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Ukkonen P.,University of Helsinki | Aaris-Sorensen K.,Copenhagen University | Arppe L.,University of Helsinki | Clark P.U.,Oregon State University | And 8 more authors.
Quaternary Science Reviews | Year: 2011

Woolly mammoths were large, herbivorous, cold-adapted mammals of the Late Pleistocene. The diet and habitat requirements of the species set certain constraints on the palaeoenvironments it could occupy. The relationship between the mammoth's shifting range and changing environments can be explored using independent data on ice sheet configuration, temperature, and vegetation, provided the locality and age of the fossil remains can be validated. Here we present a comprehensive record of occurrence of the woolly mammoth in the circum-Baltic region of northern Europe during the last glaciation, based on a compilation of radiocarbon-dated remains. The record shows that the mammoth was widespread in northern and north-eastern Europe during Marine Isotope Stage 3 (MIS 3), at 50,000-30,000 calibrated years ago (50-30. ka). The presence of the species up to 65°N latitude supports the restriction of the Scandinavian Ice Sheet (SIS) during MIS 3. The widest distribution range round 30. ka was followed by a decline that led to the disappearance of mammoths from the area during the maximum extent of the SIS, from 22 to 18. ka. The woolly mammoth re-colonized the Baltic region and southern Scandinavia after the onset of the late-glacial deglaciation at 17. ka. The late-glacial record suggests a markedly fluctuating population changing its range in tune with the rapid environmental changes. The last appearance of mammoth in our study region was in Estonia during the Younger Dryas (Greenland Stadial 1; GS1) at about 12. ka. The two major periods of occurrence during MIS 3 and the late-glacial stadial suggest that mammoth had a wide tolerance of open to semi-open tundra and steppe-tundra habitats with intermediately cold climate, whereas the 22-18. ka disappearance suggests a major southward and/or eastward retreat in response to extremely cold, glacial conditions near the SIS margin. The final regional extinction correlates with the re-forestation during the rapid warming at the Younger Dryas-Holocene boundary. © 2010 Elsevier Ltd.


Mikulas R.,Academy of Sciences of the Czech Republic | Meskis S.,University of Latvia | Ivanov A.,Saint Petersburg State University | Luksevics E.,University of Latvia | And 2 more authors.
Bulletin of Geosciences | Year: 2013

Trace fossils and ichnofabrics were recognized in the Middle to Upper Devonian deposits of the East European Platform at the Onega Lake (NW Russia), developed as the Old Red Sandstone facies. The studied sequence is aged from the upper Givetian to the Middle Frasnian. The most diverse ichnoassemblage was ascertained in the earliest Frasnian (lower to middle part of the Andoma Formation), comprising the ichnogenera?Arenituba, Cochlichnus, Cruziana, Diplocraterion, Lockeia, Palaeophycus, Planolites, Rusophycus, Skolithos, Teichichnus, and Undichna. Combination of ichnologic and sedimentary data points to the assumption that these deposits probably originated in wave- and tide-influenced environments, possibly in a brackish-water estuary. Towards the middle Frasnian, Skolithos-like trace fossil dominate; the ichnoassemblage can be attributed to the tidally influenced channels and bars.


Boiko D.,Natural History Museum of Latvia | Kampe-persson H.,Pulmali | Morkunas J.,Institute of Ecology
Wildfowl | Year: 2014

A review of the literature on Whooper Swans Cygnus cygnus breeding in the Baltic states indicates that the swans are recolonising areas where they once bred historically. In recent years, the number of breeding birds has increased from two pairs in 1973 to 600-670 pairs in 2013, though the growth rate has slowed in Latvia, and maybe also in Estonia and Lithuania. There was a clear latitudinal difference in the choice of breeding habitats: in Estonia, the Whooper Swans preferred bogs, lakes and coastal waters, while the vast majority of all pairs in Latvia and Lithuania were found in fishpond complexes and wetlands associated with beaver dams. © Wildfowl & Wetlands Trust


Arppe L.,University of Helsinki | Aaris-Sorensen K.,Copenhagen University | Daugnora L.,Institute of Baltic Sea Region History and Archaeology | Lougas L.,Tallinn University | And 2 more authors.
Quaternary International | Year: 2011

The carbon isotope composition (δ13C) of tooth enamel of woolly mammoth molars from Estonia, Latvia, Lithuania, Denmark and southern Poland was analysed and the data were complemented with previously published δ13C values from Sweden, Finland and northwestern Russia, Switzerland and Britain. The δ13C values display a NE- to SW-trending geographical pattern, with more depleted compositions in the northeast, suggesting differences in the diet consumed by mammoths in the northeastern parts of the study area relative to mammoths in the southwesterly regions. While the pattern is probably a reflection of a number of controlling environmental parameters, with possible additional contribution from physiological factors, statistically significant correlations of the δ13C values to δ18O data from the same specimens and to palaeotemperature estimates imply a strong influence of climate over the δ13C values. The δ13C data do not provide convincing evidence of any temporal changes in diet. © 2010 Elsevier Ltd and INQUA.


Boiko D.,Natural History Museum of Latvia | Kampe-Persson H.,Pulmani
Wildfowl | Year: 2010

This study describes the population status, development, distribution and habitat choice of breeding Whooper Swans Cygnus cygnus breeding in Latvia. The breeding population increased from one breeding pair in 1973 to c. 260 pairs in 2009. The first pair of Whooper Swans nested in the western part of the country, and this area has remained a stronghold for the species within Latvia, supporting 86% of 256 sites where breeding was confirmed during the years 2000-2009, with 54% of pairs found in the districts of Liepaja, Talsi and Kuldiga. Most breeding sites were associated with small water-bodies: 77% were at artificial ponds and 17% at beaver dams. Few nests were found in lakes, mires, bogs and gravel pits. Results are discussed in relation to the increase in Whooper Swan numbers in other parts of Europe. ©Wildfowl & Wedands Trust.


Vasilkova J.,University of Latvia | Luksevics E.,University of Latvia | Stinkulis G.,University of Latvia | Zupins I.,Natural History Museum of Latvia
Estonian Journal of Earth Sciences | Year: 2012

Combined sedimentological and taphonomical study of the siliciclastic sequence of the Tērvete Formation in the stratotypical area was aimed at revealing the formation of the three oryctocoenoses discovered and related structural and textural features of the deposits, as well as at detailed observation of the taphonomical peculiarities of the obtained palaeontological material. The fossil vertebrate assemblage is represented by 14 taxa comprising placoderms, acanthodians, sarcopterygians and actinopterygians. The three oryctocoenoses, first recognized in 2010, differ in the proportions of repeatedly buried material, in the number and degree of preservation of small and fragile skeletal elements, as well as in the evaluated current velocity and the transportation distance. Sedimentary concentrations of marine vertebrate remains, dominated by the antiarchs Bothriolepis ornata and B. jani, have been formed under the influence of fluvial and tidal processes in the shallow-water environment, deltaic or estuarine settings. Elongated placoderm and sarcopterygian bones are probably better indicators of the palaeoflow direction than acanthodian spines or sarcopterygian teeth.


Boiko D.,Natural History Museum of Latvia | Kampe-Persson H.,Pulmani
Ornis Fennica | Year: 2012

This study is the first to demonstrate moult migration in the Whooper Swan Cygnus cygnus. Of cygnets hatched in Latvia and known to be alive about 99% left the country to moult somewhere else in their 2nd-6th calendar year. One-sixth of these were re-sighted in Finland during moult migration; these were solely from western Latvia. Moulting sites were recorded for nine individuals, of which seven had been marked with neck collars and two had satellite transmitters. Five of these nine swans moulted in Latvia, one in Estonia and three in the Arkhangelsk Region of Russia. Distances between sites of ringing and moulting varied between 0 and 1,455 km. All individuals were recorded moulting as two-or three-year old birds. Those moulting in Russia left Latvia/Estonia before 20 June and returned after mid September.


Spectacular increases in range and numbers of some swan and goose species around the Baltic Sea have resulted in more contacts between species and facilitated mixed breeding. Records of mixed breeding and observations during the non-breeding season of mixed families, mixed pairs and hybrids in which at least one of the parent species was a swan were compiled for Sweden. Finland, Leningrad and Kaliningrad Regions of Russia, Estonia, Latvia, Lithuania, Poland, Germany and Denmark. There were twelve records of mixed breeding, nine of Mute Swan x Whooper Swan and one each of Mute Swan x Greylag Goose, Mute Swan x Greater Canada Goose and Whooper Swan x Bewick's Swan. Excluding the two cases involving a goose and two cases involving swans with captive background, there were eight breeding records in the wild. Seven of these can be explained by range expansions. The exception was a case where the identification of the male was unsure.


Boiko D.,Natural History Museum of Latvia | Hakon K.-P.,Pulmani
Wildfowl | Year: 2011

Of 396 Whooper Swan Cygnus cygnus cygnets marked with neck collars in Latvia during the 2004-2008 breeding seasons, 70% were re-sighted at least once in winters 2004/05-2009/10. Overall, 91% of the 2,985 winter re-sightings were of swans seen in Germany, 5% were in Poland and the remaining 4% were distributed across Latvia Lithuania, The Netherlands, Sweden, Denmark, France, Switzerland and Austria. The main wintering areas, situated 760-840 km from the ringing sites, were along the Rivers Elbe and Oder in inland northeast Germany and in neighbouring parts of Poland. The annual proportion of swans marked in Latvia which were re-sighted wintering in this region ranged from 41-80%. The maximum distance between the ringing and wintering sites recorded for each bird averaged 836 km (s.d. ±169 km, range = 407-1,518 km). The average distance between the ringing and wintering sites correlated with winter severity, particularly amongst swans in their second winter or older. © Wildfowl & Wetlands Trust.


Luksevics E.,University of Latvia | Ahlberg P.E.,Uppsala University | Stinkulis G.,University of Latvia | Vasilkova J.,University of Latvia | And 2 more authors.
Lethaia | Year: 2012

The siliciclastic sequence of the Upper Devonian of Kurzeme, Western Latvia, is renowned for abundant vertebrate fossils, including the stem tetrapods Obruchevichthys gracilis and Ventastega curonica. During the first detailed taphonomic study of the vertebrate assemblage from the Ogre Formation cropping out at the Langsēde Cliff, Imula River, abundant vertebrate remains have been examined and identified as belonging to one psammosteid, two acanthodian and three sarcopterygian genera; the placoderm Bothriolepis maxima dominates the assemblage. Besides fully disarticulated placoderm and psammosteid plates, separate sarcopterygian scales and teeth, and acanthodian spines, partly articulated specimens including complete distal segments of Bothriolepis pectoral fins, Bothriolepis head shields and sarcopterygian lower jaws have been found. The size distribution of the placoderm bones demonstrates that the individuals within the assemblage are of approximately uniform age. Distinct zones have been traced within the horizontal distribution of the bones. These linear zones are almost perpendicular to the dominant dip azimuth of the cross-beds and ripple-laminae and most probably correspond to the depressions between subaqueous dunes. Concavity ratio varies significantly within the excavation area. The degree of fragmentation of the bones and disarticulation of the skeletons suggest that the carcasses were reworked and slightly transported before burial. Sedimentological data suggest deposition in a shallow marine environment under the influence of rapid currents. The fossiliferous bed consists of a basal bone conglomerate covered by a cross-stratified sandstone with mud drapes, which is in turn overlain by ripple laminated sandstone, indicating the bones were buried by the gradual infilling of a tidal channel. All the Middle-Upper Devonian vertebrate bone-beds from Latvia are associated with sandy to clayey deposits and have been formed in a sea-coastal zone during rapid sedimentation episodes, but differ in fossil abundance and degree of preservation. □Agnathans, Devonian, facies analysis, fish, fossil assemblage, palaeoenvironment. © 2011 The Authors, Lethaia © 2011 The Lethaia Foundation.

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