The structure and dynamics of a water beetle community in a ...

Fig. 10 – Seasonal changes of the flight activity of dominant species of the three main taxonomical groups in
2002–2006. Running daily means (for 6 consecutive samples = two weeks) is plotted for every species. Arrows
denote maximum numbers of specimens captured per night. Day given as ordinal date.
Relative species composition undergoes significant changes during the season (Table
3 and Fig. 11). The changes vary significantly among years only when the whole assemblage
is considered and remain consistent within the families despite subtle differences apparent in
Fig. 10. The Hydrophiloidea clearly dominate in summer, while the Dytiscidae have two
separate peaks in late spring and late summer, and the Scirtidae dominate in spring and
decline over the season (Fig. 12 and Table 4). The mean relative abundance of individual
groups and dominant species also changes among years (Table 5).
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