The Event - The region - The Biological Station Lunz - Caddisfly research in Lunz

The event

The 17th International Symposium on Trichoptera comes back to Lunz am See, where the first Symposium was held in 1974. Earlier attempts to organise an International Symposium exclusively for Trichoptera were not successful. In the former Soviet Union, Sofia Grigorievna Lepneva had planned such a meeting, but she died before she could realise it. In the former Czechoslovakia, Karel Novák made a similar attempt but could not get the permission from his authorities. In 1974, Hans Malicky intended to meet fellow caddisfly workers of those days but could not travel all over the world to visit them all because of the lack of funding. So he invited them to a meeting in Lunz, and they came.

The region

Lunz am See is situated in the mountains of southern Lower Austria, and has a long history. The name Lunz is of Slavic origin which means that the settlement had already existed in the 6th Century. The original name may have been lomnica. The oldest name „liunze in montanis“ is found in a document by the bishop Wolfger of Passau in 1203. As a curiosity it may be mentioned that in the same document the existence of the famous Austrian medieval poet Walther von der Vogelweide was documented. His poems were well known, but this is the only document which says that he had really existed.

Lunz am See is situated in the district of Scheibbs, which is unusually well researched in a faunistic respect. Except for the research activities at the Biological Station Lunz, it is mainly the result of the monumental work of Franz Ressl, which is documented in five book volumes. Ressl was an amateur scientist who devoted himself in an admirable manner to research in the historical and natural sciences of his native land. He died in 2011, but his notebooks and records are not yet completely evaluated.


The Biological Station Lunz

The Biological Station Lunz was founded in that place because the site lies in a largely undisturbed landscape of mountains and lakes, and because the private owner of the area, Carl Kupelwieser, was fond of natural sciences. Later it turned out that this place is unique in the high diversity of its running waters. We know of no other site worldwide where a research institution has such a rich variation of streams of different types in a short distance. The photographs may give an impression. The Teichbach, which runs in the immediate vicinity of the building, shows extreme daily temperature fluctuations: in early spring it may have 2°C at 7 h in the morning, but 12°C at noon. The Schlöglbergbach on the other hand has a minor daily variation of not more than 3°C, and in winter it has over 0°C. The outlet of the lake may have up to 24°C during fine summer weather, but may quickly drop to 15°C after heavy rainfall, and in winter it is always close to 0°C. On the other hand, the Schreierbach has a constant temperature of 6,5°C all over the year, with a rare fluctuation between 5,5°C to 8°C.

The Biological Station Lunz had a long tradition in biological field research (see also here https://www.wcl.ac.at/index.php/en/about-us/history). This institution was founded in 1906 and was first intended to facilitate any zoological, botanical or similar field work. In those years scientists did not have cars to go quickly out of towns for a short research on plants or animals. The way to Lunz was long: first by railway, changing the train several times, and then a five kilometres walk from the railway station to the Biological Station at the eastern edge of the lake, with all the necessary equipment in the rucksack. Therefore, the usual stay of researchers was for weeks of even months. The studies were performed within walking distance of the building, and usually one could meet fellow workers of related sciences from all over the scientific world. It was a unique opportunity to sit together during long coffee breaks and endless discussions and to start co-operation on joint field projects: geology, climate and weather research, study of insects, lichens, mosses, ornithology and the like. One remarkable result of this co-operations was the detection of a site (Grünloch, a large Doline, which is a karstic depression) high in the mountains where in winter, temperatures lower than –50°C were recorded. Newspaper people with a need for sensation made Lunz itself to be the „European coldness pole“, an opinion which now is still widespread among people. In reality, Lunz has a rather cool climate with high rainfalls like many other sites at the northern slope of the Alps.

In 1924, Franz Ruttner was called from Prague to join the Biological Station. A short time later he became its director until his retirement. He died in 1961. He was a unique and dominant personality. He had originally studied aquatic organisms, so the main work of the Station was focussed on the newly established scientific branch called Limnology (of which he was one of its founders). In these days, limnology was understood as the study of lakes. Running waters were “detected” by limnologists much later. Franz Ruttner was one of the leaders of the famous Sunda Expedition to Indonesia in the years 1928 to 1929, which created the fundamentals of tropical limnology, and the results of which were published in many volumes of the Archiv für Hydrobiologie.

The Biological Station Lunz was closed in 2003. The freshwater studies are however continued by a newly founded institution called WasserCluster Lunz (https://www.wcl.ac.at/index.php/en/). The WasserCluster Lunz is an inter-university centre for freshwater ecosystem research with a broad focus: research targets include nutrient and carbon dynamics, plankton ecology, trophic ecology and freshwater biodiversity.

Caddisfly research in Lunz

Among the visitors of the Biological Station who worked over a longer time period, were amateur scientists who used the summer holidays for their studies. One of them was Hans Krawany, a teacher from St. Pölten. He started to study the caddisflies in 1925, mainly the larvae, in the streams in and around Lunz. He found important connections between the composition of the fauna and the water temperature. This pioneer work (Krawany 1928 - 1933) shows clearly the situation of the knowledge on Trichoptera in those years. In later years, Gertrud Pleskot and Ernst Pomeisl continued this study in Lunz. Elisabeth Danecker studied the hygropetric fauna including Tinodes zelleri and two Stactobia species.

From 1969 onwards, Hans Malicky had the opportunity to continue these studies. He came as a zoologist to the Biological Station Lunz of the Austrian Academy of Sciences and started with the study of running water ecology and, in particular, with the taxonomy and biology of caddisflies. He studied the water temperatures of the streams over a whole year and improved the identification of species by extending to the adult caddisflies. More tasks followed, and the result was a better taxonomic knowledge of the adult Trichoptera of the whole of Europe. The Atlas of European Trichoptera was published in 1983, and its second edition in 2004. More than 30 streams in the immediate surrounding of Lunz were studied with emergence traps, usually over one-year periods, but the Schreierbach, the Teichbach and the upper part of the Kothbergbach over eight years, with the assistance of Erich Lanzenberger. At several sites, light traps helped to complete the survey of caddisflies. The caddisflies in the samples were immediately identified, and other trapped insects were given to fellow workers in other institutions for further study. The resulting data may be found in the Zobodat database (www.zobodat.at). As daylength plays an important role in the phenology of plants and animals, a field experiment was performed at the Schreierbach, a stream with a constant water temperature of 6,5°C over all the year. Lamps were placed over the stream to supply the bottom with daily 18 hours of light over two years. In the Kothbergbach, several types of construction of emergence traps were compared over a period of eight years. More information on these streams, including the lists of species, may be found in the book “Lebensräume von Köcherfliegen” (Malicky 2014). More examples of streams with their caddisflies over the whole of Europe are found in this book, as well as examples of tropical streams.