how well do food distributions predict spatial distributions of shorebirds with different degrees of self-organization?1. habitat selection models usually assume that the spatial distributions of animals depend positively on the distributions of resources and negatively on interference. however, the presence of conspecifics at a given location also signals safety and the availability of resources. this may induce followers to select contiguous patches and causes animals to cluster. resource availability, interference and attraction therefore jointly lead to self-organized patterns in foraging animals. 2. we anal ...201020337758
surveillance of charadriiformes in northern australia shows species variations in exposure to avian influenza virus and suggests negligible virus prevalence.the virologic surveillance of 4248 charadriiformes since 1992 primarily from coastal northwest australia did not detect any evidence of avian influenza virus (aiv) excretion (test prevalence = 0%; 95% confidence interval [ci]: 0%-0.09%). past exposure to aiv was evident from serologic testing using nucleoprotein (np) competitive-elisa (c-elisa) with an overall seroprevalence of 8.8% (95% ci: 8%-9.7%). the c-elisa seroprevalence of family scolopacidae and genus numenius was significantly higher w ...201425055621
impacts of man-made landscape features on numbers of estuarine waterbirds at low tide.the potential impact of human disturbance on wintering waterbirds using intertidal mudflats was considered by relating their numbers to the presence of nearby footpaths, roads, railroads, and towns. data were obtained for six english estuaries from the wetland bird survey low tide count scheme. counts were undertaken monthly from november to february, and data were available for an average of 2.8 years per estuary for the period 1992-1993 to 1999-2000. count sections and the positions of man-mad ...200212402099
susceptibility of avian hosts to experimental gymnophalloides seoi determine whether avian species are susceptible to infection with gymnophalloides seoi (a human-infecting intestinal trematode), we exposed 7 species of birds with metacercariae obtained from oysters. the birds were necropsied at days 2, 4, and 6 postinfection (pi). the highest worm recovery at day 6 pi was obtained from the kentish plover (charadrius alexandrinus; mean = 56.0%), followed by the mongolian plover (c. mongolus; 49.3%), and the grey plover (pluvialis squatarola; 32.3%). in contr ...200111318587
structural identification of the beta-hydroxy fatty acid-based diester preen gland waxes of shorebirds.the intact c33-c52 diester wax esters of the preen gland of the shorebirds limosa lapponica, pluvialis squatarola, and pluvialis fulva were determined, using synthesized standards, to comprise predominantly c12-c16 beta-hydroxy fatty acids esterified with a c8-c18 fatty acid at the beta-hydroxy position and with predominantly c12-c20 fatty alcohols esterified at the carboxyl group.200717960891
inorganic and organic contaminants in alaskan shorebird eggs.many shorebird populations throughout north america are thought to be declining, with potential causes attributed to habitat loss and fragmentation, reduced prey availability, increased predation, human disturbance, and increased exposure to environmental pollutants. shorebirds may be particularly vulnerable to contaminant exposure throughout their life cycle, as they forage primarily on invertebrates in wetlands, where many contaminants accumulate disproportionately in the sediments. therefore, ...201627059035
mercury concentration in the eggs of four canadian arctic-breeding shorebirds not predicted based on their population statuses.methylmercury is a toxic form of mercury which persists in food webs for long periods of time and biomagnifies up successive trophic levels. shorebirds breeding in the arctic are exposed to methylmercury, derived from both natural and anthropogenic sources, when they ingest their invertebrate prey. populations of many shorebird species are believed to be declining and one hypothesis for these declines is that they are due to detrimental effects of contaminants, including methylmercury. to test t ...201324255861
a new species of microphallus (trematoda: microphallidae) from venezuela.during 1997-1999, a total of 94 crabs, uca rapax were collected from la sabana, la ceiba and el paujil, sucre state, venezuela. of these 36 were infected with metacercariae. two parasites were located in the abdominal muscles and one under the tissue of carapace and gonad. these metacercariae grew to adults in the following genera: levinseniella, microphallus and maritrema, in the period of 2-5 days after feeding experimentally to the rat rattus norvegicus, mice mus musculus and duck cairinia mo ...200417354386
metal and trace element burdens in two shorebird species at two sympatric wintering sites in southern january and november, 1994, ten willets (catoptrophorus semipalmatus) and ten black-bellied plovers (pluvialis squatarola) were collected at a south-facing sandy beach at the north island naval air station (nasni) and ten willets and three plovers were collected at the tijuana slough national wildlife refuge (tsnwr), 16 km to the southeast. concentrations of 19 inorganic analytes were determined in the livers. differences between sexes in diet or abilities to retain some analytes are indicate ...199826205413
short-term effects of reclamation of part of seal sands, teesmouth, on wintering waders and shelduck : i. shorebird diets, invertebrate densities, and the impact of predation on the invertebrates.the invertebrate macrofauna of seal sands, teesmouth, is very limited in species composition. nereis diversicolor has a two-year life cycle; the larger size-class provides the main prey of the birds pluvialis squatarola, numenius arquata and limosa lapponica. hydrobia ulvae is an important food of p. squatarola and calidris canutus. small carcinus maenas occur in late autumn and are taken by the larger shorebirds. small macoma balthica are also taken, but are scarce and not an important bird foo ...197928308862
shorebird community variations indicative of a general perturbation in the mont-saint-michel bay (france).the mont-saint-michel bay located on the east atlantic flyway is the first site in france for wintering shorebirds, with, on average, 53,000 individuals in january. seven species represent 96% of that community: dunlin (calidris alpina), knot (calidris canutus), oystercatcher (haematopus ostralegus), curlew (numenius arquata), grey plover (pluvialis squatarola), bar-tailed godwit (limosa lapponica) and black-tailed godwit (limosa limosa). the international bird census organised by wetlands inter ...200314558463
nereidid polychaetes as the major diet of migratory shorebirds on the estuarine tidal flats at fujimae-higata in japan.the dietary items of five migratory shorebirds, dunlin (calidris alpina), red-necked stint (c. ruficollis), grey plover (pluvialis squatarola), whimbrel (numenius phaeopus) and black-headed gull (larus ridibundus), were examined by analyses of fecal droppings during the birds' migration or wintering and by surveys of macrobenthic fauna around their foraging sites on the tidal flats of fujimae-higata, nagoya, central japan. body parts of nereidid, capitellid, and spionid polychaetes and crustacea ...200717824775
helminth parasites in six species of shorebirds (charadrii) from the coast of belize.thirteen species of helminth parasites were recovered from six species of charadriid shorebirds (aves: charadriiformes) from belize: the ruddy turnstone, arenaria interpres, the snowy plover, charadrius alexandrinus, the semipalmated plover, c. semipalmatus, the killdeer, c. vociferus, the white-rumped sandpiper, calidris fuscicollis, and the black-bellied plover, pluvialis squatarola. cestode species were predominant (n = 8), followed by trematode species (n = 3) and acanthocephala (n = 2). the ...200111562710
concentrations of 17 elements, including mercury, and their relationship to fitness measures in arctic shorebirds and their eggs.exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and this is of particular concern in the arctic. however, little information exists on contaminant levels in arctic-breeding shorebirds, especially in canada. we studied potential contaminants in three biparental shorebird species nesting in nunavut, canada: ruddy turnstones (arenaria interpres), black-bellied plovers (pluvialis squatarola) and semipalmated plovers (charadrius semipalmatus). blood, f ...201020434755
concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of arctic shorebirds.exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the arctic. we assessed potential contaminants (as, be, cd, co, cr, cu, fe, hg, mn, mo, ni, pb, sb, se, tl, v, and zn) at a shorebird breeding site in nunavut, canada. we compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the arctic-based food chain. we tested whether elements in b ...201121762958
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