bluuebunny/crossref_metadata_2025 huggingface dataset:
Life cycle and seasonal dynamics of Cucullanus cirratus O.F. Müller, 1777 (Nematoda, Ascaridida, Seuratoidea, Cucullanidae) in Atlantic cod, Gadus morhua L.
Authors: Køie Marianne
Published: April 2011

Mature specimens of Cucullanus cirratus O.F. Müller, 1777 (Cucullanidae) were obtained from the pyloric caeca and intestine of Atlantic cod, Gadus morhua L., from Danish waters. Eggs embryonate in seawater. Third-stage larvae about 400 µm long, with amphids and dereids, hatch from the egg. Experimental studies indicated that third-stage larvae were infective to calanoid and cyclopoid copepods and sand gobies, Pomatoschistus minutus (Pisces, Gobiidae). Larvae entered the haemocoel of copepods but did not grow. In gobies, the third-stage larvae entered the intestinal mucosa and grew to 800 µm in length within 6 months. They were not encapsulated. Experimental infections of cod (8-30 cm long) showed that free-living third-stage larvae are not infective, whereas >700 µm long third-stage larvae from gobies survived in the cod. Third-stage larvae 700-1200 µm long occur in the stomach mucosa, where they develop and moult to fourth-stage larvae. The fourth-stage larvae then migrate to the pyloric caeca and anterior part of the intestine, where they moult and develop to the mature adult stage. No developmental stage became encapsulated. Naturally infected cod (>20 cm total length) harboured moulting third-stage larvae and <2 mm long fourth-stage larvae 2 months post capture. Naturally infected 4- to 5-month-old codlings (8-10 cm total length) harboured 2-3 mm long fourth-stage larvae only, indicating that they acquired the third-stage larvae as planktivorous fry only a few centimetres long. Cucullanus cirratus may have a life-cycle that involves copepod transport hosts and fish (gobies or cod fry) intermediate hosts. Postcyclic development occurs in gadoids when an infected cod is consumed by another cod (cannibalism). Examinations of 350 (8-78 cm total length) naturally infected cod showed that group 1 and older cod are infected throughout the year, with maximum prevalence of third-stage larvae in spring and summer. The greatest prevalence of gravid worms was observed in autumn.
Role of chemical communication and behavioural interactions among conspecifics in the choice of shelters by the cave-dwelling salamander Proteus anguinus (Caudata, Proteidae)
Authors: Guillaume O
Published: April 2011

Non-sexually active males and females of the cave-dwelling salamander Proteus anguinus always aggregate in the same shelters, either under stones or in fissures. However, it was not known if this behaviour results from chemical communication and (or) behavioural interactions among conspecifics. I tested the hypothesis that this is the case by using two-choice tests. The results showed that salamanders re-located their own shelter even when it was displaced. However, they preferred a shelter that belonged to a conspecific or contained faecal pellets of a conspecific to their own or a control "blank" shelter. When two salamanders were simultaneously given the choice between two blank shelters, they cohabited. When they were simultaneously given the choice between their own shelter and each other's, they used them indiscriminately and frequently cohabited. These data provide evidence that P. anguinus use chemical signals as directional cues for homing and also for social behaviour. Chemical signals may attract conspecifics, which subsequently may exhibit gregarious behaviour by occupying common shelters.
Kin discrimination in juvenile brook trout (Salvelinus fontinalis) and the effect of odour concentration on kin preferences
Authors: Hiscock Martha J , Brown Joseph A
Published: April 2011

Kin discrimination abilities have been demonstrated in juveniles of many salmonid species. In this study, two experiments were conducted to determine: (i) if juvenile brook trout (Salvelinus fontinalis) have the ability to discriminate kin based on chemosensory cues and (ii) the effect that odour concentration has on an individual's preference. In the first experiment, individuals spent more time in water conditioned by kin than in water conditioned by non-kin, indicating that juvenile brook trout have the ability to discriminate kin based on chemosensory cues. Individuals in the second experiment based preferences on both concentration and kinship. When odour concentrations were equal, individuals preferred water conditioned by kin over that conditioned by non-kin. However, if given a choice between high and low concentrations, individuals preferred the high concentration independent of kinship. Individuals may perceive the various odour concentrations as an indicator of shoal size and base preferences on these differences.
The dynamics of hazel grouse (Bonasa bonasia L.) occurrence in habitat fragments
Authors: Åberg Johan , Swenson Jon E , Andrén Henrik
Published: April 2011

The aim of this study was to evaluate the effects of habitat fragment size and isolation on the dynamics of hazel grouse (Bonasa bonasia L.) occurrence. Habitat fragments surrounded by nonhabitat coniferous forest, in an intensively managed forested landscape, were censused during seven seasons. None of the 33 habitat fragments were occupied in all seven seasons and 7 were never occupied. Turnover occurred in 79% of the habitat fragments. The most common occupation of a habitat fragment was by only one hazel grouse male (84%). Thus, the dynamics of hazel grouse occurrence in the habitat fragments was basically monitored on the scale of individuals. Large and less isolated habitat fragments with a high amount of cover were occupied significantly more often than small, isolated fragments. The effect of size appeared most clearly when analyzing the total number of hazel grouse occupying a habitat fragment. The appearance of hazel grouse in the habitat fragments was best explained by the amount of cover, distance to the nearest suitable habitat, and size of the habitat fragment. The effects of interfragment distance on the occurrence and appearance of hazel grouse implies that the habitat has become functionally disconnected for hazel grouse and suggests that the amount of suitable hazel grouse habitat left in this landscape has fallen below a critical level.
The ultrastructure of glands and the production and function of the secretion in the adhesive capture apparatus ofStenusspecies (Coleoptera: Staphylinidae)
Authors: Kölsch Gregor
Published: April 2011

The elongated labium of rove beetles of the genus Stenus forms an adhesive capture apparatus that enables them to catch fast-fleeing prey such as Collembola. The adhesion is mediated by a secretion produced in glands within the head capsule and secreted onto the paraglossae. Transmission electron microscopy has revealed that these "adhesive glands" are composed of discrete gland units, each consisting of three cells. Two cells are secretorily active, each producing a different secretion, one proteinaceous and the other lipoid. Consequently, a two-phase secretion can be found on the surface of the paraglossae. Adhesive glands and normal epidermal glands share several characteristics and are therefore considered to be homologous. Structural differences can be functionally interpreted. The long glandular ductules themselves serve as a reservoir for the secretion before it is expressed prior to the predatory strike. Van der Waals forces and both the surface tension and the viscosity of the adhesive secretion are discussed as possible mechanisms of adhesion. The adhesion resulting from the viscosity of the fluid is the strongest and exceeds the force theoretically required for catching collemboles.
Demography and body condition of coyotes (Canis latrans) in eastern New Brunswick
Authors: Dumond M , Villard M -A
Published: April 2011

We documented the demography and body condition of coyotes (Canis latrans), using 77 carcasses collected in late fall and winter (1995-1996 and 1996-1997) during an increase in snowshoe hare (Lepus americanus) density in eastern New Brunswick. We compared body condition at the beginning (November-January) and end of winter (February-March) in relation to breeding status. Physical characteristics of coyotes were similar to those reported elsewhere in the northeastern portion of its range. The sex ratio did not differ significantly from 1:1. The population was unusually old (5.6 ± 0.4 years of age (mean ± SE)). The parturition rate was low (40.9% in adult females), and placental scars were present only in females >5 years old (6.6 ± 0.6 scars per female). There was no significant decrease in the body condition of adult females over the winter but the body mass of those females with placental scars tended to decrease over the winter (P = 0.012). Also, during November-January, reproductive females (with placental scars) were significantly heavier (P = 0.007) than non-reproductive adult females (without placental scars). Our results suggest that in the coyote populations in eastern New Brunswick, breeding status and reproductive costs should be taken into account in future studies of demography and body condition. Also, the low level of coyote exploitation by humans may be responsible for the old age structure of the population and the low parturition rate. The exploitation level should be considered when analyzing coyote sociodemographic data.
Male amphipods increase their mating effort before behavioural manipulation by trematodes
Authors: McCurdy Dean G , Forbes Mark R , Boates J Sherman
Published: April 2011

Certain parasites appear to alter the behaviour of intermediate hosts, making them more susceptible to predation by final hosts (adaptive parasite manipulation). In some cases, however, hosts are expected to respond by increasing their reproductive effort when first parasitized (adaptive host response). We tested predictions of these two hypotheses for males of the amphipod Corophium volutator (Pallas). Consistent with adaptive parasite manipulation, males infected by the trematode Gynaecotyla adunca (Linton) were likely to crawl on the surface of a mud flat, but only when visual predation by the final host, semipalmated sandpipers, Calidris pusilla L., was likely (during the day), and after trematodes had developed to their infective stage. Males appeared to compensate for parasitism by being more likely to mate, and perhaps by increasing ejaculate size. However, parasitized males that mated when first infected were less likely to mate again once their parasites reached their infective stage, despite their increased crawling at that time, which is associated with mate searching. We did not find that trematodes reduced host survival, apart from expected increases in predation rate on amphipods; in fact, highly infected amphipods actually lived longer than lightly infected ones. Taken together, our results suggest that adaptive host responses can occur before parasite manipulation is realized.
Habitat selection and use of edges by striped skunks in the Canadian prairies
Authors: Larivière Serge , Messier François
Published: April 2011

During 1993-1994, we radio-tracked 21 female and 5 male striped skunks (Mephitis mephitis) in south-central Saskatchewan, Canada, to assess their patterns of habitat selection. Home ranges of both sexes contained more areas managed for nesting waterfowl and less woodland than the overall study area. When foraging within their home ranges, striped skunks used more wetland and woodland and less cropland relative to other habitat types (managed nesting areas, rights-of-way, farmsteads). Patterns of habitat selection by striped skunks were significantly but weakly correlated with abundance of insects and small mammals. Striped skunks selected undisturbed habitats where ground litter can accumulate, possibly because such habitats also harbor a greater abundance of prey. Our results support the restoration of grasslands for nesting waterfowl. Furthermore, the use of large habitat patches by striped skunks decreased away from edges, suggesting that large patches may serve as refuges for ground-nesting birds.
Hemolymph homeostasis in relation to diel feeding activity and microclimate in the prototypal land isopodLigia pallasii
Authors: Carefoot Thomas H , Wright Jonathan , Pennings Steven C , Ziegler Andreas , Zimmer Martin , Uglow Roger F , Danford Angela R , Danko Jean Paul
Published: April 2011

Twenty-four-hour variability in hemolymph osmolality was assessed in a field population of the semiterrestrial isopod Ligia pallasii and related to feeding activity and microenvironmental conditions of relative humidity (RH) and temperature in the species' habitats. Hemolymphs were also analyzed for levels of ammonia and glucose as indicators of digestive and absorptive activities. Comparative data on hemolymph osmolality and microhabitat conditions were also obtained for several ligiid species in Hawai'i. Late-morning peaks in hemolymph osmolality in L. pallasii were coincidental with peaks in ammonia and glucose and with predicted times of digestion/absorption based on observed feeding activity in the population, suggesting that the elevations in osmolality were due to salt-loading from the species' seaweed diet. Uniformity of microenvironmental conditions of RH and temperature in Ligia's supralittoral habitat, whether temperate or tropical, and regardless of time of day or localized weather conditions, suggests that dietary salt-loading is likely the greatest challenge to osmotic homeostasis in ligiids. This feature and other aspects of hemolymph osmolality in ligiids are discussed in the context of colonization of land by prototypal terrestrial isopods.
Sperm-cell ultrastructure of North American sturgeons. III. The lake sturgeon (Acipenser fulvescens Rafinesque, 1817)
Authors: DiLauro Martin N , Kaboord Wayne S , Walsh Rosemary A
Published: April 2011

Lake sturgeon (Acipenser fulvescens) sperm cell fine structure was examined using transmission electron microscopy. The cell possesses a distinct acrosome, a defined head region, a midpiece, and a single flagellum. Sperm cells of this species share a general radial symmetry, an elongate shape, a distinct acrosome, and the presence of endonuclear canals with those of other sturgeons. The mean length of the lake sturgeon sperm cell body (acrosome + nucleus + midpiece) is approximately 7.13 µm and the length of the flagellum is about 50 µm, resulting in a total cell length of about 57 µm. The lake sturgeon sperm cell is much longer and slightly wider than that of the Atlantic sturgeon. The sperm-cell nuclei of lake, shortnose, white, and stellate sturgeons are elongate trapezoids in shape, with the anterior (acrosome) end narrowest but, in the Atlantic sturgeon, the anterior portion of the trapezoid is wider than the posterior. Although slightly smaller in total length and width, the lake sturgeon sperm cell is most similar to the shortnose sperm cell in ultrastructure, overall size, and shape; it also shares similarity of shape with the stellate and white sturgeon sperm cells. The cell nuclei of these four sturgeons have three endonuclear canals. The acrosome of the lake sturgeon sperm cell has longer posterolateral projections than that of the Atlantic or shortnose sturgeon sperm cell. A structural connection, the fibrous body, is present in the lake sturgeon sperm cell between the nuclear fossa and the proximal centriole, as in the Atlantic and shortnose sturgeon sperm cells. Our results suggest a more recent evolutionary linkage between the lake and shortnose sturgeons than with the Atlantic sturgeon. This work presents the first ultrastructural description of the lake sturgeon sperm cell.
Egg size variation as a function of environmental variability in parasitic trematodes
Authors: Poulin Robert , Hamilton William J
Published: April 2011

Environmental predictability is often assumed to select for variability in egg size or offspring size, since a greater variance in offspring size may insure that, on average, a greater proportion of offspring will survive whatever the conditions experienced. In a comparative analysis across 747 species of parasitic trematodes, we examined the relationship between intraspecific variability in egg size and three predictors of environmental stability: the type of definitive host, the type of habitat in which parasite eggs are released, and latitude. Although trematode species using ectothermic hosts and (or) releasing eggs in terrestrial habitats tended to have more variable egg sizes than species using endothermic hosts and (or) releasing eggs in water, the trend was not significant, even when controlling for phylogenetic influences. Latitude correlated strongly and negatively with variability in egg sizes among trematode species releasing their eggs in terrestrial habitats, whether or not phylogenetic effects were removed. No relationship was found among species releasing their eggs in water. We propose that spatial heterogeneity of the external environment, and not its temporal stability, has played an important role in shaping intraspecific variability in egg sizes in parasitic trematodes.
Food-web dynamics and trophic-level interactions in a multispecies community of freshwater unionids
Authors: Nichols S J , Garling D
Published: April 2011

We compared feeding habits and trophic-level relationships of unionid species in a detritus-dominated river and an alga-dominated lake using biochemical analyses, gut contents, and stable-isotope ratios. The δ13C ratios for algae and other food-web components show that all unionids from both the river and the lake used bacterial carbons, not algal carbons, as their main dietary source, in spite of positive selection and concentration of diatoms and green algae from the water column in the gut and mantle cavity. Algae did provide key nutrients such as vitamins A and D and phytosterols that were bioaccumulated in the tissues of all species. The δ15N ratios for the multispecies unionid community in the Huron River indicated some differences in nitrogen enrichment between species, the greatest enrichment being found in Pyganadon grandis. These δ15N ratios indicate that unionids may not always feed as primary consumers or omnivores. Stable-isotope data were critical for delineating diets and trophic-level interactions of this group of filter-feeders. Further refinements in identifying bacterial and picoplankton components of the fine particulate organic matter are needed to complete our understanding of resource partitioning between multispecies unionid populations.
Predator size and distance to edge: is bigger better?
Authors: Ferguson Steven H
Published: April 2011

I investigated the use of edge by soil arthropods by testing whether mesoarthropod predators were closer to edge than expected and whether large predators were closer to edge than small predators. The experimental design consisted of 120 boxes, each covering 200 cm2of soil, that were randomly distributed within a 0.13-km2aspen stand located in the Canadian prairie region. Each 2-kg box depressed the leaf litter, creating a microhabitat island for soil arthropods consisting of 61 cm of edge. During 20 weekly surveys from May to September in 1997 and 1998, numbers and distribution of arthropods located immediately beneath the boxes were recorded. Mesoarthropod predators were found closer to edge than expected. Centipedes, beetle larvae, and predatory mites (Acari) were found at intermediate distances to edge, whereas beetles, ants, adult flies, bugs, and spiders were distributed adjacent to edge. Generally, larger mesoarthropod predators were found closer to edge than smaller individuals, within each taxonomic group. Collembola, the major mesofauna prey, were distributed randomly with respect to edge during wet periods of high density. During the subsequent dry periods, reduced densities of Collembola occurred and distribution became skewed, with greater numbers in interior areas and reduced densities near edges. Temperature and moisture under the boxes did not vary with distance to edge, although the microclimate was cooler and more humid under the experimental boxes relative to beyond the boxes. These results support the hypotheses that mesoarthropod predators forage along box edges (i.e., linear corridors) and that larger individuals may gain access to edge owing to their larger size, although alternative explanations are possible, depending on the particular taxonomic group.
Fine-scale temperature effects on cricket calling song
Authors: Martin Shannon D , Gray David A , Cade William H
Published: April 2011

The effects of temperature on the structure of cricket calling song were examined in the trilling field cricket Gryllus integer. A repeated-measures design was used to assess the effects of temperature and individual differences among males simultaneously. Temperature affected most aspects of calling song, specifically pulse length, interpulse length, peak frequency, trill length, intertrill length, and pulse duty cycle. Unaffected by temperature were the number of pulses per trill, the proportion of pulses missed within a trill, and the trill duty cycle. After controlling for temperature, significant individual differences among crickets were found in peak frequency, number of pulses per trill, trill length, and intertrill interval. Both the environmental and individual, that is, possibly genetic, influences on calling song may influence sexual communication in this species.
Enhancing Our Community of Inquiry: Thoughts on Principles and Best Practices in Research With Deaf and Hard of Hearing Individuals
Authors: Ryan John F.
Published: April 2011

The beginning of a new editorship for the Annals provides a good opportunity to re-engage contributors and the readership in a conversation about the principles and standards for manuscripts submitted to the Annals . In turn, the hope is that this conversation might help to enhance our research community and therefore the Annals’ contributions to knowledge and understanding across an array of research and areas of inquiry focused on d/Deaf and hard of hearing individuals.
Social-Emotional Functioning of Elementary-Age Deaf Children: A Profile Analysis
Authors: Vogel-Walcutt Jennifer J. , Schatschneider Christopher , Bowers Clint
Published: April 2011

Discussion and study of the social-emotional development of deaf and hard of hearing children, though extensive, has yet to provide an accurate understanding of the differences between deaf and hearing children. Consequently, the goal of the researchers was to conduct a profile analysis to determine similarities and differences between the two groups. The sample consisted of 20 hearing and 20 deaf children ages 8–11 years. All of the deaf children were enrolled in a Simultaneous Communication magnet program. Significant differences were found in two areas: school interest and on-task behavior. Overall, however, data from the study showed few differences between hearing and deaf children. The researchers recommend that current interventions be reconsidered on the basis of these results.
Traces of Good in Plotinus's Philosophy of Nature: Ennead VI.7.1-14
Authors: Thaler Naly
Published: April 2011

The paper explores Plotinus's discussion in VI.7 of the place of teleological explanations in biology. The paper's main claim is that although Plotinus argues in the first three chapters that the use of teleological explanations is incompatible with the priority of Intellect over the physical world, his ultimate aim is not to prohibit the appeal to notions such as utility and benefit in the study of nature. Rather, in the first fourteen chapters of the treatise Plotinus attempts to show that not only animal organs, but their utility and benefits as well have their origin in Intellect.
Aristotle's "Is Said in Many Ways" and Its Relationship to His Homonyms
Authors: Brakas Jurgis (George)
Published: April 2011

Being, Aristotle says, "is said in many ways" (λέγεται πολλαχώς), and so are the good and many other fundamental things. Fair enough, but what does this mean ? While scholars have presented us with an array of different translations for this difficult term, none seem adequate. I argue that it means "is uttered signifying many things." I then examine the relationship of this phrase to his homonyms, to significata having the same "name" that are "related to one and the same thing" (πρὸς ἒν), and to "is said homonymously" (λέγεται όμωνύμως). The result is a new view of Aristotle's λέγεται πολλαχῶς, his homonyms, and their relationship to each other.
"To Raise Them to an Equal Participation": Early National Abolitionism, Gradual Emancipation, and the Promise of African American Citizenship
Authors: Polgar Paul J.
Published: April 2011

The first organized abolition movement in America championed black citizenship and incorporation into the greater body politic instead of colonization or exclusion from the civic sphere of the fledgling nation. The same natural rights Revolutionary ideology that made American antislavery possible also presented slaves themselves as the very antithesis of the independent, virtuous citizenry necessary to uphold representative government and maintain the new nation's experiment in republicanism; therefore making abolition itself a problematic process. Out of their quest to solve this paradox, early national abolition society members advocated gradual emancipation coupled with a program of free black uplift based on the tenets of environmentalism and the diffusion of republican educational mores. Through these reformist initiatives, abolition societies sought to prove black capacity for freedom by gradually integrating African Americans into the American republic and making them virtuous and independent citizens, fully capable of productively exercising their liberty within greater white society. Predicated on an enlightenment idealism that viewed white prejudices towards blacks as conquerable, antislavery societies believed that their abolitionist program would disprove a principle argument against slave emancipation: African Americans' alleged incapacity for freedom. Thus for early national antislavery activists the movement to abolish slavery and the cultivation of African American citizenship were inextricably interwoven. Although abolition societies of this period ultimately failed in overturning white prejudice and integrating former slaves into American society as equal citizens, they did establish several guiding principles of antislavery reform that later abolitionists would inherit long after Northern emancipation was achieved.
Is There Early Recognition between Penelope and Odysseus?; Book 19 in the Larger Context of the Odyssey
Authors: Louden Bruce
Published: April 2011

The larger context of the Odyssey repeatedly portrays all manner of individuals, no matter how astute, even the goddess Circe, as unable to recognize Odysseus when he is before them. This is the poem's favorite use of irony, and is also related to the thematic use of theoxenic myth, in which mortals fail to recognize that the unknown guest before them is a god in disguise. The Odyssey has the verbal formulas to depict a character who does recognize in disguise, but deliberately withholds this information from others: Telemachos at 1.420.
Penelope and Early Recognition: Vlahos, Harsh, and Eustathius
Authors: Yamagata Naoko
Published: April 2011

Vlahos eloquently enhances Harsh's thesis that Penelope recognises Odysseus as early as in Odyssey book 19. While accepting the viability of this interpretation, this article attempts to explore some details of Vlahos's argument which call for clarification. It agrees with Vlahos in that Odysseus's declared intention to "provoke further" Penelope and the maidservants ( Od . 19.45) compels us to look for the first occasion on which Odysseus "provoked" them. However, it does not agree with his assumption that the first occasion is when the beggar-Odysseus refuses to come to Penelope when summoned, but rather argues that it is when he provokesAntinous to cause disturbance which in turn attracts the attention of Penelope and her maidservants. This article also challenges Vlahos' newly proposed interpretations of some passages such as Melantho's "mega ergon" ( Od . 19.91-92), Telemachus's objection to Odysseus's plan ( Od . 16.311-12) and the implication of Penelope's death wish in the morning of the bow contest ( Od . 20.60-90).
Mapping NASCAR Valley: Charlotte as a Knowledge Community
Authors: Mitchelson Ronald L. , Alderman Derek H.
Published: April 2011

Las pasadas dos décadas han presenciado un rápido crecimiento en la popularidad de las carreras de automóviles y su principal órgano sancionador, NASCAR. Mientras que el consumo del espectáculo del día de la carrera es cada vez más disperso, la producción de este deporte muestra una geografía muy diferente; una construida sobre una creciente aglomeración en vez de descentralización. Nos referimos a la agrupación de la localización de actividades industriales de carreras de autos en y alrededor de la región de Charlotte como "Valle de NASCAR", un término inspirado en una concentración similar de las empresas regionales relacionadas con las carreras en el sur de Inglaterra, llamado Valle de Deportes de Motor. Demostramos que la aglomeración fue apenas accidental. El Valle de NASCAR se muestra como una región uniforme claramente definida justo al norte de Charlotte, con un eje principal que corre hacia el noroeste-sureste de Mooresville a Concord, Carolina del Norte. El Valle contiene aproximadamente la mitad de los establecimientos de carreras del estado, 60 por ciento del empleo relacionado a las carreras, y 70 por ciento de los ingresos de carreras. Este trabajo empírico confirma algunas expectativas claves asociadas a la creación de comunidades de conocimiento en las cuales dominan las tecnologías de ingeniería. En primer lugar, estas comunidades son espacialmente coherentes. El Valle de NASCAR está altamente regionalizado, con sorprendentemente pocos agujeros e islas. En segundo lugar, la expresión espacial de tal comunidad de conocimiento no es grande. Estimamos que el Valle de NASCAR no se extiende por más de 400 millas cuadradas. En tercer lugar, la expresión espacial de dicha industria, no está bien explicada por referencias a listas tradicionales de sitios y factores situacionales. Estadísticamente, la respuesta adecuada a "¿dónde?" reside en referencia a las economías de escala externa.
Drought and Other Driving Forces behind Population Change in Six Rural Counties in the United States
Authors: Maxwell Justin T. , Soulé Peter T.
Published: April 2011

Los posibles impactos del cambio climático en los patrones de población postindustriales en los Estados Unidos han sido ampliamente ignorados. En este estudio examinamos los cambios demográficos en seis condados rurales de tres regiones diferentes en los Estados Unidos. Además de determinar el papel de las variables tradicionales que se conoce influyen en los cambios demográficos, también examinamos la posible influencia de la sequía, medida por el estudio de . Utilizamos análisis de correlación y regresión para determinar las fuerzas que impulsan los cambios demográficos en cada caso de estudio de condado. Las variables tradicionales explicaron la mayoría de los cambios demográficos. Sin embargo, aunque la sequía explicó un pequeño porcentaje de variación de la población, fue significativo en tres de los seis condados y en cada región que examinamos. Espacialmente, con la excepción de las variables climáticas, los condados dentro de la misma región tienden a tener similares fuerzas propulsoras del cambio de población.
FUNGUS DISEASES AFFECTING ADELGES PICEAE IN THE FIR FOREST OF THE GASPÉ PENINSULA, QUEBEC
Authors: Smirnoff W. A.
Published: April 2011

In 1966–67, the following fungi were isolated on Adelges piceae (Ratz.), a serious pest on fir trees in the Gaspé Peninsula: Fusarium larvarum, Cephalosporium coccorum, Entomophthora sp., Aspergillus fumigatus, Aspergillus nigra, Penicillium thomii, Penicillium sp., Cladosporium sp., Isaria farinosa, and Beauveria sp. F. larvarum showed more evidence of pathogenicity for Adelges, while C. coccorum was considered a facultative pathogen. There were not enough cases of infection by Isaria, Beauveria, and Entomophthora to determine their activity. Remaining species were saprophytic. Pathogenicity tests were conducted in the field with F. larvarum and C. coccorum. The fungi were introduced in the population by spraying or dusting, or by mites. However, a variety of external factors made it impossible to determine accurately the degree of virulence of these fungi for Adelges.
REVIEW OF THE GENUS HETEROTARSONEMUS (ACARINA: TARSONEMIDAE)
Authors: Lindquist Evert E.
Published: April 2011

The generic concept of Heterotarsonemus Smiley is reviewed and redefined. The type-species, H. lindquisti Smiley, is redescribed and illustrated along with a new species, H. bicornis; the only described European species, H. coleopterorum Schaarschmidt new combination, is compared with the above two nearctic species. The known species of this genus are associates of bark beetles in conifers.
THE EFFECT OF MATING AND THE PRESENCE OF THE MALE AMBROSIA BEETLE, TRYPODENDRON LINEATUM, ON "SECONDARY" ATTRACTION
Authors: Nijholt W. W.
Published: April 2011

The "secondary" attraction occurring after log attack by the female ambrosia beetle, Trypodendron lineatum (Oliv.), and the reduction in attractiveness after males arrive on the log are not dependent directly on mating. The reduction seems to be associated with the males’ presence, which suggests that they produce a masking substance.
CANNIBALISTIC INFANTICIDE IN SOCIAL HYMENOPTERA RELATED TO ADULT CASTE RATIOS
Authors: Flanders S. E.
Published: April 2011

A review of the literature published during the past 80 years concerning caste differentiation and caste ratios in the social Hymenoptera reveals considerable evidence that caste is determined trophogenically in the embryo (alimentary castration) rather than in the larval instars and that the caste ratios of the embryonic populations in well-established colonies are soon modified by worker action, i.e. selective cannibalization of queen-biased eggs and young larvae, in order to establish the caste ratios of the adult population that are essential to the economy of the colony.
EFFECTS OF THE ANTIFEEDING COMPOUND AC 24055 (4′-(3,3-DIMETHYL-1-TRIAZENO) ACETANILIDE) ON LARVAE AND ADULTS OF DROSOPHILA MELANOGASTER (DIPTERA: DROSOPHILIDAE)
Authors: David J. , Loschiavo S. R.
Published: April 2011

The antifeeding compound AC 24055 (4′-(3,3-dimethyl-1-triazeno) acetanilide) was added to the diet of Drosophila melanogaster at several concentrations. Larval mortality and the duration of larval development increased significantly with increasing concentration from 125 to 625 parts per million (p.p.m.), and these effects were the same in males and females. Within this range of concentrations the weight of recently emerged adults declined with increasing concentration, the loss being greater for females than males. Egg production declined with increased concentration from 200 to 1000 p.p.m., particularly during the second week of egg production. Egg hatchability was not affected at 200 p.p.m., but from 400 to 1000 p.p.m. it declined rapidly from the second to the sixth day; with continued exposure, fertility was partly restored. The life span of adults decreased as the concentration increased from 500 to 1500 p.p.m. Concretions were observed in the Malpighian tubules of females reared in food containing 400 p.p.m. or more of the compound, but not in males.
SAMPLING METHODS FOR ESTIMATING THE ABUNDANCE AND DISTRIBUTION OF ALL LIFE STAGES OF THE APPLE MAGGOT, RHAGOLETIS POMONELLA (DIPTERA: TEPHRITIDAE)
Authors: Cameron P. J. , Morrison F. O.
Published: April 2011

Sampling techniques for all life stages of the apple maggot, Rhagoletis pomonella (Walsh), were developed and their precision and accuracy evaluated. Reliable estimates were obtained for the egg and larval stages (standard error < 10%), but at the low population levels often encountered in the pupal and adult stages it was necessary to accept a lower level of precision (S.E. ≏ 25%). Eggs and larvae were uniformly distributed within trees. Variation between tree quadrants, and sections at different radii from the trunk, showed that stratification within trees was necessary for reliable estimation of the later stages. Predators acting in a heterogeneous environment under the trees were considered to be the major contributors to this variation. The most consistent source of variation was that between trees.
TEN NEW SPECIES OF BAT FLIES OF THE GENUSTRICHOBIUS(DIPTERA: STREBLIDAE)
Authors: Peterson B. V. , Hůrka K.
Published: April 2011

Ten new species ofTrichobiusare described from the Neotropical Region:T.intermedius(Dominican Republic, Haiti, Bahama Islands, Cuba, Jamaica, Puerto Rico, Virgin Islands, Lesser Antilles, Mexico, Guatemala, Honduras, and El Salvador);T.neotropicus(Dominican Republic);T.cognatus(Dominica and Cuba);T.wenzeli(Cuba);T.dusbabeki(Cuba);T.cernyi(Cuba);T.frequens(Cuba, Dominican Republic, and Jamaica);T.macroti(Cuba and Bahama Islands);T.robynae(Puerto Rico); andT.dominicanus(Dominican Republic).
ON THE SYNONYMY OFTARSONEMUS WAITEIBANKS,T.SETIEREWING, ANDT.BAKERIEWING, WITH REDESCRIPTION OF SPECIES (ACARI: TARSONEMIDAE)
Authors: Lindquist Evert E.
Published: April 2011

Tarsonemus waiteiBanks, 1912,T.setiferEwing, 1939, andT.pauperoseatusSuski, 1967, are shown to be conspecific (new synonymy).Tarsonemus bakeriEwing, 1939, thought to be conspecific withT.setiferfor the last 25 years, is shown to be specifically distinct. Both sexes of these species are redescribed and reillustrated, and character state variability expressed within populations ofT.waiteiis discussed. Thewaiteispecies group, previously called thepauperoseatusgroup, is redescribed for these and other species. A provisional key to the known member species of this group is given. This group is judged to be insufficiently distinct from some of the other species ofTarsonemusto warrant recognition as a subgenus.
RESPONSES TO PROSTEPHANUS TRUNCATUS (COLEOPTERA: BOSTRICHIDAE) AND TRIBOLIUM CASTANEUM (COLEOPTERA: TENEBRIONIDAE) TO GAMMA RADIATION FROM 60Co
Authors: Adem Esbaide , Uribe R.M. , Watters F.L.
Published: April 2011

The radiosensitivity of Prostephanus truncatus (Horn) and Tribolium castaneum (Herbst) to 60Co radiation was determined at doses of 5 to 100 krad. P. truncatus was more radiosensitive than T. castaneum at 5, 15, and 25 krad (P < 0.05) at 8 and 16 days after irradiation but after 24 days all individuals irradiated at 15 and 25 krad were dead. At 50 or 100 krad all individuals of both species died in 16 or 12 days, respectively. Dose rates of 1.07 to 12.84 krad/min for a total delivered dose of 25 krad had no effect on the speed of lethal response. The results indicate that on economic grounds alone, it may not be justified to use 50 or 100 krad to accelerate the onset of death by 8 or 12 days, respectively.
A NEW SPECIES OF TELENOMUS (HYMENOPTERA: SCELIONIDAE), AN EGG PARASITE OF THE AMBUSH BUG, PHYMATA SP. (HETEROPTERA: PHYMATIDAE)
Authors: Masner Lubomir , Johnson Norman F.
Published: April 2011

Telenomus phymatae n. sp. is described from the New World (Canada, USA, Colombia /S.A./), reared from the eggs of Phymata sp. (Heteroptera: Phymatidae).
EFFECT OF FOREST SPRAYING WITH ACEPHATE INSECTICIDE ON CONSUMPTION OF SPIDERS BY BROOK TROUT (SALVELINUS FONTINALIS)
Authors: Hydorn Susan B. , Rabeni Charles F. , Jennings Daniel T.
Published: April 2011

Stomachs of mature brook trout, Salvelinus fontinalis Mitch., from sprayed and unsprayed streams were analyzed for arthropods. Within 48 h after exposure to aerial applications of 560 g/ha acephate (Orthene®) against spruce budworm, Choristoneura fumiferana (Clem.), fish consumed many more spiders and other arthropods. Caged spiders in an acephate-sprayed forest behaved abnormally and had low survival.
CHALCID PARASITOID ATTACK ON A GALL WASP POPULATION (ACRASPIS HIRTA (HYMENOPTERA: CYNIPIDAE)) ON QUERCUS PRINUS (FAGACEAE)
Authors: Washburn Jan O. , Cornell Howard V.
Published: April 2011

The developmental sequence of the asexual generation of the gall wasp Acraspis hirta Bassett (Hymenoptera: Cynipidae) on its host plant Quercus prinus (Fagaceae) is described from a site in New Jersey. Chalcid attack was the key mortality factor in the gall population. Parasitoids concentrated their attack on host galls before galls matured and hardened. Hardening of gall walls appears to be the most important deterrent to later attack by inhibiting oviposition. Parasitoids which emerged from A. hirta galls did not reinfest the surviving hosts but probably shifted to other gall species. The parasitoids of Cynips divisa, a similar Old World gall species, became progressively more generalized in their feeding preferences as the season progressed. No such temporal sequencing wau observed in A. hirta.

Spacing out of A. hirta galls among leaves is an important strategy for increasing individual fitness in response to parasitoid attack. Most trees were sparsely infested, and few leaves supported more than one gall. Parasitoid mortality was significantly higher on multiply infected leaves than on leaves with one gall. Galls which were parasitized had a significantly smaller average distance to the nearest neighboring gall than those that escaped parasitism suggesting a slight resource concentration effect.
NOTES ON SOME NEW WORLD AND PALEARCTIC SPECIES FORMERLY IN ATHOUS ESCHSCHOLTZ AND HARMINIUS FAIRMAIRE WITH NEW SYNONYMIES (COLEOPTERA: ELATERIDAE)
Authors: Becker Edward C.
Published: April 2011

The Nearctic species, as well as several Palearctic species, of Athous Eschscholtz, Harminius Fairmaire, Hemicrepidius Germar, and Acanthathous Champion are studied and rearranged with the following new combinations: the Nearctic Hemicrepidius simplex (LeConte), H. falli (Reitter), and H. palpalis (Fall) (each from Athous); the Palearctic Hemicrepidius hirtus (Herbst) and H. niger (Linnaeus) (each from Athous); Hemicrepidius dauricus (Mannerheim) and H. flavipennis (Cherepanov) (each from Harminius); Hemicrepidius inornatus (Lewis) (from Yukara); and Acanthathous photinoides (Champion), A. campanulatus (Champion), A. mexicanus (Candèze), A. aequinoctialis (Champion), A. marcidus (Champion), A. aztecus (Champion), A. rugipennis (Champion), A. angusticollis (Champion), A. carinicollis (Champion), and A. championi (Schwarz) (each from Athous). Hemicrepidius hirtus (Candèze) (nee hirtus Herbst) is renamed californicus, new name, and the name H. hemipodus (Say) is recognized rather than decoloratus (Say). Pertinent generic characters are illustrated and brief notes are given for each of the above species (except those in Acanthathous) and for Harminius (Diacanthous) triundulatus (Mannerheim), H. (D.) undulatus (DeGeer), and Hemicrepidius pallidipennis (Mannerheim). Renter’s two subgenera of Harminius: Diacanthous and Megathous are recognized. A key to the genera associated with Athous and to the subgenera of Harminius is provided.
PYRRHALTA VIBURNI (COLEOPTERA: CHRYSOMELIDAE), A EURASIAN PEST OF VIBURNUM RECENTLY ESTABLISHED IN CANADA
Authors: Becker Edward C.
Published: April 2011

Pyrrhalta viburni (Paykull), a native of Eurasia, is reported for the first time as established in North America. In the Ottawa, Ont., area (including Hull, Que.) adults were very abundant and causing considerable damage to cultivated varieties of Viburnum opulus L. and moderate damage to the native V. Rafinesquianum Schultes. Photographs, a comparison with the similar species, P. luteola (Müller), and a brief note on egg laying are given.
DESCRIPTIONS OF NEW SPECIES OF TRISETACUS (PROSTIGMATA: ERIOPHYOIDEA) FROM PINACEAE IN EASTERN NORTH AMERICA
Authors: Smith Ian M.
Published: April 2011

Adults of two new species of Trisetacus are described, T. strobi from foliage of Eastern White Pine and T. laricinae from buds of Tamarack.
A REVIEW OF THE LIFE HISTORY, POPULATION LEVELS, AND SPREAD OF THE ANTLER MOTH, CERAPTERYX GRAMINIS (LEPIDOPTERA: NOCTUIDAE), IN NEWFOUNDLAND
Authors: Morris Ray F.
Published: April 2011

The antler moth, Cerapteryx graminis (L.), first discovered in Newfoundland in 1966, has now successfully established itself over an area of approximately 60 km in the greater St. John’s area and surrounding localities. It has become a pest of limited economic importance in hay and pasture fields, and lawns. Black light traps, operated at Mt. Pearl and Kilbride during 1966–1978, were used to monitor population build-up. Notes on the life history of the antler moth in Newfoundland, with some comparisons with that in Great Britain and Europe, are provided. Natural controls are also discussed.
A NEW GENUS BROOKSELLA, NEAR ILNACORA REUTER, WITH NEW SYNONYMY AND NEW COMBINATIONS FOR 15 SPECIES CURRENTLY PLACED IN MELANOTRICHUS REUTER (HETEROPTERA: MIRIDAE)
Authors: Kelton Leonard A.
Published: April 2011

Brooksella n. gen. is described (type-species, Asciodema inconspicua Uhler). Lectotypes are designated for Asciodema inconspicua Uhler and Orthotylus viridicatus Uhler. The following North American species currently in Melanotrichus Reuter are transferred to Brooksella: Asciodema inconspicua Uhler (= M. atricornis Knight, n. syn.), M. chelifer Knight (= M. brevirostris Knight, M. custeri Knight, n. syn.), M. azteci Knight, M. incurvus Knight, M. malvastri Knight, M. nevadensis Knight, M. nicholi Knight, M. shoshonea Knight, Orthotylus althaeae Hussey, O. ferox Van Duzee, O. tibialis Van Duzee, and O. viridicatus Uhler. Male genitalia and tergal process are illustrated for each species and a key to separate them is provided.
PANDEMIS HEPARANA (LEPIDOPTERA: TORTRICIDAE), A TORTRICID NEW TO NORTH AMERICA, ESTABLISHED IN BRITISH COLUMBIA
Authors: Doǧanlar Miktat , Beirne Bryan P.
Published: April 2011

Pandemis heparana Den. and Schiff. is common throughout most of Europe and the Middle East to Siberia, China, Korea, and Japan. It feeds on a wide variety of deciduous trees and shrubs. It is regarded as a minor fruit tree pest in some areas as it can damage flowers and fruit.

Three males and four females from a larger number reared from 87 larvae collected in the Lower Fraser Valley, British Columbia, were identified as of this species by Dr. A. Mutuura, Biosystematics Research Institute, Agriculture Canada, Ottawa. It apparently has not been recorded previously from North America.
SUSCEPTIBILITY OF FIVE SPECIES OF SASKATCHEWAN GRASSHOPPERS TO FIELD APPLICATIONS OF NOSEMA LOCUSTAE (MICROSPORIDA)
Authors: Ewen Al B. , Mukerji M.K.
Published: April 2011

The potential usefulness of Nosema locustae Canning as a microbial agent for grasshopper control was first demonstrated by Henry (1971) and Henry et al. (1973). These authors found that a 50–60% reduction in grasshopper density (as compared with untreated populations) could be achieved, and they speculated that 35–50% of the survivors would be sufficiently infected so that their fecundity would be reduced. The value of incorporating such an agent into a grasshopper pest-management system is obvious: By suppressing high insect densities to manageable levels, the need for conventional chemical insecticides could be reduced and perhaps even restricted only to “hot spot” areas. The objectives of the study we report here were to: (1) Determine if N. locustae was infective to the predominant species of grasshoppers in Saskatchewan; (2) if so, monitor the development of the disease within the populations; and (3) determine if the pathogen could survive over the winter and infect next year's populations. Because this was a preliminary experiment, we did not attempt to determine any effect the pathogen might have on population reduction.