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435. Demography of adults of the Marsh fritillary butterfly, Euphydryas aurinia (Lepidoptera: Nymphalidae) in the Czech Republic: Patterns across sites and seasons

Creator:
Kamil Zimmermann, Blažková, Pavla, Čížek, Oldřich, Frič, Zdeněk, Hůla, Vladimír, Kepka, Pavel, Novotný, David, Slámová, Irena, and Martin Konvička
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, entomologie, Česko, Czechia, Lepidoptera, Nymphalidae, Euphydryas aurinia, Marsh fritillary, butterfly conservation, demography, density dependence, grasslands, local dynamics, metapopulation, 2, and 59
Language:
English
Description:
The Marsh fritillary (Euphydryas aurinia) (Lepidoptera: Nymphalidae) has declined across Europe, including the Czech Republic. Current conservation strategies rely on prevention of habitat loss and degradation, and increase in habitat quality and connectivity via promoting traditional grassland management. The population structure and adult demography parameters of a single population was investigated for eight years (single system), and of all the known Czech populations (multiple populations) for a single year, using mark-recapture. There was substantial variation in the patterns of adult demography, both among years in the single system and among the multiple populations in a single year. In the single system, the date of the first flight of an adult varied by 18 days over the 8 years and total annual numbers varied with a coefficient of variation of 0.40 (females fluctuating more than males). The average density was ca 80 adults/ha. The population size displayed density-dependence, i.e. decreased following years with high adult numbers, with an equilibrium density of 90 individuals/ha. The average density of the multiple populations was ca 120 individuals/ha. The estimated total population for the Czech Republic was 25,000 individuals (17,000 males / 8,000 females) in 2007, which does not indicate an imminent threat of extinction. The regional persistence of E. aurinia is likely to depend on re-colonisation of temporarily vacant sites by dispersing individuals, facilitated by local shifts in adult flight phenology to that better adapted to local conditions. and Kamil Zimmermann, Pavla Blazkova, Oldrich Cizek, Zdenek Fric, Vladimir Hula, Pavel Kepka, David Novotny, Irena Slamova, Martin Konvicka.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

436. Demography of the endangered butterfly Euphydryas aurinia (Lepidoptera: Nymphalidae): A case study of populations in sub-Mediterranean dry calcareous grasslands

Creator:
Jugovic, Jure, Uboni, Costanza, Zupan, Sara, and Lužnik, Martina
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
motýli, babočkovití, demografie, grasslands, butterflies, Nymphalidae, demography, Slovinsko, Slovenia, Euphydryas aurinia, mark-release-recapture, movement, nectar plants, metapopulation, 2, and 59
Language:
English
Description:
We studied a population of the regionally endangered marsh fritillary butterfly Euphydryas aurinia inhabiting a system of loosely connected dry calcareous grasslands in sub-Mediterranean Slovenia. Our goal was to set the basis for a long-term monitoring of this butterfly in four meadows using mark-release-recapture (MRR). We determined its demographic parameters, dispersal, behaviour and utilization of nectar plants in different quality patches. Total population size was estimated to be approximately 347 males (95% confidence interval: 262-432) and 326 females (95% confidence interval: 250-402), with an unbiased sex ratio. The average lifespans were 6.3 and 8.6 days, respectively. Daily population sizes followed a parabola with marked protandry. Both sexes were relatively highly mobile with both occasionally moving over half a kilometre. The spatial distribution of animals seemed to be associated with patch size, host plant densities and nectar sources, resulting in much higher population densities in the largest patch. Adult behaviour differed between the sexes, with females resting more and flying less than males. Behaviour also changed during daytime and with the progression of the season. Adults were confirmed to be opportunistic feeders, since as many as ten nectar sources were detected. We conclude that demographic parameters differ greatly among regions and habitats, thus conservation aims should be planned accordingly. Although the population studied is apparently in good condition, there are threats that may hamper the long-term persistence of the species in this area: succession, intensification of mowing and overgrazing., Jure Jugovic, Costanza Uboni, Sara Zupan, Martina Lužnik., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

438. Density-invariant dispersion indices and fixed precision sequential sampling plans for the peach twig borer Anarsia lineatella (Lepidoptera: Gelechiidae)

Creator:
Damos, Petros
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
motýli, makadlovkovití, vzorkování, butterflies, Gelechiidae, sampling, Anarsia lineatella, spatial dispersion, integrated pest management, moth, peach production, 2, and 59
Language:
English
Description:
Estimating the spatial dispersion of pest arthropods is crucial for the development of reliable sampling programs and one of the main components of integrated pest management. The natural spatial distribution of a population of a species may be random, uniform, or aggregated and can be so classified based on calculation of variance to mean relations and related dispersion indices. In this work some classical density-invariant dispersion indices and related regression models are used for the first time to quantify the spatial dispersion of an important peach pest Anarsia lineatella Zeller (Lepidoptera: Gelechiidae) and construct fixed precision sequential sampling schemes. Taylor's power law, Iwao's patchiness regression and Nachman's model were used to analyse the damage to peaches caused by A. lineatella. All three regression models fit the data well, although the results indicate that Iwao's patchiness model provides a better description of the relationship between variance and mean density. Taylor's b and Iwao's b regression indices were both significantly smaller than 1, indicating that the distribution of individuals was uniform rather than random or aggregated. According to Green's and Kuno's models, the minimum sample size at the precision level of 0.2 varies from 3 samples, when total population density is more than 3 larvae/sample, to 10 samples, when population density is between 1 and 2 larvae/sample. Kuno's fixed sampling plan indicates that a small number of samples (i.e., 3-10 branches with fruit) is sufficient to estimate the mean population density of A. lineatella larvae with a precision of 0.2. The Resampling for validation of sampling plans (RVSP) method confirmed that the average level of precision of the fixed sequential plans matched the desired precision in most cases. The sampling plan presented here provides a level understanding of A. lineatella spatial ecology suitable for pest manage, Petros Damos., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

439. Depilation increases while hairiness decreases the risk of drowning: a hitherto unappreciated survival role of setae in woolly bear caterpillars of the moth Lemyra imparilis (Lepidoptera: Noctuoidea: Erebidae)

Creator:
Meyer-Rochow, V. Benno
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, motýli, butterflies, Lepidoptera, Erebidae, Lemyra imparilis, insect setae, cuticle, wettability, floating, 2, and 59
Language:
English
Description:
This note aims to put on record a hitherto unreported function of caterpillar setae supplementary to those already known. When woolly bear caterpillars of the moth Lemyra imparilis (Butler) have their body hairs removed and are dropped into a bucket of water from a height of 30 cm, they sink immediately. Caterpillars, however, with an intact coat of hairs usually float. This hitherto unreported role of caterpillar setae as life-rafts should depend on a high contact angle θe, and thus on the position, density and dimensions of the hairs. An SEM examination of the surface structure of the setae revealed a system of fine grooves and small distally pointing barbs on the hair shaft, which can trap air to support the weight of the insect. Insect setae generally and body hairs of caterpillars in particular are known to possess many functions, but a role as life-rafts for caterpillars in danger of drowning can now be added to the list of possible uses of body hairs., V. Benno Meyer-Rochow., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

440. Depressed cardiac contractility and its postnatal development in rats after chemical sympathectomy

Creator:
Jitka Švíglerová, Jitka Kuncová, Lukáš Nalos, Jana Slavíková, and Milan Štengl
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Biochemie. Molekulární biologie. Biofyzika, fyziologie, neuropeptidy, srdce, potkan, physiology, neuropeptids, heart, Rattus norvegicus, chemical sympathectomy, contraction, norepinephrine, 2, and 577
Language:
English
Description:
This study sought to evaluate whether consumption of polyphenol extract from Cognac (CPC) modulates platelet activation and cardiovascular reactivity in rats. Male Wistar rats were treated daily for 4 weeks by intra-gastric gavage receiving CPC at 80 mg/kg/day or vehicle (5 % glucose). Platelet adhesion and aggregation in response to different activators were assessed. Cardiac and vascular reactivity in response to various agonists as well as NO measurement by electron paramagnetic resonance technique were investigated in isolated heart and thoracic aorta. Oral administration of CPC decreased platelet aggregation induced by ADP but not by collagen. CPC did not affect adhesion to collagen. The chronotropic but not the inotropic response to isoprenaline was reduced without alteration of NO production in hearts from CPC-treated rats. CPC treatment did not affect ex vivo relaxation to acetylcholine nor NO content of rat aorta. CPC did not significantly alter the response to phenylephrine in aorta despite the participation of endothelial vasoconstrictor products. In summary, chronic treatment with CPC has no impact on ex vivo vascular and cardiac reactivity; however, it reduced heart work and platelet aggregation. These data suggest the existence of compounds in Cognac that may decrease the risk of coronary thrombosis and protect against some cardiac diseases., J. Švíglerová, J. Kuncová, L. Nalos, J. Slavíková, M. Štengl., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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