Search results for "bat"
showing 10 items of 4075 documents
Alien Species of EU Concern in Romania
2017
AbstractOf the 37 species of the European Union concern eight are already present and two present a future potential risk for Romania. This paper brings updated information regarding these species in Romania. The presence of eight invasive alien species of concern to the European Union have already been recorded in Romania: two plant speciesCabomba carolinianaandHeracleum sosnowskyi, two crustaceansOrconectes limosusandEriocheir sinensis, two fish speciesPseudorasbora parvaandPerccottus glenii, one reptileTrachemys scriptaand one mammalMyocastor coypus. Other two species of Union concern (Lithobates catesbeianusandProcyon lotor) may soon become invaders in Romania. We emphasize the urgent n…
la prospection systématique d’un fond de rivière : l’exemple du Doubs
2020
La présentation des méthodes mises en œuvre et des résultats obtenus à l’occasion d’une opération de prospection subaquatique systématique menée sur la rivière Doubs, en amont de Verdun-sur-le-Doubs (Saône-et-Loire), illustre en grandeur réelle l’intérêt de la démarche adoptée, fondée sur des principes simples, dans la perspective d’un inventaire systématique du patrimoine fluvial immergé. La diversité des vestiges découverts et leur répartition sur la longue durée en soulignent la pertinence mais également, s’il en était encore besoin, la réalité du formidable potentiel archéologique que recèlent les cours d’eau. The presentation of the methods used and results obtained during a systematic…
Are sacred caves still safe havens for the endemic bats of Madagascar?
2018
AbstractDespite conservation discourses in Madagascar increasingly emphasizing the role of customary institutions for wildlife management, we know relatively little about their effectiveness. Here, we used semi-structured interviews with 54 adults in eight villages to investigate whether sacred caves and taboos offer conservation benefits for cave-dwelling bats in and around Tsimanampetsotsa National Park, south-west Madagascar. Although some caves were described as sites of spiritual significance for the local communities, most interviewees (c. 76%) did not recognize their present-day sacred status. Similarly, only 22% of the interviewees recognized taboos inhibiting bat hunting and consum…
Optimization of Synthetic Media Composition for Kluyveromyces marxianus Fed-Batch Cultivation
2021
The Kluyveromyces marxianus yeast recently has gained considerable attention due to its applicability in high-value-added product manufacturing. In order to intensify the biosynthesis rate of a target product, reaching high biomass concentrations in the reaction medium is mandatory. Fed-batch processes are an attractive and efficient way how to achieve high cell densities. However, depending on the physiology of the particular microbial strain, an optimal media composition should be used to avoid by-product synthesis and, subsequently, a decrease in overall process effi-ciency. Thus, the aim of the present study was to optimise the synthetic growth medium and feeding solution compositions (…
Influence of warming temperatures on coregonine embryogenesis within and among species
2021
The greatest response of lakes to climate change has been the increase in water temperatures on a global scale. The responses of many lake fishes to warming water temperatures are projected to be inadequate to counter the speed and magnitude of climate change, leaving some species vulnerable to decline and extinction. We experimentally evaluated the responses of embryos from a group of cold, stenothermic fishes (Salmonidae Coregoninae) - within conspecifics across lake systems, between congeners within the same lake system, and among congeners across lake systems - to a thermal gradient using an incubation method that enabled global comparisons. Study groups included cisco (Coregonus artedi…
Social information use about novel aposematic prey is not influenced by a predator’s previous experience with toxins
2019
Aposematism is an effective antipredator strategy. However, the initial evolution and maintenance of aposematism are paradoxical because conspicuous prey are vulnerable to attack by naive predators. Consequently, the evolution of aposematic signal mimicry is also difficult to explain. The cost of conspicuousness can be reduced if predators learn about novel aposematic prey by observing another predator's response to that same prey. On the other hand, observing positive foraging events might also inform predators about the presence of undefended mimics, accelerating predation on both mimics and their defended models. It is currently unknown, however, how personal and social information combi…
From habitat use to social behavior: natural history of a voiceless poison frog, Dendrobates tinctorius
2019
AbstractDescriptive studies of natural history have always been a source of knowledge on which experimental work and scientific progress rely. Poison frogs are a well-studied group of small Neotropical frogs with diverse parental behaviors, distinct calls, and bright colors that warn predators about their toxicity; and a showcase of advances in fundamental biology through natural history observations. The dyeing poison frog, Dendrobates tinctorius, is emblematic of the Guianas region, widespread in the pet-trade, and increasingly popular in research. This species shows several unusual behaviors, such as the lack of advertisement calls and the aggregation around tree-fall gaps, which remain …
Why aren't warning signals everywhere? : On the prevalence of aposematism and mimicry in communities
2021
Warning signals are a striking example of natural selection present in almost every ecological community - from Nordic meadows to tropical rainforests, defended prey species and their mimics ward off potential predators before they attack. Yet despite the wide distribution of warning signals, they are relatively scarce as a proportion of the total prey available, and more so in some biomes than others. Classically, warning signals are thought to be governed by positive density-dependent selection, i.e. they succeed better when they are more common. Therefore, after surmounting this initial barrier to their evolution, it is puzzling that they remain uncommon on the scale of the community. He…
Evaluating the potential for evolutionary mismatch in Batesian mimics: A case study in the endangered smooth snake (Coronella austriaca)
2018
Many harmless organisms gain a survival advantage by mimicking venomous species. This is the case of the endangered smooth snake (Coronella austriaca), which mimics venomous vipers. Although this may protect the smooth snake against most of its natural predators, it may render them at greater risk of mortality from humans, who are more inclined to kill species, such as vipers, that they consider dangerous. This may cause an evolutionary mismatch, whereby humans may counteract the natural advantage of mimicry. We explore this possibility of evaluating the willingness of humans to kill smooth snakes versus the adder (Vipera berus), as well as their ability to discern them in the Åland Islands…
Exploring how social interactions influence regulators and innovators: The case of regulatory sandboxes
2020
Like incubators, regulatory sandboxes constitute a prominent mechanism to enable entrepreneurial activities that guide financial technology (FinTech) firms through regulatory frameworks in the financial industry. Because they are new, there is a lack of research on regulatory sandboxes; most studies have investigated legal aspects while overlooking the management perspective. To address this gap, this paper builds on incubation research studies to explore how social interactions within regulatory sandboxes influence the practices of regulators and regulatees, using social capital theory. An exploratory-abductive approach is adopted, using data collected from 16 semi-structured interviews. T…