The field trips started each year in April, when adults of
large branchiopods were observed on previously known localities
(Gołdyn et al. 2007), and lasted till late September. The survey followed
the life cycle of particular species. As the occurrence of most
species is limited to the spring, the search for them was concentrated
in this period. The potential occurrence of late spring and
summer species was also controlled during successive months. In
the dry summer months (July, August) samplings were conducted
at least one week after heavy rainfall.