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1.
Mar Pollut Bull ; 205: 116605, 2024 Jun 17.
Article En | MEDLINE | ID: mdl-38889665

Total Mercury (THg) content was determined in the fur of 64 Caspian seals, in the whiskers of 59 individuals and whole blood of 29 individuals. The THg content in Caspian seal fur varied from 258 to 8511 µg/kg, in whiskers from 954 to 12,957 µg/kg, and in whole blood from 88 to 350 µg/l. There were no statistically significant differences in mercury concentration in biomaterial between males and females (Kruskal-Wallis test, p < 0.05). The 1-2-year-old seals contained less mercury compared to older seals. The THg content in Caspian seal samples was comparable to seals from different regions of North Eurasia. Four individuals had mercury concentrations in their fur above the threshold values that can lead to nervous system disorders (>5400 µg/kg).

2.
Dokl Biol Sci ; 512(1): 295-299, 2023 Oct.
Article En | MEDLINE | ID: mdl-38087016

The relationship between postures, sleep stages and eye state was established in two species of deer, the Indian sambar (Rusa unicolor) and sika deer (Cervus nippon), based on video recording. In both species, the state of rest or behavioral sleep was recorded in the sternal position, holding the head above the ground, and in the lateral position, with the head resting on the croup or on the ground. Rest accounted for at least 80% of the time in these positions. Based on behavior criteria a substantial portion of rest represented slow-wave sleep. Episodes of rapid eye movements (REM sleep) were recorded in the lateral position. They did not exceed 2 min. When the deer were in the sternal posture, they kept their eyes open most of the time: in average 96% of the time in sambars and 82% in sika deer. Episodes of the open eye in this posture lasted up to 8.4 min in sambars and up to 3.3 min in sika deer. In the lateral position, such episodes were 4 and 1.5 times shorter. Sleeping with open eyes in ungulates may be an important mechanism of maintaining vigilance.


Deer , Animals , Sleep
3.
Dokl Biol Sci ; 512(1): 311-316, 2023 Oct.
Article En | MEDLINE | ID: mdl-38087019

Polymorphism of nine microsatellite loci in the Sikhote-Alin tiger population was analyzed in the modern and recent historical periods, using blood, excrement, and museum bone samples. Tests for excess heterozygosity to determine whether the population went through a period of low abundance and a low value of the Garza-Williamson coefficient indicated that such events were highly probable to occur in both recent and earlier history. The mean effective population size Ne of a current sample was 34.4 (95% confidence interval 17-106.8). This fact is of great interest in the contest of conservation and restoration of endangered large cat species.


Tigers , Animals , Tigers/genetics , Endangered Species , Population Density , Microsatellite Repeats/genetics , Genetic Variation/genetics
4.
Dokl Biol Sci ; 513(1): 395-399, 2023 Dec.
Article En | MEDLINE | ID: mdl-37950812

For the first time, using GPS-GSM trackers, long-term seasonal flights of greater noctule bat (Nyctalus lasiopterus) from summer habitats in Russia to wintering areas in Europe are recorded. One of the seasonal migratory flights is a record distance for bats (2515 km). The maximum daily flight was 445 km. One of the animals abruptly changed the direction of migration from southwest to north on the third day of flight after crossing the Kursk magnetic anomaly.


Chiroptera , Animals , Seasons , Europe , Ecosystem , Russia , Animal Migration
5.
Dokl Biol Sci ; 511(1): 247-250, 2023 Aug.
Article En | MEDLINE | ID: mdl-37833580

Nucleotide sequence diversity in two mtDNA loci (the cytochrome b gene and the control region) was for the first time studied in the Baikal seal Pusa sibirica with the use of several spatiotemporal samples. The population was found to be evolutionarily young and to be in the stage of demographic expansion.


Seals, Earless , Animals , Seals, Earless/genetics , Base Sequence
6.
Dokl Biol Sci ; 508(1): 76-80, 2023 Feb.
Article En | MEDLINE | ID: mdl-37186051

For the first time, information is provided on the size of the home range of Siberian forest reindeer (Rangifer tarandus valentinae) of the Altai-Sayan population of Kuznetsk Alatau, the minimum distance that the deer passes per day, their changes, and changes of habitats during the annual cycle. Possible reasons for the cyclical use of the habitat by forest reindeer are discussed.


Deer , Reindeer , Animals , Forests
8.
Dokl Biochem Biophys ; 506(1): 223-226, 2022 Oct.
Article En | MEDLINE | ID: mdl-36303057

A noninvasive instrumental method of classification the behavior of the beluga whale (Delphinapterus leucas) based on the parameters of movement was evaluated. Motor activity was characterized by the mean and standard deviation of the beluga tail fluke acceleration. It was found that, using the "decision tree" algorithm, at least two types of beluga behaviors can be distinguished: resting at the surface and active swimming in the pool. The determination accuracy (depending on the parameter) was, on average, 81-97% for resting at the surface and 54-99% for active swimming behaviors. Differences between the accuracy of classification of resting at the surface based on three axis and overall body acceleration were minimal. In the future, the accuracy may be improved by using other acceleration parameters, shortening the interval of analysis, and optimizing the classification algorithms.


Beluga Whale , Animals , Acceleration
9.
Dokl Biol Sci ; 502(1): 36-41, 2022 Jun.
Article En | MEDLINE | ID: mdl-35298752

New data on the diet of the wild reindeer (Rangifer tarandus pearsoni) on the Yuzhny Island of the Novaya Zemlya archipelago in the summer are presented. The coprological method shows the predominance of vascular plants in the studied samples of reindeer feces. The selectivity of reindeer in relation to pasture habitats and forage groups of plants indicates that the area and variety of forage lands in the summer are sufficient for the reindeer and are not limiting factors for it.


Reindeer , Animals , Diet , Seasons
10.
Dokl Biol Sci ; 500(1): 153-158, 2021 Sep.
Article En | MEDLINE | ID: mdl-34731381

The pattern of sleep and circadian activity of the lesser mouse-deer (Tragulus kanchil) that is the smallest (body mass between 1.5 and 2.2 kg) representative of the basal group (Tragulidae) of even-toed ungulates which evolved 40-50 Ma were studied. In naturalistic conditions, a total of 30 days of full-day video of the animal behavior and 15 days of 24-h polysomnographic data were collected in 6 animals. The mouse-deer were active less than 20% of 24 h and were quiescent during 60-80% of the remaining time. Slow wave sleep (SWS) accounted for on average 49.7 ± 3.7% of 24 h and paradoxical (rapid eye movement, REM) sleep accounted for 1.7 ± 0.3% of 24 h. During the majority of SWS (87.0 ± 4.4%) the eyes were open. The most of SWS and REM sleep occurred during the daytime hours (9 a.m. to 4 p.m.) and in the first half of the night (8 p.m. to 2 a.m.); the animals were most active during twilight hours (4-6 a.m. and 6-7 p.m.). We suggest that the main features of sleep in the mouse-deer are largely determined by ecological factors, including environmental temperature and predation, as well as the size and physiology of the mouse-deer.


Deer , Wakefulness , Animals , Circadian Rhythm , Electroencephalography , Mice , Sleep , Sleep Stages , Sleep, REM
11.
Dokl Biol Sci ; 494(1): 255-259, 2020 Sep.
Article En | MEDLINE | ID: mdl-33083885

This is the first study to show the genetic identity of the Altai-Sayan population of the forest reindeer of the Kuznetsk Alatau (Rangifer tarandus valentinae). The population is characterized by the existence of unique mitochondrial lines, the absence of signs of introgression of domestic rein deer mtDNA, as well as a low level of genetic diversity. In the sample studied, only two nucleotide substitutions (both of them transitions) were revealed, the nucleotide diversity (0.0015 ± 0.00136) was almost ten times lower than in most populations of wild reindeer in Russia and was comparable only with that of some wild reindeer populations of Norway and Svalbard. The haplotype diversity (h) was also relatively low (0.615 ± 0.102).


DNA, Mitochondrial/genetics , Genetic Variation/genetics , Reindeer/genetics , Animals , Forests , Haplotypes/genetics , Russia
12.
Dokl Biol Sci ; 493(1): 141-146, 2020 Jul.
Article En | MEDLINE | ID: mdl-32894430

For the first time, the relationship of lipid and fatty acid composition with individual, gender and age characteristics of the gray whale Eschrichtius robustus in the Piltun feeding area is shown using the methods of biochemical analysis.


Adipose Tissue/chemistry , Lipids/analysis , Whales/physiology , Adipose Tissue/metabolism , Age Factors , Animal Migration , Animal Nutritional Physiological Phenomena , Animals , Fatty Acids/analysis , Fatty Acids/chemistry , Female , Food Chain , Lipids/chemistry , Male , Pacific Ocean , Skin/chemistry
13.
Dokl Biol Sci ; 485(1): 47-51, 2019 Mar.
Article En | MEDLINE | ID: mdl-31197594

Genetic studies of the ferret badgers Melogale conducted in Vietnam have shown that this area is inhabited by three species, M. moschata, M. personata, and M. cucphuongensis, which can be attributed to sibling species (cryptic species). M. personata was found to be widespread not only in southern and central Vietnam, but also in the northern provinces (Lang Son, Ha Giang, Ninh Binh), while M. cucphuongensis was found in the provinces Lang Son, Ha Giang, Cao Bang, and Dak Lak, apart from Ninh Binh, from where it was described. The data obtained suggest a sympatric distribution of all three species over the Vietnam area and confirm sympatry of M. personata and M. moschata in southern Vietnam, which has been earlier established on the basis of morphological data.


DNA, Mitochondrial/genetics , Mustelidae/classification , Phylogeny , Animal Distribution , Animals , Mustelidae/genetics , Mustelidae/physiology , Phylogeography , Vietnam
14.
Dokl Biol Sci ; 481(1): 135-138, 2018 Jul.
Article En | MEDLINE | ID: mdl-30171465

The frequency resolving power of hearing (FRP) of the beluga whale Delphinapterus leucas was studied as dependent on influence of lasting low-intensity sounds (of the ultrasonic range from -20 to +10 dB). Testing of the spectrum ripple-phase reversal was used in conjunction with a noninvasive recording of auditory evoked potentials. FRP parameters were found to depend nonmonotonically on the intensity of the background noise. The resultant adaptation effects can be explained by the fact that, in response to the high-intensity signals, the auditory system sensitivity is reduced to the level optimal for analysis of these signals.


Beluga Whale/physiology , Noise , Acoustic Stimulation , Animals , Evoked Potentials, Auditory/physiology
15.
Dokl Biol Sci ; 480(1): 93-96, 2018 May.
Article En | MEDLINE | ID: mdl-30009348

The data on the content of carbon and nitrogen isotopes in the blood samples of polar bears obtained in the present study confirm that polar bears in the Taimyr region (and the Kara-Barents sea population in general) are partly dependent on the resources of terrestrial origin. However the "terrestrial carbon" evidently reaches bears' tissues indirectly, via marine food webs utilizing organic carbon brought into the polar basin by Siberian rivers.


Carbon Isotopes/blood , Food Chain , Nitrogen Isotopes/blood , Ursidae/blood , Animals , Arctic Regions , Female , Male , Siberia
16.
Dokl Biol Sci ; 474(1): 110-113, 2017 May.
Article En | MEDLINE | ID: mdl-28702724

The alarm call acoustic structure and nonlinear vocal phenomena of the Indian sambar (Rusa unicolor) and northern Indian muntjac (Muntiacus vaginalis) have been analyzed in detail as well as their vocal behavior in response to mobbing humans under natural conditions of southern Vietnam. The alarm calls of sambars, tonal barks separated by large intervals, were produced by animals standing on the place and gazing at a potentially dangerous object. Muntjacs flee off in danger and produced a series of dull barks interrupted with short intervals from a distance. The alarm call frequencies were characterized for sambars and muntjacs. The results of our study have been compared with the published data on alarm calls of other Cervidae species.


Acoustics , Muntjacs/physiology , Vocalization, Animal/physiology , Animals , Vietnam
17.
Dokl Biol Sci ; 472(1): 17-20, 2017 Jan.
Article En | MEDLINE | ID: mdl-28429262

The polar bear movement trajectory in relation to onset date of the sea-ice break-up was studied in the coastal zone of the Taimyr Peninsula, eastern part of the Kara Sea, using as an example a female polar bear tagged by a radio collar with an Argos satellite transmitter. Analysis of the long-term pattern of ice melting and tracking, by means of satellite telemetry, of the female polar bear who followed the ice-edge outgoing in the north-eastern direction (in summer 2012) suggests that direction of the polar bear movement depends precisely on the direction of the sea-ice cover break-up.


Animal Migration/physiology , Ice , Seasons , Ursidae/physiology , Animals , Arctic Regions , Female
18.
Dokl Biol Sci ; 477(1): 236-238, 2017 Nov.
Article En | MEDLINE | ID: mdl-29299808

Abundance of 388 ± 108 whales for the Okhotsk Sea bowhead whale population based on individual genotyping was estimated using the capture-recapture method for the open population model. The data demonstrate that this endangered population shows no signs of recovery.


Bowhead Whale/genetics , Endangered Species/statistics & numerical data , Animals , Bowhead Whale/physiology , Genotype , Siberia
20.
Dokl Biol Sci ; 471(1): 261-265, 2016 Nov.
Article En | MEDLINE | ID: mdl-28058605

In bowhead whales summering in Ulbanskiy Bay of the Okhotsk Sea, molting of epidermis has been found and histologically confirmed. The outer layer of the molting whale epidermis is longitudinally stratified and rejected in the form of relatively large plates up to several millimeters thick, each representing a lamellar formation consisting of longitudinal rows of parakeratocytes with degenerated nuclei, numerous pigment granules, and lipid inclusions. Molting intensity is correlated with the level of proliferation and regeneration of all epidermal layers, which helps to maintain the optimal skin thickness.


Bowhead Whale/anatomy & histology , Bowhead Whale/physiology , Epidermal Cells , Epidermis/physiology , Molting/physiology , Seasons , Animals , Arctic Regions , Climate , Pacific Ocean , Species Specificity
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