| lead poisoning in the globally threatened marbled teal and white-headed duck in spain. | marbled teal (marmaronetta angustirostris) and white-headed duck (oxyura leucocephala) are the two european ducks threatened with global extinction. we investigated lead (pb) poisoning in stifftails (oxyura spp., n = 83) and marbled teal (n = 80) shot or found dead or moribund in spanish wetlands via gizzard examination and liver, bone, and blood pb analysis. ingested pb shot was present in 32% of shot stifftails and 70 and 43% of dead or moribund stifftails and marbled teal, respectively. lead- ... | 2001 | 11764172 |
| the ruddy duck oxyura jamaicensis in europe: natural colonization or human introduction? | native to north america, ruddy ducks oxyura jamaicensis now occur in 21 countries in the western palaearctic (including iceland) and their expanding population threatens the native white-headed duck, oxyura leucocephala, through hybridization and possibly competition for food and nest sites. we used mitochondrial dna sequences and nuclear microsatellites to test whether the european ruddy duck population is descended solely from the captive population in the uk, which traces to seven individuals ... | 2006 | 16629802 |
| lead isotopes and lead shot ingestion in the globally threatened marbled teal (marmaronetta angustirostris) and white-headed duck (oxyura leucocephala). | lead isotope ratios ((206)pb/(207)pb and (208)pb/(207)pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean=88.9 ppm, maximum=419 ppm; liver: geometric mean=16.8 ppm, maximum=57.0 ppm). some of the marbled teal h ... | 2006 | 16914183 |
| hybridization between white-headed ducks and introduced ruddy ducks in spain. | the ruddy duck, oxyura jamaicensis, was introduced to great britain in the mid-20th century and has recently spread to other western european countries. in spain, ruddy ducks hybridize with the globally endangered white-headed duck, oxyura leucocephala. we assessed the effects of hybridization on the spanish white-headed ducks, which constitute 25% of the global population of this species, using a panel of eight nuclear intron markers, 10 microsatellite loci, and mtdna control region sequences. ... | 2007 | 17257118 |
| differences in the vulnerability of waterbird species to botulism outbreaks in mediterranean wetlands: an assessment of ecological and physiological factors. | avian botulism kills thousands of waterbirds every year, including endangered species, but information about the differences between species in vulnerability to botulism outbreaks and the capacity to act as carriers of clostridium botulinum is still poorly known. here, we estimated the vulnerability to botulism of 11 waterbird species from mediterranean wetlands by comparing the number of affected birds with the census of individuals at risk. the capacity of different species to act as carriers ... | 2016 | 27016572 |
| microhabitat use and diurnal time-activity budgets of white-headed ducks (oxyura leucocephala scopoli, 1769) wintering at burdur lake, turkey. | diurnal time-activity budgets of white-headed ducks were investigated with respect to sex and temporal environmental variables to document behavioral responses to winter conditions and nutritional requirements at burdur lake where the largest winter concentrations occur. behaviors of males and females were recorded separately in randomly selected focal flocks during 1140 sessions. for the entire population a large proportion of time was spent resting. during the day they spent 61% of time restin ... | 2013 | 24506003 |
| morphological reflections of evolutionary adaptations in the tongue of the white-headed duck. | during an organism's evolution, functional adaptations help species to become better suited to their ecological niches. from the morphological aspect, these adaptations are reflected in the anatomical specializations of different organs. specializations of the lingual organ is a critical adaptation of birds, such as the white-headed duck (oxyura leucocephala), that enables their nutritional requirements to be met. for optimal use of the available food resources, the white-headed duck utilizes th ... | 2018 | 29589227 |