bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nest thermoregulation in Vespa simillima, V.tropica and V.analis
Authors: MARTIN STEPHEN J. 
Published: March 2008

Abstract. 1. Nest thermoregulation follows a similar pattern in Vespa simillima Smith and V. tropica L. There is a gradual decline in the daily fluctuations of nest temperature to a constant steady state which is maintained during the production of the first sexuals, followed by a sudden loss of stability at the end of the colony cycle.2. The larvae are not major producers of heat, as they are unable to raise their body temperature by more than 1–2°C above ambient. However, they act as heat reservoirs and providers of food in the form of larval secretions. This feeding may allow workers to raise their body temperature during non‐foraging periods.3. The adults are capable of raising their body temperature many degrees above ambient and the presence of even one adult, in this case a V.analis F. mother queen, was able to raise the nest temperature.4. Supplementary carbohydrate food promotes thermogenesis and enhances colony development.
Host refuges and spatial patterns of parasitism in an endophytic host–parasitoid system
Authors: ROMSTÖCK‐VÖLKL MARIA 
Published: March 2008

Abstract. 1. Larvae of Tephritis conura Loew (Diptera: Tephritidae) live gregariously in flower heads of Cirsium heterophyllum (L.) Hill (Cardueae). They are attacked by the endoparasitic wasps Eurytoma sp. near tibialis Boheman (Hymenoptera: Eurytomidae) and Pteromalus caudiger (Graham) (Hymenoptera: Pteromalidae).2. The responses of the parasitoids to different host patch sizes were investigated from the analysis of field samples. At the host population level, overall probabilities of parasitism were independent of host numbers per flower head or showed a tendency to inverse density‐dependence for both parasitoid species.3. Measurements of ovipositor length in Eurytoma and P.caudiger indicated that parts of the flower head constitute a structural refuge from parasitism.4. The accessibility of hosts in a flower head was found to differ markedly, depending on larval locations and flower head characters. In spite of this high variability, similar average percentages of larvae were accessible to the parasitoids in each patch size class.5. High variability of oviposition success in laboratory experiments can be explained by random locations of hosts in the flower heads.
Interference competition among burying beetles (Silphidae, Nicrophorus)
Authors: TRUMBO STEPHEN T. 
Published: March 2008

Abstract. 1. This study investigated the impact of intraspecific and interspecific competition on the reproductive success of a biparental burying beetle, Nicrophorus defodiens Mannerheim.2. Marked pairs or single females were placed on small and large mouse carcasses in the field in 1985 and 1986. Carcasses were exhumed after 9–10 days to determine the identity of the resident adult(s) and the production of young.3. Competition was assessed by the prevalence of takeovers by intruders (unmarked adults). For N.defodiens, after the initial colonization of the carcass, interspecific competition from larger N.orbicollis Say and N.sayi Laporte was substantial and more intense than intraspecific competition. Competition was also greater in the middle of the breeding season and on large as opposed to small carcasses.4. Successful takeovers resulted in the expulsion of the prior resident(s), killing of any offspring present on the carcass, and oviposition of a new clutch by the intruder.5. Females aided by males were more likely than single females to avoid takeovers but did not produce larger broods or larvae of larger mass.6. An additional laboratory experiment in 1985 and a field experiment in 1986 suggest that N.defodiens is able to reproduce on very small carcasses despite intense heterospecific activity.
Absence of intraspecific interference during feeding by the predatory ladybirds Chilocorus spp. (Coleoptera: Coccinellidae)
Authors: HATTINGH VAUGHAN , SAMWAYS MICHAEL J. 
Published: March 2008

Abstract. 1. The hypothesis was tested that intraspecific behavioural interference does not adversely affect the feeding behaviour of adults of three predatory coccinellid species, Chilocorus nigritus (F.), C.bipustulatus (L.) and C.infernalis Mulsant, at densities found under field conditions.2. Feeding rates on mature oleander scale Aspidiotus nerii Bouché were evaluated by two methods at various predator densities. Proportion of the population dispersing was also measured for one of the species.3. Feeding rate did not decrease and dispersal did not increase with increasing predator density. No significant behavioural interference that might have reduced predatory efficiency was observed, counter to assumptions on which published interference models are based.4. Results here help to explain the relative importance of parasitoids and predators in the effective control of red scale Aonidiella aurantii (Mask.). The results also provide guidelines for release of these bio‐control agents.
Significance of spring migration and flexibility in flight‐muscle histolysis in waterstriders (Heteroptera, Gerridae)
Authors: KAITALA ARJA , HULDÉN LARRY 
Published: March 2008

Abstract. 1. Individuals of long‐winged waterstrider (Gerridae) species were found in spring far from their breeding habitats, which indicates that they fly before reproduction.2. Field samples and laboratory studies show that once they return to their breeding sites, many individuals of three waterstrider species (Gerris odontogaster (Zett.), Gerris lacustris (L.) and Limnoporus rufoscutellatus (Lat.)) histolyse wing muscles and lose flight ability during their reproductive period.3. The extent of flight‐muscle histolysis varies with environmental factors. Food scarcity affects flight‐muscle histolysis in G.odontogaster females. In G.Lacustris, flight‐muscle histolysis was more common in the laboratory than in the field samples. Proportionately more females than males lost their flight ability by the end of the reproductive period.4. Flight ability had direct costs in reproductive potential with (non‐flyer) females, which histolysed their flight muscles, laying more eggs than (flyer) females, which maintained flight ability. This was also the case during food scarcity. Non‐flyer males of G.odontogaster survived longer than flyer males.5. Spring migration was distinguished from dispersal during the reproductive period, because these flights serve different functions. Flight‐muscle histolysis of females during reproduction is a qualitative reproductive option, with a trade‐off between dispersal ability and reproductive potential. Ability to change reproductive behaviour depending on environmental conditions increases an individual's ability to cope with a large variety of habitats.
The effects of survival and weather on lifetime egg production in a model damselfly
Authors: THOMPSON DAVID J. 
Published: March 2008

Abstract. 1. A simulation model is presented which describes, from field‐estimated parameters, the effects of daily survival rate and proportion of sunny days on the lifetime egg production of females of the damselfly Coenagrion puella (L).2. Lifetime egg production increases with daily survival rate and proportion of sunny days.3. Estimates of mean lifetime egg production per female in bad and good summers in northern England ranged from 333 to 740.4. The distribution, as well as the proportion, of sunny days influences lifetime egg production. For a given combination of daily survival and proportion of sunny days, lifetime egg production decreases as the distribution of sunny days becomes more clumped.5. Lifetime egg production is largely determined by chance; females who begin their mature adult life during a period of sunny weather can produce many times more eggs than those whose mature adult life coincides with cloudy days.
Differential resource utilization and co‐occurrence of leaf miners on oak (Quercus dentata)
Authors: SATO HIROAKI 
Published: March 2008

Abstract.

Spatial, temporal, and dietary differences in resource utilization and patterns of interspecific association on leaves were investigated for dominant and common leaf‐mining species on an oak species, Quercus dentata Thunb., in Hokkaido, northern Japan.
Leaf miners were divided into two groups according to leaf tissues used for food: upper‐layer‐feeders which consume the palisade paren‐chymatous layer (Stigrnella spp. and tenthredinid sp.), and full‐depth‐feeders which consume spongy and palisade parenchymatous layers (Phyllonorycter leucocorona (Kumata), P.similis Kumata, and Caloptilia sapporella (Matsumura)).
Differences in the position of mines on leaves were found among species: mines of P.similis were distributed more frequently in the middle section of leaves, whereas those of the remaining species were concentrated in the basal section.
Leaf size preference differed between species: C.sapporella and tenthredinid sp. tended to select larger leaves more frequently than did the other species.
Phenological differentiation was found among species: C.sapporella appeared earliest, followed by P.similis, P.leucocorona and a tenthredinid sp., and then Stigmella spp.
Each species showed a highly clumped distribution among leaves. Leaf miners of some species pairs co‐occurred on leaves more frequently than expected by chance.
Fitness and habitat segregation of British tree‐hole mosquitoes
Authors: BRADSHAW W. E. , HOLZAPFEL C. M. 
Published: March 2008

Abstract.

Populations of three mosquitoes, Aedes geniculutus (Olivier), Anopheles plumbeus Stephens and Culex torrentium Martini, were found in three types of tree holes: rot holes penetrating the bark of the host tree and exposed, or deeper, more cryptic, bark‐lined buttress holes. Aedes geniculatus occupied all three tree‐hole types but reached their greatest abundance in exposed buttress holes; A.plumbeus predominated in rot holes; C.torrentium occupied buttress holes exclusively.
After a 1 month period of winter freezing, larvae of A.plumbeus survived better than larvae of A. genicularus. Freeze resistance of A.plumbeus increased from cryptic buttress to rot holes. Freeze resistance of A.geniculatus declined from exposed buttress to cryptic buttress to rot holes and was markedly higher in more protected than in more exposed macrohabitats.
Among manipulated larval cohorts of A.geniculutus and A.plumbeus, survivorship, pupation success, pupal weight, and/or biomass yield did not differ among tree‐hole types or was the reverse of freeze‐related survivorship. Despite seasonal differences in fitness correlates, annual fitness may be similar among tree‐hole types for both species. Manipulations carried out at a single census or during a single season are therefore likely to produce misleading information about fitness variation among sub‐habitats.
Both species should exploit a broad range of tree‐hole types but A.plumbeus occupies more restricted types of tree holes than does A.geniculutus. The restricted habitat usage by A.plumbeus does not parallel their fitness among tree‐hole types in southern Britain but does resemble that of other tree‐hole anophelenes. We therefore propose that habitat selection by A.plumbeus is more likely due to their phylogenetically determined physiological tolerances and behaviour than to competition from coexisting A.geniculatus.
Multiple mating and its effect on the reproductive success of female Epiphyas postvittana (Lepidoptera: Tortricidae)
Authors: DANTHANARAYANA W. , GU H. 
Published: March 2008

Abstract.

Multiple mating and its effect on reproductive performance of female Epiphyas postvittana (Walker) moths were studied under controlled conditions.
The age at which the moths mated for the first time ranged from the first to the tenth day after emergence, but 71% of first matings were during the first 3 days.
The majority (63%) of females had one or two spermatophores in the bursa copulatrix. Some (24%) were found with three to five spermatophores, whereas no successful mating occurred among 13% of individuals. The number of matings was partly dependent on the number of mates available to the female. Between the range of sex ratios of one male to one female and four males to one female maximal mating success occurred at the ratio of three males to one female.
Virgin females were capable of egg‐laying, but mating stimulated and accelerated oviposition. Mated individuals laid twice as many eggs as unmated ones.
The level of copulatory activity did not influence the longevity of females irrespective of the number of males available to them.
Sex ratios with greater than one male to a female improved the reproductive success by marginally increasing fecundity and fertility.
It is concluded that multiple mating would enhance population growth, and is of particular benefit to populations with a preponderance of females, as is known to occur naturally in this species.
Is foraging in the desert ant, Messor pergandei (Hymenoptera: Formiceidae), limited by water?
Authors: FEENER DONALD H. , LIGHTON JOHN R. B. 
Published: March 2008

Abstract.

The seed‐harvesting ant Messor (Veromessor) prrgandei (Mayr) is a common inhabitant of southwestern deserts of the U.S.A. Foragers vary in size from less than 1 mg to more than 10 mg in body mass and may travel over 80 m on a single foraging trip. Their small size, long foraging range, and hot, arid habitat suggest that water stress may limit foraging activity. We examined intercolony and interindividual variation in water loss of M.pergandei foragers under several different situations in the field.
Colonies differed significantly in minimum critical water content (Wc) of individual foragers (water content below which foragers are incapable of normal locomotion). In one colony small workers had disproportionately higher Wc than larger workers; in the other colony Wc was isometric with body size.
Groups of workers confined in the field approached Wc only after normal foraging stopped and substrate temperatures exceeded 45°C, while water content of individual foragers did not approach the Wc during normal foraging periods. Moreover, seed load and distance travelled did not negatively affect forager water content, as measured on return to the nest: indeed, our results suggest that forager hydration level may influence load selection and/or foraging distance. We conclude that, under normal circumstances, foraging in M.pergandei is not water‐limited.
The effect of sublethal neogregarine infections in the spruce needleminer, Epinotia tedella (Lepidoptera: Tortricidae)
Authors: MÜNSTER‐SWENDSEN M. 
Published: March 2008

Abstract.

A hitherto unknown factor causing cyclic reduction in population fertility of Epirzotia tedella (Cl.) was identified as sublethal infections of the neogregarine Mattesia sp.
Infection probably takes place when larvae enter hibernation, but does not develop into spore production until the formation of pupae and adult moths.
At the individual level, the sublethal neogregarine infection causes a slight delay in adult emergence, a decreased adult lifespan, a suppression of egg development, and thus a reduction in fertility.
At the population level, fertility reduction has a delayed density dependent component and, through correlation, Mattesia is assumed to be causative. Since fertility reduction is a key‐factor in E.tedella, Mattesia may even be a dominant factor in the dynamics of this species.
Mattesia infections were found in no other dominant insect species at the locations, and consequently the interaction between E.tedella and Mattesia sp. seems to be specific. Such delayed density dependent interaction can create host oscillations, as seen in many forest insects. However, host‐parasitoid interaction alone leads to oscillations with the observed period of 6–8 years length, and the neogregarine infections apparently act in parallel with the parasitoids and enhance the amplitude of the oscillations.
Butterfly migration from and to peninsular Florida
Authors: WALKER THOMAS J. 
Published: March 2008

Abstract.

Migrating butterflies were monitored with traps for 10 years at a site in north peninsular Florida, to determine seasonal and annual variation in numbers and directions of flight.
In the spring, 81–96% of the principal migrants, Phoebis sennae (L.), Agraulis vanillae (L.), Precis coenia (Hübner) and Urbanus proteits (L.), flew northward; in the autumn, 86–95% flew southward.
Estimated mean net numbers of these four species flying northward in spring across each ENE‐WSW metre were 3, 6, 69 and <1 respectively; numbers flying southward in autumn were 222, 413, 37 and 146.
During a 5‐year period, the ratio of highest to lowest seasonal migration for a species did not exceed 9.3.
The average median date of spring migration was 27 March for P.sennae, 23 April for P.coenia, and 12 May for A.vanillae. The average median date of autumn migration was 2–5 October except for U.proteus, whose average date was 14 October.
The autumn migratory period, as measured by the duration of the middle half of migration, was about 2 weeks in P.coenia and about 4 weeks in the other three species.
Compared to previously reported butterfly migrations, the ones studied here were notably uniform in magnitude and regular in timing.
These and other data suggest that 4 million or more of these butterflies migrate northward from peninsular Florida almost every spring and that 40 million or more migrate southward to peninsular Florida almost every autumn.
Comparative nutritional ecology of bryophyte and angiosperm feeders in a sub‐Antarctic weevil species complex (Coleoptera: Curculionidae)
Authors: CRAFFORD J. E. , CHOWN S. L. 
Published: March 2008

Abstract.Highly productive and st,ructurally diverse angiosperm communities occur on sub‐Antarctic Marion Island, yet cryptogams are the main source of energy and nutrients for five of the six native weevil species (Curculionidae: Ectemnorhinini) that occur there.Previously it has been hypothesized that low‐temperature regimes, during the Pleistocene, precluded angiosperm herbivory. This hypothesis was based,inter alia, on the assumption that at low temperatures feeding on bryophytes is more nutritionally advantageous than feeding on vascular plants.This assumption was tested by comparing the consumption rate (CR) and approximate digestibility (AD) (mass and energy) of bryophytes and angiosperms in twoDusmoecetesspecies indigenous to Marion Island.The approximate digestibility ofBlepharidophyllum densifolium(Scapaniaceae) energy and dry mass were similar forD.marioniJeannel adults at 5°C and at 10°C.D.similis(C. O. Waterhouse) adults fedAzorella selagoHook (Apiaceae) leaves also had similar AD for food dry mass and energy at 5°C and at 10°C. However, the performance ofD.similisonA.selagoleaves and flowers at 5°C was better than that ofD.marionion bryophytes at both temperatures.Bryophyte feeding does not appear to be nutritionally more advantageous at low temperatures in the sub‐Antarctic, nor does angiosperm herbivory appear to be comparatively disadvantageous at low temperatures, althoughD.similisdoes not feed onAcaena magellanica(Lam.) (Rosaceae) at 5°C. It seems likely that moss‐feeding evolved in response to an absence of angiosperms during glacial periods, rather than because of a nutritional advantage associated with bryophagy at low temperatures.
Colony ergonomics for a desert‐dwelling bumblebee species (Hymenoptera: Apidae)
Authors: SHELLY TODD E. , BUCHMANN STEPHEN L. , VILLALOBOS ETHEL M. , O'ROURKE MARY K. 
Published: March 2008

Abstract.

Data on worker traffic, size and concentration of nectar loads, and size and composition of pollen loads were collected for a colony of Bombus pennsylvanicus sonorus Say in the Chihuahuan Desert in Arizona, U.S.A.
Foraging activity increased through the morning to a peak level in early afternoon and then declined steadily thereafter. Pollen collection occurred primarily in the morning, whereas nectar was harvested throughout the day. Nectar loads decreased in size but increased in sugar concentration during the day.
Following field observations, we excavated the nest and counted the numbers of immatures and adults present and measured the honey and pollen reserves. A total of 150 workers were present, and we estimate that the colony would have produced 174 queens and 192 males. Food reserves appeared small: pollen and honey stored in the nest represented only 18% and 35%, respectively, of the daily input.
These results are compared to ergonomic data collected for B.vosnesenskii in the only other similar study.
Host selection and sex ratio in a heteronomous hyperparasitoid
Authors: WILLIAMS TREVOR 
Published: March 2008

Abstract.

Encarsia tricolor Förster is a heteronomous hyperparasitoid: females develop as primary endoparasitoids of Homoptera, whereas males develop hyperparasitically in primary endoparasitoids, including conspecific females.
When offered pupae of Encarsia inaron (Walker) or conspecific pupae, E.tricolor showed a distinct preference to exploit E.inaron for male production.
Parasitoids were given the opportunity to gain different types of ovipositional experience on male and female hosts and were then offered patches containing mixtures of male and female hosts in various ratios. The mean sex ratio which they laid was not dependent on the relative availability of each type of host, whereas prior ovipositional experience had a significant effect.
Adaptive reasons for the observed oviposition strategies are suggested.
Species number, species abundance and body length of arboreal arthropods associated with an Australian rainforest tree
Authors: BASSET YVES , KITCHING R. L. 
Published: March 2008

Abstract.

The species number, the abundance per species and the body length of arthropods foraging within the crowns of an over‐storey rainforest tree from Australia, Argyrodendron actinophyllum (Sterculiaceae), were investigated by interception trap sampling and restricted canopy fogging. Emphasis was placed upon the interpretation of trap data. Arthropods were trapped continuously day and night, over a 2‐year period and the final analyses examined the attributes of 759 species which represented 20,500 individuals.
The proportion of‘rare’species (Le. collected once) intercepted was high (35.7%), although lower than in other similar rainforest surveys. Neither the α log‐series nor the log‐normal distribution could be fitted to the relationship between number of species and number of individuals, since the number of rare species was much higher than predicted and the mode of the distribution could not be identified. The proportion of rare species was higher in fogging collections (452%) than in trap collections.
The data are compared with a study of Bornean arboreal beetles, obtained by fogging trees during a single sampling event. Several patterns were common to both data sets. However, the three‐dimensional plot of the variables describing the structure of the arthropod community showed a notably rougher surface than in the case of Bornean beetles.
Although several factors may complicate the interpretation of the three‐dimensional plots, long‐term and continuous sampling may alter our perception of complex arthropod communities. This methodology is imperative for a proper understanding of arthropod community structure in rain forests.