L. Peichl, Tijana Radic, I. Solovei, Michael Wolfram, M. Glösmann
The retina of the fat dormouse Glis glis was studied histologically. Opsin immunolabeling identified an unusually dense population of rod photoreceptors (ca. 600,000–780,000/mm²) and a low-density population of L cone photoreceptors containing the longwave-sensitive (LWS) cone opsin, with a shallow maximum of ca. 3,300/mm² in temporal retina and ca. 2,000–3,000/mm² in the remaining retina. Hence the cones comprise only 0.25–0.50% of the photoreceptors. There are no S cones expressing the shortwave-sensitive (SWS1) opsin that is the second cone opsin in most mammals, conveying dichromatic colour vision. We conclude that the fat dormouse is a cone monochromat. Sequencing of the tuning-relevant exon 1 of the SWS1 opsin gene revealed that the gene would have coded for a UV-sensitive visual pigment, but that it contains mutational changes making it nonfunctional. Retinal interneurons (rod bipolar cells, horizontal cells, several amacrine cell types) have rodent-typical features. NeuN-labeled presumed retinal ganglion cells have densities between ca. 4000/mm² in temporal central retina and 850–1300/mm² in peripheral retina. The peak ganglion cell density would result in an estimated visual acuity maximum of ca. 1.8 cycles/degree or ca. 33 minutes of arc. Assessment of a further Gliridae species, the African dormouse Graphiurus sp., also revealed a high rod density, low L cone density, and an absence of SWS1 opsin.
{"title":"On the retinae of Glis and Graphiurus: photoreceptor and ganglion cell populations, an absence of shortwave-sensitive cones, and some other features (Rodentia: Gliridae)","authors":"L. Peichl, Tijana Radic, I. Solovei, Michael Wolfram, M. Glösmann","doi":"10.37520/lynx.2022.013","DOIUrl":"https://doi.org/10.37520/lynx.2022.013","url":null,"abstract":"The retina of the fat dormouse Glis glis was studied histologically. Opsin immunolabeling identified an unusually dense population of rod photoreceptors (ca. 600,000–780,000/mm²) and a low-density population of L cone photoreceptors containing the longwave-sensitive (LWS) cone opsin, with a shallow maximum of ca. 3,300/mm² in temporal retina and ca. 2,000–3,000/mm² in the remaining retina. Hence the cones comprise only 0.25–0.50% of the photoreceptors. There are no S cones expressing the shortwave-sensitive (SWS1) opsin that is the second cone opsin in most mammals, conveying dichromatic colour vision. We conclude that the fat dormouse is a cone monochromat. Sequencing of the tuning-relevant exon 1 of the SWS1 opsin gene revealed that the gene would have coded for a UV-sensitive visual pigment, but that it contains mutational changes making it nonfunctional. Retinal interneurons (rod bipolar cells, horizontal cells, several amacrine cell types) have rodent-typical features. NeuN-labeled presumed retinal ganglion cells have densities between ca. 4000/mm² in temporal central retina and 850–1300/mm² in peripheral retina. The peak ganglion cell density would result in an estimated visual acuity maximum of ca. 1.8 cycles/degree or ca. 33 minutes of arc. Assessment of a further Gliridae species, the African dormouse Graphiurus sp., also revealed a high rod density, low L cone density, and an absence of SWS1 opsin.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121152651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Between 2001 and 2016, 31 zoological excursions of the Department of General Zoology of the University of Duisburg-Essen (Germany) took place in South Bohemia (Czech Republic), mainly in the the Šumava Mountains south of Sušice. Under the leadership of Professor Hynek Burda and his colleagues, more than 170 vertebrate species (including 37 mammals) were sighted, heard or confirmed in another way in the visited region during this time. In addition, we found about 60 arthropod species. This report lists all these species in a summary table. Particularly noteworthy finds include Eurasian lynx (Lynx lynx), Eurasian otter (Lutra lutra), Eurasian beaver (Castor fiber) and several microchiropterans like Bechstein’s bat (Myotis bechsteinii), lesser horseshoe bat (Rhinolophus hipposideros) or Nathusius’ pipistrelle (Pipistrellus nathusii). Other interesting records are hazel grouse (Tetrastes bonasia), Eurasian three-toed woodpecker (Picoides tridactylus) and common adder (Vipera berus).
{"title":"Species on an excursion – Mammals and other faunistic records from 16 years of zoological field trips to the Šumava Mountains and South Bohemia (Czech Republic) under the direction of Hynek Burda","authors":"M. Schmitt","doi":"10.37520/lynx.2022.026","DOIUrl":"https://doi.org/10.37520/lynx.2022.026","url":null,"abstract":"Between 2001 and 2016, 31 zoological excursions of the Department of General Zoology of the University of Duisburg-Essen (Germany) took place in South Bohemia (Czech Republic), mainly in the the Šumava Mountains south of Sušice. Under the leadership of Professor Hynek Burda and his colleagues, more than 170 vertebrate species (including 37 mammals) were sighted, heard or confirmed in another way in the visited region during this time. In addition, we found about 60 arthropod species. This report lists all these species in a summary table. Particularly noteworthy finds include Eurasian lynx (Lynx lynx), Eurasian otter (Lutra lutra), Eurasian beaver (Castor fiber) and several microchiropterans like Bechstein’s bat (Myotis bechsteinii), lesser horseshoe bat (Rhinolophus hipposideros) or Nathusius’ pipistrelle (Pipistrellus nathusii). Other interesting records are hazel grouse (Tetrastes bonasia), Eurasian three-toed woodpecker (Picoides tridactylus) and common adder (Vipera berus).","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115101327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The bat fauna was studied at six localities of protected natural forest fragments in the southern part of the Brdy Mts. (south-western Bohemia), in the years 2019–2020. Netting and acoustic detection on line transects were used in order to document the species composition and flight activity of bats at the localities under study. Altogether, 24 individuals of seven bat species were netted. In total, 643 minutes of the presence of flying bats were registered within 56.5 transect hours. With use of these methods, at least 16 bat species were recorded. Of them, Myotis myotis, M. mystacinus / M. brandtii, M. nattereri, Eptesicus nilssonii, Pipistrellus pipistrellus, Plecotus auritus, and Barbastella barbastellus represent the constant species group with respect to their occurrence at the localities. Pipistrellus pipistrellus was the most frequent species (54%), with the highest relative flight activity at all localities. The highest intensity of flight activity of the bat community was observed in habitats with rocks, boulder accumulation, and open stony debris (14.17 min+/h). The highest bat species diversity was registered in habitats with the prevalence of herb-rich mixed beech forest stands (15 species, diversity index H’=2.02; equitability E=0.75). A series of calls of Hypsugo savii was registered in the Na skalách Nature Reserve on 8 May 2020. It represents the first finding of this species in the region of the Brdy Mts.
{"title":"Fauna and flight activity of bats in natural forests in the southern Brdy Mts. and the first information on the occurrence of Hypsugo savii in this area (Chiroptera: Vespertilionidae)","authors":"L. Bufka, Romana Zachová","doi":"10.37520/lynx.2021.005","DOIUrl":"https://doi.org/10.37520/lynx.2021.005","url":null,"abstract":"The bat fauna was studied at six localities of protected natural forest fragments in the southern part of the Brdy Mts. (south-western Bohemia), in the years 2019–2020. Netting and acoustic detection on line transects were used in order to document the species composition and flight activity of bats at the localities under study. Altogether, 24 individuals of seven bat species were netted. In total, 643 minutes of the presence of flying bats were registered within 56.5 transect hours. With use of these methods, at least 16 bat species were recorded. Of them, Myotis myotis, M. mystacinus / M. brandtii, M. nattereri, Eptesicus nilssonii, Pipistrellus pipistrellus, Plecotus auritus, and Barbastella barbastellus represent the constant species group with respect to their occurrence at the localities. Pipistrellus pipistrellus was the most frequent species (54%), with the highest relative flight activity at all localities. The highest intensity of flight activity of the bat community was observed in habitats with rocks, boulder accumulation, and open stony debris (14.17 min+/h). The highest bat species diversity was registered in habitats with the prevalence of herb-rich mixed beech forest stands (15 species, diversity index H’=2.02; equitability E=0.75). A series of calls of Hypsugo savii was registered in the Na skalách Nature Reserve on 8 May 2020. It represents the first finding of this species in the region of the Brdy Mts.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127196469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Okrouhlík, M. Zemanova, Pavlína Plánková, R. Šumbera
In our study, we analyzed two poorly known aspects of thermal biology in subterranean rodents, the African mole-rats, that being daily energy expenditure and development of thermoregulation in juvenile mole-rat using the social Mashona mole-rat, Fukomys darlingi from southern Malawi. We performed laboratory measurements over 24 h to assess the daily energy expenditure (DEE) in adults as well as the development of the thermoregulatory abilities of juveniles at different ages. To assess the effect of ambient temperature (Ta), we exposed mole-rats to either 30 °C or 20 °C, which represents a thermoneutral as well as a thermally challenging temperature, respectively. The DEE at a Ta of 20 °C was lower than expected based on the calculation from the resting metabolic rate (RMR) at the same Ta, this suggested that heat derived from physical activity can substitute the thermoregulatory heat and thus decrease the cost on thermoregulation. To assess the development of thermoregulation in juveniles and the effect of the presence of family members on it, we measured core body temperature (Tb) and resting metabolic rate (RMR) in juveniles under several social contexts: while alone, with littermates, with littermates and mother and with littermates and both parents. Only juveniles older than one month could generate heat to keep Tb higher than Ta. Thermoregulation appeared to be fully developed in three-month-old juveniles. The presence of adult(s), but not littermates, helped to increase Tb and to decrease the RMR of juveniles. Although the results are mostly preliminary and some interpretations are limited due to low sample size in some social contexts, we may conclude that in this mole-rat species, development of thermoregulation is slow even compared to other altricial mammals.
{"title":"Unexplored aspects of African mole-rat thermal biology: Daily energy expenditure and development of thermoregulation in Fukomys darlingi (Rodentia: Bathyergidae)","authors":"J. Okrouhlík, M. Zemanova, Pavlína Plánková, R. Šumbera","doi":"10.37520/lynx.2022.005","DOIUrl":"https://doi.org/10.37520/lynx.2022.005","url":null,"abstract":"In our study, we analyzed two poorly known aspects of thermal biology in subterranean rodents, the African mole-rats, that being daily energy expenditure and development of thermoregulation in juvenile mole-rat using the social Mashona mole-rat, Fukomys darlingi from southern Malawi. We performed laboratory measurements over 24 h to assess the daily energy expenditure (DEE) in adults as well as the development of the thermoregulatory abilities of juveniles at different ages. To assess the effect of ambient temperature (Ta), we exposed mole-rats to either 30 °C or 20 °C, which represents a thermoneutral as well as a thermally challenging temperature, respectively. The DEE at a Ta of 20 °C was lower than expected based on the calculation from the resting metabolic rate (RMR) at the same Ta, this suggested that heat derived from physical activity can substitute the thermoregulatory heat and thus decrease the cost on thermoregulation. To assess the development of thermoregulation in juveniles and the effect of the presence of family members on it, we measured core body temperature (Tb) and resting metabolic rate (RMR) in juveniles under several social contexts: while alone, with littermates, with littermates and mother and with littermates and both parents. Only juveniles older than one month could generate heat to keep Tb higher than Ta. Thermoregulation appeared to be fully developed in three-month-old juveniles. The presence of adult(s), but not littermates, helped to increase Tb and to decrease the RMR of juveniles. Although the results are mostly preliminary and some interpretations are limited due to low sample size in some social contexts, we may conclude that in this mole-rat species, development of thermoregulation is slow even compared to other altricial mammals.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126203226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the African mole-rat family (Bathyergidae), species show both year-round and seasonal breeding patterns even though all species inhabit regions with varying seasonal rainfall patterns (a well-known selection driver of seasonal breeding). This short review suggests a novel hypothesis explaining why some African mole-rat species breed seasonally and others year-round. Namely, group-living African mole-rat species (with a mean colony size greater than five) exhibit an aseasonal reproduction pattern, as breeders, particularly females, possess year-round high body conditions. This is likely due to access to abundant and high-quality resources (food and water) throughout the year and reduced frequency of engaging in strenuous activities, such as digging, due to the increased efficiency of locating and retrieval of resource as a function of group size. While in the solitary and social species, with mean colony sizes of five or less, there are too few colony members to provide sufficient cooperative care benefits, the breeders show a seasonality to their body condition and thus breeding investment. As such, we hope to start a discussion on how group size could affect circannual breeding rhythms and propose some avenues for future research.
{"title":"Seasonality of reproduction in Bathyergidae is a function of group size: A novel hypothesis (Rodentia)","authors":"D. W. Hart, N. Bennett","doi":"10.37520/lynx.2022.004","DOIUrl":"https://doi.org/10.37520/lynx.2022.004","url":null,"abstract":"In the African mole-rat family (Bathyergidae), species show both year-round and seasonal breeding patterns even though all species inhabit regions with varying seasonal rainfall patterns (a well-known selection driver of seasonal breeding). This short review suggests a novel hypothesis explaining why some African mole-rat species breed seasonally and others year-round. Namely, group-living African mole-rat species (with a mean colony size greater than five) exhibit an aseasonal reproduction pattern, as breeders, particularly females, possess year-round high body conditions. This is likely due to access to abundant and high-quality resources (food and water) throughout the year and reduced frequency of engaging in strenuous activities, such as digging, due to the increased efficiency of locating and retrieval of resource as a function of group size. While in the solitary and social species, with mean colony sizes of five or less, there are too few colony members to provide sufficient cooperative care benefits, the breeders show a seasonality to their body condition and thus breeding investment. As such, we hope to start a discussion on how group size could affect circannual breeding rhythms and propose some avenues for future research.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"304 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123226696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shrews look rather similar at first sight, but a closer look reveals many different specializations according to different lifestyles. In this study, we took a closer look on the auricle of shrews. To reveal morphological adaptations, we analysed the inclination of the outer ear in relation to the nostril-eye-line, and its visibility. We could show that not only environmental cues have an influence on the shape of the outer ear, but there exist also differences at the subfamily level. We found a clear separation between Soricinae, Myosoricinae, and Crocidurinae concerning the visibility and the inclination of the auricle. Within the limits of a subfamily the auricle is modified due to behavioural and environmental constraints. Especially within Myosoricinae adaptations to a semi-fossorial life are well visible.
{"title":"Morphology and adaptation of the auricle in Soricidae (Lipotyphla)","authors":"Christian Montermann, R. Hutterer","doi":"10.37520/lynx.2022.023","DOIUrl":"https://doi.org/10.37520/lynx.2022.023","url":null,"abstract":"Shrews look rather similar at first sight, but a closer look reveals many different specializations according to different lifestyles. In this study, we took a closer look on the auricle of shrews. To reveal morphological adaptations, we analysed the inclination of the outer ear in relation to the nostril-eye-line, and its visibility. We could show that not only environmental cues have an influence on the shape of the outer ear, but there exist also differences at the subfamily level. We found a clear separation between Soricinae, Myosoricinae, and Crocidurinae concerning the visibility and the inclination of the auricle. Within the limits of a subfamily the auricle is modified due to behavioural and environmental constraints. Especially within Myosoricinae adaptations to a semi-fossorial life are well visible.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130099769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The population of the wild boar (Sus scrofa) in the Czech Republic has been steadily increasing for the last 70 years. The only comparable tangible data are provided by the available harvest statistics. Disputes over the damage caused by wild boar are endless, and the dynamics of the species expansion have not yet been properly explained. The authors therefore present the harvest statistics as the only available data on which the wild boar population growth in the 20th century can be documented.
{"title":"Sus scrofa in the Czech Republic from the perspective of hunting statistics (Cetartiodactyla: Suidae)","authors":"Jan Andreska, Kateřina Krupková","doi":"10.37520/lynx.2021.002","DOIUrl":"https://doi.org/10.37520/lynx.2021.002","url":null,"abstract":"The population of the wild boar (Sus scrofa) in the Czech Republic has been steadily increasing for the last 70 years. The only comparable tangible data are provided by the available harvest statistics. Disputes over the damage caused by wild boar are endless, and the dynamics of the species expansion have not yet been properly explained. The authors therefore present the harvest statistics as the only available data on which the wild boar population growth in the 20th century can be documented.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133006079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Studies of learned magnetic compass orientation by C57 BL/6 mice were carried out to determine if responses to magnetic cues were disrupted by exposure to a very low-level (1–2 nT) 1.46 MHz radio frequency field. Findings show that exposure to the same intensity of the 1.46 MHz RF in training and testing (1.0 to 1.2 nT) had no effect on magnetic compass orientation. However, exposure to a slightly higher intensity of RF in training (1.3 to 2.1 nT) eliminated magnetic compass orientation either because the stronger intensity was above a critical threshold for disruption of the underlying magnetoreception mechanism, or because the difference in the RF intensities in training and testing resulted in qualitatively different patterns of magnetic input (‘magnetic modulation patterns’). Importantly, although similar effects of RF on magnetic compass orientation have been reported in other organisms, sensitivity to such low intensities of RF fields cannot be explained by current models of the mechanisms of magnetoreception in terrestrial organisms. Consequently, future research to determine if the findings from C57 BL/6 reported here are replicable is of the first importance.
{"title":"Small differences in weak electromagnetic fields disrupt magnetic compass orientation of C57 BL/6 mice (Rodentia: Muridae)","authors":"J. Phillips, Michael S. Painter","doi":"10.37520/lynx.2022.015","DOIUrl":"https://doi.org/10.37520/lynx.2022.015","url":null,"abstract":"Studies of learned magnetic compass orientation by C57 BL/6 mice were carried out to determine if responses to magnetic cues were disrupted by exposure to a very low-level (1–2 nT) 1.46 MHz radio frequency field. Findings show that exposure to the same intensity of the 1.46 MHz RF in training and testing (1.0 to 1.2 nT) had no effect on magnetic compass orientation. However, exposure to a slightly higher intensity of RF in training (1.3 to 2.1 nT) eliminated magnetic compass orientation either because the stronger intensity was above a critical threshold for disruption of the underlying magnetoreception mechanism, or because the difference in the RF intensities in training and testing resulted in qualitatively different patterns of magnetic input (‘magnetic modulation patterns’). Importantly, although similar effects of RF on magnetic compass orientation have been reported in other organisms, sensitivity to such low intensities of RF fields cannot be explained by current models of the mechanisms of magnetoreception in terrestrial organisms. Consequently, future research to determine if the findings from C57 BL/6 reported here are replicable is of the first importance.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133274426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In 2020, an extremely high mortality of juveniles was recorded in a nursery colony of Myotis myotis at Žihobce (Klatovy Dist.), reaching 50.6% of the potential growth. Most juveniles died within two weeks of age (67.4%). The cause of this phenomenon is not known. The results of chemical analyses carried out in five dead juveniles showed neither the presence of heavy metals nor pesticides in the bodies. The dissection of cadavers revealed a good nutrition state. In all dissected individuals, intestinal inflammation was recorded. Most juveniles in the colony were significantly parasitised. In the period of parturition, it was cold and very rainy for several days, the mortality thus may have been caused by chilling of the juveniles. The effort of females to nurse even the dying juveniles which fell down from the colony was observed. The mortality of juveniles was checked in further 28 control colonies in different parts of the Czech Republic in 2020. At eight sites, making up 27.6% of all studied sites, the mortality of 10.1–20.0% was recorded. At the remaining twenty sites (69% of the studied sites), the mortality reached 0–10%. High mortality of juveniles of M. myotis (18.7–39.2%) was also recorded at Vyšší Brod (Český Krumlov Dist.) in the years 1988–1991. In that case, the probable cause was the application of Lastanox (tributyltin oxide), a toxic chemical used for timber treatment in the colony roost.
2020年，在Žihobce (Klatovy地区)的Myotis Myotis苗圃种群中记录到极高的幼崽死亡率，达到潜在增长率的50.6%。大多数幼鱼在两周内死亡(67.4%)。造成这种现象的原因尚不清楚。对5只死去的幼鱼进行的化学分析结果显示，它们的体内既没有重金属，也没有杀虫剂。尸体解剖显示其营养状况良好。在所有被解剖的个体中，记录了肠道炎症。蚁群中大多数幼虫被严重寄生。在分娩期间，一连几天天气寒冷且多雨，因此幼崽的死亡可能是由于受寒所致。观察到雌蚁甚至会努力哺育从蚁群中掉下来的垂死的幼蚁。2020年，在捷克共和国不同地区的另外28个对照种群中，对青少年的死亡率进行了检查。8个站点的死亡率为10.1-20.0%，占所有研究站点的27.6%。其余20个站点(占研究站点的69%)死亡率为0-10%。1988-1991年在Vyšší Brod (Český Krumlov区)也发现了高死亡率(18.7-39.2%)。在那个案例中，可能的原因是使用了Lastanox(氧化三丁基锡)，这是一种用于处理殖民地栖息地木材的有毒化学物质。
{"title":"Extremely high mortality of newborn juveniles in the nursery colony of Myotis myotis at Žihobce, SW Bohemia, Czech Republic (Chiroptera: Vespertilionidae)","authors":"J. Červený, L. Bufka","doi":"10.37520/LYNX.2020.003","DOIUrl":"https://doi.org/10.37520/LYNX.2020.003","url":null,"abstract":"In 2020, an extremely high mortality of juveniles was recorded in a nursery colony of Myotis myotis at Žihobce (Klatovy Dist.), reaching 50.6% of the potential growth. Most juveniles died within two weeks of age (67.4%). The cause of this phenomenon is not known. The results of chemical analyses carried out in five dead juveniles showed neither the presence of heavy metals nor pesticides in the bodies. The dissection of cadavers revealed a good nutrition state. In all dissected individuals, intestinal inflammation was recorded. Most juveniles in the colony were significantly parasitised. In the period of parturition, it was cold and very rainy for several days, the mortality thus may have been caused by chilling of the juveniles. The effort of females to nurse even the dying juveniles which fell down from the colony was observed. The mortality of juveniles was checked in further 28 control colonies in different parts of the Czech Republic in 2020. At eight sites, making up 27.6% of all studied sites, the mortality of 10.1–20.0% was recorded. At the remaining twenty sites (69% of the studied sites), the mortality reached 0–10%. High mortality of juveniles of M. myotis (18.7–39.2%) was also recorded at Vyšší Brod (Český Krumlov Dist.) in the years 1988–1991. In that case, the probable cause was the application of Lastanox (tributyltin oxide), a toxic chemical used for timber treatment in the colony roost.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121411911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To understand the evolutionary preconditions of extended longevity, one can compare the key life-history events and age related changes in body conditions in related species with different ecological speciation. Cricetid rodents possessing a wide spectrum of adaptive forms with different life history strategies are an excellent model for this purpose. We compared median and maximum longevity, life expectancy, temporal distribution of reproductive efforts, and age related dynamic of several physical condition indexes: body mass, muscle strength, locomotor activity and frequency of vertical postures in open field tests in five species of this family. Studied species vary both in maximum (from three years in steppe lemmings (Lagurus lagurus) to more than six years in mole voles (Ellobius talpinus) and rock voles (Alticola strelzovi) and median longevity (from less than one year in Lagurus lagurus to 2.8 years in rock vole Alticola tuvinicus). Both species with high maximum longevity – Ellobius talpinus and Alticola strelzovi face chronic hypoxia in their native environment. The total amount of litters born varied from three in A. strelzovi to 13 in Phodopus sungorus. Species under study also differed in age-related dynamics of physical conditions. Among the studied species, the subterranean E. talpinus has the highest maximum longevity with relatively long duration of reproductive period and only weak age-related deterioration in body conditions, i.e. shares many aspects of the life history strategy of such a specialized group as the Bathyergidae family.
{"title":"Age-related dynamics of reproductive activity and physical conditions in Cricetidae of different ecological speciation (Rodentia)","authors":"Evgenij Novikov","doi":"10.37520/lynx.2022.009","DOIUrl":"https://doi.org/10.37520/lynx.2022.009","url":null,"abstract":"To understand the evolutionary preconditions of extended longevity, one can compare the key life-history events and age related changes in body conditions in related species with different ecological speciation. Cricetid rodents possessing a wide spectrum of adaptive forms with different life history strategies are an excellent model for this purpose. We compared median and maximum longevity, life expectancy, temporal distribution of reproductive efforts, and age related dynamic of several physical condition indexes: body mass, muscle strength, locomotor activity and frequency of vertical postures in open field tests in five species of this family. Studied species vary both in maximum (from three years in steppe lemmings (Lagurus lagurus) to more than six years in mole voles (Ellobius talpinus) and rock voles (Alticola strelzovi) and median longevity (from less than one year in Lagurus lagurus to 2.8 years in rock vole Alticola tuvinicus). Both species with high maximum longevity – Ellobius talpinus and Alticola strelzovi face chronic hypoxia in their native environment. The total amount of litters born varied from three in A. strelzovi to 13 in Phodopus sungorus. Species under study also differed in age-related dynamics of physical conditions. Among the studied species, the subterranean E. talpinus has the highest maximum longevity with relatively long duration of reproductive period and only weak age-related deterioration in body conditions, i.e. shares many aspects of the life history strategy of such a specialized group as the Bathyergidae family.","PeriodicalId":122460,"journal":{"name":"Lynx new series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125828313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：