Forschen und Sammeln.

The checklist of the habitats of South Tyrol has become an important tool in the biodiversity documentation of South Tyrol as well as in nature conservation practice. 15 years of application experience with the first edition of the list made it necessary to incorporate new findings and requirements into it. The present second edition builds directly on the first one and keeps the hierarchical structure and the habitat coding basically unchanged. Changes compared to the first edition primarily concern the addition of new habitats, especially in the lower hierarchical levels, but also adjustments in content. The latter prove to be particularly useful for a possible crosslink to Natura 2000 habitats – a declared goal of the working group.
The second edition now includes 340 habitats of all hierarchy levels, which is 77 more than in the first edition. One habitat, the oak-elm-ash hardwood forests, has been removed from the list because there is no evidence of its existence in South Tyrol so far and in order to avoid erroneous assignments to this habitat.

The state of knowledge of the genus Alchemilla in South Tyrol was highly incomplete until the end of the 20th century. This was true for the species inventory as well as for the distribution of individual species. From the 1980s onwards, the first comprehensive distribution data were obtained in the course of floristic mapping by the Botanical Institute of the University of Vienna, and the species inventory grew to 41 species. Within the framework of a project initiated and coordinated by the Museum of Nature South Tyrol, an area-wide survey (grid mapping) of the Alchemilla species of South
Tyrol was carried out in the period 2010–2022, accompanied by the establishment of a comprehensive and complete Alchemilla herbarium. The results of the intensive field surveys, revision activities and historical research are depicted in the present monograph: Each of the now 50 species documented in South Tyrol is presented individually with South Tyrol specific information on ecology and distribution, with informative photos of habit and leaf forms.
The following species, listed in the literature for South Tyrol, are classified as doubtful or erroneous: Alchemilla acutidens, A. demissa, A. inconcinna, A. kerneri, A. obscura, A. trunciloba.
A detailed identification key of all so far ascertained species will provide a reliable aid for the further study of the genus Alchemilla in South Tyrol.

Climate warming can be regarded as the main factor for changes occurring in alpine ecosystems. As high elevation species in the Alps are considered to be particularly sensitive to climate change, long term monitoring projects are important to determine amount and direction of biodiversity changes. This study extended the monitoring of the GLORIA sites in the Dolomites, started in 2001. According to previous studies, eastern and southern aspects are those with the most notable changes. We focused, therefore, on the identification and distribution of plant communities and the phytosociological differences between the summits and their southern slopes from the treeline upward. Ecological differences should be unravelled by the analysis of LandoLt indicator values temperature and soil nutrients as well as by the competitive and non-competitive species. Four plant communities were identified on the south-facing slopes. Three of them were alpine grassland communities, while scree vegetation was only found on the higher plots of the highest summit. At the summits, additionally, two pioneer grassland communities were identified. This study gives further evidences of the ongoing thermophilisation at the summits. From our results it seems that on one summit changes in the plant communities are more likely to happen in the near future, while on the other two summits topographical barriers should prevent imminent changes.

In the framework of the ongoing project Biodiversity Monitoring South Tyrol a hitherto unknown orthoptera species was newly recorded for the fauna of South Tyrol: Pezotettix giornae was found in summer and autumn 2022 close to Tramin/Termeno in the South of South Tyrol. The distribution of the species, its chorological status and a possible threat are shortly discussed.

The freshwater bivalves Unionidae are in dramatic decline globally. Due to wide shell variability, only the genus can be determined by traditional morphological methods, with genetic analyses being required for species identification. From November 2018 to October 2020 four freshwater bodies in the Province of Bolzano/Bozen (Italy) (Small Lake and Large Lake of Monticolo/Montiggl, Lake Caldaro/ Kaltern, and its main emissary Fossa Grande di Caldaro/Großer Kalterer Graben) have been explored to collect unionid bivalves by hand and scuba diving. Unionid presence, bathymetric distribution, biometric characteristics, and attachment of invasive allochthonous zebra mussel (Dreissena polymorpha) were detected.
Molecular barcoding analyses (COI) on foot snips from 25 specimens (19 Anodonta and 6 Unio) confirmed the presence of four native species: Anodonta anatina, A. cygnea, A. exulcerata, and Unio elongatulus. Most Anodonta specimens from both Small (78 %) and Large Lake of Monticolo (60 %) were parasitized by Dreissena polymorpha in numbers ranging from 1 to 81 per individual. The biomass of D. polymorpha amounted up to 41 % of Anodonta’s weight. D. polymorpha was not found in Lake Caldaro/Kaltern and its emissary Fossa Grande di Caldaro/Großer Kalterer Graben.

Fish stocking is a common practice to support endangered fish species or to promote local fisheries, also in South Tyrol, but current species protection and the maintenance of functioning aquatic ecosystems require sustainable management and stocking activity. While tocking measures in South Tyrol’s waters have been documented for decades, cross-water and rovince-wide stocking dynamics and priorities or shifts in population densities of stocked fish species have not yet been examined. In analyzing stocking and fish survey data from the local Hunting and Fishing Office from the last 20 (fish surveys) and 30 (stocking) years we demonstrate a general decrease of fish stocking throughout the province and identify past and present prioritized fish species. The non-native Salmo trutta and Oncorhynchus mykiss have been and still are the most stocked fish in South Tyrol (46 ±3 % and 37 ±4 % of the total stocked biomass) with little differences between catchments, while the native Salmo marmoratus was stocked much less (15 ±5 %) and has even been replaced by stocking eggs and juveniles within the last years. The minor stocking of Salvelinus fontinalis (4 ±1 %) was stopped. Similarly, comparisons of multiple fished populations reveal comparable patterns with strong positive trends for the most stocked Oncorhynchus mykiss (+7.1 %), while densities of sparsely stocked Salvelinus fontinalis decreased sharply (–7 %). Also, the native and protected Salmo marmoratus shows slight decreases over the last decades, which is why scientifically based conservation measures (e.g., egg stocking) and ongoing province-wide monitoring of population trends remain necessary.

Here we report four spider findings that are new for the Province of South Tyrol (northern Italy), with two of them being new for Italy. All spider species were found on extensively grazed dry pastures located in the inner-alpine dry Vinschgau valley and in or close to the Italian LT(S)ER area „Val Mazia/Muntatschinig“ (LTER_EU_IT_097).
The jumping spider Pellenes lapponicus (Sundevall, 1833) (Salticidae) and the crab spider Psammitis bonneti (Denis, 1938), both new to South Tyrol, were found on alpine dry grasslands at 2500 m a.s.l. above the localities of Schluderns/Sluderno and Obertels/Tels di Sopra (Tanas, Laas/Lasa).
The velvet spider Eresus sandaliatus (Martini & Goeze, 1778) (Eresidae) was also found on alpine dry grasslands at 2500 m on the adjacent crest above the localities of Muntatschinig and Matsch (both Mals/Malles Venosta). The yellow sac spider Cheiracanthium campestre Lohmander, 1944 (Cheiracanthiidae) was found in sub-alpine dry grasslands at 1500 m close to Planeil and Muntatschinig (both Mals/Malles Venosta). These two spiders are new recordings for both South Tyrol and Italy.

There are few studies on ground-dwelling invertebrates from alpine ecosystems, often with only one or a few samplings per growing season. However, to get a most comprehensive picture of the faunal community present, samplings throughout an entire season are needed. Here we present data on ground-dwelling macro-invertebrate communities from four characteristic alpine habitats (i.e., pasture, dwarf shrub heath, grassland, and fragmented grassland) along a short elevation gradient. They were monitored continuously over almost an entire growing season (June to October) using pitfall traps.
We found considerable differences between the four habitat types, with the pasture having the lowest abundances (i.e., activity densities as individuals per sampling day). At the other three sites, biodiversity indices (i.e., Shannon and Evenness) increased with elevation, while the activity densities of the main taxa Araneae, Myriapoda and Coleoptera decreased; they showed a peak activity in mid-July to mid-August. The faunal communities, despite sharing many families among habitat types, showed a clear separation of three groups in the ordination plot (CCA), with the pasture and grassland harbouring similar communities and being well separated from the ones of the dwarf shrub heath and the fragmented grassland.
In this study we found distinct ground-dwelling macro-invertebrate communities in four characteristic alpine habitats, despite their spatial proximity. We found the vegetation i.e., here plant life-forms as proxy) being a strong driver shaping faunal communities. Additionally, the quite intensive grazing activities on the pasture might have negative impact on the invertebrates, while low/no grazing at the more natural higher plots (i.e., grassland and fragments) and a high habitat heterogeneity (at the fragmented grasslands) might be reflected in high numbers of abundances and biodiversity indices. Our study underlines the importance of assessing alpine soil fauna by performing many samplings throughout a growing season to depict most complete faunal communities.

The paleontological collection of Georg Gasser gives important insights in the fossiliferous sites of the 19th and 20th century, and the fossils collected and studied during that time interval. With about 90% the invertebrates represent the biggest part of the paleozoological specimens. All major groups are represented, although there is a clear predominance of molluscs reflecting Gasser’s particular predilection for these animals. Although 45 % of the finds suffer a lack of information on the labels. The collections give us nonetheless a picture of the main areas of provenance for the fossils and an hint on Gasser’s compositional idea regarding the collection. A close connection between Gasser and the German-speaking areas in Europe as primary source of the specimens is evident, with only rare exotic exceptions represented by some localities in America, Africa or in the Atlantic Ocean. This work is based on a preliminary study, realized with the aim of promoting insights and favor the divulgation of the historical content of this paleontological heritage.