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Mercury (Hg) contamination in piscivorous birds, especially methylmercury (MeHg), has been drawing much attention worldwide in regard to its bioaccumulation and biomagnification in food chains. In this study on Hg in the soft tissues of white-tailed eagles (n = 22) and ospreys (n = 2) from Poland, total Hg (THg) range was 0.15–47.6 while MeHg range was 0.11–8.05 mg kg−1 dry weight. In both species, median THg and MeHg concentrations were lower in the muscle and brain than in the liver and kidney. Median nephric residues were just under 3 and 5 mgTHg kg−1 or 0.9 and 3.7 mgMeHg kg−1 for white-tailed eagle and osprey, respectively. In Norwegian data from the 1970s and in our results, MeHg in the muscle of white-tailed eagle was ~60 % THg (%MeHg = MeHg/THg × 100), lower than in other piscivorous birds. A clear similarity in THg tissue levels was found between Polish and German populations of white-tailed eagles.

A new research project near Jericho in the Jordan Valley (Palestine) was launched on 10 September 2013, work continued until October 23rd 2013. Standard ornithological work and bird ringing work was conducted using mist nets situated in an oasis type habitat of Wadi Qelt surrounded by palm plantations. The field methods followed the SEEN (SE European Bird Migration Network) standards that include apart from ringing of captured birds, also several measurements (wing length, tail length, wing formula) and scores (fat load and body mass), as well as the studies on the directional preferences of migrants using round, flat orientation cages. Ornithological research was enhanced by parasitological studies analysing migratory birds (hosts) - helminths relations during migration period of the former. This was a part of complex studies covering the Middle East and north African ringing sites. Altogether 481 individuals of birds representing 59 species were ringed and about 50 were retrapped. The most interesting was relatively high share of Masked and Red-backed shrikes as well as good number of birds of local species as Dead Sea Sparrows and introduced Indian Silverbills.

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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.