Katarzyna Kavetska

Mercury and selenium in the muscle of piscivorous common mergansers (Mergus merganser) from a selenium-deficient European country

Although the relationship between mercury (Hg) and selenium (Se) has been studied in wild birds in areas with sufficient or excessive Se levels, little is known about this relationship in areas where the supply of Se is limited. As Hg detoxification is based on the production of biologically inactive Hg-Se complexes, the aim of this study was to investigate the relationships between the concentrations of total mercury (THg), methylmercury (MeHg), inorganic mercury (InHg=THg-MeHg), percent MeHg of THg, Se and molar ratios (THg:Se, MeHg:Se, InHg:Se) in the breast muscle (n=16) of the piscivorous common mergansers (Mergus merganser) from a Se-deficient and moderately Hg-polluted area in Poland. Mergansers were divided into two groups differing in condition (A-very good condition; C-moderate condition). Concentrations of THg, MeHg and Se were determined by atomic absorption spectrometry, modified gas chromatography atomic fluorescence spectroscopy, and spectrofluorometric methods, respectively. In all studied mergansers, mean concentrations of THg, MeHg, InHg, and Se in muscle were 2.63, 1.92, 0.46, and 0.54µgg(-1)dw, respectively. THg and MeHg concentrations in the muscle of group A mergansers were greater than in group C. The ratio of THg:Se was higher in group A than in group C (2.32 vs 1.36; p<0.01), as well as the molar ratio of MeHg:Se (A vs C: 1.98 vs 1.03; p<0.05). Comparisons between mergansers from Poland and Canada showed similar THg and percent MeHg in the muscle, but mergansers from Poland had several times lower Se levels and higher THg:Se ratios (>2.0) than the Canadian mergansers and other European and North American waterbirds. We found statistically significant positive correlations (MeHg-THg, percent MeHg/THg-MeHg, percent InHg/THg-InHg, THg:Se-THg, MeHg:Se-THg, THg:Se-MeHg, MeHg:Se-MeHg, InHg:Se-InHg, MeHg:Se-THg:Se) and some negative correlations (percent InHg/THg-MeHg, percent MeHg/THg-InHg, THg:Se-Se, MeHg:Se-Se). As THg and percent MeHg in the studied mergansers were similar to populations living in non-Se-deficient areas, it is likely that different mechanisms of muscle Hg detoxification have evolved in mergansers populations living in Se-deficient areas.

Quill mites of the subfamily Picobiinae (Acari: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae)

The paper contains a review of quill mites of the subfamily Picobiinae (Acari: Prostigmata: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae). Three new species are described: Picobia mentalis Skoracki et Unsoeld sp. nov. from Picus mentalis Temminck, Neopicobia ea Skoracki et Unsoeld sp. nov. from Celeus flavus (St. Mueller) (type host), C. elegans (St. Mueller), C. torquatus (Boddaert), and Neopicobia freya Skoracki et Unsoeld sp. nov. from Dryocopus galeatus (Temminck) (type host) and Piculus rubiginosus (Swainson). Additionally, six new host species for Picobia heeri Haller, 1878 and 12 new host species for Picobia dryobatis (Fritsch, 1956) are reported. A complete list of the picobiines parasitising birds of the family Picidae is presented in the tabular form.

Digenean communities in the tufted duck [Aythya fuligula (L., 1758)] and greater scaup [A. marila (L., 1761)] wintering in the north-west of Poland.

A total of 124 specimens of the tufted duck, Aythya fuligula, and 63 greater scaup, A. marila, were examined for digenean parasites. Both duck species, which overwinter in a coastal lake connected with the southern Baltic (north-west Poland) were found to support Amblosoma exile, Cyathocotyle prussica, Paracoenogonimus ovatus, Australapatemon minor, Cotylurus cornutus, Echinoparyphium recurvatum, Echinostoma revolutum and Notocotylus attenuatus. In addition, the tufted duck hosted Hypoderaeum conoideum, Bilharziella polonica, Neoeucotyle zakharovi, Renicola mediovitellata, Psilochasmus oxyurus, Psilostomum brevicolle and Cryptocotyle concava; Echinostoma nordiana occurred in the greater scaup only. The two duck species differed significantly in the intensity and abundance of their digenean infection. Aythya marila harboured higher intensity levels and a wider assemblage of digeneans than A. fuligula, and this was likely to be due to differences in the pre-wintering exposure of the duck species to infective stages of these freshwater digeneans. Digenean communities in both duck species, strongly dominated by E. recurvatum, were relatively similar in their structure. No significant sex-dependent differences in digenean infections were revealed, except for the infection with N. attenuatus in A. fuligula. Similarly, there were no significant age-dependent differences (adult versus immature birds) in digenean infections, except for that with N. attenuatus in A. fuligula. The structural similarity between digenean communities in the two duck species is most likely an effect of overlapping diets based on freshwater molluscs, components of the digenean transmission pathway to definitive hosts.

Hepatic and nephric mercury and selenium concentrations in common mergansers, mergus merganser, from baltic region, Europe

The subject of the present study was the piscivorous common mergansers (Mergus merganser). The total mercury (THg), methylmercury (MeHg), selenium (Se) inorganic mercury (InHg; THg - MeHg), percentage of THg that is MeHg (%MeHg), molar ratios (THg:Se, MeHg:Se, InHg:Se), and their mutual relations in livers and kidneys were determined in ducks from an Se-deficient area in Poland. The authors verified a hypothesis that, as a result of living in an Se-deficient region, mergansers from Poland should have higher THg:Se ratios than other waterbirds with similar THg tissue levels. Although a comparison of healthy mergansers from Poland and Canada showed similar THg tissue contents, the group in the present study had a few times lower Se levels and higher THg:Se ratios (overall means >1.7 in both livers and kidneys in all studied individuals) than the Canadian group and other European and North American waterbirds. The authors found significant correlations between various relations, including MeHg-THg, InHg-THg, Se-THg, %MeHg-THg, InHg/%THg-THg, %MeHg/THg-InHg, %InHg/THg-InHg, MeHg:Se-THg:Se, InHg:Se-THg:Se, InHg:Se-MeHg:Se in liver and InHg-THg, Se-THg, Se-InHg, %MeHg-THg, %MeHg-InHg, %InHg/THg-InHg, THg:Se-THg, InHg:Se-THg, MeHg:Se-MeHg, THg:Se-InHg, InHg:Se-InHg, and InHg:Se-THg:Se in kidney. It is likely that the main factor responsible for the high value of THG:Se ratio (>1) in mergansers from Poland is Se deficiency in central and northern Europe. Therefore, this element is unlikely to participate in the detoxification of Hg in these birds.

Revision of the species complex Amidostomum acutum (Lundahl, 1848) (Nematoda: Amidostomatidae)

Most available literature indicates that the most dominant nematode in Anatinae is a cosmopolitan species Amidostomum acutum (Lundahl, 1848). However, studies on wild duck helminthofauna in northwestern Poland suggest that these birds are attacked by not one but three different parasite species, previously described as a single species. Hence the aim of this study was the redescription of the species complex Amidostomum acutum, conducted on a representative sample of parasites and their hosts. The study material consisted of 6,430 nematode individuals, isolated from the digestive tracts of 1,005 wild ducks, representing 17 species. Unsupervised classification was performed using a Kohonen artificial neural network. The analysis confirmed the division of nematodes into three groups corresponding to three species, both for males and females. Taking into account the qualitative characteristics of the parasites, one can 100% accurately identify these species. The three groups of parasites were also significantly different in their ecology, manifested in their distinct host specificity.

Selenium status in sea ducks (Melanitta fusca, Melanitta nigra and Clangula hyemalis) wintering on the southern Baltic coast, Poland

Abstract The aim of this study was to determine the status of selenium in sea ducks wintering in coastal areas of northwestern Poland. The experimental material included samples of liver, kidney, lung and heart obtained from three species of ducks: Melanitta fusca, Melanitta nigra and Clangula hyemalis. Selenium concentrations in the organs were determined using a spectrofluorometric method. The highest Se concentrations were observed in the liver. The average Se liver concentrations in M. fusca, M. nigra and C. hyemalis were 5.3±0.7, 7.2±0.8 and 6.6±0.7 µg/g dry weight (dw), respectively. In M. fusca Se concentration in the examined organs was observed to occur in the following descending order: liver > kidney > heart > lung, and in M. nigra and C. hyemalis it was liver > lung > kidney > heart. Statistical analysis of the results showed differences in Se concentrations in analogous organs between the investigated species of ducks. In all the organs of M. nigra Se concentration was significantly higher compared to M. fusca.

Streptocara formosensis Sugimoto, 1930 (Nematoda: Acuariidae) in wild ducks from the southern coast of the Baltic Sea

SummaryAlthough nematofauna of wild ducks in north-western Poland seems to be quite well known, researchers still discover species that are new for the fauna of this region and Europe in general. One of them is Streptocara formosensis Sugimoto, 1930 with distinct ecological specificity (the nematode parasites only ducks wintering in the southern Baltic Sea) and topospecificity (limited to the gizzard). During parasitological research on 1005 wild ducks representing 17 species, 13,333 nematodes were isolated, 360 of which (2.7 %) were identified as Streptocara formosensis Sugimoto, 1930. The distinguishing feature of this species from other nematodes of the genus Streptocara (Railliet, Henry and Sisoff, 1912) is the absence of a collar and a specific arrangement of deirids at the nerve ring. During the study, the nematodes were located only under the stratum corneum of the gizzard, lying down in the form of characteristic white “springs.” This is the first observation of this parasite in the nematofauna of Polish wild birds. The nematode was found in 84 (8.35 %) wild ducks representing 7 species: Aythya Marila (Aythyini), Bucephala clangula, Clangula hyemalis, Melanitta nigra, M. fusca, Mergus merganser, Mergellus albellus (Mergini). The highest prevalence (36.7 %) occurred in mergansers; the coefficient of dominance showed that S. formosensis is a subdominant species in B. clangula, C. hyemalis and M. merganser, and a rare species in other hosts. The presence of the parasite in only three out of 157 examined A. marila suggests that the greater scaup is only an accidental host for the nematode.

Two new species of the syringophilid quill mites (Acari: Prostigmata: Syringophilidae) parasitizing apodiform birds (Aves: Apodiformes)

Two new syringophilid species (Acariformes: Syringophilidae) are described, Apodisyringiana hirundapi sp. nov. from Hirundapus caudacutus (Latham) from Japan and Syringophiloidus apus sp. nov. from Apus melba (Linnaeus) from Chile.

Syringophilid mites (Acari: Syringophilidae) associated with the rails (Aves: Rallidae) and a key to the species of the genus Rafapicobia Skoracki, 2011

The fauna of quill mites of the family Syringophilidae Lavoipierre, 1953 (Acari: Prostigmata Cheyletoidea) parasitising birds of the family Rallidae Vigors (Gruiformes) is updated. A new species, Rafapicobia melzeri n. sp. (subfamily Picobiinae), is described from four host species: Rallus aquaticus Linnaeus (type-host) from Germany, Pardirallus sanguinolentus (Swainson) from Chile, Porzana porzana (Linnaeus) from France and P.parva (Scopoli) from Kirghizia. The new species is most similar to R. lepidocolaptesi Skoracki & Solarczyk, 2012 but differs in the absence of agenital plates and the length ratios of setae ag2:g1 and vi:ve:si in females and in the punctate ornament on the hysteronotal and the pygidial shields in males. A key to the species of the genus Rafapicobia is proposed. This is the first record of a representative of the subfamily Picobiinae on gruiform birds. Additionally, new rallid hosts are reported for Charadriphilus ralli Skoracki & Bochkov, 2010 (subfamily Syringophilinae): Gallinula melanops (Vieillot) from Chile, Laterallus melanophaius (Vieillot) from Paraguay, and P.parva (Scopoli) from Kirghizia.

STOMACH NEMATODES OF WILD DUCKS (SUBFAMILY ANATINAE ) WINTERING IN THE NORTH-WESTERN POLAND

Abstract The purpose of this study was to present the structure of nematofauna community with particular emphasis on stomach (proventriculus and gizzard) nematodes in wild ducks wintering in large numbers in the North-Western Poland. Hosts (n=152) were represented by 17 species from eight genera belonging to three different ecological tribes: Anatini, Aythyini, and Mergini. Parasitic nematodes (n=14,396) were found in the digestive tract of 813 out of 1,052 birds (77.3%), with the vast majority of nematodes (93.9%) found in the gizzard (n=7,326) and proventriculus (n=6,198). Nematodes isolated from these organs represented 21 species from six families: Amidostomatidae, Acuariidae, Tetrameridae, Dioctophymatidae, Ascarididae, and Anisakidae. The most prevalent were nematodes from the genus Amidostomoides (n=6,686 individuals; 49.4%), and the most dominant species was A. monodon (5,013 nematodes).