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12. Food caching by a Eurasian otter
- Creator:
- Lanszki, József, Mórocz, Attila, and Conroy, Jim W. H.
- Type:
- article and TEXT
- Subject:
- Lutra lutra, cached food, behaviour, spraint analysis, and Danube
- Language:
- English
- Description:
- In early spring of 2007, unusual feeding behaviour was observed for the Eurasian otter (Lutra lutra) when a cache of toads (n = 18), black bullheads (n = 2) and great diving beetles (min. 58 ind.) were found in a hollow tree-trunk on the shores of an oxbow lake near the River Danube. Spraint analysis identified the primary food of otters in the area to be fish, with non-fish (buffer) prey of very low importance. As the otter consumed almost exclusively fish, and appeared to store mainly buffer food items, this may indicate that either preferred fish were less available (limited) or that non-fish items were relatively more abundant for a short period during the mild ‘cold’ winter and spring period. The otter had abandoned this particular cache. Food caching is an important dietary adaptation for many species, providing readily available food during periods when fresh food may be difficult to find.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
13. Foraging in a complex environment - semiochemicals support searching behaviour of the seven spot ladybird
- Creator:
- Pettersson, Jan, Ninkovic, Velemir , Glinwood, Robert , Birkett, Michael A., and Pickett, John A.
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, ladybird, semiochemical, behaviour, habitat, and forage(ing)
- Language:
- English
- Description:
- Knowledge of semiochemically-mediated behavioural mechanisms of the seven-spot ladybird, Coccinella septempunctata L., is limited but sufficient to encourage further studies in the behavioural ecology of this well known insect. Recent findings on semiochemicals are discussed in relation to the main traits in the ecology of C. septempunctata. A putative autumn aggregation pheromone, and effects of allelobiotic plant interactions on habitat preferences of adults are reported. Mechanisms for interaction between an aphid alarm pheromone and plant substances are described, and the kairomonal functions of volatiles from C. septempunctata on the parasitoid Dinocampus coccinellae (Schrank) (Hymenoptera: Braconidae) are discussed. Considering the polyphagous diet of C. septempunctata, investigations on the importance of associative learning of chemical cues in foraging behaviour, and further studies on interactions with other third trophic level organisms will provide interesting lines of research.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14. importance of breeding density and breeding synchrony for paternity assurance strategies in the lesser grey shrike
- Creator:
- Krištín, Anton, Hoi, Herbert, Valera, Francisco, and Hoi, Christine
- Type:
- article and TEXT
- Subject:
- behaviour, mating strategy, copulation frequency, intruder rate, and Lanius minor
- Language:
- English
- Description:
- Breeding density and breeding synchrony have been reported to influence the intensity of sperm competition although results obtained so far are not conclusive. In this study we examine the investment of male lesser grey shrike (Lanius minor) into paternity guards in relation to breeding synchrony and breeding density. Male shrikes perform a double strategy to ensure paternity. They copulate frequently, mainly after territorial intrusions by other males, and guard their mates throughout the whole fertile phase. Our results indicate that, the two socio- ecological factors investigated, indirectly affect extra-pair behaviour in LGS’s. Males seem to be constrained by the frequency of intrusions by neighbouring males and this risk is associated with laying synchrony. The risk of intrusions depends on the timing and overlap of breeding attempts and males adjust their investment to paternity assurance accordingly. Furthermore, females seem to alter their egg laying patterns to minimise synchrony in situations where they find themselves in dense breeding situations. This is indicated by the negative correlation between breeding density and breeding synchronization. Extra-pair paternity, however, was not detected in our population. Thus the rate of extra-pair paternity is not necessarily an adequate measure to identify the influence of socio-ecological factors on male and female mating strategies.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
15. Influence of chronic toxoplasmosis on some human personality factors
- Creator:
- Flegr, J. and Hrdý, I.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Toxoplasma, toxoplasmosis, behaviour, personality factors, Cattell’s questionnaire, and manipulation hypothesis
- Language:
- English
- Description:
- An effect of parasites on host behaviour was tested on the toxoplasma-human model. Three hundred and thirty-eight (338) people were assessed with Cattell’s personality questionnaire and then tested for Toxoplasma gondii infection with a delayed type hypersensitivity test for Toxoplasma. A highly significant correlation between chronic toxoplasmosis and two personality factors (G- Low Superego Strength and L- Protension) was found (p = 0.0032 and 0.0020, respectively). A correlation of the intensity of the personality factor-shifts with the duration of the infection (estimated from antibody titer) suggests that toxoplasmosis induces the shift in human personality, rather than the personality factors G and I. influence an acquisition rate of Toxoplasma gondii infection.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
16. Larval morphology of Scydmaenus tarsatus and S. hellwigii, with notes on feeding behaviour and a review of the bibliography on the preimaginal stages of ant-like stone beetles (Coleoptera: Staphylinidae: Scydmaeninae)
- Creator:
- Jaloszynsky, Pawel and Kilian, Aleksandra
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Coleoptera, Staphylinidae, Scydmaeninae, Scydmaenini, Scydmaenus, Palaearctic, larval morphology, behaviour, feeding, 2, and 59
- Language:
- English
- Description:
- Morphology of mature larvae of two Central European species of Scydmaenus Latreille is described and illustrated: S. (s. str.) tarsatus Müller & Kunze and S. (Cholerus) hellwigii (Herbst). Inaccuracies in previous descriptions of S. tarsatus are discussed and the following combination of characters is defined as diagnostic for Scydmaenus: epicranial sutures reaching posteromedian margins of antennal insertions; presence of a single pair of stemmata and epicranial supraantennal pits; anterior row of subtriangular teeth on epipharynx; mandibles falciform and without mesal teeth; antennomere 3 rudimentary; antennal sensory appendage subconical and asymmetrical; maxilla with galea and lacinia; labium strongly constricted between mentum and prementum; thoracic tergites undivided along midline; head capsule, thoracic tergites, laterotergites and abdominal segments except sternite 1 densely setose; thoracic sternites and abdominal sternite1 largely asetose; and lack of urogomphi. We also describe the feeding behaviour of immature S. tarsatus and demonstrate for the first time that Scydmaeninae larvae can feed on live springtails and not armoured mites. In the introduction we provide a summary of the literature on all hitherto known preimaginal stages of Scydmaeninae., Pawel Jaloszynski, Aleksandra Kilian., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17. Local variability in the diet of Daubenton's bat 'Myotis daubentonii in a lake landscape of northern Germany
- Creator:
- Nissen, Henning, Krüger, Frauke, Fichtner, Andreas, and Sommer, Robert S.
- Type:
- article, model:article, and TEXT
- Subject:
- foraging, hunting, behaviour, trawling, aerial hawking, and prey diversity
- Language:
- English
- Description:
- Daubenton’s bat Myotis daubentonii is one of the most common bat species of Europe, hunting its prey in the surroundings of water bodies, with different microhabitats. To explore the local adaptability to different environmental conditions, we compared the diet of Daubenton’s bats at four different sites in a lake landscape in northern Germany with a main focus on prey diversity. Bats were caught (n = 85) in mist nets for collecting individual faecal pellets (n = 276). Pellets were dissected and the occurrence of identifiable pieces of each prey group was evaluated and grouped in five different frequency groups. We found 17 different groups of arthropods among the prey, with a clear dominance of Chironomidae and Trichoptera. There were significant differences among the sampling sites in prey diversity but not in prey richness.The changes in prey diversity were associated with sample sites. We conclude that on a local scale there is low variability in diet of Daubenton’s bat caused by hunting in various habitat structures in the surroundings of water bodies. Our results highlight the ecological flexibility of M. daubentonii, which could be an explanation for the commonness of M. daubentonii across Europe in comparison to the rather rare pond bat (Myotis dasycneme), which has similar habitats and main prey group preferences.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
18. Mating activity of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) in nature
- Creator:
- Honěk, Alois , Martinková, Zdenka , and Brabec, Marek
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Heteroptera, Pyrrhocoridae, Pyrrhocoris apterus, firebug, behaviour, copulation, daily changes, seasonal changes, and sperm depletion
- Language:
- English
- Description:
- The mating behaviour of Pyrrhocoris apterus in the laboratory is well studied, but little is known about it under natural conditions. In natural populations in Central Europe, overwintered adults start copulating in March and continue until their death. Caged females, kept under natural conditions in the permanent presence of males, copulated repeatedly. Their mating activity increased sharply until early April, then very slowly until the end of June and then declined as the females die-off. Half of copulations were short (< 5 h) and only 9% were longer than 1 day. By contrast, in natural populations, mating activity (percentage of individuals involved in copula) reached its maximum in April and then decreased until early July, when the overwintered adults die. The decline in mating frequency (percentage of adults involved in copula) was associated with a decrease in the availability of receptive females towards the end of the mating period. For a female, repeated copulation is necessary because sperm is nearly depleted after insemination of 3-5 egg batches.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
19. Physiological state of female and light intensity affect the host-plant selection of carrot psyllid, Trioza apicalis (Hemiptera: Triozidae)
- Creator:
- Nissinen, Anne, Kristoffersen, Lina, and Anderbrant, Olle
- Type:
- article, model:article, and TEXT
- Subject:
- Triozidae, Trioza apicalis, host-plant selection, Daucus carota, Picea abies, light intensity, light gradient, host preference, behaviour, and physiological state
- Language:
- English
- Description:
- We have studied the effect of different light gradient regimes on host-plant selection of the carrot psyllid, Trioza apicalis Förster. In both a strong and a weak light gradient, carrot psyllids preferred a carrot leaf placed in higher light intensity. When the choice was between the host (carrot Daucus carota L.) and a non-host (barley Hordeum vulgare L.) virgin adults settled significantly more often on non-host in higher light intensity than on carrot in lower light intensity. In a weak light gradient, none of the gravid females settled on a non-host. In an experiment without light gradient, gravid females showed a preference for carrot, whereas virgin females settled approximately equally on Norway spruce Picea abies Karst. (winter shelter plant) and carrot. Our results show that virgin and gravid individuals have different host-plant selection behaviour, and that they are sensitive to small differences in light intensity. Both factors can create a source of variation in behavioural assays, and should be taken into consideration in future experiments with this and probably also related species. Our results suggest that carrot psyllids can utilize visual cues (light intensity or wavelength) in host-plant selection, and the role of visual cues should be more thoroughly studied.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
20. Provisioning patterns and choice of prey in the digger wasp Cerceris arenaria (Hymenoptera: Crabronidae): the role of prey size
- Creator:
- Polidori, Carlo, Boesi, Roberto, Isola, Francesco, and Andrietti, Francesco
- Type:
- article, model:article, and TEXT
- Subject:
- Cerceris arenaria, Hymenoptera, Crabronidae, behaviour, nest provisioning, prey, Curculionidae, and hunting specialization
- Language:
- English
- Description:
- At a nest site in Northern Italy of females of the weevil-hunting digger wasp Cerceris arenaria L. (Hymenoptera: Crabronidae) the provisioning activity and predator-prey relationship were investigated, in particular their specialization in choice of prey. Females were active from middle of June to end of July, and from 8.00 to 19.00. The wasps made provisioning flights throughout the day, mostly in late morning and early afternoon. Individual wasps generally only hunted for 1 or 2 prey species of all those available, maybe because of their higher abundance. The size of prey, which is positively correlated with that of the female wasps, seems to be the main factor determining choice of prey. The nature of the provisioning flights seems to be related to the size of the prey, being more frequent and shorter for smaller weevils. The correlation between prey and wasp biomass is discussed in relation to the size range of the wasps.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
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