[Life cycle of Ixodes lividus Koch under the conditions in Leningrad Province].

Under conditions prevailing in the Leningrad region I. lividus has, in general, a one year life cycle. Having engorged on swallows overwintering larvae come off in burrows and in 24-26 days moult for nymphs. In a fortnight after 4-5 day feeding on nestlings the latter transform into imagos. After passing the stages of the postmoulting development (3-4 days), feeding on nestlings (5-7 days), rest (7-8 days) and oviposition (14-18 days) the females die. Larvae of a new generation appear in August-September. However, 2.8 to 6.5% of individuals in a population, due to late feeding of larvae or mortality of hosts, stop in their development at phases of imago and nymph and hibernate together with larvae. In an overwintering population they accounted for 3.4-5.0%.