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Work within a national programme for the reinstatement of the Peregrine Falcon Falco peregrinus peregrinus saw reintroduction attempts made in 1993 and 1994 in S Poland's Pieniny National Park. Use was made of an artificial nest resembling the rocky niches favoured by the species, but equipped with a feeding pipe and remotely-controlled cover via which the birds were released. Three males about 42 days old were provided by a German breeder, placed in the nest on June 16th 1993, and released 10 days later. Flying efficiency was seen to have improved within 2 weeks of release, and interest in delivered food had been lost completely by the 32nd day. Between March and June of 1994, two of the three reintroduced birds were noted in the release area, and even on the artificial nest from which two females were later released (after adaptation) on July 6th 1994. This release matched that of 1993 in achieving a successful first stage (to the time of independent hunting).
Metal pollution can drastically decrease the diversity of species of many groups of terrestrial invertebrates. Well-performed reclamation may prevent the loss of species diversity. In this study, we used multivariable statistical methods to describe the species diversity of carabids and ants originating from two zinc-lead mine tailing ponds under different degrees of reclamation practices. Although the species diversity of carabids and ants in both study sites and in both seasons was relatively high, the investigated communities were dominated by one numerous species. Discriminant analysis indicated that the difference between study sites is due to the high number of carabid species found in the comprehensively reclaimed site and the high abundance of several species of ants found in the partially reclaimed site. The most striking difference in species composition between the study sites was the contribution of forest species. The comprehensively reclaimed site maintains more species of forest carabids but fewer forest species of ants in comparison to the partially reclaimed one.
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A total of 70 pigeons from Cracow area was examined and the representation of bird lice (Mallophaga) infesting them estimated. Mostly the populations of two dominant species: Columbicola columbae columbae (L.) and Campanulotes bidentatus compar (Burm.) were assessed. 47% of birds inspected had less than 100 specimens of Mallophaga, although the highest infested one had 900 specimens. Sex and age of pigeons did not influence the number of bird lice present, and only weak health condition of individuals allowed higher infestation. The sex structure of ectoparasites was balanced, with a slightly higher number of females during the year of study. The highest number of bird lice was detected in autunm and the larvae definitely predominated then, as well. Similar tendency was observed in C. c. columbae populations. The course of age dynamie of C. b. compar was somewhat different, having the peak in July, and the imago stage dominated in this species. The populations of in C. c. columbae showed developmental signs, whereas the population structures of C. b. compar gave evidence of their regression.
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