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412. Motorway as a barrier to dispersal of the threatened dragonfly Sympetrum depressiusculum (Odonata: Libellulidae): consequence of mortality or crossing avoidance?
- Creator:
- Šigutová, Hana, Filip Harabiš, Hykel, Michal, and Aleš Dolný
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, vážky, chování živočichů, úmrtnost, Odonata, animal behavior, mortality, Libellulidae, dispersal barrier, dragonflies, habitat fragmentation, 2, and 59
- Language:
- English
- Description:
- Infrastructure is one of the main causes of landscape fragmentation, which results in isolation and loss of populations. Although the negative effect of roads on insects is well documented, only a minority of studies has focused on roads in the context of barriers to dispersal. Flying species in particular have been neglected. We investigated the effect of a four-lane motorway as a barrier to the movement of an isolated population of the threatened dragonfly Sympetrum depressiusculum in an agricultural landscape in Central Europe. Generalized additive models were used to assess the motorway's effect on (i) the distribution of adult dragonflies in patches of terrestrial habitat surrounding their natal site, and (ii) individual flight behaviour (i.e. willingness or unwillingness to cross the motorway). Movement patterns of marked adults throughout the landscape were also investigated. During one season, significantly fewer adults were found at patches located on the far side of the motorway, indicating it has a barrier effect. Observations on flight behaviour revealed no apparent effect of the motorway. The possible barrier effect for the species studied was therefore presumed to be a consequence of road mortality. Our results indicate that the motorway may influence the dispersal of this threatened species of dragonfly, which is a habitat specialist with particular requirements for its terrestrial environment. Negative effects on other species with similar behaviour and strategy can be presumed. When establishing new habitats, carrying out reintroductions or translocations, it is necessary to consider that roadways may reduce population size and affect population dynamics by limiting dispersal., Hana Šigutová, Filip Harabiš, Michal Hykel, Aleš Dolný., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
413. Motýli s průhlednými křídly
- Creator:
- Jiří Křížek
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, motýli, 2, and 59
- Language:
- Czech
- Description:
- This contribution presents butterflies with wings on which scales are partially or fully absent, as well as various forms of their cryptic appearance and mimicry and George O. Krizek.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
414. Motýlové: soustavný popis motýlů v zemích koruny české žijících, jakož i housenek a kukel jejich, s připojeným návodem, kdy a kde chytati motýle, sbírati kukly, housenky a vajíčka a kterak upravovati je pro sbírky
- Creator:
- Exler, Karel
- Publisher:
- I. L. Kober
- Format:
- print, text, regular print, and 208 s. : 20 barev. obr. tab. ; 8°
- Type:
- model:monograph and TEXT
- Subject:
- 59, 2, motýli, housenky, kukly, and Zoologie
- Language:
- Czech
- Description:
- pro učitelstvo, žactvo středních škol a zvláště sběratele motýlů napsal Karel Exler, S 25 rytinami a 20 tab. obsah. 289 obrazů motýlů a housenek dle přírody vyobrazených, and Converted from MODS to DC version 1.8 (EE patch 2018/05/24)
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
415. Movement, demography and behaviour of a highly mobile species: A case study of the black-veined white, Aporia crataegi (Lepidoptera: Pieridae)
- Creator:
- Jugovic, Jure, Črne, Mitja, and Lužnik, Martina
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, běláskovití, demografie, Pieridae, demography, Lepidoptera, Aporia crataegi, mark-release-recapture, movement, nectar plants, 2, and 59
- Language:
- English
- Description:
- We studied the demography, movement, behaviour and choice of nectar plants by adults of Aporia crataegi. This study was done in a dense network of different types of habitats (total size of study area 16.26 ha) from open landscape to shrubland, the latter being a result of abandonment of traditional agricultural practices such as extensive mowing and grazing. Total population size was estimated to be approximately 1700 and 2700 for females and males, respectively. Median and maximum distances moved by males were 134 and 3493 m, and by females 138 and 3165 m, respectively. The average lifespan was ca. 7.1 and 7.5 days, with maximum recorded lifespans of 21 and 17 days for males and females, respectively. The greater capture probability recorded for males indicates their high activity, as they spend most of their time in flight patrolling and searching for mates. A parabolic recruitment curve and protandry were also recorded. Both sexes are highly mobile. The spatial distribution of both sexes was roughly similar. The adult behaviour differed in different habitats, with more time spent feeding and resting when nectar plants were plentiful and more time spent flying when they were rare. Although adults utilized nine nectar sources, only two were recorded in over 80% of all the feeding occasions. In order to re-establish open grassland with some shrubland, traditional and mosaic management of the landscape should be revived at least to some extent., Jure Jugovic, Mitja Črne, Martina Lužnik., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
416. Mravenec lužní - mýty a fakta
- Creator:
- Jiří Schlaghamerský and Lenka Petráková
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, entomologie, mravencovití, entomology, ants, 2, and 59
- Language:
- Czech
- Description:
- Mravenec lužní (Liometopum microcephalum) dosahuje na jižní Moravě (v jihovýchodních Čechách) severozápadní hranice svého rozšíření, a druhu se tak dostávalo velké pozornosti mezi českými přírodovědci. Mnohé informace publikované v literatuře nebo na internetu však jsou spíše mýty než fakta. O areálu druhu se často uvádí, že se rozkládá od Iberského poloostrova do východní Evropy a nejzápadnější části Asie, někdy dokonce až na ruský Dálný východ. Ve skutečnosti neexistují žádné doklady o historickém ani současném výskytu mravence lužního na západ od Alp (severní Itálie). Populace na Dálném východě byla již před dlouhou dobou odlišena jako samostatný druh. Článek detailně popisuje historické a současné rozšíření tohoto mravence na jižní Moravě. Ačkoli jde o nejsevernější populaci druhu, populace na Ukrajině a v Rusku dosahují téměř stejné zeměpisné šířky. Mravenec lužní kolonizuje staré, ale živé stromy s dutinami, zpravidla duby, v lesích i mimo les. Na severní hranici svého areálu dává jednoznačně přednost lužním stanovištím, na jihu je preferuje mnohem méně. Jasné doklady uváděné ochrany hnízdních stromů mravenčími koloniemi scházejí. Přes protichůdné názory publikované v literatuře tvoří trofobióza významnou součást potravní strategie druhu, ale stanovení důležitosti jednotlivých složek potravy stále chybí. Druh se vyznačuje jasným polymorfismem dělnic, ale stupeň polymorfismu se liší mezi koloniemi, mění se v průběhu roku a také závisí na podmínkách prostředí, jako je přítomnost silných kompetitorů. Mnohé otázky týkající se biologie a ekologie mravence lužního zatím zůstávají nezodpovězeny., The arboricolous ant Liometopum microcephalum, which reaches the north-western edge of its range in South Moravia (south-eastern Czechia), has been receiving substantial attention by Czech naturalists. However, many pieces of information presented in the literature or on the internet are more myth then fact. Its range is often reported to reach from the Iberian Peninsula to Eastern Europe and western-most Asia, sometimes even to the Russian Far East. In fact, there is no evidence of its historic or present occurrence west of the Alps (northern Italy). The Far Eastern population has been recognized as a separate species a long time ago. The historic and current range in South Moravia is described in detail. Although being indeed the northern-most population of the species, populations in the Ukraine and Russia reach almost the same latitude. Old but living trees with cavities, mostly oaks, are colonized both in and outside of forests. There is a clear preference for alluvial habitats in the northern part of its range, much less so in the south. There is hardly any evidence for the reported protection of nest trees by its ant colonies. Despite contrary opinions published, trophobiosis is an important part of the species’ foraging behaviour, but an assessment of the importance of different components of its diet is still lacking. Worker polymorphism is apparent but its degree varies among colonies and changes in the course of the year and also mirrors environmental variables such as the presence of strong competitors. Many questions regarding the species’ biology and ecology remain open., and Jiří Schlaghamerský, Lenka Petráková.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
417. Mšice republiky československé, zvláště okolí ostravského
- Creator:
- Drastich, Ludvík
- Publisher:
- Čsl. společ. entomologická
- Format:
- print, text, regular print, and 40 s. : obr. ; v. 8°
- Type:
- model:monograph and TEXT
- Subject:
- Zoologie, mšice, systematika, výskyt, Ostrava (Česko : oblast), 595.7, 2, 59, and UL01
- Language:
- Czech
- Description:
- MUC. Ludvík Drastich
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
418. Muchničky - trapiči i ohrožené druhy
- Creator:
- Brúderová, Tatiana and Matúš Kúdela
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, entomologie, hematofágní hmyz, entomology, bloodsucking insects, 2, and 59
- Language:
- Czech
- Description:
- Muchničky jsou známy v mnoha oblastech jako trapiči člověka i dobytka, ale také jako přenášeči parazitárních onemocnění, z nichž nejvýznamnější je říční slepota. Muchnička Simulium colombaschense byla v minulosti považována za jeden z nejnebezpečnějších druhů v rámci čeledi, protože na následky napádaní samičkami tohoto druhu uhynuly na Balkánském polostrově desetitisíce kusů dobytka. V současnosti se však zdá, že může být považována za ohrožený druh, především v důsledku regulace velkých řek. Podle předběžných výsledků analýzy polytenních chromozomů představuje S. colombaschense komplex druhů s menšími areály. Typová lokalita druhu S. colombaschesne byla zničena po přehrazení Dunaje v oblasti Železných vrat a následně z této oblasti postupně zmizelo i S. colombaschense. Podobný osud může v blízké době postihnout, nebo už postihl také další blízce příbuzné druhy z tohoto komplexu., Black flies (Simuliidae) are known in several areas as pests to humans and cattle, but also as transmitters of parasitic diseases, among which river blindness is the most important. In the past, the black fly Simulium colombaschense was considered to be one of the most dangerous species of the family, because it caused the death of tens of thousands of cattle in the Balkan peninsula. However, at present it seems that it can be considered an endangered species, especially due to large river regulation. Moreover, according to preliminary analysis of polytene chromosomes S. colombaschense is a complex of species with smaller distribution areas. The type locality of S. colombaschense was destroyed after the Danube was dammed in the Iron Gate region and subsequently S. colombaschense disappeared from this area. In the near future the same might possibly happen, or has already happened as to other species from this complex., and Tatiana Brúderová, Matúš Kúdela.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
419. Muga silkworm, Antheraea assamensis (Lepidoptera: Saturniidae) – an overview of distribution, biology and breeding
- Creator:
- Tikader, Amelendu, Vijaydan, Kunjupillai, and Saratchandra, Beera
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Lepidoptera, Saturniidae, muga silkworm, Antheraea assamensis, rearing, improvement, disease, grainage, 2, and 59
- Language:
- English
- Description:
- Muga silkworm (Antheraea assamensis Helfer) is endemic to Assam and adjoining areas in North-Eastern India, and naturally produces golden silk. From time immemorial, many ethnic and tribal groups have produced muga silk. Muga silkworms are mostly wild unlike the mulberry silkworm, which is completely domesticated. The muga silkworm is a single species with little genetic variation among populations, survives harsh climatic conditions and is subject to various diseases, pests and predators. Due to the high incidence of disease and natural enemies, and variations in climatic conditions, the production of muga silk has recently declined dramatically. In order to improve the productivity of this silkworm it is important to have a better knowledge of both its host plants and biology. Lack of knowledge of its genetics and host plants is a major bottleneck. This paper reviews various aspects of muga silkworm culture, including the availability of different populations, and methods used to select for improvement in survival, cocoon yield, disease resistance, conservation and egg production., Amelendu Tikader, Kunjupillai Vijayan, Beera Saratchandra., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
420. Multicoloniality in the highly polygynous ant Crematogaster pygmaea (Formicidae: Myrmicinae)
- Creator:
- Hamidi, Rachid, Debout, Gabriel, Heredia, Ana, Fournier, Denis, Quinet, Yves, and De Biseau, Jean-Christophe
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Formicidae, Myrmicinae, multicoloniality, polygyny, polydomy, Crematogaster pygmaea, context-dependent nestmate discrimination, 2, and 59
- Language:
- English
- Description:
- In social insects, the high variability in the number of queens per colony raises fundamental questions about the evolution of altruism. It is hypothesized, for instance, that nestmate recognition should be less efficient in polygynous than in monogynous colonies because the presence of several breeders increases the diversity of genetically determined recognition cues, leading to a less specific colonial signature. Recent studies, however, have shown that the link between the number of queens in a colony and the recognition abilities of its members is more complex than previously suggested. Here, we studied intraspecific aggression, diversity of potential recognition cues and genetic structure of colonies in the highly polygynous ant Crematogaster pygmaea. Our results reveal that workers of this species are clearly aggressive towards non-nestmates in field experiments but not in more artificial bioassays conducted in Petri dishes, underscoring the importance of context-dependent aspects of the assessment of nestmate recognition. Behavioural, genetic and chemical data show that C. pygmaea is a multicolonial species, forming spatially restricted and well-defined entities. Therefore, the postulated negative correlation between recognition ability of workers and queen number in a colony is not supported by the results of this study., Rachid Hamidi ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public