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The authors present both historical and current lists of dragonfly species occuring in the Upper Silesia, based on the analyses of documented materials as well as their own terrain research carried during recent years.
During inventory-making of dragonflies in the Silesian voivodeship 13 localities outside the area of nature reserves were found at which 15 dragonfly species belonging to protected or rare animal species occurred. Only one of the sites seems to be safe from human activities or natural succession. The remaining ones need continuous monitoring, some of them should be actively protected.
While the registration of dragonflies on man-made reservoirs of the Silesian Region took place, in 2006 there were recorded nu- merous males and less numerous females of Aeshna affinis. Single individuals have been reported in 1939 in Gwoździany and in 1966 in Ustroń. Since its last record Aeshna affi­nis has been noted again in 2005 in an old river bed of the River Odra River in Lasaki. It has been recorded on seven new sites in the next year. Most of those new sites were smali sinkhole ponds created by coal-mining. What is morę Aeshna affinis was recorded on a few natural sites too. While on natural sites there were 2-4 specimens recorded, on anthropogenic water bodies there were usu- ally about 20 individuals. Creating tandems indicated making attempts to inhabit anth­ropogenic water bodies by this species. The­re was another ąuite rare and stenothermic species - Crocothemis erythraea recorded on two sites together with Aeshna affinis. This species has been observed sińce 2002 in Odra River Valley, near the Southern bor- der of Silesian Region with Czech Republic. Nevertheless it was recorded for the first time in sinkhole ponds in 2006.
The inventory of dragon*ies was con- ducted on 244 sites in the Silesian Province in 2002–2012. The total number of 34 sites of Leucorrhinia pectoralis was found. This species is protected by law in Poland and a priority for the European program for hab- itats protection “Nature 2000”. The compar- ison of the present with historical data from the years 1958–1965 showed that L. pectoralis vanishes from peat bogs in this region. The reason for this situation is deteriorating condition of these habitats, mainly because of their desiccation and industrial pollution. It was noted however, that the species is present in a relatively high number on for- est sinkhole ponds emerging over coal ex- ploitation areas in the central, industrialized part of the province. Approximately 20% of investigated sinkholes presented conditions favorable for the reproduction and develop- ment of L. pectoralis. However, these habi- tats are unstable and do not sustain perma- nent presence of the species.
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