Seasonal and age-specific dynamics of the Griffon Vulture’s home range and movements in the Eastern Rhodopes

The spatial ecology of the Eurasian Griffon Vulture (Gyps fulvus) has been a subject of scientific interest for long due to its conservation status, critical ecosystem role, gregarious lifestyle and complex foraging behavior. The trans-border Eastern Rhodope Mountain in Bulgaria and Greece holds an increasing population of the species and one of the largest on the Balkan Peninsula. We used high-frequency GPS data from 13 Griffon Vultures from this population to study their movements, home range size and its seasonal or age specific dynamics. The overall foraging home range (95% kernel) was 3,204 km2 and the core area of activity (50% kernel) was 256.5 km2. We found high seasonal variation of the home range size. Vultures were foraging over larger areas in the summer and spring but their activity was limited to four times smaller areas in winter. We found no age specific variation in the home range sizes but the non-adult vultures showed tendency to conduct exploratory movements far from the breeding colony. Our results can be used for planning conservation efforts in the areas of high importance for the species.

Fossil gastropods Campanile lachesis Bayan, 1870 from the upper Eocene of the Eastern Rhodopes (Bulgaria)

The subject of this study is the description of eight specimens of fossil gastropods Campanile lachesis Bayan, 1870, family Campanilidae, from the fund of the Regional Museum of History in Kardzhali. They were found in the area of the village of Gorna Krepost, Kardzhali Municipality, at the eastern foot of the Archeological Complex Perperikon, in the upper Eocene (Priabonian) limestone layers of the so-called Beli Plast Rhyodacite Complex. The paleoecological traits of the present fauna give ground to infer that this was a very shallow reefal environment with a rocky substrate sandy bottom, overgrown with algae, and the water was warm, with normal salinity.

Comments on the paper of Peter Marchev et al. “Early Oligocene supereruption in SE Europe outlined by 33.3 Ma U-Pb ages for Lemnos tuff and correlation with regional ash deposits” – C. R. Acad. Bulg. Sci., 74, 3, 2021, 396–405.

These critical notes challenge the interpretation of the authors of the article that the volcanic source of the described tuffs on the island of Lemnos (Greece) is the source of Dazhdovnitsa tuffs (beginning of the Oligocene) and that it is located in the Bororvitsa caldera, Eastern Rhodopes. However, there are large regions between this caldera and the island of Lemnos (e.g. between the villages of Podkova and Dobromirtsi in the southern part of the Eastern Rhodopes), where no pyroclastic layers are found at the base of the Oligocene section, corresponding to the stratigraphic position of the Dazhdovnitsa tuffs. It has been suggested that the volcanic source of Lemnos tuffs may be located in the Kalotiko volcanic region, situated essentially in Northern Greece. It has a multi-phase Rupelian volcanic activity, but it is not dated in detail.

Geochemistry of bentonite clays from the Eastern Rhodopes (SE Bulgaria): preliminary results

In this work we report data from LA-ICP-MS analyses of 7 bentonite samples from the Eastern Rhodopes as three of the samples come from two bentonite deposits – Zlatna Livada and Propast-Dobrovolets. The obtained results show no significant accumulation of trace elements in the studied samples. Their overall chemical composition is strongly influenced by the volcanic glass chemistry, the presence and abundance of magmatic minerals and lithic clasts and to lesser extent by secondary authigenic mineral associations. Respectively, their trace element signature is similar to that of the unaltered extension-related orogenic volcanic rocks in the Eastern Rhodopes. No correlation between any of the trace elements measured and the relative montmorillonite abundance (in samples A-ZL and I-PD) have been established. Nevertheless, these data complete the knowledge of bentonite clays from the Eastern Rhodopes; they can shed more light on the connection between volcanic precursors and alteration products and can provide deeper insight into the process of glass transformation.

Spread of the invasive pathogen Lecanosticta acicola on species of Pinus in Bulgaria

The brown spot needle blight, caused by the fungal pathogen Lecanosticta acicola, has been the most serious and damaging disease on needles of Pinus spp. in recent years. In Bulgaria, the pathogen was reported for the first time in 2017 in a generative plantation of Pinus sylvestris in the region of the State Forestry Ardino, the Eastern Rhodopes. The newly- established invasive pathogen is considered highly adaptable to new hosts and environmental conditions. The life cycle and symptoms of the disease strongly suggest that the new emerging pathogen has the potential to cause severe damages and is a serious threat to naturally distributed species of Pinus in the country. In the period 2018-2019, a spread of L. acicola from the initial outbreak was established throughout stands of P. sylvestris and P. nigra on the territory of Kardzhali District.

The Presentation of Sacralized Rock Mushrooms from Megalithic Sanctuaries in the Bulgarian Lands

The study includes the presentation of sacralized rock mushrooms from megalithic sanctuaries in the Eastern Rhodopes Mountain, in the Western Rhodopes Mountain, images of mushrooms from the sanctuary in the Magura Cave in Western Stara Planina and a number of other monuments from the Bulgarian lands. A semantic and functional analysis of the images in the context of Indo-European religion and in particular of Thracian religion and mythology is proposed.

Structure of the Earth’s crust of the Eastern Rhodopes (Southern Bulgaria) from the regional deep reflection seismic profile Ivaylovgrad–Ardino

This paper presents a geological interpretation of the deep seismic profile Ivaylovgrad–Ardino, which was published in 1996. Four plates are distinguished according to their seismic features that build up the Eastern Rhodope Terrane. They have a total thickness of 22–24 km and layered structures with sub-oceanic character. The lower two plates (1, 2) are westward obducted on the Rila-Western Rhodope Terrane, forming one obduction complex. Plate 3 is probably also a part of the obduction complex. Plate 4 is thrust southward on all plates. A Kobilino Crypto-dome, comprising Plates 1 and 2 and covered discordantly by the third one, is found at the eastern part of the profile at 7–7.5 km depth. The two lower plates do not appear on the surface, but some ultrabasic to basic bodies are supposed to be parts of them, rising as tectonic slices. The Plate 3 is revealed on the surface at the eastern part of the seismic profile (east of Avren Fault), and is built up mainly by the Pre-Rhodopean Supergroup metamorphic rocks, respectively from the seismically indistinguishable Upper and Lower Allochthon. The Plate 4 appears mainly at the western end of the profile (between Mishevsko Village and Ardino Town), and is built up by the metamorphic rocks of the Rhodopean Supergroup from the Startsevo Lithotectonic Unit (or Middle Allochthon). Five fault and shear zone systems of different ages are distinguishable in all plates. Transparent areas in the plates are interpreted as magma chambers of the Paleogene volcanoes, others as Upper Cretaceous and Paleogene (?) plutons. Because these magmatic chambers are located in the sub-oceanic crust, both intermediate and acid Paleogene volcanics have isotopic characteristics similar to those of the metasomatized mantle.

The Neotethys suture in the eastern Bulgarian Rhodopes

<p>Following a tectonic scheme proposed by Janák et al. (2011; Journal of Metamorphic Geology 29, 317-332) and Pleuger et al. (2011; Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 162, 171-192), the Rhodopes are composed of four nappe complexes, from bottom to top the Lower, Middle, and Upper Allochthon and the Circum-Rhodope Belt. Rocks derived from Adria and/or Pelagonia (Lower Allochthon) are separated from rocks of European origin (Upper Allochthon) by lithologically variegated thrust sheets containing sporadic occurrences of ophiolites (Middle Allochthon). These ophiolites typically yield magmatic protolith ages of c. 160 Ma and were metamorphosed under amphibolite- to eclogite-facies conditions. They represent Neotethyan lithosphere subducted below Europe in the Late Cretaceous to Palaeogene whereas the Circum-Rhodope Belt contains ophiolites of the same protolith age but with lower metamorphic grade (greenschist facies at most) and was obducted onto the former European margin in the Jurassic. We present LA-ICP-MS U-Pb zircon and additional geochemical data from the Luda Reka Unit in the Bulgarian Eastern Rhodopes. This unit consists mostly of amphibolite, metagabbro, and metadiorite that yielded two protolith ages of 163.5±2.6 Ma and 154.2±1.0 Ma. The trace element patterns resemble those of typical back-arc basalts and lower oceanic crustal cumulates. Initial epsilon Nd values of six samples calculated to 154 Ma were +10.8 ±0.8 (2σ; n = 6), in agreement with average basalts derived from depleted ambient mantle. A pegmatite crosscutting the Luda Reka Unit yielded a magmatic age of 52.04±1.1 Ma. Such pegmatites are widespread in the Luda Reka Unit (Middle Allochthon) suggesting that emplacement of this unit over the Bjala Reka Orthogneiss Unit (Lower Allochthon) where such pegmatites are lacking happened only after c. 52 Ma. The Bjala Reka Orthogneiss Unit forms the footwall of the top-to-the-SSW Bjala Reka Detachment that became active in the Late Eocene. Where the Luda Reka Unit is lacking, the Bjala Reka Orthogneiss Unit is overlain by rocks that were collectively described as “Low-grade Mesozoic Unit” (e.g. Bonev & Stampfli 2008; Lithos 100, 210-233). Based on peak temperatures determined by Raman spectroscopy of organic matter, two tectonic units can be distinguished in the “Low-grade Mesozoic Unit”. The temperature peak was at c. 530 °C in the Mandrica Unit below and at c. 285 °C in the Maglenica Unit above. For the Mandrica Unit, minimum peak pressures of c. 1.4 GPa were obtained by Raman spectroscopy of quartz inclusions in garnet, indicating that this unit underwent subduction-related metamorphism. Because of this marked difference in peak metamorphic grade, we attribute only the anchimetamorphic Maglenica Unit to the Circum-Rhodope Belt while the high-pressure Mandrica Unit probably represents the Upper Allochthon. Both units are presently separated by the top-to-the-NW Mandrica Detachment that was active before the Bjala Reka Detachment. Our new findings show that the easternmost Rhodopes expose a condensed section through all four nappe complexes, notably including the Neotethys suture.</p>