The effect of peatland drainage and restoration on Odonata species richness and abundance.

BACKGROUND: Restoration aims at reversing the trend of habitat degradation, the major threat to biodiversity. In Finland, more than half of the original peatland area has been drained, and during recent years, restoration of some of the drained peatlands has been accomplished. Short-term effects of the restoration on peatland hydrology, chemistry and vegetation are promising but little is known about how other species groups apart from vascular plants and bryophytes respond to restoration efforts. RESULTS: Here, we studied how abundance and species richness of Odonata (dragonflies and damselflies) respond to restoration. We sampled larvae in three sites (restored, drained, pristine) on each of 12 different study areas. We sampled Odonata larvae before restoration (n = 12), during the first (n = 10) and the third (n = 7) year after restoration and used generalized linear mixed models to analyze the effect of restoration. Drained sites had lower abundance and species richness than pristine sites. During the third year after restoration both abundance and species richness had risen in restored sites. CONCLUSIONS: Our results show that Odonata suffer from drainage, but seem to benefit from peatland restoration and are able to colonize newly formed water pools already within three years after restoration.

Checklist of the cecidomyiidae (Diptera) of Finland.

A list of the 356 species of Cecidomyiidae (Diptera) recorded from Finland is presented, which comprises 6 Lestremiinae, 156 Micromyinae, 16 Winnertziinae, 69 Porricondylinae, and 109 Cecidomyiinae. The faunistic knowledge of Finnish Winnertziinae, Porricondylinae and Cecidomyiinae is regarded as particularly poor. Based on species numbers known from other countries in Europe, a conservative estimate is 700-800 species of Cecidomyiidae actually occurring in Finland.

Recent noteworthy findings of fungus gnats from Finland and northwestern Russia (Diptera: Ditomyiidae, Keroplatidae, Bolitophilidae and Mycetophilidae).

New faunistic data on fungus gnats (Diptera: Sciaroidea excluding Sciaridae) from Finland and NW Russia (Karelia and Murmansk Region) are presented. A total of 64 and 34 species are reported for the first time form Finland and Russian Karelia, respectively. Nine of the species are also new for the European fauna: Mycomyashewelli Väisänen, 1984, Mycomyathula Väisänen, 1984, Acnemiatrifida Zaitzev, 1982, Coelosiagracilis Johannsen, 1912, Orfeliakrivosheinae Zaitzev, 1994, Mycetophilabiformis Maximova, 2002, Mycetophilamonstera Maximova, 2002, Mycetophilauschaica Subbotina & Maximova, 2011 and Trichontapalustris Maximova, 2002.

Local extinction of dragonfly and damselfly populations in low- and high-quality habitat patches.

Understanding the risk of extinction of a single population is an important problem in both theoretical and applied ecology. Local extinction risk depends on several factors, including population size, demographic or environmental stochasticity, natural catastrophe, or the loss of genetic diversity. The probability of local extinction may also be higher in low-quality sink habitats than in high-quality source habitats. We tested this hypothesis by comparing local extinction rates of 15 species of Odonata (dragonflies and damselflies) between 1930-1975 and 1995-2003 in central Finland. Local extinction rates were higher in low-quality than in high-quality habitats. Nevertheless, for the three most common species there were no differences in extinction rates between low- and high-quality habitats. Our results suggest that a good understanding of habitat quality is crucial for the conservation of species in heterogeneous landscapes.