetically UV-sensitive. PMID:19308422

Håstad, Olle; Partridge, Julian C; Odeen, Anders

2009-06-01

258

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

PubMed

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

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

2008-10-01

259

Does garbage in the diet improve reproductive output of Glaucous Gulls  

USGS Publications Warehouse

Anthropogenic subsidies are used by a variety of predators in areas developed for human use or residence. If subsidies promote population growth, these predators can have a negative effect on local prey species. The Glaucous Gull (Larus hyperboreus) is an abundant predator in northern Alaska that is believed to benefit from garbage as a supplemental food source, but this supposition has never been tested. In summer 2008 and 2009, we recorded the Glaucous Gull's diet and reproduction at 10 breeding colonies in northern Alaska. Colonies were in industrial, residential, and undeveloped areas and ranged from 5 to 75 km from the nearest landfill. By colony, garbage occurred in zero to 85% of pellets and food remains produced during the chick-rearing period, and the average number of chicks fledged per pair ranged from zero to 2.9. Random-forest analysis indicated that percent occurrence of garbage in the diet was the second most important factor (after number of eggs per pair) explaining variance in fledging rate. There was a significant positive correlation between percent occurrence of garbage in the diet and fledging rate in each year. If this correlation reflects a causal relationship, it suggests that human development that increases gulls' access to garbage could result in increased local gull populations. Such an increase could affect the gulls' natural prey species, including at least 14 species of shorebirds and waterfowl of conservation concern. ?? The Cooper Ornithological Society 2010.

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

2010-01-01

260

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

PubMed

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, or slightly wavy cyst wall without clearly visible protrusions and small (6.0-8.0 ?m) lancet- or banana-shaped cystozoites was identified by the light microscopy. Sarcocysts extracted from one herring gull were used for electron microscopy and DNA analysis. Ultrastructurally, Sarcocystis sp. from the herring gull had the same tissue cyst wall type-1 as S. calchasi, S. columbae, and S. wobeseri parasitizing in birds. According to first internal transcribed spacer (ITS-1) region, 18S rRNA and 28S rRNA gene sequences, Sarcocystis sp. from the herring gull belongs to S. wobeseri. Nevertheless, without evidences of cross-transmission experiment sarcocysts extracted from herring gull at present time are named as S. wobeseri-like. PMID:21597959

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

2011-12-01

261

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

USGS Publications Warehouse

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.

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

1983-01-01

262

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

NASA Astrophysics Data System (ADS)

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.

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

2004-10-01

263

The coastline remote sensing survey for Zhao Shu Island in Xisha Islands based on WorldView-2  

NASA Astrophysics Data System (ADS)

Due to diastrophism, tide action and human activities, the coastline is always in flux. There are lots of coral islands in the south sea of China. Remote sensing survey for the coastline not only can reassert the necessity and importance of coral protection, but also can provide basic data and scientific basis for island ecologic protection, reasonable utilization of land resources. The study area named Zhao Shu Island lies in Jintong Islands of Xisha. It is a coral island which has people inhabited. Using WorldView-2 satellite remote sensing images as data sources we carry out three phases of coastline investigation and monitoring. The satellite data phases are 2002, 2010 and 2013. Firstly, affirm the bands valuable for color composition on the basis of spectral and correlation analysis. Then extract the coastline by a series of image process, such as image correction, fusion, waterline extraction and coastline revision. Finally determine the coastline types and length by artificial interpretation. The results show that the island length is gradually smaller, which means the island area is reducing. The beach bedrock coast in northern island was eroded seriously especially during the period between 2010 and 2013. In addition, the shoal head shape in the western island changed a lot.

Li, Li; Zhong, Chang; Kong, Fanping

2014-11-01

264

Disentangling the effects of group size and density on shoaling decisions of three-spined sticklebacks ( Gasterosteus aculeatus )  

Microsoft Academic Search

Many animals live in groups most of their life. One function of this behaviour is an increased predator protection whereas\\u000a larger groups provide better protection than smaller ones. A causal explanation is that due to a higher number of shoal members\\u000a the individual risk of being predated will decrease (“dilution effect”). Additionally, shoaling leads to increased predator\\u000a confusion. This “confusion

Joachim G. Frommen; Meike Hiermes; Theo C. M. Bakker

2009-01-01

265

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

PubMed

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

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

2014-01-01

266

Island Biogeography  

NSDL National Science Digital Library

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.

John Jungck (BioQUEST Curriculum Consortium; Biology)

2005-12-16

267

Identification and characterization of a novel adenovirus in the cloacal bursa of gulls.  

PubMed

Several viruses of the family of Adenoviridae are associated with disease in birds. Here we report the detection of a novel adenovirus in the cloacal bursa of herring gulls (Larus argentatus) and lesser black-backed gulls (Larus fuscus) that were found dead in the Netherlands in 2001. Histopathological analysis of the cloacal bursa revealed cytomegaly and karyomegaly with basophilic intranuclear inclusions typical for adenovirus infection. The presence of an adenovirus was confirmed by electron microscopy. By random PCR in combination with deep sequencing, sequences were detected that had the best hit with known adenoviruses. Phylogenetic analysis of complete coding sequences of the hexon, penton and polymerase genes indicates that this novel virus, tentatively named Gull adenovirus, belongs to the genus Aviadenovirus. The present study demonstrates that birds of the Laridae family are infected by family-specific adenoviruses that differ from known adenoviruses in other bird species. PMID:23507452

Bodewes, R; van de Bildt, M W G; Schapendonk, C M E; van Leeuwen, M; van Boheemen, S; de Jong, A A W; Osterhaus, A D M E; Smits, S L; Kuiken, T

2013-05-25

268

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

PubMed

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

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

2009-01-01

269

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

PubMed

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

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

2011-07-01

270

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

PubMed Central

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

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

2011-01-01

271

Biochemical and functional disturbances in red blood cells of herring gulls ingesting Prudhoe Bay crude oil.  

PubMed

Heinz body hemolytic anemia developed in Herring Gull (Larus argentatus) nestlings given oral doses of 10 ml of Prudhoe Bay crude oil per kilogram of body weight per day for 5 days. Associated disturbances in red blood cells were increased amounts of reduced glutathione (GSH), peroxidation of membrane lipids, an increase in membrane permeability, and a decrease in the oxygen-carrying capacity of cyanomethemoglobin-convertible hemoglobin. Among groups of gulls given different cumulative doses of oil over a 6-day period, significant covariance with dose and dependence on dose was demonstrated for packed cell volume, hemoglobin, and red cell GSH. Rapid defecation of oil by gulls indicated that the effective dose was substantially less than the administered dose. Pronounced damage to red cells occurred in some birds administered oil for only 2 days. These data imply that the toxic effects of ingested oil may contribute significantly to the morbidity and mortality of oil-contaminated birds. PMID:4049418

Leighton, F A; Lee, Y Z; Rahimtula, A D; O'Brien, P J; Peakall, D B

1985-10-01

272

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

SciTech Connect

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).

DOE/NV

1998-11-01

273

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

274

Critical population density triggers rapid formation of vast oceanic fish shoals.  

PubMed

Similarities in the behavior of diverse animal species that form large groups have motivated attempts to establish general principles governing animal group behavior. It has been difficult, however, to make quantitative measurements of the temporal and spatial behavior of extensive animal groups in the wild, such as bird flocks, fish shoals, and locust swarms. By quantifying the formation processes of vast oceanic fish shoals during spawning, we show that (i) a rapid transition from disordered to highly synchronized behavior occurs as population density reaches a critical value; (ii) organized group migration occurs after this transition; and (iii) small sets of leaders significantly influence the actions of much larger groups. Each of these findings confirms general theoretical predictions believed to apply in nature irrespective of animal species. PMID:19325116

Makris, Nicholas C; Ratilal, Purnima; Jagannathan, Srinivasan; Gong, Zheng; Andrews, Mark; Bertsatos, Ioannis; Godø, Olav Rune; Nero, Redwood W; Jech, J Michael

2009-03-27

275

Multiple S-isotopic evidence for episodic shoaling of anoxic water during Late Permian mass extinction.  

PubMed

Global fossil data show that profound biodiversity loss preceded the final catastrophe that killed nearly 90% marine species on a global scale at the end of the Permian. Many hypotheses have been proposed to explain this extinction and yet still remain greatly debated. Here, we report analyses of all four sulphur isotopes ((32)S, (33)S, (34)S and (36)S) for pyrites in sedimentary rocks from the Meishan section in South China. We observe a sulphur isotope signal (negative ?(34)S with negative ?(33)S) that may have resulted from limitation of sulphate supply, which may be linked to a near shutdown of bioturbation during shoaling of anoxic water. These results indicate that episodic shoaling of anoxic water may have contributed to the profound biodiversity crisis before the final catastrophe. Our data suggest a prolonged deterioration of oceanic environments during the Late Permian mass extinction. PMID:21343928

Shen, Yanan; Farquhar, James; Zhang, Hua; Masterson, Andrew; Zhang, Tonggang; Wing, Boswell A

2011-01-01

276

Multiple S-isotopic evidence for episodic shoaling of anoxic water during Late Permian mass extinction  

PubMed Central

Global fossil data show that profound biodiversity loss preceded the final catastrophe that killed nearly 90% marine species on a global scale at the end of the Permian. Many hypotheses have been proposed to explain this extinction and yet still remain greatly debated. Here, we report analyses of all four sulphur isotopes (32S, 33S, 34S and 36S) for pyrites in sedimentary rocks from the Meishan section in South China. We observe a sulphur isotope signal (negative ?34S with negative ?33S) that may have resulted from limitation of sulphate supply, which may be linked to a near shutdown of bioturbation during shoaling of anoxic water. These results indicate that episodic shoaling of anoxic water may have contributed to the profound biodiversity crisis before the final catastrophe. Our data suggest a prolonged deterioration of oceanic environments during the Late Permian mass extinction. PMID:21343928

Shen, Yanan; Farquhar, James; Zhang, Hua; Masterson, Andrew; Zhang, Tonggang; Wing, Boswell A.

2011-01-01

277

Organochlorine concentrations in diseased vs. healthy gull chicks from the northern Baltic.  

PubMed

The population decline of the nominate lesser black-backed gull Larus fuscus fuscus in the Gulf of Finland (northern Baltic) is caused by an exceedingly high chick mortality due to diseases. The chick diseases include degeneration in various internal organs (primarily liver), inflammations (mainly intestinal), and sepsis, the final cause of death. The hypothesis of starvation causing intestinal inflammations (leading to sepsis) was tested by attempting to reproduce lesions in apparently healthy herring gull L. argentatus chicks in captivity. The herring gull chicks were provided a similar low food-intake frequency as observed for the diseased chicks in the wild. However, empty alimentary tract per se did not induce the intestinal inflammations and therefore, inflammations seem to be innate or caused by other environmental factors in the diseased lesser black-backed chicks. They had very high concentrations of PCB in their liver; but the concentrations were not significantly higher than those of the healthy herring gull chicks, indicating a common exposure area for both species (i.e. the Baltic Sea). When compared to NOEL and LOEL values for TEQs in bird eggs our TEQ levels clearly exceed most or all of the values associated with effects. Compared with published data on fish-eating waterbirds, the DDE concentrations in the diseased lesser black-backed chicks were well above the levels previously correlated with decreased reproduction, while the residues in apparently healthy herring gulls were below those levels. The DDE/PCB ratio in lesser black-backs was significantly elevated, indicating an increased exposure to DDTs as compared with most other Baltic and circumpolar seabirds. The possible exposure areas of DDT in relation to differential migration habits of the two gull species are discussed. PMID:14638302

Hario, Martti; Hirvi, Juha-Pekka; Hollmén, Tuula; Rudbäck, Eeva

2004-01-01

278

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

PubMed

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

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

2006-11-01

279

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

PubMed

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

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

2006-01-01

280

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

PubMed

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

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

2008-05-01

281

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

PubMed

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

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

2008-12-01

282

Can a minority of informed leaders determine the foraging movements of a fish shoal?  

PubMed

There is no information on whether the daily foraging movements of fish shoals are the result of chance, the collective will of all shoalmates, or the leadership of a few individuals. This study tested the latter possibility. Shoals of 12 golden shiners, Notemigonus crysoleucas, were trained to expect food around midday in one of the brightly lit corners of their tank. They displayed daily food-anticipatory activity by leaving the shady area of their tank and spending more and more time in the food corner up to the normal time of feeding. Past this normal time they remained in the shade, even on test days when no food was delivered. Most of these experienced individuals were then replaced by naïve ones. The resulting ratio of experienced:naïve fish could be 5:7, 3:9 or 1:11. On their own, naïve individuals would normally spend the whole day in the shade, but in all tests the experienced individual(s) were able to entrain these more numerous naïve fish out of the shade and into the brightly lit food corner at the right time of day. Entrainment was stronger in the 5:7 than in the 1:11 experiment. The test shoals never split up and were always led by the same fish, presumably the experienced individuals. These results indicate that in a strongly gregarious species, such as the golden shiner, a minority of informed individuals can lead a shoal to food, either through social facilitation of foraging movements or by eliciting following behaviour. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10675263

Reebs

2000-02-01

283

EXPERIMENTS ON THE SHOALING OF NONLINEAR WAVE GROUPS IN A TANK  

E-print Network

AND PROCEDURE Experiments are performed in a wave tank which is 18m long, 1.2m wide and filled to a mean waterEXPERIMENTS ON THE SHOALING OF NONLINEAR WAVE GROUPS IN A TANK L. Shemer1 , Haiying Jiao2 & E. Kit1 of the well-defined wave groups is studied along the sloping bottom in a tank. 2. EXPERIMENTAL FACILITY

Shemer, Lev

284

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

285

Familiarity affects social network structure and discovery of prey patch locations in foraging stickleback shoals  

PubMed Central

Numerous factors affect the fine-scale social structure of animal groups, but it is unclear how important such factors are in determining how individuals encounter resources. Familiarity affects shoal choice and structure in many social fishes. Here, we show that familiarity between shoal members of sticklebacks (Gasterosteus aculeatus) affects both fine-scale social organization and the discovery of resources. Social network analysis revealed that sticklebacks remained closer to familiar than to unfamiliar individuals within the same shoal. Network-based diffusion analysis revealed that there was a strong untransmitted social effect on patch discovery, with individuals tending to discover a task sooner if a familiar individual from their group had previously done so than if an unfamiliar fish had done so. However, in contrast to the effect of familiarity, the frequency with which individuals had previously associated with one another had no effect upon the likelihood of prey patch discovery. This may have been due to the influence of fish on one another's movements; the effect of familiarity on discovery of an empty ‘control’ patch was as strong as for discovery of an actual prey patch. Our results demonstrate that factors affecting fine-scale social interactions can also influence how individuals encounter and exploit resources. PMID:25009061

Atton, N.; Galef, B. J.; Hoppitt, W.; Webster, M. M.; Laland, K. N.

2014-01-01

286

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

SciTech Connect

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.

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

1996-10-01

287

Observations of nonlinear interactions in directionally spread shoaling surface gravity waves  

NASA Technical Reports Server (NTRS)

Shoaling wave fields generated in laboratory experiments were analyzed to determine the sensitivity of nonlinear interactions to the directional distributions of incident waves. Peaks in the directional spectra observed in shallow water were consistent with near resonating, quadratic interactions between two primary waves transferring energy to a third wave with the sum frequency and vector sum wavenumber of the primary waves. Directionally colinear waves forced a higher-frequency wave propagating in the same direction as the primary waves, while directionally spread (i.e., noncolinear) primary waves forced a higher-frequency wave that propagated in a direction between those of the interacting primary waves. Deepwater wave fields with similar frequency spectra but different directional spectra evolved to different shallow-water directional spectra, yet their shallow-water frequency spectra were remarkably similar. This result suggests that the shape of the directional spectrum of the incident wave field has only a small effect on the magnitudes of nonlinear energy transfer during shoaling. The principal effect of directionality in the incident wave field is on the directions, not the amplitudes, of the nonlinearly generated waves. The laboratory data demonstrate clearly the importance of triad interactions between noncolinear and colinear shoaling waves.

Elgar, Steve; Guza, R. T.; Freilich, M. H.

1993-01-01

288

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

PubMed

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

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

2005-10-01

289

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)

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.

Davis, L.; Bishop, J. A.

2013-12-01

290

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

SciTech Connect

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).

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

2006-09-30

291

Haematology and blood chemistry of healthy and clinically abnormal great black?backed gulls (Larus Marinus) and herring gulls (Larus Argentatus)  

Microsoft Academic Search

Normal haematological values and cholesterol values (total, HDL?cholesterol, LDL?cholesterol) were determined in free?living Herring and Great Black?backed Gulls, taking into account species, age and sex. These figures were then used as a basis of comparison with findings on birds with apparent clinical abnormalities (the birds were either oiled, emaciated, extensively infested with endoparasites, had external injuries or organic abnormalities).Species?specific differences

Christiane Averbeck

1992-01-01

292

[Study of protein metabolism of herring gulls (Larus argentatus Pontop.) infected by trematode Himasthla larina (Trematoda: Echinostomatidae)].  

PubMed

The values and dynamics of some indices of protein metabolism were studied in herring gulls Larus argentatus infected with trematode Himasthla larina in natural populations and in experiment. These indices were compared in infected and uninfected birds. Trematode infection considerably affected host protein metabolism irrespective of the age; however, the changes were more pronounced in nestlings. Increased concentration of gamma-globulins, modified albumin, and circulating immune complexes was observed in plasma of infected herring gulls. The experiments demonstrated the most significant changes in protein metabolism of herring gulls 8-11 days after infection with trematode H. larina. PMID:18038623

Kuklina, M M; Kuklin, V V

2007-01-01

293

A note on salmonella excretion in the black headed gull (Larus ribibundus) feeding at sewage treatment works.  

PubMed

The range of salmonella serotypes found in sewage sludge and in the faeces of black headed gulls (Larus ribibundus) feeding on the sludge was investigated. A close association was demonstrated between the serotypes found in both types of sample. Salmonella takoradi (a serotype which is uncommon in Scotland) appeared in the sludge for two short periods during the twelve week study and on both occasions it was later found in the gull faeces. It was shown that gulls become infected after feeding on contaminated sewage sludge but that the infection is probably short-lived. PMID:6746468

Fricker, C R

1984-06-01

294

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

SciTech Connect

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.

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

2000-05-01

295

Organochlorines and heavy metals in Herring Gull ( Larus argentatus ) eggs and chicks from the same clutch  

Microsoft Academic Search

In an earlier paper the authors investigated the intraclutch variability in levels of toxic pollutants and compared this contamination with that of the female Herring Gull (Larus argentatus) after production of the clutch in question. In the present study, they examine the concentrations of contaminants in chicks as compared with one egg of the same clutch. Such studies are important

Peter H. Becker; Hans Sperveslage

1989-01-01

296

Reduced availability of refuse and breeding output in a herring gull (Larus argentatus) colony  

Microsoft Academic Search

We studied the reproductive performance of herring gulls (Larus argentatus) in an old stable colony in SW Finland. Over the period 1993-1997, the colony decreased, and the garbage dumps the birds may have utilised have all closed. This had an effect on the breeding performance of the colony when comparing the year prior to the closing of the last garbage

Mikael Kilpi; Markus Öst

297

Notes on the Standard Body Measurements of Two Populations of Herring Gulls (Larus argentatus )  

Microsoft Academic Search

During the past 20 yr many papers concerned with the circumpolar distribution and systematics of the Herring Gull (Larus argentatus) have been published (e.g. Vouss 1959), with particular reference being paid to northwestern European populations by Barth, who summarized his work in 1975. While large numbers of specimens from Europe have been examined the number from North America has tended

WILLIAM THRELFALL; DAVID D. JEWER

298

Studies on a colony of colour-ringed Herring Gulls Larus argentatus: I. Adult survival rates  

Microsoft Academic Search

Colour-ringed Herring Gulls breeding in a small colony in NE England were used to estimate the average annual adult survival rates of males and females in 6 successive years. Although the female survival rate was higher than that of the males in most years, the difference was not significant. The average annual survival rate for both sexes combined was 91.7%,

J. C. Coulson; J. Butterfield

1986-01-01

299

Induced minisatellite germline mutations in herring gulls ( Larus argentatus) living near steel mills  

Microsoft Academic Search

Despite widespread industrial release of genotoxic contaminants, little is understood of their role in inducing germline mutations in natural populations. We used multilocus DNA fingerprinting to quantify germline minisatellite mutations in families of herring gulls (Larus argentatus) in three nesting categories: (a) near cities with large steel mills operating coking ovens; (b) near cities without steel mills; and (c) in

Carole L Yauk; Glen A Fox; Brian E McCarry; James S Quinn

2000-01-01

300

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

Microsoft Academic Search

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

Craig E. Hebert; Keith A. Hobson; J. Laird Shutt

2000-01-01

301

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

Microsoft Academic Search

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

Joanna Burger; Michael Gochfeld

1995-01-01

302

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

SciTech Connect

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.

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

303

Persistent organic pollutants and mercury in dead and dying glaucous gulls  

Microsoft Academic Search

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

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

304

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

Microsoft Academic Search

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),

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

2009-01-01

305

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

Microsoft Academic Search

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

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

2005-01-01

306

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

Microsoft Academic Search

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

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

2009-01-01

307

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

Microsoft Academic Search

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

Bruce H. Pugesek

1983-01-01

308

California gull chicks raised near colony edges have elevated stress levels  

Microsoft Academic Search

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

Garth Herring; Joshua T. Ackerman

2011-01-01

309

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

Microsoft Academic Search

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.

Bruce H. Pugesek

1981-01-01

310

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

Microsoft Academic Search

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

Bruce H. Pugesek

1990-01-01

311

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

Microsoft Academic Search

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

Bruce H. Pugesek

1995-01-01

312

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

Microsoft Academic Search

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

Daniel Oro; Roger Pradel

2000-01-01

313

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

PubMed

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

Pugesek, B H

1981-05-15

314

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

Microsoft Academic Search

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

Bruce H. Pugesek

1987-01-01

315

GROWTH AND DEVELOPMENT OF KNOWN-AGE RING-BILLED GULL EMBRYOS  

Microsoft Academic Search

This paper describes growth and development of Ring-billed Gull (Larus deelawarensis) embryos. It provides a basis for estimating the age of eggs at previously unvisited colonies. The data also supply a way to determine, within a colony, the location of early and later nesting pairs by comparing, during the same sampling time, relative ages of eggs located in different parts

JOHN P. RYDER; LYNN SOMPPI

316

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

Microsoft Academic Search

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

Kalev Rattiste; Urmas Tartes

2005-01-01

317

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

Microsoft Academic Search

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

J. C. A. Craik

1997-01-01

318

Epidemiology of Influenza A Virus among Black-headed Gulls, the Netherlands, 2006–2010  

PubMed Central

We sampled 7,511 black-headed gulls for influenza virus in the Netherlands during 2006–2010 and found that subtypes H13 and H16 caused annual epidemics in fledglings on colony sites. Our findings validate targeted surveillance of wild waterbirds and clarify underlying factors for influenza virus emergence in other species. PMID:24377955

Verhagen, Josanne H.; Majoor, Frank; Lexmond, Pascal; Vuong, Oanh; Kasemir, Giny; Lutterop, Date; Osterhaus, Albert D.M.E.; Fouchier, Ron A.M.

2014-01-01

319

Unequal sex ratios and their consequences in Herring Gulls ( Larus argentatus )  

Microsoft Academic Search

We observed the sex ratios and age composition of courting, nesting, and nonbreeding birds (in clubs) in four breeding colonies of Herring Gulls in Maine and New York. Breeding pairs, with eggs or chicks, often contained an immature male, but rarely contained an immature female. Similarly, courting pairs contained immature males, but rarely immature females. A higher proportion of courting

Joanna Burger; Michael Gochfeld

1981-01-01

320

Do young Ring-billed Gulls Larus delawarensis participate in territorial defence?  

Microsoft Academic Search

The participation of Ring-billed Gulls and their young in ejecting intruders was compared by observing 13 families in the periphery of a colony in southern Quebec. The frequency of assaults suffered by chicks increased as they got older and the frequency of their jabs, charges and attacks against others also increased with age. Actual fights were less frequent than other

Anne-Marie Dulude; Raymond McNeil; Georg Baron

1988-01-01

321

Occurrence of Candida albicans in fresh gull feces in temperate and subtropical areas  

Microsoft Academic Search

The occurrence ofCandida albicans in fresh gull (Larus spp.) feces was compared in temperate and subtropical locations. Of 239 fresh samples, 133 were obtained in southeastern Connecticut and 106 from different sites on the southeastern and central western coasts of Florida. Overall, 60% of all feces containedC. albicans. Of the Connecticut samples, 78% were positive, whereas 38% of the Florida

John D. Buck

1983-01-01

322

Comparative susceptibility of waterfowl and gulls to highly pathogenic avian influenza H5N1 virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wild avian species in the Orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shorebirds) have traditionally been considered the natural reservoirs for avian influenza viruses (AIV) and morbidity or mortality is rarely associated with AIV infection in these hosts. However, ...

323

ACOUSTIC SIGNALLING OF THE GREAT BLACK-HEADED GULL LARUS ICHTHYAETUS PALLAS  

Microsoft Academic Search

Observations made on the behaviour and sound recordings made of the calls chiefly in the early part of the breeding season in the South Ukraine indicate that the Great Black-headed Gull Larus ichthyaetus has a limited vocal repertoire, producing only eight different types of call associated with various behavioural contexts. Sonagraphic analysis of these sounds shows that their harmonic structure

PRANAS MIERAUSKAS; VALERIE BUZUN

1988-01-01

324

Relationships between reproductive performance and organochlorine contaminants in great black-backed gulls ( Larus marinus)  

Microsoft Academic Search

The great black-backed gull Larus marinus is a top predator in subarctic and temperate marine ecosystems, and the aim of this study was to investigate if organochlorines (OCs) were related to reproductive performance in this species at the subarctic parts of the Norwegian Coast. We measured blood levels of various OCs in 53 breeding birds. The OC levels were relatively

Morten Helberg; Jan Ove Bustnes; Kjell Einar Erikstad; Kai Ove Kristiansen; Janneche Utne Skaare

2005-01-01

325

SEX DETERMINATION OF GREAT BLACK-BACKED GULLS USING MORPHOMETRIC CHARACTERS  

Microsoft Academic Search

We evaluated sexual size dimorphism of Great Black-backed Gulls (Larus marinus) from a breeding colony in the Bay of Fundy and provide a reliable method for predicting the sex of measured individuals. Males were significantly larger than females in all body measurements. A predictive function using only three linear measurements (head length, bill depth and wing length) was more accurate

TONY DIAMOND

326

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

Microsoft Academic Search

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

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

1995-01-01

327

Galapagos Islands  

NASA Technical Reports Server (NTRS)

This true-color image of the Galapagos Islands was acquired on March 12, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. The Galapagos Islands, which are part of Ecuador, sit in the Pacific Ocean about 1000 km (620 miles) west of South America. As the three craters on the largest island (Isabela Island) suggest, the archipelago was created by volcanic eruptions, which took place millions of years ago. Unlike most remote islands in the Pacific, the Galapagos have gone relatively untouched by humans over the past few millennia. As a result, many unique species have continued to thrive on the islands. Over 95 percent of the islands' reptile species and nearly three quarters of its land bird species cannot be found anywhere else in the world. Two of the more well known are the Galapagos giant tortoise and marine iguanas. The unhindered evolutionary development of the islands' species inspired Charles Darwin to begin The Origin of Species eight years after his visit there. To preserve the unique wildlife on the islands, the Ecuadorian government made the entire archipelago a national park in 1959. Each year roughly 60,000 tourists visit these islands to experience what Darwin did over a century and a half ago. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

2002-01-01

328

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

PubMed Central

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

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

2014-01-01

329

Behavior effects of lead exposure on different days for gull (Larus argentatus) chicks.  

PubMed

Lead exposure early in life affects behavioral, physiologic, and intellectual development in humans and other animals. In this article, we examine the effects of temporal differences in lead exposure on early development in herring gulls (Larus argentatus). Each of 72 1-day-old herring gull chicks was randomly assigned to one of six treatment groups to receive a lead nitrate concentration of 100 micrograms/g at age 2 or at age 6, a similar cumulative dose evenly divided on days 2, 4, and 6, or matched-volume saline injections on the same days. Behavioral tests were performed (some at 2- and others at 5-day intervals) to examine locomotion, balance, righting response, thermoregulation, and visual cliff. Most variation in weight was explained by testing age, although treatment affected weight gain for the lead-6 gulls, particularly after 20 days. Although treatment influenced balance and locomotion, the effect was small. The lead-6 birds were unable to remain on an incline as long as the lead-2, lead-246, and control birds. The overall score for balance improved with age for controls, showed little change for the lead-2 and lead-2-4-6 gulls, but showed a decrease in performance for the lead-6 birds. On the thermoregulation test, the lead-6 birds performed less well under both low- and high-temperature test conditions. Although the lead-2-4-6 birds had a lower score on the visual cliff tests than the other groups, the lead-6 gulls showed a significant delay in response and gave significantly fewer calls then the other groups.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7700961

Burger, J; Gochfeld, M

1995-01-01

330

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

PubMed

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

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

2013-01-01

331

Living on the edge: demography of the slender-billed gull in the Western mediterranean.  

PubMed

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

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

2014-01-01

332

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

USGS Publications Warehouse

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.

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

2011-01-01

333

Pilot study of antimicrobial-resistant Escherichia coli in herring gulls (Larus argentatus) and wastewater in the northeastern United States.  

PubMed

Wildlife may be an important reservoir of antibiotic-resistant bacteria and resistance genes. In this pilot study, the prevalence and patterns of antimicrobial resistance in Escherichia coli cultured from wild herring gull (Larus argentatus) feces and human wastewater at Cape Cod, Massachusetts, USA, was compared. Antimicrobial susceptibility was tested using Kirby-Bauer disk diffusion with seven antimicrobial agents. A high proportion of antimicrobial agent-resistant E. coli isolates (59.2%) were detected in wastewater samples compared with a lower prevalence of 17.5% in gull feces. In addition, there was a large proportion of isolates with intermediate susceptibility (93.0%) in gull feces. Although similar resistance patterns and shared resistance genes suggest possible wastewater contamination of the local environment, the relatively low frequency of resistance and high prevalence of intermediate susceptibility detected in E. coli cultured from gull feces depict a complex model of antimicrobial resistance among E. coli strains of wildlife origin. PMID:22946391

Alroy, Karen; Ellis, Julie C

2011-03-01

334

Akpatok Island  

NASA Technical Reports Server (NTRS)

Akpatok Island lies in Ungava Bay in northern Quebec, Canada. Accessible only by air, Akpatok Island rises out of the water as sheer cliffs that soar 500 to 800 feet (150 to 243 m) above the sea surface. The island is an important sanctuary for cliff-nesting seabirds. Numerous ice floes around the island attract walrus and whales, making Akpatok a traditional hunting ground for native Inuit people. This image was acquired by Landsat 7's Enhanced Thematic Mapper plus (ETM+) sensor on January 22, 2001. Image provided by the USGS EROS Data Center Satellite Systems Branch

2002-01-01

335

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

PubMed

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

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

2010-01-01

336

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

SciTech Connect

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.

Ahmed Hassan

2004-09-01

337

Bacteriological analysis of the digestive tube of the mud snail (Bullacta exarata Philippi) and its rearing shoal  

NASA Astrophysics Data System (ADS)

The bacterial flora in the digestive tube of Bullacta exarata Philippi and its rearing shoal were investigated. A total of 157 strains of heterotrophic bacteria, isolated from crop, stomach intestine and other parts of the digestive tube, mainly belong to the genera Photobacterium, Bacillus, Pseudomonas Vibrio and some genera of the family Enterobacteriaceae. There are significantly more varieties of bacteria in crop than in stomach and intestine. A total of 173 strains of bacteria were isolated from the rearing shoal, belonging to 13 genera. The 5 predominant genera, such as Bacillus and Photobacterium, are the same as those in the digestive tube, but greatly differ in percentages. The number of heterotrophic bacteria and Vibrio in rearing shoal change in line with the alteration of the temperature, and are significantly affected by the use of pesticides.

Guoliang, Wang; Tianlun, Zheng; Tongxia, Lu; Yinong, Wang; Hong, Yu; Shan, Jin

2002-10-01

338

Health of herring gulls (Larus argentatus) in relation to breeding location in the early 1990s. I. Biochemical measures.  

PubMed

Tissues of 156 adult herring gulls (Larus argentatus) were sampled in the early 1990s from 11 colonies throughout the Laurentian Great Lakes and 2 reference colonies in Lake Winnipeg and the Bay of Fundy. Gulls from 1 or more Great Lakes differed from Lake Winnipeg or the Bay of Fundy for 17 of 19 clinical biochemical measures, whereas the freshwater and marine reference sites differed in only 3. Three differed with sex. There was little evidence to suggest that these differences reflect genotypic differences. Plasma thyroxine, albumin, calcium, magnesium, inorganic phosphorus, triglyceride, bile acids, total protein, uric acid, and urea nitrogen concentrations and aspartate aminotransferase (AST) activity were lower in gulls from one or more Great Lakes than for gulls from one or both reference sites, while those for globulins and glucose were higher. Highly carboxylated porphyrins accumulated in the livers of Great Lakes gulls and ethoxyresorufin O-deethylase (EROD) activity was induced. There was resistance to PCB/TCDD-induced EROD induction in the Lake Erie colonies. Gulls from five colonies were unable to obtain adequate food to maintain average body condition. Body condition was associated with seven biochemical measures. Colonies in designated Areas of Concern as well as those with high liver polychlorinated biphenyl (PCB) concentrations both differed for 50% of the biochemical measures. Associations between biochemical measures and delta15N-derived trophic position and/or contaminant levels in tissues suggest the effects may be toxicopathic responses. Associations were most frequently with PCBs and dioxin-like contaminants. The health of adult herring gulls varied with breeding location and "lifestyle" in the early 1990s, and Great Lakes gulls suffered from chemical and nutritional stressors that modulated physiological processes and endocrine function. PMID:17687730

Fox, Glen A; Jeffrey, Deborah A; Williams, Kim S; Kennedy, Sean W; Grasman, Keith A

2007-09-01

339

Geographic Variation in Hematological Variables in Adult and Prefledgling Herring Gulls ( Larus argentatus ) and Possible Associations with Organochlorine Exposure  

Microsoft Academic Search

.   The objectives of this study were (1) to describe variation in hematological values found in adult and prefledgling herring\\u000a gulls (Larus argentatus) over a large geographic area, (2) to investigate relationships between hematological variables and other physiological indices,\\u000a and (3) to examine potential associations between exposure to organochlorines and hematological variables. During 1991–93,\\u000a we sampled 160 breeding adult gulls

K. A. Grasman; P. F. Scanlon; G. A. Fox

2000-01-01

340

Introgressive hybridization and the evolutionary history of the herring gull complex revealed by mitochondrial and nuclear DNA  

PubMed Central

Background Based on extensive mitochondrial DNA (mtDNA) sequence data, we previously showed that the model of speciation among species of herring gull (Larus argentatus) complex was not that of a ring species, but most likely due more complex speciation scenario's. We also found that two species, herring gull and glaucous gull (L. hyperboreus) displayed an unexpected biphyletic distribution of their mtDNA haplotypes. It was evident that mtDNA sequence data alone were far from sufficient to obtain a more accurate and detailed insight into the demographic processes that underlie speciation of this complex, and that extensive autosomal genetic analysis was warranted. Results For this reason, the present study focuses on the reconstruction of the phylogeographic history of a limited number of gull species by means of a combined approach of mtDNA sequence data and 230 autosomal amplified fragment length polymorphism (AFLP) loci. At the species level, the mtDNA and AFLP genetic data were largely congruent. Not only for argentatus and hyperboreus, but also among a third species, great black-backed gull (L. marinus) we observed two distinct groups of mtDNA sequence haplotypes. Based on the AFLP data we were also able to detect distinct genetic subgroups among the various argentatus, hyperboreus, and marinus populations, supporting our initial hypothesis that complex demographic scenario's underlie speciation in the herring gull complex. Conclusions We present evidence that for each of these three biphyletic gull species, extensive mtDNA introgression could have taken place among the various geographically distinct subpopulations, or even among current species. Moreover, based on a large number of autosomal AFLP loci, we found evidence for distinct and complex demographic scenario's for each of the three species we studied. A more refined insight into the exact phylogeographic history within the herring gull complex is still impossible, and requires detailed autosomal sequence information, a topic of our future studies. PMID:21067625

2010-01-01

341

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

Microsoft Academic Search

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

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

342

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

USGS Publications Warehouse

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.

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

2003-01-01

343

Distribution and Abundance of Roof-Nesting Gulls in the Great Lakes Region of the United States  

Microsoft Academic Search

In 1994, we conducted aerial, mail, and telephone surveys to determine the distribution and abundance of roof-nesting gulls in states bordering the Great Lakes. We documented more than 7,922 nesting pairs of gulls at 30 colonies in four states; species composition was 71% ring-billed (Larus delawarensis^, 24% herring (Z. argentatus^, and 5% unknown. Colony size ranged from 1 to 1,003

Chris P. Dwyer; Jerrod L. Belant; Richard A. Dolbeer

1996-01-01

344

Sources of Food Delivered to Ring-Billed, Herring and Great Black-Backed Gull Chicks in Marine Environments  

Microsoft Academic Search

Beginning in the 1960s, Ring-billed Gulls' (Larus delawarensis) historic breeding range expanded from inland habitats and freshwater wetlands to marine sites in Atlantic North America. Adults winter on salt water but salt tolerance may entail costs (e.g. maintenance of salt glands) and favor reduced parental use of marine re- sources for feeding chicks. Diets of Ring-billed Gull chicks nesting on

Nicolas R. McLellan; Dave Shutler

2009-01-01

345

Waterfowl predation by and records of the great black-backed gull in Chesapeake Bay during winter and spring  

Microsoft Academic Search

Great black-backed gulls,Larus marinus, were observed to attack and kill lesser scaup, ruddy duck, and the horned grebe in the Chesapeake Bay region during late\\u000a winter and early spring. Waterfowl predation by this gull has been reported in more northern waters. Such behavior is of little\\u000a importance in the total mortaility of ducks. Records indicate that, while sporadic in occurrence,

Romeo J. Mansueti

1961-01-01

346

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

USGS Publications Warehouse

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.

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

1995-01-01

347

Comparing the retinal structures and functions in two species of gulls (Larus delawarensis and Larus modestus) with significant nocturnal behaviours.  

PubMed

Ring-billed gulls (Larus delawarensis) and gray gulls (Larus modestus) are two species active both by day and night. We have investigated the retinal adaptations that allow the diurnal and nocturnal behaviours of these two species. Electroretinograms and histological analyses show that both species have a duplex retina in which cones outnumber rods, but the number of rods appears sufficient to provide vision at night. Their retinas respond over the same scotopic dynamic range of 3.4logcdm(-2), which encompasses all of the light levels occurring at night in their photic environment. The amplitudes of the scotopic saturated a- and b-wave responses as well as the photopic saturated b-wave response and the photopic sensitivity parameter S are however higher in ring-billed gulls than in gray gulls. Moreover, the process of dark adaptation is about 30min faster in gray gulls than in ring-billed gulls. Our results suggest that both species have acquired in the course of their evolution functional adaptations that can be related to their specific photic environment. PMID:16647740

Emond, M P; McNeil, R; Cabana, T; Guerra, C G; Lachapelle, P

2006-09-01

348

Organochlorines in antarctic and arctic avian top predators: a comparison between the South Polar Skua and two species of northern hemisphere gulls.  

PubMed

Different organochlorine compounds (OCs) were measured in the blood of breeding south polar skuas (Catharacta maccormicki) at Svarthamaren, Dronning Maud Land (Antarctica) and compared to those in two species of northern hemisphere gulls: the Arctic glaucous gull (Larus hyperboreus) and the subarctic great black-backed gull (Larus marinus). The skuas had 8% and 29% of the SigmaOC levels (45 ng/g, wet weight) of glaucous gulls (591 ng/g) and great black-backed gulls (158 ng/g), respectively. Polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) were very low in skuas compared to northern gulls, but the mean hexachlorobenzene (HCB) level was 1.7 times higher than in great black-backed gulls and one-third of the glaucous gull level. Mirex levels in skuas were among the highest reported in birds, the mean level being 3 and 26 times higher than those in glaucous gull and great black-backed gulls, respectively. In skuas, the mean levels of HCB, oxychlordane, p,p'-DDE, and PCBs increased by about 30% during a 2-week period, and mirex increased by nearly 60%. In glacuous gulls, HCB, p,p'-DDE, and PCBs increased by 10-20%. For HCB, mirex, and oxychlordane, only a relatively small proportion of the increase in skuas could be explained by changes in lipid pools and the levels at first sampling, compared to glaucous gulls. Thus, skuas were probably accumulating these compounds when present in Antarctica. p,p'-DDE and PCB levels, in contrast, seemed much more stable in the skuas. Relatively high levels of mirex and HCB in south polar skuas are concerning with regard to potential adverse effects. PMID:16683630

Bustnes, Jan O; Tveraa, Torkild; Henden, John A; Varpe, Oystein; Janssen, Kirstin; Skaare, Janneche U

2006-04-15

349

Island Hopping  

ERIC Educational Resources Information Center

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…

Bennett, Gayle

2009-01-01

350

Shell damage and shell repair in the Antarctic limpet Nacella concinna from King George Island  

NASA Astrophysics Data System (ADS)

Nacella concinna is the most conspicuous macroinvertebrate in the intertidal of King George Island. An important predator, the Kelp gull Larus dominicanus, feeds on Nacella during spring low tides. The gulls deposit empty Nacella shells as regurgitates mainly on roosts on coastal rocks. The regurgitates were found to consist of 40% shell fragments by weight and 60% intact shells. Faeces of Kelp gulls contained much smaller fragments than the regurgitates. Some of the Nacella, particularly those too large to ingest, are handled in the intertidal. The middens are, therefore, inadequate to study size selection by Kelp gulls: the largest Nacella are underrepresented. Seventy-five per cent of the intact Nacella shells from the Larus middens showed one or more shell repairs. Such repairs may be due to unsuccessful attacks by gulls, but more probably they indicate damage caused by rolling ice blocks and stones in the intertidal and shallow subtidal. A number of living Nacella were found stranded on the beach, detached from the rocks. They showed damage along the shell margin and even one Nacella was collected without any shell left. The observed repair frequency of 75% in Nacella was much higher than in other (smaller) intertidal gastropods at Potter Peninsula (3-11%, av. 8%). Comparably high frequencies are observed for instance in tropical intertidal gastropods, where repair is due to heavy unsuccessful crab predation; however, shell-crushing crabs are absent on King George Island. This indicates that palaeontologists should be cautious in ascribing all shell repairs in fossil shells (particularly from tidal environments) to predators. Shell repair in the related Nacella deaurata, collected in a less exposed site at Port Stanley (Falkland Islands), occurred only in 13% of the specimens. Another conspicuous form of shell damage was due to grazing by Nacella on the boring algae living in other Nacella shells. Epigrowth of crustose calcareous algae inhibited such grazing, but in the absence of epigrowth deep hollows were scraped in the shells, the parallel scratches by the radula clearly visible, urging Nacella to repair its shell by producing more shelly material on the inside.

Cadée, Gerhard C.

1999-03-01

351

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

Microsoft Academic Search

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.

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

2010-01-01

352

Modeling the effects of aerosols on transmission measurements at Zuniga Shoal, California  

NASA Astrophysics Data System (ADS)

An infrared (IR) signal propagating along a 'line-of-sight' horizontal or slant path within the marine surface layer can encounter substantial perturbations. These perturbations include signal extinction due to molecules or aerosol particles; refractive modulations that can amplify or reduce a signal; and scintillation, which is a higher frequency fluctuation in signal intensity. In an effort to elucidate these issues an infrared transmission link was included in a long term propagation field experiment conducted at Zuniga Shoal to study the effects of environmental conditions on low-altitude laser propagation above the ocean surface. Test periods of one month duration were conducted at various times of the year. The transmission path was 7.2 km long connecting an IR broadbeam transmitter (at about 6.5 m ASL) at the Naval Amphibious Base at Coronado, and an IR telescope receiver at Zuniga Shoal (at about 11.5 m ASL). Both locations are in the general San Diego area. The transmission measurements were made at two wavelengths: near-IR, centered at 1.061 ?m and short-wave IR, centered at 1.622 ?m. In this paper we discuss prominent features of the long-term measurements including diurnal variations and the effects of the marine layer. We also compare the field measurements with the extinction predictions generated by the Advanced Navy Aerosol Model (ANAM), and we discuss how long-term field measurements can be used to tune and correct the ANAM.

Tsintikidis, Dimitris; Hammel, Steve; Frederickson, Paul

2006-08-01

353

March 2011 Groundwater Sampling at the Project Shoal Site (Data Validation Package)  

SciTech Connect

The U.S. Department of Energy Office of Legacy Management conducted annual sampling at the Project Shoal Area (Shoal) in March 2011. Wells HC-1, HC-2, HC-4, HC-5, HC-6, HC-7, MV-1, MV-2 and MV-3 were sampled as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PLN/S04351, continually updated). Two extra tritium samples were collected from well HC-4, one sample (HC-4-400) was collected at about 1/3 of the purge volume (135 gallons), the second sample (HC-4-400) was collected at 2/3 of purge volume (270 gallons). These additional samples were collected prior to completing the well purging process to evaluate the effects well purging has on the analytical results. Samples were not collected from locations HC-3 and HC-8 at the direction of the S.M. Stoller Corporation site lead.

None

2011-07-01

354

Nocturnal Fish Use of New Jersey Marsh Creek and Adjacent Bay Shoal Habitats  

NASA Astrophysics Data System (ADS)

Night-time sampling with gill nets in the Little Egg Harbor estuary revealed a component of the estuarine fish fauna, hitherto poorly documented, which is comprised of relatively large size classes of juvenile and adult life history stages. The fishes Mustelus canis, Pomatomus saltatrix, Paralichthys dentatus, Brevoortia tyrannus, Prionotus evolansand Alosa mediocriswere the most abundant fishes captured. These observations suggest that Mid-Atlantic Bight estuaries are important nurseries for juvenile stages beyond the first year, as well as for the young of the year (YOY). Although many other studies emphasise the importance of estuaries as nurseries for YOY stages, the importance of estuaries to later juvenile life stages has been largely overlooked. This component of estuarine fish fauna has been poorly represented in previous North American studies because of probable gear avoidance, and because most studies are conducted primarily during the day. The authors hypothesise that these later juvenile stages are likely to be important estuarine faunal components in other geographic regions, as well as in the Mid-Atlantic Bight. A descriptive comparison of catches between ebb and flood tide stages, and between bay shoal and tidal marsh creek habitats, suggests that later juvenile and adult stages of several species make tidal migrations into shallow estuarine habitats, such as shoals and marsh creeks, during the night hours.

Rountree, R. A.; Able, K. W.

1997-06-01

355

Model-data comparisons of moments of nonbreaking shoaling surface gravity waves  

NASA Technical Reports Server (NTRS)

The predictions of linear and nonlinear (Boussinesq) shoaling wave models for nonbreaking unidirectional surface gravity waves are compared to field observations, with particular emphasis on quantities that may be important for cross-shore sediment transport. The extensive data sets were obtained on two natural beaches, span water depths between 1 and 10 m, and include incident wave power spectra with narrow, broad, and bimodal shapes. Significant wave heights varied between approximately 30 and 100 cm, and peak periods between approximately 8 and 18 s. The evolution of total variances of sea surface elevation, cross-shore velocity, and horizontal acceleration is modeled at least qualitatively well by both linear and nonlinear theories. Only the nonlinear theory predicts the increasingly asymmetric sea surface elevations and horizontal velocities (pitched-forward wave shapes) and the weaker variation of skewness (difference between crest and trough profiles) which are observed to occur during shoaling. The nonlinear theory also models qualitatively well the large skewed accelerations which occur during the passage of asymmetric waves.

Elgar, Steve; Freilich, M. H.; Guza, R. T.

1990-01-01

356

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

PubMed

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

Herring, Garth; Ackerman, Joshua T

2011-08-01

357

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

PubMed

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

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

2014-01-01

358

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

PubMed

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

Muzzall, Patrick M; Gillilland, Merritt G

2004-06-01

359

Toxicity of Prudhoe Bay crude oil and its aromatic fractions to nestling herring gulls  

SciTech Connect

The physiological effects of a single ingested dose of Prudhoe Bay crude oil (PBC), its aromatic fractions, and PBC/Clorexit emulsion were studied in nestling herring gulls (Larus argentatus). The data showed that the high-molecular-weight aromatic compounds were responsible for retardation of growth and increases in adrenal and nasal gland weight. Little difference was found between PBC and the PBC/Clorexit emulsion although the latter did have a somewhat more marked effect on plasma sodium levels.

Peakall, D.B. (Canadian Wildlife Service, Ottawa, Ontario, Canada); Hallett, D.J.; Bend, J.R.; Foureman, G.L.

1982-02-01

360

Tissue levels of lead in experimentally exposed herring gull (Larus argentatus) chicks  

Microsoft Academic Search

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

Joanna Burger; Michael Gochfeld

1990-01-01

361

Effects of lead on growth in young herring gulls (Larus argentatus)  

Microsoft Academic Search

One?day?old herring gulls (Larus argentatus) were injected intraperitoneally with lead nitrate solution (0.1 or 0.2 mg Pb\\/g) or sterile saline to examine differences in growth rates. Despite the low levels of lead exposure, by d 8 there were significant differences in growth rates as a function of treatment. There were also, by d 8, significant differences in bill length, tarsus

Joanna Burger; Michael Gochfeld

1988-01-01

362

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

Microsoft Academic Search

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

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

1998-01-01

363

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

Microsoft Academic Search

.   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

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

2000-01-01

364

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

Microsoft Academic Search

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

Øystein Varpe

2010-01-01

365

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

PubMed

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

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

2009-11-15

366

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

Microsoft Academic Search

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

Michael R. Conover; John Luft

367

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

USGS Publications Warehouse

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.

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

2011-01-01

368

Proximate and ultimate causes of adoption in ring-billed gulls  

Microsoft Academic Search

From 1987 to 1994, the annual frequency of adoption by breeding pairs at a Lake Erie ring-billed gull,Larus delawarensis, colony ranged from 3 to 37% (average 8%\\/year,N=7 years) and, on average, foster parents raised 0.5 fewer of their own chicks to fledging than pairs that did not adopt. The key evolutionary question is: why do some individuals apparently suffer the

KEVIN M BROWN

1998-01-01

369

Begging as graded signals of need for food in young ring-billed gulls  

Microsoft Academic Search

Recent models suggest that begging vocalizations are honest signals communicating a chick's nutritional needs to its parents. We investigated the effects on begging of short-term food deprivation (‘hunger’) and long-term reduction in body condition under controlled laboratory conditions in ring-billed gulls,Larus delawarensis. We tested two condition groups (high: fed to satiation; low: fed 75% wet mass of high-condition diet) at

STAVROS IACOVIDES; ROGER M EVANS

1998-01-01

370

Ultraviolet photopigment sensitivity and ocular media transmittance in gulls, with an evolutionary perspective  

Microsoft Academic Search

Gulls (Laridae excluding Sternidae) appear to be the only shorebirds (Charadriiformes) that have a short wavelength sensitive\\u000a type 1 (SWS1) cone pigment opsin tuned to ultraviolet (UV) instead of violet. However, the apparent UV-sensitivity has only\\u000a been inferred indirectly, via the interpretation that the presence of cysteine at the key amino acid position 90 in the SWS1\\u000a opsin confers UV

Olle Håstad; Julian C. Partridge; Anders Ödeen

2009-01-01

371

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

Microsoft Academic Search

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

Daniel Oro; Roger Pradel; Jean-Dominique Lebreton

1999-01-01

372

Flock-feeding on fish schools increases individual success in gulls  

Microsoft Academic Search

Flock-foraging and the role of white plumage in gulls and other seabirds have been the subject of much debate1-4. At first sight it seems that competition within the flock would render flock formation against the interest of the bird who finds the fish school, as the fish must then be shared with birds joining the flock. However, it is also

Frank Götmark; David W. Winkler; Malte Andersson

1986-01-01

373

The Shark Assemblage at French Frigate Shoals Atoll, Hawai`i: Species Composition, Abundance and Habitat Use  

Microsoft Academic Search

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

Jonathan J. Dale; Austin M. Stankus; Michael S. Burns; Carl G. Meyer; Richard Unsworth

2011-01-01

374

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

PubMed Central

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

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

2014-01-01

375

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

PubMed

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

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

2010-03-01

376

Occurrence ofCandida albicans in fresh gull feces in temperate and subtropical areas.  

PubMed

The occurrence ofCandida albicans in fresh gull (Larus spp.) feces was compared in temperate and subtropical locations. Of 239 fresh samples, 133 were obtained in southeastern Connecticut and 106 from different sites on the southeastern and central western coasts of Florida. Overall, 60% of all feces containedC. albicans. Of the Connecticut samples, 78% were positive, whereas 38% of the Florida samples revealed the presence of the yeast. Only 1 of 24 samples of fresh brown pelican feces containedC. albicans. Differences inC. albicans occurrence in birds in various locations was ascribed to variations in habitat and feeding behavior. Samples of water from a municipal reservoir in Connecticut were routinely positive, with an average cell density of 20/liter. Two fresh gull samples obtained on the reservoir bank containedC. albicans at an average cell concentration of 5, 200/g. The frequency ofC. albicans in gull droppings was higher than reported by others, and the yeast is common in temperate waters. These findings have important public health implications. PMID:24221652

Buck, J D

1983-07-01

377

Interseasonal variation in blood concentrations of organochlorines in great black-backed gulls (Larus marinus).  

PubMed

In two subsequent breeding seasons (2001 and 2002), we measured 12 organochlorines (OCs), including hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), p,p'-dichlorodiphenyldichloroethylene (DDE), oxychlordane, and eight polychlorinated biphenyl congeners (PCBs), in the blood of the same 25 great black-backed gulls (Larus marinus). The wet-weight concentrations of different OCs in the blood decreased between 45 and 60% from 2001 to 2002. The main reasons for this were lower blood-lipid concentrations and higher body condition in 2002 compared to 2001. The differences in blood lipids and body condition probably resulted from changes in the availability of different prey types between the years. Despite the variation in the blood concentrations of OCs, there was a high predictability of the relative relationship among individuals between the years, especially for the most-persistent compounds (persistent PCBs, oxychlordane, and DDE); that is, individuals with high levels in 2001 still had relatively high levels compared to other individuals in 2002. This suggests that a concentration obtained from a single blood sample is a relatively reliable measurement of OC burdens for individual great black-backed gulls compared to other individuals, independent of changes in mean OC levels within the population. However, by including information about the nutritional status of individuals, more precise interference from samples in different years and locations may be made. Moreover, the great seasonal variation in OC levels within individuals may have implications for how OC monitoring should be conducted in gull populations. PMID:16050599

Bustnes, Jan Ove; Skaare, Janneche Utne; Berg, Vidar; Tveraa, Torkild

2005-07-01

378

Relationships of metals between feathers and diets of black-tailed gull (Larus crassirostris) chicks.  

PubMed

In birds, metal contaminants in feathers are influenced by prey concentrations and environmental quality. In Black-tailed Gull chicks, Cd, Pb and Cu concentrations were strongly correlated between feathers and stomach contents. Between feathers and livers, Pb, Zn and Fe concentrations were significantly correlated. Cd concentrations were within the range of other seabirds and within the background level for bird feathers (<2 ?g/g dw). At the lighthouse, eight chicks exceeded the background for Pb level in feathers (>4 ?g/g dw). Elevated Pb concentrations might be attributed to ingestion of paint-based chips and natural (soil and rocks) sources. There is evidence that the analyzed birds suffered from acute toxicity, including high levels of pecking from conspecifics and increased mortality from elevated Pb levels. It seems likely that these birds might experience negative health effects from this increased Pb exposure. As a result, Black-tailed Gull chick feathers are a very useful monitoring tool for assessing Cd, Pb and Cu contamination. Essential elements such as Fe, Zn, Mn and Cu were all within the acceptable range of normal concentrations for seabird species including gulls and may be maintained by normal homeostatic mechanisms. PMID:24414165

Kim, Jungsoo; Oh, Jong-Min

2014-03-01

379

Isolation, cryopreservation, and mitogenesis of peripheral blood lymphocytes from chickens (Gallus domesticus) and wild herring gulls (Larus argentatus).  

PubMed

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 centrifugation and density gradient isolation of lymphocytes were compared using chicken blood. Significant thrombocyte contamination of density gradient isolated samples (40% to 77% thrombocytes) led to the use of slow-spin centrifugation (2% thrombocytes) for blood from herring gulls. Cryopreserved blood samples were collected from adult and prefledgling herring gulls at sites of low environmental contamination around the Great Lakes and the Bay of Fundy between 1999 and 2002. Cryopreservation decreased the viability of lymphocytes from wild birds, but a high proportion of samples yielded enough live lymphocytes to assess function in culture. Cryopreserved lymphocytes from herring gulls proliferated in response to phytohemagglutinin (PHA), concanavalin-A, phorbol myristate acetate (PMA), PHA plus PMA, and lipopolysaccharide stimulation. Weber and Roswell Park Memorial Institute medium (RPMI) 1640 media were compared for culture of lymphocytes. Weber medium better supported chicken B-lymphocyte proliferation than RPMI 1640 and supported chicken T-lymphocyte proliferation of a similar magnitude as RPMI. Proliferation responses for lymphocytes from prefledgling herring gulls were stronger in Weber medium than RPMI medium, especially for PHA, for which there was no stimulation in RPMI. Proliferation responses of lymphocytes from adult herring gulls were up to twofold greater than that for prefledgling herring gulls. The magnitudes of proliferation responses were similar to that for chicken lymphocytes. These methods have subsequently proven useful in ecotoxicology studies that involve species in remote locations. PMID:15719198

Lavoie, E T; Grasman, K A

2005-05-01

380

Island Panoramic  

USGS Multimedia Gallery

A panoramic view taken from an island in the Yellowstone River.  Upstream is to the right side of the picture while downstream is to the left.  The middle of the picture looks straight across to the descending right bank. ...

381

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

PubMed

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

Kuklin, V V

2001-01-01

382

Characteristics and Mechanisms of Cardiopulmonary Injury Caused by Mine Blasts in Shoals: A Randomized Controlled Study in a Rabbit Model  

PubMed Central

Background Because the characteristics of blast waves in water are different from those in air and because kinetic energy is liberated by a pressure wave at the water-air interface, thoracic injuries from mine blasts in shoals may be serious. The aim of the present study was to investigate the characteristics and mechanisms of cardiopulmonary injury caused by mine blasts in shoals. Methods To study the characteristics of cardiopulmonary injury, 56 animals were divided randomly into three experimental groups (12 animals in the sham group, 22 animals in the land group and 22 animals in the shoal group). To examine the biomechanics of injury, 20 animals were divided randomly into the land group and the shoal group. In the experimental model, the water surface was at the level of the rabbit's xiphoid process, and paper electric detonators (600 mg RDX) were used to simulate mines. Electrocardiography and echocardiography were conducted, and arterial blood gases, serum levels of cardiac troponin I and creatine kinase-MB and other physiologic parameters were measured over a 12-hour period after detonation. Pressures in the thorax and abdomen and the acceleration of the thorax were measured. Conclusion The results indicate that severe cardiopulmonary injury and dysfunction occur following exposure to mine blasts in shoals. Therefore, the mechanisms of cardiopulmonary injury may result from shear waves that produce strain at the water-air interface. Another mechanism of injury includes the propagation of the shock wave from the planta to the thorax, which causes a much higher peak overpressure in the abdomen than in the thorax; as a result, the abdominal organs and diaphragm are thrust into the thorax, damaging the lungs and heart. PMID:24358110

Han, Gengfen; Wang, Ziming; Wang, Jianmin; Yang, Weixiao; Chen, Jing; Kang, Jianyi; Zhang, Sen; Wang, Aimin; Lai, Xinan

2013-01-01

383

2010 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447  

SciTech Connect

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.

None

2011-02-01

384

2008 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447  

SciTech Connect

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

None

2009-03-01

385

Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas  

USGS Publications Warehouse

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.

Hicks, D.W.; Onuf, C.P.; Tunnell, J.W.

1998-01-01

386

Groundwater Model Validation for the Project Shoal Area, Corrective Action Unit 447  

SciTech Connect

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.

None

2008-05-19

387

Oxygen declines and the shoaling of the hypoxic boundary in the California Current  

NASA Astrophysics Data System (ADS)

We use hydrographic data from the California Cooperative Oceanic Fisheries Investigations program to explore the spatial and temporal variability of dissolved oxygen (DO) in the southern California Current System (CCS) over the period 1984-2006. Large declines in DO (up to 2.1 ?mol/kg/y) have been observed throughout the domain, with the largest relative DO declines occurring below the thermocline (mean decrease of 21% at 300 m). Linear trends were significant (p < 0.05) at the majority of stations down to 500 m. The hypoxic boundary (~60 ?mol/kg) has shoaled by up to 90 m within portions of the southern CCS. The observed trends are consistent with advection of low-DO waters into the region, as well as decreased vertical oxygen transport following near-surface warming and increased stratification. Expansion of the oxygen minimum layer could lead to cascading effects on benthic and pelagic ecosystems, including habitat compression and community reorganization.

Bograd, Steven J.; Castro, Carmen G.; Di Lorenzo, Emanuele; Palacios, Daniel M.; Bailey, Helen; Gilly, William; Chavez, Francisco P.

2008-06-01

388

2009 Groundwater Monitoring Report Project Shoal Area, Corrective Action Unit 447  

SciTech Connect

This report presents the 2009 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 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 monitoring in support of site closure. This report summarizes investigation activities associated with CAU 447 that were conducted at the PSA during fiscal year 2009.

None

2010-03-01

389

A QUANTITATIVE ASSESSMENT OF THYROID HISTOPATHOLOGY OF HERRING GULLS (LARUS ARGENTATUS) FROM THE GREAT LAKES AND A HYPOTHESIS ON THE CAUSAL ROLE OF ENVIRONMENTAL CONTAMINANTS  

Microsoft Academic Search

Thyroids from 213 adult herring gulls of both sexes were collected during incubation from nine colonies in the Great Lakes basin of eastern North America between 1974 and 1983, and from a single colony in the Bay of Fundy from 1977 to 1982. Qualitative and quantitative histological assessment revealed that the majority of the gulls from the Great Lakes basin

R. D. Moccia; A. Fox; A. Britton

1986-01-01

390

Egg oiling to reduce hatch-year ring-billed gull numbers on Chicago's beaches during swim season and water quality test results.  

PubMed

A burgeoning ring-billed gull population along Chicago's Lake Michigan beaches contributes to degraded water quality through fecal contamination. Egg oiling was conducted at Chicago's gull colonies to reduce production and the influx of hatch-year (HY) gulls using Chicago's beaches, with a second, long-term objective of eventually reducing adult gull numbers through attrition. We also investigated swim season water quality trends through the course of this work. From 2007 to 2009, 52, 80, and 81%, of nests at the two primary nest colonies had their eggs rendered inviable by corn oil application. Counts of HY and after hatch-year (AHY) gulls were analyzed during treatment years for 10 beaches. Water quality data were available from the Chicago Park District during our three treatment years and the prior year (baseline) for 19 beaches. HY counts declined at all 10 surveyed beaches from the initial year (52% nests with oiled eggs) to subsequent years with ~80% of nests oiled. Overall, HY gulls numbers on beaches decreased 86% from 2007 to 2009. Decreases in beach usage by AHY gulls were not detected. Compared to pretreatment, the number of beaches with improved water quality test rates increased each year through the course of the study. The frequency of water quality tests showing bacterial exceedances compared to 2006 declined at 18 of 19 beaches by 2009. Egg oiling resulted in fewer HY gulls using Chicago's beaches and was likely a beneficial factor for reduced frequencies of swim advisories and swim bans. PMID:22492207

Engeman, Richard M; Hartmann, John W; Beckerman, Scott F; Seamans, Thomas W; Abu-Absi, Sarah

2012-06-01

391

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

Microsoft Academic Search

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

Michael R. Conover; Kimberly S. Lyons

2005-01-01

392

Discrimination of the threat of direct versus tangential approach to the nest by incubating herring and great black-backed gulls  

Microsoft Academic Search

Examined the ability of incubating herring (Larus argentatus) and black-backed (L. marinus) gulls to discriminate between people walking directly toward their nests and those merely walking tangentially by their nests. Study groups varied in their habitat (open vs vegetated) and previous exposure to human disturbance. Herring gulls responded when the experimenter (E) was at a greater distance from the nest

Joanna Burger; Michael Gochfeld

1981-01-01

393

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

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

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

2006-01-01

394

Turbulence and mixing generated by internal waves shoaling on a barrier reef.  

NASA Astrophysics Data System (ADS)

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.

Davis, K. A.; Monismith, S. G.

2008-12-01

395

Fluid Management Plan for Corrective Action Unit 447: Project Shoal Area, Subsurface, Nevada, Rev. No.: 1  

SciTech Connect

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.

Findlay, Rick

2006-01-01

396

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

PubMed

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

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

2000-01-01

397

Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast.  

PubMed

Organochlorine (OC) residues were measured in eggs and blood of different subspecies of the lesser black-backed gull, Larus fuscus, on the Norwegian coast: a) increasing L. f. intermedius in the North Sea; b) endangered L. f. fuscus near the Arctic Circle; c) L. f. fuscus and greyish-mantled gulls, with a L. f. intermedius appearance, in the Barents Sea region. The dominating OCs in lesser black-backed gulls were polychlorinated biphenyls (PCB) and p,p'-dichlorodiphenyldichloroethylene (DDE). DDE and beta-hexachlorocyclohexane (beta-HCH) residues were higher in L. f. fuscus compared to L. f. intermedius and greyish-mantled birds in the Barents Sea region. In the latter area, blood residues of PCB and DDE in lesser black-backed gulls were as high as in great black-backed gulls, Larus marinus, while in the other regions they were lower. The higher DDE residues in endangered L. f. fuscus compared to increasing L. f. intermedius and greyish-mantled birds, which are invading northern Norway, suggest that OCs may have played a role in the population decline of L. f. fuscus, possibly in combination with nutrient stress. PMID:16564607

Bustnes, Jan Ove; Helberg, Morten; Strann, Karl-Birger; Skaare, Janneche Utne

2006-12-01

398

Health of herring gulls (Larus argentatus) in relation to breeding location in the early 1990s. II. Cellular and histopathological measures.  

PubMed

Organosomatic indices, hematological indicators of stress, and histopathological lesions were quantified for over 150 incubating herring gulls (Larus argentatus) sampled in 11 colonies throughout the Great Lakes and reference colonies in Lake Winnipeg and the Bay of Fundy. Of 21 parameters assessed, significantly more differed between Great Lakes colonies and reference colonies than between the two reference colonies. Relative adrenal, kidney, and liver masses of gulls from some Great Lakes colonies were reduced and thyroid masses increased relative to gulls from reference colonies. Foci of cellular atypia were observed in the hepatocytes of two Great Lakes gulls. Chronic periportal hepatitis, lipogranulomas and vacuolation of hepatocytes, and chronic granulomatous interstitial nephritis were more prevalent or severe in gulls from Great Lakes colonies and were associated with contaminants. The kidneys of gulls from the three most contaminated locations were damaged and functionally compromised. Interstitial nephritis was likely the most functionally significant histopathological lesion. Portal-tract fibrosis, granulomatous hepatitis, and kidney tubule dilation/obstruction and splenic enlargement were more prevalent or severe at reference sites and were associated with blood-borne parasites. Amyloid deposits were observed in the spleen, kidneys, or liver of nearly half of the gulls. Associations between the prevalence or severity of lesions and contaminant levels in gull tissues or the trophic level of their diet suggest some lesions are toxicopathic. Associations were most frequently found with planar halogenated aromatic hydrocarbons and lead. The stress response, as measured by the heterophil/lymphocyte ratio, was attenuated in gulls from Areas of Concern and associated with decreased adrenal mass. Our findings suggest that adult Great Lakes gulls suffered from chronic exposure to chemical stressors in the early 1990s sufficient to modulate endocrine function and physiological processes and induce structural changes in tissues. PMID:17687731

Fox, Glen A; Grasman, Keith A; Campbell, G Douglas

2007-09-01

399

Satellite tracking on the flyways of brown-headed gulls and their potential role in the spread of highly pathogenic avian influenza H5N1 virus.  

PubMed

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

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

400

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

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

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

401

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

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 ...

Gong, Zheng

2010-01-01

402

Bathymetry of the Wilderness breach at Fire Island, New York, June 2013  

USGS Publications Warehouse

The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center in St. Petersburg, Florida, collaborated with the U.S. Army Corps of Engineers Field Research Facility in Duck, North Carolina, to collect shallow water bathymetric data of the Wilderness breach on Fire Island, New York, in June 2013. The breach formed in October 2012 during Hurricane Sandy, and the USGS is involved in a post-Sandy effort to map, monitor, and model the morphologic evolution of the breach as part of Hurricane Sandy Supplemental Project GS2-2B: Linking Coastal Vulnerability and Process, Fire Island. This publication includes a bathymetric dataset of the breach and the adjacent nearshore on the ocean side of the island. The objective of the data collection and analysis is to map the bathymetry of the primary breach channel, ebb shoal, and nearshore bar system.

Brownell, Andrew T.; Hapke, Cheryl J.; Spore, Nicholas J.; McNinch, Jesse E.

2015-01-01

403

Extensive mitochondrial introgression in North American Great Black-backed Gulls (Larus marinus) from the American Herring Gull (Larus smithsonianus) with little nuclear DNA impact.  

PubMed

Recent genetic studies have shown that introgression rates among loci may greatly vary according to their location in the genome. In particular, several cases of mito-nuclear discordances have been reported for a wide range of organisms. In the present study, we examine the causes of discordance between mitochondrial (mtDNA) and nuclear DNA introgression detected in North American populations of the Great Black-backed Gull (Larus marinus), a Holarctic species, from the Nearctic North American Herring Gull (Larus smithsonianus). Our results show that extensive unidirectional mtDNA introgression from Larus smithsonianus into Larus marinus in North America cannot be explained by ancestral polymorphism but most likely results from ancient hybridization events occurring when Larus marinus invaded the North America. Conversely, our nuclear DNA results based on 12 microsatellites detected very little introgression from Larus smithsonianus into North American Larus marinus. We discuss these results in the framework of demographic and selective mechanisms that have been postulated to explain mito-nuclear discrepancies. We were unable to demonstrate selection as the main cause of mito-nuclear introgression discordance but cannot dismiss the possible role of selection in the observed pattern. Among demographic explanations, only drift in small populations and bias in mate choice in an invasive context may explain our results. As it is often difficult to demonstrate that selection may be the main factor driving the introgression of mitochondrial DNA in natural populations, we advocate that evaluating alternative demographic neutral hypotheses may help to indirectly support or reject hypotheses invoking selective processes. PMID:24105440

Pons, J-M; Sonsthagen, S; Dove, C; Crochet, P-A

2014-03-01

404

Effects of lead on learning in herring gulls: an avian wildlife model for neurobehavioral deficits.  

PubMed

Lead is one of the most common metals in contaminated ecosystems. Although lead poisoning and mortality have long been known, little is known of the neurobehavioral effects produced by low levels of lead in wild animals. Herein we describe the neurobehavioral effects of lead on learning using herring gulls (Larus argentatus) as a model. Doses used in these studies conducted in the laboratory and in nature were sufficient to produce lead concentrations in feathers that were equivalent to those found in gulls living in the wild. The exposure consisted of a single intraperitoneal injection of 0 and 100mg/kg lead acetate on day 2; each experiment involved 20-30 chicks in a lead-exposed group, and 20-30 chicks in a control group. We examined walking, begging, feeding, behavioral thermoregulation, individual recognition, and treadmill learning. There were significant differences between control and lead-exposed gulls chicks on all testing days. Learning, as well as improvement of motor skills, was faster for control chicks than lead-injected chicks for the thermoregulatory test, individual recognition, and behavior on a treadmill. Lead-injected chicks improved faster than control chicks only for walking scores. In a test where chicks were shown food under a cup, and then tested with three overturned cups, lead-exposed chicks did not show much improvement, whereas control chicks quickly learned where the food was located. The greatest differences in improvement were on the behavioral thermoregulation test, where lead-exposed chicks showed no improvement with age. Overall, this series of experiments indicated that for tasks involving learning, the disparity in accuracy and ability remained regardless of the number of days since exposure-control chicks sometimes improved and learned quicker than did lead-exposed chicks. PMID:15941590

Burger, Joanna; Gochfeld, Michael

2005-08-01

405

Effects of lead and exercise on endurance and learning in young herring gulls.  

PubMed

In this paper, we report the use of young herring gulls, Larus argentatus, to examine the effect of lead and exercise on endurance, performance, and learning on a treadmill. Eighty 1-day-old herring gull chicks were randomly assigned to either a control group or a lead treatment group that received a single dose of lead acetate solution (100mg/kg) at day 2. Controls were injected with an equal volume of isotonic saline at the same age. Half of the lead treatment group and half of the control group were randomly assigned to an exercise regime of walking on a treadmill twice each day. The other group remained in their cages. We test the null hypotheses that neither lead nor exercise affected performance of herring gull chicks when subsequently tested on the treadmill at 7, 11, and 17 days post-injection. Performance measures included latency to orient forward initially, to move continuously, forward on the treadmill, and to avoiding being bumped against the back of the test chamber. Also measured were the number of calls per 15 s, and the time to tire out. Latency to face forward and avoiding being bumped against the back of the test chamber were measures of learning, and time to tire out was a measure of endurance. We found significant differences as a function of lead, exercise, and their interaction, and rejected the null hypotheses. For all measures of behavior and endurance, lead had the greatest contribution to accounting for variability. In general, lead-treated birds showed better performance improvement from the daily exercise than did controlled non-lead birds, with respect to endurance and learning. We suggest that in nature, exercise can improve performance of lead-exposed birds by partially mitigating the effects of lead, thereby increasing survival of lead-impaired chicks. PMID:14759659

Burger, Joanna; Gochfeld, Michael

2004-02-01

406

A benthic survey of Aliwal Shoal and assessment of the effects of a wood pulp effluent on the reef.  

PubMed

Aliwal Shoal lies south of Durban in South Africa and has been the subject of recent bathymetric, seafloor and benthic surveys. ANOVA of the biological data revealed that the biota were uniformly distributed on the reef with the exception of encrusting sponges and algae on rock. The variations in distribution of these biota were significant and, in the case of the encrusting sponges, appeared to be related to the discharge of a wood pulp effluent. Further evidence of this was suggested by stable isotope analyses of representative organisms. The encrusting sponges were recommended as good candidates for further monitoring of the effects of the wood pulp effluent on Aliwal Shoal as the effluent pipeline has been extended. PMID:16271729

Schleyer, Michael H; Heikoop, Jeffrey M; Risk, Michael J

2006-05-01

407

Development and application of a quantitative PCR assay targeting Catellicoccus marimammalium for assessing gull-associated fecal contamination at Lake Erie beaches.  

PubMed

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

Lee, Cheonghoon; Marion, Jason W; Lee, Jiyoung

2013-06-01

408

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.

409

Streamlined Island  

NASA Technical Reports Server (NTRS)

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.

2003-01-01

410

Comparison of lake trout-egg survival at inshore and offshore and shallow-water and deepwater sites in Lake Superior  

USGS Publications Warehouse

We incubated lake trout (Salvelinus namaycush) eggs over winter at shallow (10 m) and deep locations (20 m) on Gull Island Shoal, Lake Superior; at a shallow-water (10 m) site off the mainland (bark point); and in flowing great lakes water at two laboratories. Survival to hatch was significantly higher in the laboratories and averaged 80.9%. In Lake Superior, egg survival among incubators at all sites was significantly higher (p < 0.0001) For incubators that remained buried in spawning substrates (15.1-21.0%) than for incubators that were partially or completely exposed to water currents (1.0-12.6%). Egg survival for incubators that remained buried at the shallow-water sites was significantly higher at bark point (44.6%) than at Gull Island Shoal (21.0%). Egg survival among incubators that remained buried at the deep (14.4%) and shallow-water sites (21.0%) on Gull Island Shoal was not significantly different. Because incubators that were completely buried or partially exposed only appeared to differ in their degree of exposure, we concluded that survival of eggs in the lake was reduced by mechanical stress associated with water turbulence. Lower egg survival at Gull Island Shoal, a known lake trout-spawning site, was not expected and appeared to have been caused by a strong gale that occurred when these eggs were in late epiboly, a sensitive embryological stage. We present a hypothesis suggesting that lake trout recruitment in the Great Lakes is limited by availability of spawning habitat.

Eshenroder, Randy L.; Bronte, Charles R.; Peck, James W.

1995-01-01

411

Express your personality or go along with the group: what determines the behaviour of shoaling perch?  

PubMed Central

Behavioural syndromes, defined as correlated behaviours in different contexts, have been studied across species and taxa including humans as part of a personality concept. While most studies have focused on solitary individuals, less is known on how shoaling fish compromise between own personality and group behaviour. Risk-taking behaviour in 1-year-old perch (Perca fluviatilis) was observed to compare individual behaviour when in a group and when alone. An experimental design gave the fish the choice between foraging in an open area in the presence of a piscivore and hiding in the vegetation. We quantified the variation accountable by the effect of individuals being in a group, individuals alone and repeated measurements, using hierarchical mixed effects models. Within-group variances were low, but when individuals were later tested alone, individual differences explained most of the variation. Still, the individual best linear unbiased predictors (BLUPs) of time spent in the open area, extracted from the random effects of the mixed effects model, were positively correlated with the corresponding BLUPs when alone. The results indicate that individual behavioural traits are to some degree expressed also within groups. Most fish showed a shyer behaviour when alone, but bolder individuals changed less between treatments than did shyer ones, suggesting a more influential role of bold fish in the group. PMID:19586948

Magnhagen, Carin; Bunnefeld, Nils

2009-01-01

412

Using an Automated 3D-tracking System to Record Individual and Shoals of Adult Zebrafish  

PubMed Central

Like many aquatic animals, zebrafish (Danio rerio) moves in a 3D space. It is thus preferable to use a 3D recording system to study its behavior. The presented automatic video tracking system accomplishes this by using a mirror system and a calibration procedure that corrects for the considerable error introduced by the transition of light from water to air. With this system it is possible to record both single and groups of adult zebrafish. Before use, the system has to be calibrated. The system consists of three modules: Recording, Path Reconstruction, and Data Processing. The step-by-step protocols for calibration and using the three modules are presented. Depending on the experimental setup, the system can be used for testing neophobia, white aversion, social cohesion, motor impairments, novel object exploration etc. It is especially promising as a first-step tool to study the effects of drugs or mutations on basic behavioral patterns. The system provides information about vertical and horizontal distribution of the zebrafish, about the xyz-components of kinematic parameters (such as locomotion, velocity, acceleration, and turning angle) and it provides the data necessary to calculate parameters for social cohesions when testing shoals. PMID:24336189

Maaswinkel, Hans; Zhu, Liqun; Weng, Wei

2013-01-01

413

Social behavior of zebrafish: from synthetic images to biological mechanisms of shoaling.  

PubMed

The zebrafish strikes a good balance between system complexity and practical simplicity and as a result it is becoming increasingly frequently utilized in biomedical research as a translational tool. Numerous human brain disorders are associated with abnormal social behavior and the zebrafish has been suggested for modeling such disorders. To start this line of research, however, one may need to first thoroughly examine the laboratory organism, zebrafish, and its features, social behavior in this case. Proper methods need be developed to induce and quantify social behavior. These paradigms may be able to open a window to the brain and facilitate the understanding of the biological mechanisms of social behavior and its abnormalities. This review is based on an oral paper presented at the last Measuring Behavior Conference, and as such it is mainly focused on research conducted in my own laboratory. Tracing the temporal progression of our own work, it discusses questions including what shoaling is, how it can be induced and measured and how it can be utilized in the modeling of certain human brain disorders, for example, alcohol induced abnormalities. PMID:24793400

Gerlai, Robert

2014-08-30

414

Perfluoroalkyl and polyfluoroalkyl substances in entire clutches of Audouin's gulls from the ebro delta.  

PubMed

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±57ngg(-1) yolk wet weight (ww), for b-eggs was of 140±56ngg(-1) yolk ww and for c-eggs, 133±54ngg(-1) yolk ww. PFOS concentration decreased according to the laying order of the eggs, showing significant differences between consecutive eggs. In addition, significant correlation (rs(2)=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

Vicente, Joana; Sanpera, Carola; García-Tarrasón, Manuel; Pérez, Alba; Lacorte, Silvia

2015-01-01

415

Seasonal movements and migration of Pallas's Gulls Larus ichthyaetus from Qinghai Lake, China  

USGS Publications Warehouse

We studied the seasonal movements and migration often Pallas's Gulls Larus ichthyaetus trom Qinghai Lake to assess migratory routes and stopover areas. Each individual was captured and equipped with an 18 g solar-powered Platform Transmitter Terminal (PIT) to track its movements from September 2007 to May 2008. Six individuals remained near Qinghai Lake until the PTTs stopped transmitting. Three individuals flew 50-330 km from Qinghai Lake to nearby salt lakes. One individual departed on 8 December and flew over 1,700 km south-west to arrive at coastal Bangladesh on 9 January 2008. Two individuals flew in October to the Brahmaputra River in Assam, India, remaining in the area for at least one month until one stopped transmitting. The second individual travelled southwest to coastal Bangladesh. Of the two individuals overwintering in Bangladesh, one remained for 67 days before migrating north. The second bird departed after 96 days, and it returned to Qinghai on 10 May 2008 after 48 days in migration. Both individuals that overwintered in coastal Bangladesh arrived much later than the outbreaks of Highly Pathogenic Avian Influenza (HP AI H5N I) in poultry in 2007. This disparity in timing would tentatively suggest that this species was not involved in long-distance movements of the virus. Instead, the converse may be true: previous work demonstrates the potential for virus spill-over trom poultry into gulls and other wild bird species upon arrival into locations with widespread HPAI H5NI outbreaks and environmental contamination.

Muzaffar, S.B.; Takekawa, J.Y.; Prosser, D.J.; Douglas, D.C.; Yan, B.; Xing, Z.; Hou, Y.; Palm, E.C.; Newman, S.H.

2008-01-01

416

The influence of fasting on blood and plasma composition of herring gulls (Larus argentatus).  

PubMed

Populations of scavenging seabird species in the North Sea may fluctuate with an artificial food source: the availability of fishery waste. To document this impact, it is necessary to assess the birds' nutritional status during periods with decreased fishing activity. Reference data for this purpose was collected from 22 herring gulls investigated during laboratory fasting. After 6 d of food deprivation and body mass losses exceeding 15%, the first birds entered starvation phase 3. Comparatively, this is a rather weak fasting capacity. Plasma levels of total protein and thyroid hormones decreased and beta-hydroxybutyrate increased with fasting duration. The leucocyte proportions were shifted from lymphocytes to heterophils. After 3 d of refeeding, most of the fasting changes were reversed. Plasma enzyme activities increased and hematocrit, hemoglobin, and erythrocyte numbers decreased in both fasting and control birds, most likely as a result of experimental stress and repeated blood sampling. Glucose, cholesterol, monocytes, basophils, and glycosylated hemoglobin remained fairly constant. Triglycerides, free fatty acids, uric acid, and urea varied significantly, but changes were not as clearly a result of fasting. Therefore, total protein, beta-hydroxybutyrate, triiodothyronine, thyroxine, and lymphocyte and heterophil percentages may be the most reliable indicators of the nutritional status and the condition of free-living herring gulls. PMID:10438680

Totzke, U; Fenske, M; Hüppop, O; Raabe, H; Schach, N

1999-01-01

417

Electrical activity of the pectoral muscles during gliding and flapping flight in the herring gull ( Larus argentatus )  

Microsoft Academic Search

Summary Electromyographic recording from the pectoral muscles of the herring gull during flight showed that very little muscle activity is associated with gliding flight. However, the integrated gliding potentials could be increased very considerably by loading the bird. The muscle activity during gliding and flapping flight are in accordance with the known energy requirements for these 2 types of flight.

G. Goldspink; C. Mills; K. Schmidt-Nielsen

1978-01-01

418

DNA strand length and EROD activity in relation to two screening measures of genotoxic exposure in Great Lakes herring gulls.  

PubMed

We collected tissues from herring gulls (Larus argentatus) nesting within and outside of the Great Lakes basin. Genotoxin exposure was assessed as fluorescent aromatic compounds (FACs) in bile and SOS Chromotest-inducing activity in muscle extracts. We determined whether these exposures were associated with decreased erythrocyte DNA strand length and/or induction of hepatic ethoxyresorufin-O-deethylase (EROD) activity. FACs were detected in all bile samples. Most muscle extracts produced a positive or marginal SOS response in the presence of S9. SOS induction potentials were strongly associated with dietary trophic level. The median molecular length of DNA isolated from erythrocytes for 14 of 17 adult and 10 of 11 prefledgling collections was reduced compared to the modal class for their respective age group suggesting widespread DNA damage. DNA damage was greatest in gulls from Saginaw Bay, Lake Huron. Median EROD activity in both adults and prefledglings from remote locations was significantly lower than that of gulls from the lower Great Lakes and was not associated with concentrations of benzo[a]pyrene (B[a]P)-like FACs. Our results indicate Great Lakes herring gulls were exposed to genotoxins and Ah-receptor activating agents in biologically significant concentrations in the early 1990s. These agents appear to be persistent bioaccumulative compounds and/or their metabolites. PMID:16220360

Fox, Glen A; White, Paul A; Trudeau, Suzanne; Theodorakis, Chris; Shutt, Laird J; Kennedy, Sean W; Fernie, Kim J

2005-07-01

419

Isolation, Cryopreservation, and Mitogenesis of Peripheral Blood Lymphocytes from Chickens ( Gallus domesticus ) and Wild Herring Gulls ( Larus argentatus )  

Microsoft Academic Search

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

E. T. Lavoie; K. A. Grasman

2005-01-01

420

Evidence of Weak Contaminant-Related Oxidative Stress in Glaucous Gulls (Larus hyperboreus) from the Canadian Arctic  

Microsoft Academic Search

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

Mark Wayland; David J. Hoffman; Mark L. Mallory; Ray T. Alisauskas; Katherine R. Stebbins

2010-01-01

421

Biomonitoring of coastal areas in Tunisia: Stable isotope and trace element analysis in the Yellow-legged Gull  

Microsoft Academic Search

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

Aida Abdennadher; Francisco Ramírez; Mohamed Salah Romdhane; Xavier Ruiz; Lluis Jover; Carolina Sanpera

2010-01-01

422

Low frequency of extra-pair paternity in Common Gulls ( Larus canus ) as revealed by DNA fingerprinting  

Microsoft Academic Search

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

Monika Bukaeifiska; Dariusz Bukacifiski; Jörg Thomas Epplen; Klaus Peter Sauer; Thomas Lubjuhn

1998-01-01

423

The Toxic Effects of Multiple Persistent Organic Pollutant Exposures on the Post-Hatch Immunity Maturation of Glaucous Gulls  

Microsoft Academic Search

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

Kjetil Sagerup; Hans Jørgen S. Larsen; Janneche Utne Skaare; Grethe M. Johansen; Geir Wing Gabrielsen

2009-01-01

424

Population biology of eyeflukes in fish from a large fluvial ecosystem: the importance of gulls and habitat characteristics  

Microsoft Academic Search

Spottail shiners (Notropis hudsonius) were monitored for eyeflukes monthly at four sites in the St. Lawrence River, Quebec, from spring through autumn in 1997 and 1998. In general, mean abundance of Diplostomum spp. in the lens of spottail shiners was highest at sites near large ring-billed gull ( Larus delawarensis) colonies and was higher in 1998 than in 1997. Population

D. J. Marcogliese; S. Compagna; E. Bergeron; J. D. McLaughlin

2001-01-01

425

Nutrient transfer from sea to land: the case of gulls and cormorants in the Gulf of Maine  

Microsoft Academic Search

Summary 1. The structure of communities is influenced by the transport of resources across ecosystem boundaries. Seabirds are capable of introducing large amounts of marine- derived nutrients to land, thereby modifying resource availability to terrestrial species. 2. In this study we investigated the hypothesis that variation in nesting densities of great black-backed gulls Larus marinus and double-crested cormorants Phalacrocorax auritus

JULIE C. ELLIS; JOSE MIGUEL FARINA; JON D. WITMAN

2006-01-01

426

Organochlorine-associated immunosuppression in prefledgling Caspian terns and herring gulls from the Great Lakes: an ecoepidemiological study.  

PubMed Central

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

Grasman, K A; Fox, G A; Scanlon, P F; Ludwig, J P

1996-01-01

427

Flame retardants and methoxylated and hydroxylated polybrominated diphenyl ethers in two Norwegian Arctic top predators: glaucous gulls and polar bears.  

PubMed

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

Verreault, Jonathan; Gabrielsen, Geir W; Chu, Shaogang; Muir, Derek C G; Andersen, Magnus; Hamaed, Ahmad; Letcher, Robert J

2005-08-15

428

Novel flame retardants in urban-feeding ring-billed gulls from the St. Lawrence River, Canada.  

PubMed

This study investigated the occurrence of a comprehensive suite of polybrominated diphenyl ethers (PBDEs) and current-use flame retardants (FRs) in ring-billed gulls breeding in a highly industrialized section of the St. Lawrence River, downstream from Montreal (QC, Canada). Despite major point-sources and diffuse contamination by FRs, nearly no FR data have been reported in birds from this area. Bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (BEHTBP) was detected in 89% of ring-billed gull livers (mean: 2.16 ng/g ww; max: 17.6 ng/g ww). To our knowledge, this is the highest detection frequency and highest concentrations reported thus far in any avian species or populations. Dechlorane Plus (DP) isomers were also particularly abundant (anti-DP detected in 100% and syn-DP in 93% of livers). Other detected FR compounds (3-14% detection) included 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) and ?-1,2-dibromo-4-(1.2-dibromoethyl)-cyclohexane (?-TBECH). Mean BDE-209 (57.2 ± 12.2 ng/g ww) in ring-billed gull livers was unexpectedly high for this midtrophic gull species, exceeding levels reported in several apex raptors such as peregrine falcons. BDE-209's relative contribution to ?PBDEs was on average 25% (exceeding BDE-47 and BDE-99) and contrasted with profiles typically reported for fish-eating gull species. The present study highlighted preoccupying gaps in upcoming FR regulations and stressed the need for further investigation of the sources of FR exposure in highly urbanized areas. PMID:22845168

Gentes, Marie-Line; Letcher, Robert J; Caron-Beaudoin, Elyse; Verreault, Jonathan

2012-09-01

429

Seasonal Enumeration of Fecal Coliform Bacteria from the Feces of Ring-Billed Gulls (Larus delawarensis) and Canada Geese (Branta canadensis)  

PubMed Central

Water suppliers have often implicated roosting birds for fecal contamination of their surface waters. Geese and gulls have been the primary targets of this blame although literature documenting the fecal coliform content of these birds is quite limited. To determine the actual fecal coliform concentrations of these birds, fecal samples from 249 ring-billed gulls and 236 Canada geese in Westchester County, N.Y., were analyzed over a 2-year period. Results indicate that gull feces contain a greater average concentration of fecal coliform bacteria per gram (3.68 × 108) than do goose feces (1.53 × 104); however, average fecal sample weights of the geese were more than 15 times higher than those of the gulls. PMID:10584032

Alderisio, K. A.; DeLuca, N.

1999-01-01

430

Folly Island Tidal Lines  

USGS Multimedia Gallery

Lines of debris from tidal action on Folly Island. Folly Island, a preserve owned by the Maine Coast Heritage Trust, is about 7 acres. It is located in Bartlett Narrows, along the western coast of Mount Desert Island....

431

Folly Island Tidal Lines  

USGS Multimedia Gallery

Lines of debris from tidal action on Folly Island. Folly Island, a preserve owned by the Maine Coast Heritage Trust, is about 7 acres. It is located in Bartlett Narrows, along the western coast of Mount Desert Island....

432

Alcatraz Island  

NSDL National Science Digital Library

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.

2005-01-01

433

Weak response of oceanic dimethylsulfide to upper mixing shoaling induced by global warming  

PubMed Central

The solar radiation dose in the oceanic upper mixed layer (SRD) has recently been identified as the main climatic force driving global dimethylsulfide (DMS) dynamics and seasonality. Because DMS is suggested to exert a cooling effect on the earth radiative budget through its involvement in the formation and optical properties of tropospheric clouds over the ocean, a positive relationship between DMS and the SRD supports the occurrence of a negative feedback between the oceanic biosphere and climate, as postulated 20 years ago. Such a natural feedback might partly counteract anthropogenic global warming through a shoaling of the mixed layer depth (MLD) and a consequent increase of the SRD and DMS concentrations and emission. By applying two globally derived DMS diagnostic models to global fields of MLD and chlorophyll simulated with an Ocean General Circulation Model coupled to a biogeochemistry model for a 50% increase of atmospheric CO2 and an unperturbed control run, we have estimated the response of the DMS-producing pelagic ocean to global warming. Our results show a net global increase in surface DMS concentrations, especially in summer. This increase, however, is so weak (globally 1.2%) that it can hardly be relevant as compared with the radiative forcing of the increase of greenhouse gases. This contrasts with the seasonal variability of DMS (1000–2000% summer-to-winter ratio). We suggest that the “plankton–DMS–clouds–earth albedo feedback” hypothesis is less strong a long-term thermostatic system than a seasonal mechanism that contributes to regulate the solar radiation doses reaching the earth's biosphere. PMID:17901211

Vallina, S. M.; Simó, R.; Manizza, M.

2007-01-01

434

Groundwater flow near the Shoal Site, Sand Springs Range, Nevada: Impact of density-driven flow  

SciTech Connect

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.

Chapman, J.; Mihevc, T.; McKay, A.

1994-09-01

435

The influence of predation by herring gulls Larus argentatus and oystercatchers Haematopus ostralegus on a newly established mussel Mytilus edulis bed in autumn and winter  

NASA Astrophysics Data System (ADS)

Predation by herring gulls Larus argentatus and oystercatchers Haematopus ostralegus was evaluated on a newly established mussel Mytilus edulis bed on tidal flats of the German Wadden Sea. The mussel bed covered an area of 2 ha and showed a decrease in biomass of 40% in the most densely covered parts from August to January. Synchronously, the extent of the mussel bed was reduced, resulting in a decrease of average biomass of 98% over the whole mussel bed. From the beginning of August 1994 to mid January 1995, the average size of mussels increased from 10.7 to 20.3 mm. The P/B-ratio was 0.68 in August and 0.18 between September and November. Herring gulls and oystercatchers were the most important mussel predators. On average, 266 herring gulls and 63 oystercatchers were present on the mussel bed during one low tide; 34% of the herring gulls and 78% of the oystercatchers were observed to be feeding. Herring gulls fed at a rate of 4.2 mussels per minute and oystercatchers at a rate of 1.3 mussels per minute. While herring gulls took the most common mussel sizes (mean: 20 mm), oystercatchers searched for the largest mussels available (mean: 25 mm). Herring gulls consumed 13 mussels/m2 (0.3g AFDW) during one day and oystercatchers 1.7 mussels/m2 (0.1 g AFDW). Predation by birds was compensated by 33% of the production. The proportion removed by bird predation amounted to 10% of abundance and to 16% of biomass (including production). Oystercatchers were responsible for 1% of the reduction in abundance and for 3% of biomass. Removal was highest in the most common size classes of mussels, mainly caused by herring gulls. However, the highest proportion of mussels was eaten in the largest size classes, mainly by oystercatchers. *** DIRECT SUPPORT *** A03B6035 00004

Hilgerloh, G.; Herlyn, M.; Michaelis, H.

1997-08-01

436

Spatial Patterns in a Bioindicator: Heavy Metal and Selenium Concentration in Eggs of Herring Gulls ( Larus argentatus ) in the New York Bight  

Microsoft Academic Search

.   Concentrations of selenium and five heavy metals (lead, cadmium, mercury, chromium, and manganese) in the eggs of herring\\u000a gulls (Larus argentatus) were studied at six breeding colonies in the New York Bight to detect locational differences and to explore their use as\\u000a a bioindicator of point source or nonpoint source pollution. The herring gull is widespread in North America,

M. Gochfeld

1997-01-01

437

Short communication Henslow's swimming crab (Polybius henslowii) as an important food for yellow-legged gulls (Larus cachinnans) in NW Spain  

Microsoft Academic Search

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

Ignacio Munilla

438

Proximate and ultimate causes of adoption in ring-billed gulls.  

PubMed

From 1987 to 1994, the annual frequency of adoption by breeding pairs at a Lake Erie ring-billed gull, Larus delawarensis, colony ranged from 3 to 37% (average 8%/year, N=7 years) and, on average, foster parents raised 0.5 fewer of their own chicks to fledging than pairs that did not adopt. The key evolutionary question is: why do some individuals apparently suffer the costs associated with a behaviour that appears to enhance the fitness of others? From 1992 to 1995, I investigated the proximate and ultimate causes of adoption in ring-billed gulls from the perspectives of both the foster parents and adopted chicks, and tested predictions that differentiated between various competing adaptive and nonadaptive hypotheses that have been proposed to explain it. While I was able to demonstrate a breeding cost, I failed to identify any benefits to foster parents. Thus, the adaptive hypotheses that rely on the foster parents benefiting were not supported (e.g. kin selection, reciprocal altruism, acquisition of parenting experience). From the foster parent's perspective, adoption was mediated through errors in parent-offspring recognition. Under natural conditions, most fostering pairs were tending small chicks (<6 days old) at the time of adoptions; in chick-transfer experiments, resident parents did not discriminate against foreign chicks until their own chicks were 7-9 days old. Chicks (N=25) that subsequently abandoned their natal nests were lighter, and grew at a slower rate, than chicks that survived to fledging in their home broods. Thus, departing chicks were at a survival disadvantage in their home broods. Chicks that gained acceptance into foreign broods where they were older/larger than the resident chicks realized high survival at the expense of their foster siblings and parents. Based upon individual growth rates and the corresponding survival probabilities, disadvantaged chicks approximately doubled their survival chances through foster care. Why has selection not eliminated adoption? I argue that adoption is an evolutionary arms race between the two principle actor groups; disadvantaged chicks, which benefit through foster care, and host parents, which avoid providing foster care (e.g. infanticide). In ring-billed gulls, selection has failed to eliminate adoption because the long-term reproductive cost (estimated at 4%, this study) of an occasional adoption is probably offset by the relatively higher costs associated with stricter kin discrimination mechanisms (e.g. parental infanticide). (c) 1998 The Association for the Study of Animal Behaviour. PMID:9933551

Brown

1998-12-01

439

Surficial geology of the sea floor in west-central Long Island Sound as shown by sidescan-sonar imagery  

USGS Publications Warehouse

We used sidescan-sonar imagery detailing almost 300 km2 of the sea floor in west-central Long Island Sound in conjunction with bathymetry, sediment samples, bottom video, and seismic data to interpret the area's surficial geology. The distribution of sediments and sedimentary environments interpreted from these data sets represents the Quaternary geology, regional bathymetry, and effects of modern tidal- and wave-driven currents. Four distinct sedimentary environments consisting of 1) fine-grained deposition, 2) sorting and reworking, 3) coarse-grained bedload transport, and 4) erosion or nondeposition, were identified and mapped. Relatively low-energy environments prevail where deposition of clayey silts occurs in deeper water throughout the central part of the study area, and in the protected areas of the far northeastern corner. As low-energy environments transition to relatively high-energy environments, sorting and reworking of sand, silty sand, and sand-silt-clay takes place on the flanks of the shoals and over smaller bathymetric highs. Environments of coarse-grained bedload transport, distinguished by sandy sediments with current-derived bedforms, are located on an unnamed shoal in the northwestern part of the study area and directly to the south of this on Stratford Shoal. High-energy conditions are reflected by environments of erosion or nondeposition, which occur on bathymetric highs where gravel and gravelly sediments are present.

McMullen, K.Y.; Poppe, L.J.; DiGiacomo-Cohen, M. L.; Moser, M.S.; Christman, E.B.

2005-01-01

440

Recombinant transthyretin purification and competitive binding with organohalogen compounds in two gull species (Larus argentatus and Larus hyperboreus).  

PubMed

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

Ucán-Marín, Francisco; Arukwe, Augustine; Mortensen, Anne; Gabrielsen, Geir W; Fox, Glen A; Letcher, Robert J

2009-02-01

441

Rotary currents and residual circulation around banks and islands  

NASA Astrophysics Data System (ADS)

A numerical model, developed in polar coordinates, illustrates barotropic flow over banks and around islands. Steady-state flow patterns over circular banks with diameters of a few kilometers to several hundred kilometers illustrate the progressive importance of the Earth's rotation in determining the flow pattern. The flow patterns are asymmetric so that an oscillating flow over banks and around islands results in Eulerian residual currents. When the far field flow is circular clockwise, the effects due to bottom friction and the Earth's rotation work in the same sense and the Eulerian residual currents are directed clockwise (in the Northern Hemisphere) in the shoaling regions. When the far field flow is circular anticlockwise, these two effects are opposed and, if bottom friction dominates, the Eulerian current pattern becomes anticlockwise. Rotary flow conditions occur in a number of regions, and the broad conclusions presented here are predicted to apply around banks and islands (like the Isles of Scilly and the Channel Isles) which are situated in rotary semidiurnal tidal flow conditions.

Pingree, R. D.; Maddock, Linda

1985-08-01