Tytuł pozycji:
Experimental studies of the exploitation and overcrowding of a natural population of the Roman snail, Helix pomatia L.
Strony 401-421 : ilustracje ; 24 cm
Streszczenie w języku polskim
Bibliografia na stronach 420-421
Surveys of the Roman snails were carried out in the Ojców National Park, at three experimental sites. In a population that had been rejuvenated due to exploitation a reduction in fecundity was found; with an increased mobility of individuals this meant a lack of partners for mating. Food supplies and migrations are factors determining the density. An experimental increase in density caused by man accelerates the mobility and reduces the fecundity. Emigration was more often found among introduced individuals, differing in size from the native ones. On the basis of the annual shell increments it has been established that the growth of an individual usually continues for 4 years, often still after the attainment of sexual maturity, whereas the body size of individuals from local habitats varies as a result of selection.
Bibliographical references (pages 420-421)
Abstract in Polish
Pages 401-421 : illustrations ; 24 cm