Franz Rubel

This atlas provides updated maps based on georeferenced tick locations of 22 species endemic in Germany, three regularly imported tick species and one species that was previously frequently imported into Germany. Thus, the current version of the atlas of ticks in Germany contains distribution maps for a total of 26 tick species with the following numbers of newly georeferenced tick locations: 1 Argas reflexus , 10 Carios vespertilionis , 3 Dermacentor marginatus , 53 Dermacentor reticulatus , 10 Haemaphysalis concinna , 7 Haemaphysalis punctata , 2 Hyalomma aegyptium , 111 Hyalomma marginatum , 39 Hyalomma rufipes , 2 Ixodes arboricola , 2 Ixodes crenulatus (syn. Ixodes canisuga ), 27 Ixodes frontalis , 43 Ixodes hexagonus , 6 Ixodes lividus , 271 Ixodes ricinus , 1 Ixodes rugicollis , 5 Ixodes trianguliceps , 1 Ixodes uriae , 2 Ixodes ventalloi , 1 Ornithodoros maritimus , and 32 Rhipicephalus sanguineus sensu lato. Ixodes inopinatus has been removed from the previously included species list because more recent studies have shown that these were misidentifications. The rabbit tick I. ventalloi , the argasid seabird tick O. maritimus and the formerly frequently imported tortoise tick Hy. aegyptium , however, have been included in the current atlas of ticks in Germany. In total, the digital dataset available for Germany is updated by 629 new tick locations. These records increase the number of tick species mapped in the federal state Saxony by six, those in Hamburg by five, those in Brandenburg by four, those in Schleswig-Holstein by three, those in Baden-Wuerttemberg, Bavaria and Thuringia by two each, and those in Bremen, Northrhine-Westphalia, Rhineland Palatinate and Saarland by one each. Of the 26 tick species ever detected in Germany, 21 were observed in the period 2001–present. Thus, the second data update of the atlas of ticks in Germany provides the most comprehensive digital dataset to date on the distribution of tick species in Germany.

The nidicolous tick Ixodes laguri is a nest-dwelling parasite of small mammals that mainly infest rodents of the families Cricetidae, Gliridae, Muridae and Sciuridae. There is no proven vectorial role for I. laguri , although it is suggested that it is a vector of Francisella tularensis . In this study, a first map depicting the entire geographical distribution of I. laguri based on geo-referenced locations is presented. For this purpose, a digital data set of 141 georeferenced locations from 16 countries was compiled. Particular attention is paid to the description of the westernmost record of I. laguri in the city of Vienna, Austria. There, I. laguri is specifically associated with its main hosts, the critically endangered European hamster ( Cricetus cricetus ) and the European ground squirrel ( Spermophilus citellus ). These two host species have also been mapped in the present paper to estimate the potential distribution of I. laguri in the Vienna metropolitan region. The range of I. laguri extends between 16–108° E and 38–54° N, i.e. from Vienna in the east of Austria to Ulaanbaatar, the capital of Mongolia. In contrast to tick species that are expanding their range and are also becoming more abundant as a result of global warming, I. laguri has become increasingly rare through-out its range. However, I. laguri is not threatened by climate change, but by anthropogenic influences on its hosts and their habitats, which are typically open grasslands and steppes. Rural habitats are threatened by the intensification of agriculture and semi-urban habitats are increasingly being destroyed by urban development.

Although European hamsters and European ground squirrels are listed as critically endangered on the IUCN Red List of Threatened Species , their habitats are becoming increasingly smaller due to the rapid expansion of the city of Vienna. The distribution of both species over the period 2000–2023 was documented by compiling a map based on georeferenced data from scientific monitoring and citizen science collections. Based on this, the population sizes in the metropolitan area of Vienna were estimated at 4000 hamsters and 16000 ground squirrels. An overview map was also created for each of the two species, which contains the names of the most important local occurrences. Satellite images were used to document populations that became extinct during the study period or in which animals lost large parts of their traditional habitat due to new urban development. This is considered particularly important in terms of conservation, as future generations would otherwise see the absence of wildlife in cities as normal, an effect known as shifting baseline syndrome. The Court of Justice of the European Union clarified key concepts for strict species protection. These also include eco-offsetting, i.e. creating habitats to replace ones lost to development, which was already applied before a recent construction project was implemented. On the occasion of this project, the application of eco-offsetting to protect the local ground squirrel population was documented and critically discussed.

The first data update of the atlas of ticks in Germany published in 2021 is presented here. This atlas provides maps based on georeferenced tick locations of 21 species endemic in Germany as well as three tick species that are regularly imported to Germany. The data update includes the following numbers of newly georeferenced tick locations: 17Argas reflexus, 79Carios vespertilionis, 2Dermacentor marginatus, 43Dermacentor reticulatus, 4Haemaphysalis concinna, 3Haemaphysalis punctata, 3Hyalomma rufipes, 3Ixodes apronophorus, 9Ixodes arboricola, 1Ixodes ariadnae, 30Ixodes canisuga, 3Ixodes frontalis, 80Ixodes hexagonus, 3Ixodes lividus, 497Ixodes ricinus/inopinatus, 1Ixodes rugicollis, 17Ixodes trianguliceps, 14Ixodes vespertilionis, and 45Rhipicephalus sanguineussensu lato. Old and new tick findings were mapped, such as the northernmost occurrence ofD. marginatusin Germany observed in 2021, but also the historical records from the first descriptions ofI. apronophorusandI. arboricola, which were georeferenced here for the first time. The digital dataset of tick locations available for Germany is supplemented by 854 new tick locations. These records increase the number of tick species mapped in the federal states Bavaria, Brandenburg and Mecklenburg Western Pomerania by five each, those in Berlin and Schleswig-Holstein by four each, those in Hamburg by three, those in Baden-Wuerttemberg, Bremen, Lower Saxony, Northrhine-Westphalia, Rhineland Palatinate and Thuringia by two each, and those in Hesse, Saxony and Saxony-Anhalt by one each. Thus, the first data update of the tick atlas in Germany and the underlying digital dataset significantly improve our knowledge of the distribution of these tick species and helps to investigate the effects of climate change and habitat changes on them.

A first compilation of georeferenced tick locations in Austria and South Tyrol, Italy, is presented here. This allows the tick fauna to be examined in the various climatic regions of the European Alps. The dataset comprises 424 tick locations of Austria and 48 tick locations of South Tyrol, which were digitized from literature and visualized in the form of geographical maps. The tick fauna of Austria includes two species of Argasidae in the genera Argas and Carios and 15 species of Ixodidae in the genera Dermacentor, Haemaphysalis, and Ixodes, altogether 17 tick species. In addition, two species of Ixodidae in the genera Hyalomma (each spring imported by migratory birds) and Rhipicephalus (occasionally imported by dogs returning from abroad with their owners) are included in the tick atlas. Of these, the georeferenced locations of 18 tick species are depicted in maps. The occurrence of the one remaining tick species, Ixodes inopinatus, is given at the level of the federal states. The first Austrian distribution map of the long-legged bat tick Ixodes vespertilionis, which was reported from 21 caves, deserves special mention. The most common and widespread tick species is Ixodes ricinus, with records in all nine federal states of Austria, followed by Ixodes canisuga, Ixodes hexagonus, and I. vespertilionis in six federal states each. Haemaphysalis concinna and Dermacentor reticulatus are only endemic in the eastern plains, while Dermacentor marginatus only occurs in the west, in the Tyrolean Alpine valleys. Eight tick species were reported from South Tyrol, Italy. There, the most frequently flagged tick from the vegetation is also I. ricinus, while D. marginatus and Haemaphysalis punctata are often collected from sheep. The locations are shown together with those from North and East Tyrol on a separate Tyrol map. The tick atlas in Austria and South Tyrol as well as the underlying digital dataset in the supplement contribute to the closing of data gaps in global distribution maps of ticks and improve the data basis for new species distribution models.

An updated and increased compilation of georeferenced tick locations in Germany is presented here. This data collection extends the dataset published some years ago by another 1448 new tick locations, 900 locations of which were digitized from literature and 548 locations are published here for the first time. This means that a total of 3492 georeferenced tick locations is now available for Germany. The tick fauna of Germany includes two species of Argasidae in the genera Argas and Carios and 19 species of Ixodidae in the genera Dermacentor, Haemaphysalis, and Ixodes, altogether 21 tick species. In addition, three species of Ixodidae in the genera Hyalomma (each spring imported by migratory birds) and Rhipicephalus (occasionally imported by dogs returning from abroad with their owners) are included in the tick atlas. Of these, the georeferenced locations of 23 tick species are depicted in maps. The occurrence of the one remaining tick species, the recently described Ixodes inopinatus, is given at the level of the federal states. The most common and widespread tick species is Ixodes ricinus, with records in all 16 federal states. With the exception of Hamburg, Dermacentor reticulatus was also found in all federal states. The occurrence of the ixodid ticks Ixodes canisuga, Ixodes frontalis, Ixodes hexagonus and I. inopinatus were documented in at least 11 federal states each. The two mentioned argasid tick species were also documented in numerous federal states, the pigeon tick Argas reflexus in 11 and the bat tick Carios vespertilionis in seven federal states. The atlas of ticks in Germany and the underlying digital dataset in the supplement can be used to improve global tick maps or to study the effects of climate change and habitat alteration on the distribution of tick species.