bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of host and parasitoid age on search behaviour and oviposition rates in Lariophagus distinguendusFörster (Hymenoptera: Pteromalidae)
Authors: Bellows T. S. 
Published: October 2006

SummaryOviposition rates and related behaviours were quantified for Lariophagus distinguendusFörster attacking Calosobruchus chinensis (L.) and C. maculatus (F.). Oviposition rates varied with parasitoid age; parasitoids aged 1–7 days laid approximately twice as many eggs per day as those aged 8–14 days. Similar differences were noted in search rates and handling times; younger parasitoids had higher attack rates and lower handling times than older parasitoids. Search rates and handling times also varied with the host stage available for attack. Search rates were higher and handling times were lower on larger stages. The results are discussed with reference to their impact on the dynamical behavior of insect parasitoid‐host populations.
A new method to control houseflies, Musca domestica, at waste disposal sites
Authors: Imai Chobei 
Published: October 2006

SummaryInvestigation was carried out from 1976 to 1979 to establish a new control system against the houseflies, Musca domestica, at a sea‐filling waste disposal site in Osaka Bay, Japan.Field surveys showed that the garbage was favorble for the fly breeding for 20–30 days after being disposed, while the sewage sludge and the ash from incinerated refuse were unfavorable. Comparing the fly density at the site to the reported cases of the public complaints in the urban area near to the site, a complaint threshold density of the flies at the site was estimated. Then, a control threshold density was assumed from the complaint threshold density and the reproductive rate of the housefly population. Several insecticides, as well as a surface active agent, polyoxyethylene lauryl ether (PEL), were found effective for the temporary suppression of the fly density.Based on the results obtained, the following control system was worked out. 1) Refuse is disposed onto the same area as other inorganic wastes to deteriorate the capacity of breeding sources. 2) The fly density is examined on newly disposed refuse almost everyday by landfill operators. 3) PEL is sprayed when the density slightly exceeds the control threshold density. If the density increases rather higher, insecticide should be used. 4) The disposed refuse is covered with soil or other inorganic wastes on every weekend or every other weekend by 15 cm thickness.Success in both fly control and reduction of the amounts of insecticides sprayed was achieved by a field application of this new control system.
A new method for describing predator‐prey relations in discontinous environments
Authors: Fujita Kazuyuki 
Published: October 2006

SummaryI propose a new method for anlysing predatorprey interactive systems in discontinuous environments. The basic index used here is a generalized version ofLloyd's (1967) “interspecies mean crowding”, which is defined as the number of individuals of one species existing in a given patch per that of the other species in either the same or different patches at either the same or different times. Four indices are derived from different combinations of the numbers of the prey and the predator in habitat patches. Then, the correlation coefficients between the numbers of individuals in patches in both different locations and times are derived by modifying the above new indices. Using this technique, dynamical changes of the joint distributions of the numbers of predators and prey which reflect variation in local conditions, can readily be described. As an example, this method was applied to an analysis of the outcomes of a multi‐patch version of theLotka‐Volterra model of predator‐prey interactions.
Sampling statistics for Panonychus ulmi (Koch) (Acarina, Tetranychidae) and Tetranychus urticae Koch (Acarina, Tetranychidae) feeding on apple trees
Authors: Zahner Ph. , Baumgaertner J. 
Published: October 2006

SummaryThe distribution of Panonychus ulmi (Koch) and Tetranychus urticaeKoch as observed in Swiss apple orchards was analyzed in a multi‐stage sampling procedure. Based on the variance‐mean relationship (Taylor, 1961) a transformation of mite counts was made. Major sources of variation were found in between‐tree and between‐crown level differences. In usingBliss andOwen's (1958) method the negative binomial model was concluded to be appropriate for the description of the P. ulmi but not for the T. urticae distribution. HenceCroft's et al. (1976) sampling statistics was recalculated for P. ulmi only. The mean crowding index (Lloyd, 1967) was linearly related (Iwao, 1968) to the mean for P. ulmi and to a less extent for T. urticae that was found in much lower density range. Based on the mean crowding statistics a sampling program afterKuno, (1976) is proposed for both species. Some differences between the sampling plans and their applicability are discussed.
Resource allocation and time budgeting in adults of the cockroach, Periplaneta americana: The interaction of behaviour and metabolic reserves
Authors: Rollo C. David 
Published: October 2006

SummaryActivity (to food, water and shelter) and resource allocation (mass budget, and size of various body components) were examined in populations of adult Periplaneta americana subjected to periods of starvation or sugar feeding. Following 13 days of starvation, roaches ate 5 times their normal daily ration and feeding required about 20 days to return to pre‐starvation levels. When sucrose was substituted for the usual dog‐food diet for 13 days, there was also a large increase in feeding initially. When the dog food was re‐established, however, there was very little feeding for about one week. Although reproduction was markedly curtailed by starvation, females fed sucrose continued reproducing for at least 59 days. The results suggested that the roaches were mainly energy limited.Although the consumption of roaches was strongly affected by reserve depletion, eating was a small component of the time budget, and overall activity was relatively unchanged by starvation or sugar‐feeding. There was a slight decrease in activity during starvation, but the circadian pattern remained unchanged. Females carrying oöthecae were highly active and were apparently attracted to food (even though they ate little). Thus the activity of the population was dominated by circadian rhythmicity and the reproductive cycle.
Why do Luehdorfia butterflies lay eggs in clusters?
Authors: Itô Yosiaki , Tsubaki Yoshitaka , Osada Masaru 
Published: October 2006

SummaryLuehdorfia butterflies lay eggs in clusters. Clones of their host plants (Asiasarum and Heterotropa) are distributed pacthily among the understory of deciduous forests. Groups of Luehdorfia larvae often exhaust the clones and may wander over the forest floor seeking new clones. The highest mortality observed is during this wandering period. To elucidate why Luehdorfia butterflies lay eggs in clusters, a simulation experiment was made for hypothetical populations which lay eggs in clusters or singly. Field data on larval mortality, consumption, density of host clones and leaf weight for Luehdorfia japonica were incorporated into the model. The predictions of the simulation were: (1) When the egg density is low, the single egg type could leave many more pupae than the egg clustering type, but when the egg density is high, the former might leave smaller number of pupae than the latter; and (2) There are optimal sizes of egg clusters for different egg densities and the optimal size becomes larger as the egg density increased.
Ecology of the fiddler crab Uca (Thalassuca) vocans vocans (Linnaeus) (Decapoda: Ocypodidae) I. Daily activity in warm and cold seasons
Authors: Nakasone Yukio 
Published: October 2006

SummaryField observations on the behaviour of Uca (Thalassuca) vocans vocans were made in the estuary of the Okukubi river, Okinawa Island.The formation of the feeding aggregation of wandering individuals or drove was found in warm seasons above an average monthly air temperature 20°C from April to early November, while the aggregation was little observed in cold seasons below the temperature from the middle of November to March.The members of the aggregation tended to move down from the upper levels of burrow area, rather than lower levels. This may be related to the richness of organic matters in the substratum of the lower levels as compared with the upper levels. The feeding aggregation was mostly composed of males, but in June females were numerously seen and its peak occurred in June. It suggested that the peak in June is related to both feeding and copulation.Behaviour different from warm seasons was observed in cold seasons. When feeding on surface soil or Enteromorpha the crabs carried a mass of surface soil or the alga into their burrow. It was though that this behaviour was related to the storage of food.It seems likely that the crabs maintain the population by the formation of the aggregation of wandering feeders in warm seasons when there are no algae and by feeding abundant algae as well as surface soil or by storing up food in good weather for bad one in cold seasons.
Foraging strategy of a non‐omniscient predator in a changing environment (II) model with two data windows and a relative comparison criterion
Authors: Inoue Tamiji 
Published: October 2006

Summary
The model with two data windows and the relative comparison criterion (SRC) is proposed based on a Dynamic Programming problem. The model deals with predators whith remember separately the profitability of each patch and visit patches repeatedly. The model predator can remember foraging results that have occurred within the duration of memory (Dm). But when the number of foraging results in one patch exceeds the capacity of the memory chamber (Cm), older results are deleted from memory. Cm is the short data window for patches searched recently and Dm is the long one for patches searched in the past, but not recently. The model predator always searches at the patch with the highest estimation of profitability.
The validity of SRC was checked by the experiment with great tits ofSmith andSweatman (1974). SRC could describe satisfactorily weil the experimental result that great tits at first searched almost uniformly and then concentrated their foraging efforts to good patches but they could not detect the new good patch after changes in food distribution. These analyses showed that great tits did not forage in an optimal manner in the experimental conditions ofSmith andSweatman (1974).
Differences of SRC from the exploration and exploitation model ofKrebs et al. (1978) and from the model with one data window and the absolute criterion (SAC) of Inoue (1983) were discussed to show characteristics of the two extreme strategies for sampling the patchy environment.
Estimation of prey consumption of a mantid, Paratenodera angustipennis (S.) in a natural habitat
Authors: Matsura Toshiaki , Nagai Shinichi 
Published: October 2006

SummaryUsing a relationship between prey consumption and growth rate, field prey consumption of adults of Paratenodera angustipennis (S.) in a paddy field was estimated. Since a great number of grasshoppers (Oxya japonica) lived in the research area and the mantids had frequently eaten O. japonica, we presumed that they consumed only O. japonica. As a result, it was estimated that average prey consumptions for 6 days were 406 mg for the females and 23 mg for the males. From the result of this estimation and the feeding rhythm of the mantids, it is concluded that each female captured one grasshopper on average every a few days.By comparing this actual feeding level of P. angustipennis with those of other predacious arthropods, characteristics of P. angustipennis as a predator were discussed.
Variation due to maternal age in the onion root maggot, Hylemya antiqua (Meigen)
Authors: Goth G. J. , Wellington W. G. , Contant H. Y. 
Published: October 2006

SummaryA variety of characteristics were studied in populations of the onion root maggot, Hylemya antiqua, to determine the extent to which the age of the female producing a batch of eggs might affect heterogeneity in her offspring.Early‐born offspring were found to be reproductively most successful. They had the longest mean expectation of life, a relatively low mortality rate into mid‐life, the highest average fecundity, the highest mean rate of egg production, and they produced the highest percentage of female offspring. On the other hand, mid‐born offspring were hardiest. They also had a long mean expectation of life, comparable to that for early‐born offspring but, in addition, they had the lowest sustained mortality rate and the greatest ability to survive food stress. Their robustness may have been acquired at the expense of certain reproductive capabilities however, in that their average fecundity was lower than their early‐born siblings', and their rate of egg production was more variable. Late‐born offspring were the most mortality‐prone and the least fecund, but they had the shortest mean generation time. These differences must be evaluated in terms of their effects on the rate of natural increase and on population growth.Maternal age was found to influence pupal size, although the provenance groups differed significantly from each other and, in fact, showed opposite trends within their respective cohort groups. Size itself, and the ability of a species to alter the size at which it pupates, may be characteristics which have evolved to fit a specific set of environmental conditions.
The effects of food and density of the movement of Arion ater and Ariolimax columbianus (Pulmonata: Stylommatophora) between habitats
Authors: Hamilton Peter A. , Wellington William G. 
Published: October 2006

SummaryExperiments were conducted to determine if slug density, or food quantity and quality could cause dispersal by slugs. Arion ater dispersed quickly from overcrowded areas, where high mortality was incurred by this species. Poor food conditions, caused more dispersal than good food conditions, but food had no effect on the mortality of A. ater. Neither food nor density factors had significant effects on the dispersal of Ariolimax columbianus. However, more A. columbianus died in the high‐ than low‐density treatments. A. columbianus mortality was unaffected by the food factor. Dispersing Arion were heavier than non‐dispersers, but there was no difference between the weights of dispersing and non‐dispersing Ariolimax. There were significant seasonal changes in the dispersal rate, mortality and weight of dispersing Arion, whereas only the mortality of Ariolimax changed significantly during the experiments.Since Arion ater did not markedly reduce its activity during unsuitable weather it was able to leave areas of poor food and high slug density fairly rapidly. Ariolimax columbianus' large size allowed it to remain inactive during unfavourable weather and permitted this species to be relatively unresponsive to the experimental treatments.
The effects of age and weather on egg laying in Danaus plexippus L. (Lepidoptera: Danaidae)
Authors: Zalucki Myron P. 
Published: October 2006

SummaryThe effects of age and weather conditions on egg laying in D. plexippus were determined for caged females. Age (measured in physiological time), temperature and solar radiation influence egg laying in this species of butterfly. An algorithm taking these factors into account in presented and accounts for 88% of the daily variation in egg laying. Caged D. plexippus begin to lay eggs six—seven days after emergence, peak egg production (about 60 eggs/♀) occurs about 15 days later. Females continue to lay eggs throughout their adult life, which in a flight cage was about 40 days. This egg laying pattern is compared with other published fecundity schedules. The effect and importance of a female being prevented from laying her eggs, on her life‐time egg production, is also discussed.
Optimal clutch size of the chestnut gall‐wasp, Dryocosmus kuriphilus yasumatsu (Hymenoptera: Cynipidae)
Authors: Kato Kazutaka , Hijii Naoki 
Published: October 2006

SummaryOptimal clutch size of the chestnut gall‐wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), was examined in galls on wild and resistant chestnut trees in 1988 and 1989. The rate of escape success of newly‐emerged adults from galls was an average of 60%, irrespective of cell numbers per gall. Dry mass per cell of a gall (as an index of nutritive condition) decreased with increasing cell number per gall, but was proportional to the mean number of mature eggs of new adults per gall. The number of cells per gall that occurred most frequently did not agree with that attained by the maximum survival rate from young larva to adult emergence of the gall‐wasp. This discrepancy was examined from the viewpoint of three factors: 1) quality of offspring, 2) defensive response of the host plant causing mortality of the gall‐wasp before cell formation, and 3) fitness per gall vs. fitness per egg. It is concluded that the third factor is most likely to be the one best in explaining the discrepancy.
Life table analysis of the green rice leafhopper, Nephotettix virescens (distant) (Hemiptera: Cicadellidae), and efficient vector of rice tungro disease in asynchronous rice fields in Indonesia
Authors: Aryawan I Gusti Ngurah , Widiarta I Nyoman , Suzuki Yoshito , Nakasuji Fusao 
Published: October 2006

SummaryPopulation dynamics of Nephotettix virescens was studied in 17 paddy fields transplanted at intervals of about 1 month in 1988–1990. The adult density was highest either in the immigrant or the 1st generation and sharply decreased to the 2nd generation. The survival rate of the 1st generation was lowest in the transition season when areal population density increased. Key factor analysis revealed that the nymphal and adult mortality of the 1st generation (kn) was the principal source of population fluctuations. No significant correaltion was found between kn and natural enemy density, natural enemy density/healthy egg density, or the precipitation during the nymphal period. On these bases adult emigration was suspected to be the key factor. Areal population build‐up of N. virescens in the transition season was considered to occur as a result of increasing immigration to young stages of rice.
Pollination and factors limiting fruit set of chasmogamous flowers of an amphicapric annual, Polygonum thunbergii (Polygonaceae)
Authors: Momose Kuniyasu , Inoue Tamiji 
Published: October 2006

SummaryWe observed phenology and insect visitors of chasmogamous flowers of an amphicarpic annual, Polygonum thunbergii (Polygonaceae) in Kyoto, Japan, and clarified limiting factors for fruit set by bagging and hand‐pollination experiments. Flowering season was one month from late September. Flowers were visited by various insect groups (total 30 families and 64 species) and effective pollinators were lower bees (Halictidae) and wasps (Vespidae) in the early flowering season, and middle‐sized flies (Syrphidae and Calliphoridae) in the later season. Nectar was secreted at a constant rate (0.013mg sugar/hour) throughout a day and >90% of it was consumed by insects. The average number of flowers per ramet was 122, of which 95% were pollinated in the natural conditions. Bagging experiments showed that 47% of flowers were self‐pollinated even under no pollinator visits. Despite of a high probability of cross pollination, the probability of fruit set within the ramet was 0.30 due to resource limitation. We discussed possible adaptive significance of cleistogamous flowers under the condition that seeds could be produced by chasmogamous flowers through self‐pollination even under pollinator limited conditions.
Comparative analysis of population characteristics of the brown planthopper, Nilaparvata lugens stål, between wet and dry rice cropping seasons in West Java, Indonesia
Authors: Sawada Hiroichi , Kusmayadi Ayi , Gaib Subroto S. W. , Suwardiwijaya Edi , Mustaghfirin  
Published: October 2006

SummaryPopulation dynamics of the brown planthopper (BPH),Nilaparvata lugens Stål, were investigated in paddy fields in the coastal lowland of West Java, Indonesia, where rice is cultivated twice a year, in the wet and dry cropping seasons. Distinct differences in the basic features of population dynamics were detected between the two rice cropping seasons: (1) In the wet season, BPH populations multiplied rapidly in the period from initial to peak generation, reaching quite often the destructive level despite the low density of initial immigrants. However, in the dry season, the population growth rate and the peak population density were much lower than those in the wet season. The abundance of natural enemies such as arthropod predators played a major role in determining such a difference in seasonal population development. (2) The density at the peak generation or the occurrence of outbreaks in each field was predictable in the wet season with fairly high accuracy on the basis of the density at the initial or previous seasonal generations. In the dry season, however, the rate of population growth and the peak population density widely varied among the fields depending on the water status in each field. (3) Density‐dependent processes to regulate the population density were detected in both cropping seasons. In the wet season, the regulatory processes were only detected in such high densities as cause the considerable deterioration of host plants, which suggested that the processes were largely attributable to intra‐specific competition. In the dry season, however, the regulatory processes operated at a much lower density in the earlier stages of the crops. The results of an analysis of adult longevity or residence period suggested that the density‐dependent dispersal of macropterous adults played an important role in stabilizing the population fluctuation among the fields in the early dry season.
Structural MRI discriminates individuals with Mild Cognitive Impairment from age‐matched controls: A combined neuropsychological and voxel based morphometry study
Authors: Trivedi Mehul A. , Wichmann Allison K. , Torgerson Britta M. , Ward Michael A. , Schmitz Taylor W. , Ries Michele L. , Koscik Rebecca L. , Asthana Sanjay , Johnson Sterling C. 
Published: October 2006

BackgroundSeveral previous studies have reported that amnestic mild cognitive impairment (aMCI), a significant risk factor for Alzheimer's disease (AD), is associated with greater atrophy in the medial temporal lobe (MTL) and posterior cingulate gyrus (PCG).MethodIn the present study, we examined the cross‐sectional accuracy (i.e., the sensitivity and specificity) of voxel‐based morphometry (VBM) in discriminating individuals with MCI (n = 15) from healthy age‐matched controls (n = 15). In addition, we also sought to determine whether baseline GM volume predicted aMCI patients that converted to AD from those that did not approximately 2 years after the baseline visit.ResultsMCI patients were found to display significantly less GM volume in several hypothesized regions including the MTL and PCG relative to the age‐matched controls (p < 0.01). Logistic regression analysis and receiver operating characteristic (ROC) curves for GM volume in the anterior MTL and PCG revealed high discriminative accuracy of 87%. By contrast, baseline GM volume in anterior MTL and PCG did not appear to be sensitive to changes in clinical status at the follow‐up visit.ConclusionThese results suggest that VBM might be useful at characterizing GM volume reductions associated with the diagnosis of aMCI.