Seasonal changes of quantitative distribution and some ecological features of Abra ovata (Mollusca, Bivalvia) near the midwestern coast of the Caspian Sea
Zoologicheskii Zhurnal 56(8): 1150-1160
ISSN/ISBN: 0044-5134 Accession: 006371765
A. ovata Phill. introduced in the Caspian from the Azov Sea spread widely near the western coast of the middle Caspian by 1959, and its range embraced all the costal zone of the middle and south Caspian by the beginning of 1962. Judging by the appearance of mollusks < 2 mm in size in the benthic samples, the settling of larvae in different parts of the region occurs at different times and is due to the temperature regime (increase of 8-11.degree. C in spring and decrease of 8-11.degree. C in autumn). Marked seasonal changes are observed the quantitative distribution of mollusks which are determined, mainly, by the distribution of sturgeons.