bluuebunny/crossref_metadata_2025_split huggingface dataset:
The variation in population densities of fleas in house martin nests in Leicestershire
Authors: CLARK FRANK , McNEIL D. A. C. 
Published: March 2008

Abstract. 1. Five species of flea were recorded from 150 nests taken from house eaves in Leicestershire. Three species, C.hirundinis, C.farreniand C.rusticus, were associated with nests used for breeding by martins in the year of collection whilst C.gallinae and C.fringillae were associated with nests used by sparrows.2. Analysis of the three species of martin fleas with various characteristics of the structure and location of the nest revealed that all three species favoured the presence of nest lining consisting of feathers or grass (or the two combined) in preference to straw or to no nest lining.3. Both C.hirundinis and C.rusticus showed a preference for the texture of the surface to which the nest was attached, the former preferring nests attached to plain brick, or pebble‐dashed surfaces, whilst the latter preferred pebble‐dash to stone. Both also showed a relation with the height of the nest above ground level.4. The numbers of C.hirundinus showed a strong positive correlation with those of C.farreni and C.rusticus, which were not correlated with each other.5. Lastly, the number of nests collected that had been used by house sparrows and contained C.gallinae and C.fringillae was too small to allow us to reach any conclusion about their preferences.
A modification of the Lincoln Index for estimating the population densities of mobile insects
Authors: FLETCHER B. S. , KAPATOS E. , SOUTHWOOD T. R. E. 
Published: March 2008

Abstract. 1. To estimate populations of D.oleae in olive groves on Corfu by mark—recapture techniques, McPhail traps had to be used for sampling.2. The prolonged sampling period (24 h) resulted in a differential loss of marked flies from the area and this biased the population estimates obtained from the standard Lincoln Index.3. A modification was devised which enabled the rate of loss of marked flies to be calculated and incorporated into the Index as a correction factor.4. Field comparisons indicated that the modified Index gave more accurate population estimates than the standard Lincoln Index and therefore it may be applicable to other situations when ‘instantaneous’ sampling of populations is not practicable.
The function of turret building behaviour in the larval tiger beetle, Cicindela willistoni (Coleoptera: Cicindelidae)
Authors: KNISLEY C. BARRY , PEARSON DAVID L. 
Published: March 2008

Abstract. 1. Cicindela willistoni LeConte (Coleoptera: Cicindelidae) adults and larvae occur only on saline and alkali flats with little or no vegetation in southwestern U.S.A. Unlike other larval tiger beetle species, C.willistoni constructs a chimney‐like extension (turret) 1–4 cm above its burrow.2. The function of these unique turrets was tested in relation to several biotic and abiotic factors in the Sulphur Springs Valley, Arizona, U.S.A.3. The turrets did not prevent flooding of the larval burrows.4. They did not prevent or reduce the frequency of parasitoids (mainly bombyliid flies of the genus Anthrax).5. The turrets did not make it possible for the adult and larval beetles to feed on obviously different types or sizes of prey.6. However, larvae with turrets were raised sufficiently above the substrate surface and boundary layer to allow them to thermoregulate in the lower temperatures at these heights and remain active throughout the day.7. The shade produced by the turrets attracted significantly more potential prey items than were available to turretless larvae in the same habitat.
Host tree influences on the dispersal of first instar gypsy moths, Lymantria dispar (L.)
Authors: LANCE DAVID , BARBOSA P. 
Published: March 2008

Abstract. 1. In laboratory tests, first instar gypsy moths attempted dispersal more frequency when exposed to less acceptable foliage.2. First instars from small eggs attempted dispersal less frequently than larvae from large eggs when exposed to foliage from highly acceptable or marginally acceptable hosts. Dispersal rates of larvae from medium sized eggs were intermediate.3. These results (1–2) confirm and expand upon the findings of Capinera & Barbosa (1976).4. In the field, data on the relative densities of larvae on different host species support the conclusion that the frequency of dispersal attempts is inversely related to host acceptability.5. The implications of these findings for the population dynamics of the gypsy moth are discussed.
The inheritance and maintenance of the melanic form nigrescens of Pachycnemia hippocastanaria (Lepidoptera: Ennominae)
Authors: MAJERUS M. E. N. 
Published: March 2008

Abstract. 1. A New Forest population of P.hippocastanaria with both typical and nigrescens forms was studied over 6 years. The nigrescens form constituted between 10% and 17% of the population.2. Breeding experiments showed that the nigrescens form is inherited as a unifactorial recessive; however, rearing at low temperatures induces a phenotype similar to nigrescens to result from insects with a genotype which normally produces typical imagines.3. Old collections of P.hippocastanaria suggest that the frequency of the nigrescens form in the New Forest area has increased over the last 100 years.4. Samples collected from other areas, within and outside the New Forest, indicated that the distribution of nigrescens is limited to heaths within the New Forest and on the extreme eastern border of Dorset.5. A number of speculative reasons for the increase in the frequency of the nigrescens form in this area are suggested.
Butterfly migration: are synoptic‐scale wind systems important?
Authors: WALKER THOMAS J. , RIORDAN ALLEN J. 
Published: March 2008

Abstract. 1. If synoptic‐scale wind systems are important in determining long‐distance movements of butterflies, a portion of the variation in daily counts of migrants at a site should be explainable by prior winds.2. Using special flight traps near Gainesville, Florida, U.S.A., from 29 August until 12 November 1978, we made replicated, continuous counts of four migrant species: Phoebis sennae, Urbanus proteus, Agraulis vanillae and Precis coenia.3. Significant SSE‐ward flights occurred for one or more of the four species on 47 days between 5 September and 6 November (Fig. 1).4. Seasonal changes in numbers of migrants were similar for the four species (Fig. 1). Median fall migrants were trapped between 22 September (A.vanillae) and 1 October (U.proteus and P.sennae).5. Daily fluctuations in total numbers of migrants were largely attributable to local weather, viz temperature, wind speed and cloud cover (Fig. 2).6. Neither local wind direction (Fig. 3) nor back‐tracking the positions of air parcels (Fig. 4) helped explain the daily fluctuations.7. The characteristic autumn weather patterns of south‐eastern U.S.A. and the day‐to‐day steadiness of the numbers of migrants are incompatible with the hypothesis that synoptic‐scale wind systems are important in determining butterfly migrations through Gainesville, Florida, in the autumn.
The role of cereal growth stages and crowding in the induction of alatae in Sitobion avenae and its consequences for population growth
Authors: WATT A. D. , DIXON A. F. G. 
Published: March 2008

Abstract. 1. Alatiform nymphs of Sitobion avenae were first recorded on wheat in 1977 and 1978 when there were 0.6 aphids per tiller and reached a maximum proportion of 0.9 of the population despite a seventeen‐fold difference in aphid density between years.2. At the same aphid density per tiller there was a higher proportion of alatiform nymphs on the tillers at an advanced than at an earlier stage of plant growth.3. Both pre‐ and post‐natal crowding, and late stages of plant growth, were important in inducing the development of alatae in the laboratory.4. Changes in the quality of the host plant through its previously reported effect on reproductive and survival rates, and its effect on alate induction and emigration was important in shaping the population dynamics of S.avenae on cereals.
Nest construction and larval behaviour of Bubas bison (L.) and Bubas bubalus (01.) (Coleoptera, Scarabaeidae)
Authors: KLEMPERER H. G. 
Published: March 2008

Abstract.

Female beetles working alone or in cooperation with a male excavated vertical, tunnel‐shaped brood chambers. Each chamber was filled with dung to form a cylindrical brood mass which contained two eggs, one near each pole.
To examine the possible relationship with other Onitini (which lay either one or several eggs per brood mass) factors that influence the two‐egg programme were studied. Brood masses with only a single egg were formed if excavation was resumed prematurely. Conversely, when excavation was suppressed several oviposition programmes fused to produce a multi‐egg brood mass.
The larvae repaired their chambers in the typical Scarabaeine manner by building a self‐supporting wall formed from their own excrement. This behaviour also prevented direct contact and fighting between adjacent larvae in the same brood mass, and it allowed the larvae to survive inside artificial brood balls. Similar behaviour was observed in larvae of Onthophagus taunts and Ontho‐phagus vacca (which develop in one‐egg brood masses). The evolution of nesting habits that involve multi‐egg brood masses or free‐standing brood balls may depend on the pre‐existence of this larval repair behaviour.
Spatial variations in egg density and the intensity of parasitism in a neotropical chrysomelid (Cephaloleia consanguinea)
Authors: MORRISON GEROLD , STRONG DONALD R. 
Published: March 2008

Abstract.

The chrysomelid beetle, Cephaloleia consanguinea (Hispinae), is a monophagous herbivore of Heliconia imbricata (Zingiberales: Heliconiaceae) in wet lowland forests of eastern Costa Rica.
Within the study area parasitism by eulophids and trichogrammatids (Hymenoptera: Chalcidoidea), the most common source of C. consanguinea egg mortality, varied in intensity from 35% to 50% during 1974–77.
Spatial relationships between the probability of parasitism and egg density per leaf were the net result of two opposing trends. The probability of at least one egg on an egg‐bearing H. imbricata leaf being encountered and parasitized (here termed a ‘discovery’ of that leaf by parasitoids) increased significantly as egg density per leaf increased. The conditional probability of parasitism for other eggs present, given an attack on one egg, decreased with increasing egg density.
The net result was a decrease in the overall probability of parasitism as egg density per leaf increased. Host aggregation appears beneficial in reducing the intensity of parasitoid attacks.
Despite this inverse relationship between the overall probability of parasitism and egg density per leaf, a model based on the binomial distribution provides a good description of the spatial aspects of this host—parasitoid interaction.
Physiological correlates of the availability of Glossina morsitans centralis Machado to different sampling methods
Authors: RANDOLPH SARAH E. , ROGERS D. J. 
Published: March 2008

Abstract.

The feeding cycle for male tsetse flies and the pregnancy cycle for females are used as frameworks for investigating the field behaviour of Glossina morsitans centralis Machado in Zambia, and hence the sampling biases of different capture devices.
Flies were collected in the field using hand nets and an electric back pack on foot patrols, and hand nets, hand‐catching and an electric screen on landrover patrols. They were analysed for wing‐fray, vein‐length, chloroform‐extractable fat and haematin. In addition, samples of laboratory‐bred females killed daily during their second pregnancy cycle were analysed for the last two parameters.
The daily flying time of males is estimated from the fat—haematin curve to be about 32 min/day, which is identical to previous estimates for G. morsitans from Tanzania.
From the varying numbers and fat content of male flies caught by the different sampling methods during the course of the feeding cycle it is concluded that both haematin levels and fat reserves influence fly behaviour.
Comparison of the frequency distribution of wild‐caught and laboratory‐bred females along the corrected residual dry weight axis of the pregnancy cycle suggests that the results of combined electric‐trap and hand‐net sampling reflect the actual frequency distribution in the wild population at least for the first 7 days of the pregnancy cycle; but females in the last 2 days of their pregnancy cycle are apparently unavailable to sampling devices, perhaps because of their reduced flight activity.
The very variable percentage female catch (10.9–43.4%) returned by the different sampling methods is discussed in the light of the detailed analysis of the differential availability of male and female flies to each capture device.
Host searching and oviposition behaviour of some parasitoids of aphidophagous Syrphidae
Authors: ROTHERAY G. E. 
Published: March 2008

Abstract.

An analysis of host searching behaviour suggests that female parasitoids respond to aphid odours bringing them to the region of an aphid colony.
Syrphid hosts are located within the aphid colony by response to contact chemicals on the larval integument.
The behavioural mechanisms used by syrphid larvae to resist attacks and the subsequent responses made by parasitoids are described.
Oviposition behaviour and host size preferences of parasitoids are described.
The adaptive and evolutionary significance of wing polymorphism and parthenogenesis in Ptinella Motschulsky (Coleoptera: Ptiliidae)
Authors: TAYLOR VICTORIA A. 
Published: March 2008

Abstract.

The incidence of wing polymorphism varies seasonally in field populations of Ptinella aptera and Ptinella errabunda with alatae increasing in abundance in summer.
In laboratory cultures of P. aptera alate development varies with temperature. This implies that morph determination is based on a physiological switch sensitive to temperature and possibly other adaptively relevant environmental factors.
Alate P. aptera produce a higher proportion of alate offspring than do apterous parents suggesting an inherited component in polymorphism control, or some form of maternal effect.
The female biased sex ratio expected of a regularly inbreeding species was found only in the alate morph. Apterous beetles show a 1:1 sex ratio which is explained by the females' limited capacity to store sperm, the enormous size of the sperm, and the consequent need for multiple insemination.
Ptinella errabunda is thelytokous but fails to realize the potentially doubled fecundity associated with parthenogenesis. Both the number of eggs produced and their viability is lower than in bisexual congeners.
Enhanced colonizing ability, rather than energy economy, is considered to be the most important selective advantage of parthenogenesis to Ptinella in the subcortical habitat.
The spatial and temporal heterogeneity of the subcortical habitat is considered to have favoured the evolution and maintenance of parthenogenesis and wing polymorphism in Ptinella.
Supercooling points of insects and mites on the Antarctic Peninsula
Authors: BLOCK WILLIAM 
Published: March 2008

Abstract. 1. Mean supercooling points of eleven species of arthropods (three Collembola, seven Acari and one Diptera) ranged from ‐6.2 to ‐9.4°C (high group), and from ‐17.7 to ‐31.0°C (low group). The majority of individuals in the high group had food in their gut systems.2. Freezing was lethal to all species examined except larval Belgica antarctica Jacobs (Chironomidae).3. Glucose, glycerol and mannitol were found in low concentrations in extracts of Ctyptopygus antarcticus Willem (Collembola) and larvae of B. antarcrica; it is udikely that these substances had a major effect on the supercooling of either species.4. Two Collembola species possessed significantly (P< 0.05) lower supercooling points at locations on the Antarctic Pensinsula than at Signy Island, South Orkney Islands. The converse was observed for two species of Acari.5. It is suggested that whilst gross climatic and also micro‐habitat conditions may influence the cold hardiness of such arthropods, especially seasonally, their full supercooling ability is rarely tested.
Biosystematics of the Muellerianella complex (Homoptera, Delphacidae): host‐plants, habitats and phenology
Authors: BOOIJ C. J. H. 
Published: March 2008

Abstract. 1. Ecological differences between closely related species and forms of the planthopper genus MueIlerianella (Delphacidae) were studied.2. In the field M.brevipennis and M.faimairei are restricted to Deschampsia cespitosa and Holcus lanahis/H.mollis. respectively. M.extrusa is mainly found on Molinia caerulea, but has also been recorded from other grass‐species. Triploid all‐female forms which reproduce by gynogenesis usually live on Holcus together with M.fairmairei. Other gynogenetic populations were found on Bromus ramosus, Deschampsia flexuosa and Calamagrostis canescens.3. Breeding experiments showed that the diploid species cannot be maintained on each other's host‐plants, but accept other grass‐species.4. Due to overlapping habitat requirements of the host‐plants, ecological isolation between the Muellerianella species is incomplete.5. M.extrusa lives in bogs, moors and forests on poor acid soil. M.brevipennis is found in forests, carr, fens and in extensively managed grasslands. M.faimairei and associated triploid forms occur mainly in grasslands and other man‐made habitats. The habitats of all three species are usually wet.6. In most parts of Europe M.brevipennis and M.extrusa are monovoltine and M.fairmairei is mostly bi‐or polyvoltine.
Phytophagous insects associated with cadang‐cadang infected and healthy coconut palms in South‐eastern Luzon, Philippines
Authors: ZELAZNY B. , PCA E. PACUMBABA 
Published: March 2008

Abstract. 1. The most common phytophagous insects associated (as adults) with the leaves of coconut palms in the Southeastern part of Luzon have been identified as part of a study on the natural method of spread of cadangcadang disease. Sixty‐three species, of which at least twenty individuals were caught alive or with sticky boards, and five colony‐forming Homoptera are listed. The sixty‐three species belonged to the orders of Orthoptera (two species), Coleoptera (eight species), Hemiptera (one species) and Homoptera (fifty‐two species, mainly Cicadellidae and Derbidae).2. Three beetles (Oryctes rhinoceros, Plesispa reichei and Hemipeplus sp.) and a lace bug (Stephanitis typicus) were found to be significantly more abundant in areas with a high incidence of cadangcadang disease. O.rhinoceros and P.reichei were also significantly more common on old palms (which are predisposed to the disease), and more abundant on cadang‐cadang infected than on neighbouring healthy palms. Hemipeplus sp. apparently feeds by scraping the cuticle layer of the youngest fronds.
Effects of inundation and salt on the survival of ants in a sandy coastal plain
Authors: BOOMSMA J. J. , ISAAKS J. A. 
Published: March 2008

Abstract. 1. Survival of four species of ants, Myrmica rubra, Myrmica scabrinodis, Lasius niger and Lasius flavus, exposed to prolonged inundation and the drinking of brackish water, was experimentally determined.2. In most of the experiments, survival of Lasius flavus workers was much worse than either Lasius niger or Myrmica scabrinodis.3. After inundation with brackish water, and drinking of brackish water for more than 3 weeks, survival of workers of Myrmica rubra was also more affected than that of Lasius niger and Myrmica scabrinodis.4. As a rule, survival of dealated queens after inundation appeared to be better in Lasius flavus and Lasius niger, but worse in Myrmica rubra, compared with worker survival.5. After surviving inundation, the capacity to produce eggs and workers was only slightly affected in queens of both Lusius species.6. The conclusions based on the experimental mortality rates seem to be consistent both with ant species distribution and with frequency of inundation and salt stress in different parts of the coastal plain and surrounding sand‐dunes on the Dutch Wadden island Schiermonnikoog.
The ‘edgeeffect’ in butterfly oviposition: causality in Anthocharis cardarnines and related species
Authors: COURTNEY STEVEN P. , COURTNEY SARAH 
Published: March 2008

Abstract. 1. An ‘edge‐effect’, where outlying host plants receive proportionately most attention from insect herbivores, is described from the literature, and from data on Anthochoris cardamines (L.), in northern England.2. Six hypotheses are examined as explanations for the effect in A.curdamines. Four are shown to be refuted by studies on female behaviour and the survival of larvae.3. It is argued that the ‘edge‐effect’ comes about due to two or more aspects of the searching behaviour of females. The effect may be seen as an outcome of behaviour adapted to searching for host plants of low density.
Temperature effects in relation to the patterns of distribution and abundance of three species in the Drosophila affinis subgroup
Authors: FOGLEMAN JAMES C. 
Published: March 2008

Abstract. 1. The effect of temperature on several aspects of the biology of Drosophila affinis, D.algonquin and D.athabasca were investigated in order to gain insight as to why these closely related species differ in their spatial and temporal patterns of occurrence.2. No differences exist between the three species in the effect of temperature on egg hatchability.3. Productivities of the three species were measured in a temperature gradient device. These measurements indicated that D.athabasca has an advantage in productivity over D.affinis at cooler temperatures (below 25°C). At warmer temperatures (above 25°C) the greater productivity of D.affinis makes it the better species. Drosophila algonquin, like D.athabasca, was characterized by its productivity curve as a species more adapted to cooler climates.4. The competitive abilities of the three species were measured at 25°C, at 18°C, and in an environment which fluctuated between 18 and 25°C on a daily cycle. Competitive ability was estimated on the basis of the performance of the species in two‐ and three‐species populations.5. In general, D.affinis exhibited its highest competitive ability relative to the other two species at the highest experimental temperature. D.athabasca had its highest competitive ability at the lowest temperature. The competitive ability of Ddgonquin was intermediate; less than that of D.affinis but greater than D.athabasca.6. The dependence of competitive ability and productivity on temperature is thought to be partly responsible for the differences between the species with respect to their geographic distributions and their spatial and temporal patterns in natural populations.
Seasonal patterns in species richness of herbivores: Macrolepidopteran larvae on Finnish deciduous trees
Authors: NIEMELÄ PEKKA 
Published: March 2008

Abstract. 1. The seasonal distribution of macrolepidopteran species richness on Finnish deciduous trees vaned from positively skewed (peak in spring) to negatively skewed (peak in autumn).2. The skewness values of species richness had a significant negative correlation (r = ‐ 0.98) with the duration of the seasonal shoot‐growth period of the tree species.3. Trees which complete their shoot growth early in the season (Quercus type) produce new leaves only during spring, while trees whose shoot growth continues to autumn (Populus type) do so throughout the summer.4. Consequently, there is a difference in the number of available resources in the late summer foliage of different tree species, Trees ceasing leaf production early such as oak (Quercus robur) and bird cherry (Prunus padus) have one major resource type (mature leaves) in late‐season foliage while trees like birches and alders have two Ooung and mature leaves).5. Because young leaves formed late in the season are preferred to mature ones by some species of herbivores and because other species prefer mature leaves at the same time, the species richness of Populus‐type trees is higher later in the season than the species richness of Quercus‐type of trees, which have just one type of resource available.