Seasonal changes in numbers of fleas [Siphonaptera] in nests of the house sparrow [Passer domesticus] and tree sparrow [P.montanus] in Warsaw surroundings [Poland]

In the commune of Łomianki near Warsaw, Poland (52°20'N, 20°50 'E), 12 samples of at least 19 nests we collected from wooden nest boxes between 1995-1999. The samples were unevenly distributed among months, but in total they represented each month of the year. In total 386 nests were analysed, including 283 of the tree sparrow (Passer montanus), 30 of the house sparrow (P. domesticus) and 73 nests of the genus Passer, but unidentified species. Using the Tullgren apparatus, 7692 imago fleas of 8 species were extracted from these nests. Only Ceratophyllus gallinae and C. fringillae were sufficiently abundant to analyse changes in their numbers. The number of C. gallinae was about 3.1 times higher than of C. fringillae. The abundance, prevalence and dominance of the two flea species were analysed in the annual cycle. Adult forms of the two flea species were leasl abundant in nests in April. Their numbers increased between May and July, slightly decreased in August and rapidly increased in September and October, reaching the maxima in all the indices, except for the dominance in the community of nest fauna. C. fringillae dominated in March and C. gallinae in September. In the winter months, adult C. gallinae occurred in relatively large numbers. In the nests of tree sparrow, fleas probably produced at least two and possible even three generations.