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Abstract On four occasions, the golden dorado (Salminus brasiliensis) was recorded following the green anaconda (Eunectes murinus) in a clearwater river of Midwest Brazil. These observations were considered as an indirect evidence of a following association known as "nuclear-follower feeding association", a condition in which the follower approach the nuclear when it somehow disturbs the substrate and form sediment clouds while foraging, taking the opportunity to feed during this situation. However, no direct observations of golden dorados getting some benefit from the activity of the green anacondas to feed were made. Nevertheless, as there is a varied list of vertebrates considered as nuclear species in the clearwater rivers of Midwest Brazil, it is to be expected that future observations may provide unusual information about nuclear-follower feeding association between fish and snakes in the Neotropics.

Resumo Em quatro ocasiões, o dourado (Salminus brasiliensis) foi registrado seguindo a sucuri-verde (Eunectes murinus) em um rio de águas claras do Centro-Oeste do Brasil. Essas interações foram consideradas como uma evidência indireta de uma associação de seguidor conhecida como "associação de alimentação nuclear-seguidor", uma condição na qual o seguidor se aproxima da espécie nuclear quando esta de alguma forma perturba o substrato e/ou forma nuvens de sedimentos enquanto forrageia, aproveitando a oportunidade para se alimentar durante essa situação. No entanto, observações diretas de dourados obtendo algum benefício da atividade das sucuris para se alimentar não foram feitas. No entanto, como há uma lista variada de vertebrados considerados como espécies nucleares nos rios de águas claras do Centro-Oeste do Brasil, é de se esperar que observações futuras possam fornecer informações incomuns sobre associações do tipo "nuclear-seguidor" entre peixes e serpentes na região Neotropical.

RESUMO

Many authors report biological differences among insecticide-resistant pest species, mainly associated with parameters of life history, but only a few studies approach differences at the behavioural level. Feeding behaviour in Blattella germanica (L.) is modulated by the detection of chemical volatiles emitted from food sources in order to be located a long-median distance, and also by the physicochemical properties of food. This work aimed to study the differences in the feeding behaviour of a susceptible and a pyrethroid-resistant strain of B. germanica, in the location and exploitation of a food source. Resistant males showed a lower performance in the feeding behaviour compared to susceptible males. Particularly, the time taken to locate the source was significantly higher in the resistant individuals, suggesting a lower capacity in the detection of food odours. In addition, although the Intake rate was negatively related to the stiffness of food for both strains, resistant individuals showed a lower intake rate compared to susceptible ones, when exploiting a food source of the same stiffness. In a control context, the phenotypic characteristics associated to feeding of pyrethroid-resistant individuals could induce a behavioural resistance mechanism caused by a reduction in the amount of toxic gel bait ingested. If that is the case, resistance of this strain would not be associated to physiological changes affecting the toxicity of the active principle of gel baits, but to a lower efficacy of these products against resistant individuals due to less amount of gel consumed, generating control problems of this pest.

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In the present study we analysed spatial learning in Vespula germanica wasps when dealing with a walking Y-maze. We recorded the time taken to leave the maze during two consecutive visits and which of the two short arms was chosen to exit. Two treatments were conducted to evaluate whether wasps learned to leave the Y-maze guided either by spatial or visual cues. In Treatment 1, the colour of both arms remained unchanged between two consecutive visits; and in Treatment 2, the position of the coloured arm was switched after the first trial. Our results demonstrated that the time taken to exit the maze on the second trial was less than half in both treatments and wasps left the maze from the previously chosen arm, irrespective of its colour. This is the first study to demonstrate spatial learning in V. germanica wasps by using a walking Y-maze. Free flying wasps learned to enter the Y-maze on their own volition, walk through it, collect food and find their way out more rapidly after a single foraging experience. The current experimental device is suitable for the evaluation of spatial memory processes and exploratory behaviour in this species.

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Many parasitoid species discriminate already parasitized hosts, thus avoiding larval competition. However, females incur in superparasitism under certain circumstances. Superparasitism is commonly observed in the artificial rearing of the parasitoid Diachasmimorpha longicaudata, yet host discrimination has been previously suggested in this species. Here, we addressed host discrimination in virgin D. longicaudata females in a comprehensive way by means of direct and indirect methods, using Ceratitis capitata and Anastrepha fraterculus which are major fruit fly pests in South America. Direct methods relied on the description of the foraging behaviour of females in arenas with parasitized and non-parasitized host larvae. In the indirect methods, healthy larvae were offered to single females and the egg distributions were compared to a random distribution. We found that D. longicaudata was able to recognize parasitized host from both host species, taking 24 h since a first parasitization for A. fraterculus and 48 h for C. capitata. Indirect methods showed females with different behaviours for both host species: complete discrimination, non-random (with superparasitism), and random distributions. A larger percentage of females reared and tested on A. fraterculus incurred in superparasitism, probably associated with higher fecundity. In sum, we found strong evidence of host discrimination in D. longicaudata, detecting behavioural variability associated with the host species, the time since the first parasitization and the fecundity of the females.

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Analyses of resource presentation, floral morphology and pollinator behaviour are essential for understanding specialised plant-pollinator systems. We investigated whether foraging by individual bee pollinators fits the floral morphology and functioning of Blumenbachia insignis, whose flowers are characterised by a nectar scale-staminode complex and pollen release by thigmonastic stamen movements. We described pollen and nectar presentation, analysed the breeding system and the foraging strategy of bee pollinators. We determined the nectar production pattern and documented variations in the longevity of floral phases and stigmatic pollen loads of pollinator-visited and unvisited flowers. Bicolletes indigoticus (Colletidae) was the sole pollinator with females revisiting flowers in staminate and pistillate phases at short intervals, guaranteeing cross-pollen flow. Nectar stored in the nectar scale-staminode complex had a high sugar concentration and was produced continuously in minute amounts (~0.09 µl·h-1 ). Pushing the scales outward, bees took up nectar, triggering stamen movements and accelerating pollen presentation. Experimental simulation of this nectar uptake increased the number of moved stamens per hour by a factor of four. Flowers visited by pollinators received six-fold more pollen on the stigma than unvisited flowers, had shortened staminate and pistillate phases and increased fruit and seed set. Flower handling and foraging by Bicolletes indigoticus were consonant with the complex flower morphology and functioning of Blumenbachia insignis. Continuous nectar production in minute quantities but at high sugar concentration influences the pollen foraging of the bees. Partitioning of resources lead to absolute flower fidelity and stereotyped foraging behaviour by the sole effective oligolectic bee pollinator.

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Abstract: A new foraging tactic for the pearl cichlid, Geophagus brasiliensis, is described from underwater observations performed in a coastal stream of the Atlantic Forest, Southeastern Brazil. Named "shift picking", the foraging tactic involved the manoeuvering of leaves, wood twigs and tree bark present in the substrate, with fish using its mouth to turn objects and uncover macroinvertebrates adhered to the underside of the object being picked ("B-side"). The object-shifting behaviour is rarely reported for fish and the present description seems to be the first record for a freshwater species of South America.

Resumo: Uma nova tática de forrageamento do acará, Geophagus brasiliensis, é descrita a partir de observações subaquáticas realizadas em um riacho costeiro da Mata Atlântica, Sudeste do Brasil. Chamada de "virar para pegar", a tática de forrageamento envolve o movimento de folhas, galhos e cascas de árvores presentes no substrato, com os peixes usando a boca para virar objetos e expor macroinvertebrados aderidos à parte de baixo dos objetos explorados ("lado B"). O comportamento de mover objetos é raramente relatado e o presente trabalho parece ser o primeiro registro para uma espécie de água doce da América do Sul.

RESUMO

During 1442 h of visual observations over 7 years throughout the World Heritage listed Paranaguá estuarine complex, Brazil, seven occurrences of interactions were observed at a single location involving breaching Manta birostris displacing schools of teleosts, which were subsequently preyed upon by Sotalia guianensis. Although the interactions were not definitively categorized as being amensal, commensal or mutual, their restriction to isolated space (adjacent to a protected area) and time (summer) supports previous assertions the area is important to regional productivity and the continuation of protected-area status.

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Melipona colimana Ayala is an endemic species inhabiting temperate forests of pine and oak of south of Jalisco in Mexico. During a year, it was recorded every 15 days foraging activity, environmental parameters and the development of colonies of M. colimana in its wild habitat. For five minutes every hour from 7:00 to 21:00, the bees that entered and left the hive and bringing pollen and resin were registered. Every hour the relative humidity, temperature, wind speed and light intensity was recorded and related to foraging activity. Additionally, the weight of the colonies recently transferred to wooden boxes, the number of brood combs, honey pots and pollen were registered. The time of beginning and ending of the foraging activity differs from the reports of stingless bees of tropical weather and the same happens with the pollen collection. The environmental parameters that affect other tropical stingless bees in the foraging activity also affect M. colimana in temperate climate. It was determined that the major activity season and the presence of more pollen pots in the colony is from November through February, for what it could be the best time of the year for the division and obtainance of new colonies, while the critical period of minor activity and pollen flow was during rainy season. These data may be useful for the future sustainable use of this species in temperate climate.(AU)

Melipona colimana Ayala é uma espécie endémica de clima temperado que habita nas florestas de pinho e de azinheira do sul de Jalisco, no México. Registrou-se durante um ano, todos os quinze dias, a atividade de forragem, os parâmetros ambientais e o desenvolvimento de colônias de M. colimana no seu habitat silvestre. Registrou-se durante cinco minutos, cada hora das 7:00 às 21:00, as abelhas que entraram e saíram da colmeia e as que traziam pólen e resinas. Registrou-se toda hora, a humidade relativa, temperatura, velocidade do vento e intensidade da luz e relacionaram-se à atividade de forragem. Além do mais, registrou-se o peso de colônias recém transferidas a gavetas de madeira e contabilizou-se o número de panais, potes de mel e pólen. A hora de início e de fim da atividade de forragem difere com os reportes das abelhas sem ferrão de clima tropical e o mesmo acontece com a recolecção de pólen. Os parâmetros ambientais que afetam outros meliponinos de clima tropical na forragem também afetam a M. colimana em clima temperado. Determinou-se que a temporada de maior atividade e a presença de mais potes de pólen na colônia é de Novembro a Fevereiro, razão pela qual pode ser a melhor temporada do ano para a divisão e obtenção de novas colônias, enquanto que o período crítico de menor atividade e fluxo de pólen foi durante a temporada de chuvas. Esses dados podem ser úteis para o futuro aproveitamento sustentável de esta espécie em clima temperado.(AU)

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RESUMO

Abstract Melipona colimana Ayala is an endemic species inhabiting temperate forests of pine and oak of south of Jalisco in Mexico. During a year, it was recorded every 15 days foraging activity, environmental parameters and the development of colonies of M. colimana in its wild habitat. For five minutes every hour from 7:00 to 21:00, the bees that entered and left the hive and bringing pollen and resin were registered. Every hour the relative humidity, temperature, wind speed and light intensity was recorded and related to foraging activity. Additionally, the weight of the colonies recently transferred to wooden boxes, the number of brood combs, honey pots and pollen were registered. The time of beginning and ending of the foraging activity differs from the reports of stingless bees of tropical weather and the same happens with the pollen collection. The environmental parameters that affect other tropical stingless bees in the foraging activity also affect M. colimana in temperate climate. It was determined that the major activity season and the presence of more pollen pots in the colony is from November through February, for what it could be the best time of the year for the division and obtainance of new colonies, while the critical period of minor activity and pollen flow was during rainy season. These data may be useful for the future sustainable use of this species in temperate climate.

Resumo Melipona colimana Ayala é uma espécie endémica de clima temperado que habita nas florestas de pinho e de azinheira do sul de Jalisco, no México. Registrou-se durante um ano, todos os quinze dias, a atividade de forragem, os parâmetros ambientais e o desenvolvimento de colônias de M. colimana no seu habitat silvestre. Registrou-se durante cinco minutos, cada hora das 7:00 às 21:00, as abelhas que entraram e saíram da colmeia e as que traziam pólen e resinas. Registrou-se toda hora, a humidade relativa, temperatura, velocidade do vento e intensidade da luz e relacionaram-se à atividade de forragem. Além do mais, registrou-se o peso de colônias recém transferidas a gavetas de madeira e contabilizou-se o número de panais, potes de mel e pólen. A hora de início e de fim da atividade de forragem difere com os reportes das abelhas sem ferrão de clima tropical e o mesmo acontece com a recolecção de pólen. Os parâmetros ambientais que afetam outros meliponinos de clima tropical na forragem também afetam a M. colimana em clima temperado. Determinou-se que a temporada de maior atividade e a presença de mais potes de pólen na colônia é de Novembro a Fevereiro, razão pela qual pode ser a melhor temporada do ano para a divisão e obtenção de novas colônias, enquanto que o período crítico de menor atividade e fluxo de pólen foi durante a temporada de chuvas. Esses dados podem ser úteis para o futuro aproveitamento sustentável de esta espécie em clima temperado.

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The optimal use of available host by parasitoid insects should be favoured by natural selection. For solitary parasitoids, superparasitism (i.e. the egg-laying of several eggs/host) may represent a detrimental phenomenon both in a biological and an applied sense, but under certain circumstances it may be adaptive. Here, we studied the effects of increasing levels of superparasitism (LSPs, number of parasitoid larvae/host) on fitness-related parameters of the immature and adult stages of Diachasmimorpha longicaudata, a solitary endoparasitoid parasitizing Ceratitis capitata. We investigated the moment when supernumerary parasitoid larvae are eliminated and the effects produced by this process, together with its repercussion on female fecundity, parasitism rate, sex ratio, adult survival, flight ability and body size. Complete elimination of competitors occurred soon after larval hatching, before reaching the second larval stage. Elimination process took longer at higher LSPs, although a normal developmental (egg-adult) time was achieved. For LSPs 1, 2, 3 and 5 the effects on parasitoid emergence were mild, but LSP 10 led to the death of all developing parasitoids. Aside from this, to develop in superparasitized hosts did not significantly affect any of the evaluated parameters, and only a female-biased sex ratio was observed at higher LSPs. However, the effects of superparasitism on the adults may have a different outcome under more variable conditions in the field, once they are released for biological control purposes.

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The hunting tactics of lemon sharks, Negaprion brevirostris, are described from underwater and cliff-top observations in the Fernando de Noronha Archipelago, western equatorial Atlantic, Brazil. Two main tactics were observed in the shallow waters of sandy beaches and reefs environments: (i) “substrate inspection” of crevices and holes over rocky and reef bottoms, and (ii) “sardine blitz”, which refer to striking schools of fishes (mainly sardines) in the surf zone. The first tactic was restricted to juveniles up to 2 m of total length, whereas subadult and adult sharks with total length larger than 2 m displayed the second. As lemon sharks use waters less than 5 m depth to hunt, perform social behaviours and predator avoidance, results highlight the importance of properly managing these habitats for their conservation, especially in areas where tourism has increased substantially.(AU)

As táticas de caça do tubarão-limão, Negaprion brevirostris, são descritas a partir de observações subaquáticas e de mirantes no Arquipélago de Fernando de Noronha, no Atlântico ocidental equatorial, Brasil. Duas táticas principais foram observadas em águas rasas de praias arenosas e ambientes recifais: (i) “inspeção do substrato” de fendas e cavidades em fundos recifais e rochosos e (ii) “ataques a sardinhas”, que se referem a ataques repentinos a cardumes de peixes (principalmente sardinhas) na zona de arrebentação. A primeira tática esteve restrita a tubarões jovens com até 2 m de comprimento total, enquanto a segunda foi executada por subadultos e adultos com comprimento total acima de 2 m. Como os tubarões-limão utilizam águas com profundidades inferiores a 5 m para caçar, realizar interações sociais e evitar predadores, os resultados realçam a importância de se manejar adequadamente estes hábitats para sua conservação, especialmente em áreas onde o turismo tem aumentado substancialmente.(AU)

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RESUMO

The hunting tactics of lemon sharks, Negaprion brevirostris, are described from underwater and cliff-top observations in the Fernando de Noronha Archipelago, western equatorial Atlantic, Brazil. Two main tactics were observed in the shallow waters of sandy beaches and reefs environments: (i) “substrate inspection” of crevices and holes over rocky and reef bottoms, and (ii) “sardine blitz”, which refer to striking schools of fishes (mainly sardines) in the surf zone. The first tactic was restricted to juveniles up to 2 m of total length, whereas subadult and adult sharks with total length larger than 2 m displayed the second. As lemon sharks use waters less than 5 m depth to hunt, perform social behaviours and predator avoidance, results highlight the importance of properly managing these habitats for their conservation, especially in areas where tourism has increased substantially.(AU)

As táticas de caça do tubarão-limão, Negaprion brevirostris, são descritas a partir de observações subaquáticas e de mirantes no Arquipélago de Fernando de Noronha, no Atlântico ocidental equatorial, Brasil. Duas táticas principais foram observadas em águas rasas de praias arenosas e ambientes recifais: (i) “inspeção do substrato” de fendas e cavidades em fundos recifais e rochosos e (ii) “ataques a sardinhas”, que se referem a ataques repentinos a cardumes de peixes (principalmente sardinhas) na zona de arrebentação. A primeira tática esteve restrita a tubarões jovens com até 2 m de comprimento total, enquanto a segunda foi executada por subadultos e adultos com comprimento total acima de 2 m. Como os tubarões-limão utilizam águas com profundidades inferiores a 5 m para caçar, realizar interações sociais e evitar predadores, os resultados realçam a importância de se manejar adequadamente estes hábitats para sua conservação, especialmente em áreas onde o turismo tem aumentado substancialmente.(AU)

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Understanding how predators select their prey can provide important insights into community structure and dynamics. However, the suite of prey species available to a predator is often spatially and temporally variable. As a result, species-specific selectivity data are of limited use for predicting novel predator-prey interactions because they are assemblage specific. We present a method for predicting diet selection that is applicable across prey assemblages, based on identifying general morphological and behavioural traits of prey that confer vulnerability to predation independent of species identity. We apply this trait-based approach to examining prey selection by Indo-Pacific lionfish (Pterois volitans and Pterois miles), invasive predators that prey upon species-rich reef fish communities and are rapidly spreading across the western Atlantic. We first generate hypotheses about morphological and behavioural traits recurring across fish species that could facilitate or deter predation by lionfish. Constructing generalized linear mixed-effects models that account for relatedness among prey taxa, we test whether these traits predict patterns of diet selection by lionfish within two independent data sets collected at different spatial scales: (i) in situ visual observations of prey consumption and availability for individual lionfish and (ii) comparisons of prey abundance in lionfish stomach contents to availability on invaded reefs at large. Both analyses reveal that a number of traits predicted to affect vulnerability to predation, including body size, body shape, position in the water column and aggregation behaviour, are important determinants of diet selection by lionfish. Small, shallow-bodied, solitary fishes found resting on or just above reefs are the most vulnerable. Fishes that exhibit parasite cleaning behaviour experience a significantly lower risk of predation than non-cleaning fishes, and fishes that are nocturnally active are at significantly greater risk. Together, vulnerable traits heighten the risk of predation by a factor of nearly 200. Our study reveals that a trait-based approach yields insights into predator-prey interactions that are robust across prey assemblages. Importantly, in situ observations of selection yield similar results to broadscale comparisons of prey use and availability, which are more typically gathered for predator species. A trait-based approach could therefore be of use across predator species and ecosystems to predict the outcomes of changing predator-prey interactions on community dynamics.

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In this study we tested for density-dependent relationships between visitation rates of the Scale-throated Hermit (Phaethornis eurynome) and the plant density and flower number of the bromeliad Vriesea incurvata, by comparing plots with varying densities of this bromeliad. Eight 100 m2 plots were established at least 200 m from each other; four plots contained 10-15 individuals of V. incurvata each, whereas the other four contained 4-5 individuals each. The visitors, number of visits, behaviour (nectar thief or potential pollinator) and the height of foraging were recorded during focal observations on the plants. The number of visits of P. eurynome varied according to the local density of V. incurvata, showing that the heterogeneous distribution of this bromeliad species may promote adjustments in the pollinator populations, through resource variation at a local scale.

Neste estudo foram testadas as relações entre taxas de visitação de Phaethornis eurynome e a densidade e o número de flores de Vriesea incurvata, comparando-se parcelas com diferentes densidades desta bromélia. Oito parcelas de 100 m2 foram estabelecidas a pelo menos 200 m uma da outra; quatro parcelas continham de 10 a 15 indivíduos de V. incurvata cada, enquanto as outras quatro continham de 4 a 5 indivíduos cada. Os visitantes, o número de visitas, o comportamento (pilhador ou potencial polinizador) e altura de forrageamento foram registrados em observações focais das plantas. O número de visitas por P. eurynome variou conforme a densidade de V. incurvata na área, demonstrando que a distribuição heterogênea desta bromélia pode promover ajustes populacionais por parte dos polinizadores, através da variação da oferta de recursos em uma escala local.

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In this study we tested for density-dependent relationships between visitation rates of the Scale-throated Hermit (Phaethornis eurynome) and the plant density and flower number of the bromeliad Vriesea incurvata, by comparing plots with varying densities of this bromeliad. Eight 100 m2 plots were established at least 200 m from each other; four plots contained 10-15 individuals of V. incurvata each, whereas the other four contained 4-5 individuals each. The visitors, number of visits, behaviour (nectar thief or potential pollinator) and the height of foraging were recorded during focal observations on the plants. The number of visits of P. eurynome varied according to the local density of V. incurvata, showing that the heterogeneous distribution of this bromeliad species may promote adjustments in the pollinator populations, through resource variation at a local scale.(AU)

Neste estudo foram testadas as relações entre taxas de visitação de Phaethornis eurynome e a densidade e o número de flores de Vriesea incurvata, comparando-se parcelas com diferentes densidades desta bromélia. Oito parcelas de 100 m2 foram estabelecidas a pelo menos 200 m uma da outra; quatro parcelas continham de 10 a 15 indivíduos de V. incurvata cada, enquanto as outras quatro continham de 4 a 5 indivíduos cada. Os visitantes, o número de visitas, o comportamento (pilhador ou potencial polinizador) e altura de forrageamento foram registrados em observações focais das plantas. O número de visitas por P. eurynome variou conforme a densidade de V. incurvata na área, demonstrando que a distribuição heterogênea desta bromélia pode promover ajustes populacionais por parte dos polinizadores, através da variação da oferta de recursos em uma escala local.(AU)

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Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the foraging behaviour (including walking activity and speed) of T. atopovirilia is reported in this paper. Temperature strongly affected T. atopovirilia female walking activity, but Wolbachia infected and uninfected females differed in none of the behavioural components that were measured such as walking activity and walking speed. Walking activity was highest at 25 ºC and differed significantly from that at 20 and 15 ºC. Trichogramma wasps were highly affected at 15 ºC. Behaviour analysis with females showed that female wasps spend most of the time on drilling + ovipositing on host eggs followed by host drumming and walking while drumming. The parasitism rate and number of offspring did not differ significantly between infected and cured Trichogramma females. Biological control implications of these findings are discussed.

Formas unissexuais de Trichogramma têm despertado a atenção de pesquisadores devido as potenciais vantagens deste parasitóide como agente de controle biológico. O estudo do "Fitness" tem sido avaliado e entender o custo de ser infectado por Wolbachia ajudará em determinar se formas infectadas por Wolbachia (unisexuais) são realmente melhores que as sexuadas quando utilizadas em programas de controle biológico. A influência de Wolbachia no comportamento de procura (incluindo a atividade e a velocidade de caminhamento) de T. atopovirilia é relatada neste artigo. A temperatura afetou grandemente a atividade de caminhamento de fêmeas de T. atopovirilia, entretanto os componentes de comportamento tais como a atividade e a velocidade de caminhamento não diferiram em relação às fêmeas infectadas e não infectadas. A atividade de caminhamento foi maior a 25 ºC e diferiu significativamente de 20 e 15 ºC. Fêmeas de Trichogramma foram altamente afetados a 15 ºC. Em função da análise do comportamento com fêmeas, pode-se verificar que houve maior tempo gasto no processo de oviposição, seguido pelo toque com as antenas sobre os ovos dos hospedeiros e do caminhamento ao mesmo tempo que toca os ovos com as antenas. A taxa de parasitismo e o número de descendentes não diferiram significativamente entre fêmeas de Trichogramma infectadas e curadas da infecção por Wolbachia. As implicações dos resultados obtidos sobre o controle biológico são discutidas.

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Habitat use by the Little Blue Heron (Egretta caerulea) and discovery of feeding territoriality are discussed here. The results showed the existence of a territorial individual defending an area (2,564.46 ± 943.56 m²) close to the mangrove, and non-territorial individuals (9.17 ± 2.54) in the rest of a demarcated area (mean area for the non-territorial: 893.25 ± 676.72). A weak positive correlation (r = 0.47, df = 46, p < 0.05) was found between the overlapping of territorial and non-territorial individuals (2.85 ± 3.07 m²) and the mean overlapped area for territorial individuals (171.41 ± 131.40 m²). Higher capture (1.52 ± 1.14 × 1.00 ± 1.37 catches/minutes) and success rates (0.45 ± 0.31 × 0.21 ± 0.27) and lower energy expenditure rates (45.21 ± 14.96 × 51.22 ± 14.37 steps/minutes; and 3.65 ± 2.55 × 4.94 ± 3.28 stabs/minutes) were observed for individuals foraging in areas close to the mangrove. The results suggest that the observed territorial behaviour is more related to a number of food parameters than to intruder pressure, and also that the observed territoriality might be related to defense of areas with higher prey availability.

Uso do habitat pela garça-azul (Egretta caerulea) e a descoberta da territorialidae alimentar são discutidos aqui. Os resultados apontaram para a existência de um indivíduo territorial defendendo uma área (2.564,46 ± 943,56 m²) próxima ao manguezal e indivíduos não-territoriais (9,17 ± 2,54) no restante de uma área demarcada (média das áreas para os não-territoriais: 893,25 ± 676,72). Uma correlação positiva fraca (r = 0,47, df = 46, p < 0,05) foi encontrada entre a sobreposição de indivíduos territoriais e não-territoriais (2,85 ± 3,07 m²) e a média de área sobreposta para indivíduos territoriais (171,41 ± 131,40 m²). Maiores taxas de captura (1,52 ± 1,14 × 1,00 ± 1,37 capturas/minutos) e sucesso (0,45 ± 0,31 × 0,21 ± 0,27 capturas/tentativas de captura) e menores taxas de gasto energético (45,21 ± 14,96 × 51,22 ± 14,37 passos/min; e 3,65 ± 2,55 × 4,94 ± 3,28 tentativas de captura/min) foram registradas para indivíduos forrageando em áreas mais próximas do manguezal. Os resultados sugerem que o comportamento territorial observado tem mais relação com alguns parâmetros alimentares do que com a pressão de intrusos. Assim como a territorialidade observada pode estar relacionada com a defesa de áreas que contém alta disponibilidade de presas.

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Habitat use by the Little Blue Heron (Egretta caerulea) and discovery of feeding territoriality are discussed here. The results showed the existence of a territorial individual defending an area (2,564.46 ± 943.56 m²) close to the mangrove, and non-territorial individuals (9.17 ± 2.54) in the rest of a demarcated area (mean area for the non-territorial: 893.25 ± 676.72). A weak positive correlation (r = 0.47, df = 46, p < 0.05) was found between the overlapping of territorial and non-territorial individuals (2.85 ± 3.07 m²) and the mean overlapped area for territorial individuals (171.41 ± 131.40 m²). Higher capture (1.52 ± 1.14 × 1.00 ± 1.37 catches/minutes) and success rates (0.45 ± 0.31 × 0.21 ± 0.27) and lower energy expenditure rates (45.21 ± 14.96 × 51.22 ± 14.37 steps/minutes; and 3.65 ± 2.55 × 4.94 ± 3.28 stabs/minutes) were observed for individuals foraging in areas close to the mangrove. The results suggest that the observed territorial behaviour is more related to a number of food parameters than to intruder pressure, and also that the observed territoriality might be related to defense of areas with higher prey availability.(AU)

Uso do habitat pela garça-azul (Egretta caerulea) e a descoberta da territorialidae alimentar são discutidos aqui. Os resultados apontaram para a existência de um indivíduo territorial defendendo uma área (2.564,46 ± 943,56 m²) próxima ao manguezal e indivíduos não-territoriais (9,17 ± 2,54) no restante de uma área demarcada (média das áreas para os não-territoriais: 893,25 ± 676,72). Uma correlação positiva fraca (r = 0,47, df = 46, p < 0,05) foi encontrada entre a sobreposição de indivíduos territoriais e não-territoriais (2,85 ± 3,07 m²) e a média de área sobreposta para indivíduos territoriais (171,41 ± 131,40 m²). Maiores taxas de captura (1,52 ± 1,14 × 1,00 ± 1,37 capturas/minutos) e sucesso (0,45 ± 0,31 × 0,21 ± 0,27 capturas/tentativas de captura) e menores taxas de gasto energético (45,21 ± 14,96 × 51,22 ± 14,37 passos/min; e 3,65 ± 2,55 × 4,94 ± 3,28 tentativas de captura/min) foram registradas para indivíduos forrageando em áreas mais próximas do manguezal. Os resultados sugerem que o comportamento territorial observado tem mais relação com alguns parâmetros alimentares do que com a pressão de intrusos. Assim como a territorialidade observada pode estar relacionada com a defesa de áreas que contém alta disponibilidade de presas.(AU)

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Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the foraging behaviour (including walking activity and speed) of T. atopovirilia is reported in this paper. Temperature strongly affected T. atopovirilia female walking activity, but Wolbachia infected and uninfected females differed in none of the behavioural components that were measured such as walking activity and walking speed. Walking activity was highest at 25 ºC and differed significantly from that at 20 and 15 ºC. Trichogramma wasps were highly affected at 15 ºC. Behaviour analysis with females showed that female wasps spend most of the time on drilling + ovipositing on host eggs followed by host drumming and walking while drumming. The parasitism rate and number of offspring did not differ significantly between infected and cured Trichogramma females. Biological control implications of these findings are discussed.(AU)

Formas unissexuais de Trichogramma têm despertado a atenção de pesquisadores devido as potenciais vantagens deste parasitóide como agente de controle biológico. O estudo do "Fitness" tem sido avaliado e entender o custo de ser infectado por Wolbachia ajudará em determinar se formas infectadas por Wolbachia (unisexuais) são realmente melhores que as sexuadas quando utilizadas em programas de controle biológico. A influência de Wolbachia no comportamento de procura (incluindo a atividade e a velocidade de caminhamento) de T. atopovirilia é relatada neste artigo. A temperatura afetou grandemente a atividade de caminhamento de fêmeas de T. atopovirilia, entretanto os componentes de comportamento tais como a atividade e a velocidade de caminhamento não diferiram em relação às fêmeas infectadas e não infectadas. A atividade de caminhamento foi maior a 25 ºC e diferiu significativamente de 20 e 15 ºC. Fêmeas de Trichogramma foram altamente afetados a 15 ºC. Em função da análise do comportamento com fêmeas, pode-se verificar que houve maior tempo gasto no processo de oviposição, seguido pelo toque com as antenas sobre os ovos dos hospedeiros e do caminhamento ao mesmo tempo que toca os ovos com as antenas. A taxa de parasitismo e o número de descendentes não diferiram significativamente entre fêmeas de Trichogramma infectadas e curadas da infecção por Wolbachia. As implicações dos resultados obtidos sobre o controle biológico são discutidas.(AU)

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Several bird species practice anting. While anting a bird holds an ant or other arthropod that produces toxic or irritating secretions and rubs it on the plumage. Here I describe the White-collared Woodcreeper (Xiphocolaptes albicollis) rubbing its body with millipedes of the orders Spirostreptida and Polydesmida while foraging among banana stumps or at bromeliad clumps in southeastern Brazil. On three occasions I recorded the bird holding a millipede in the bill and rubbing it against its chest, belly, and wings. From time to time the millipede was "chewed", and hammered against the substratum and then rubbed on the plumage again. After a while the millipede was ingested or dropped. Bromeliads harbour a rich fauna that includes mosquitoes, ticks, spiders, and snakes, and some of them may be potential hazards to birds that forage among the accumulated plant debris. The toxic secretions of millipedes may act as a deterrent against some of these hazardous animals, and the woodcreeper's behaviour also reduces the noxiousness of a toxic prey before ingestion.

Diversas espécies de aves praticam o formicar, comportamento no qual a ave segura uma formiga ou outro artrópode que produza secreção tóxica ou irritante e a esfrega na plumagem. Descrevo aqui o Arapaçu-de-garganta-branca (Xiphocolaptes albicollis) formicando-se com milípedes das ordens Spirostreptida e Polydesmida durante procura de alimento entre tocos de bananeiras ou em tufos de bromélias, no sudeste do Brasil. Em três ocasiões registrei a ave mantendo no bico um milípede e esfregando-o no peito, na barriga e nas asas. De vez em quando o milípede era mandibulado, golpeado contra o substrato e esfregado na plumagem novamente. Após certo tempo o milípede era ingerido ou descartado. Bromélias abrigam uma fauna rica que inclui mosquitos, carrapatos, aranhas e serpentes, alguns dos quais podem constituir risco para aves que ali forrageiam. A secreção tóxica dos milípedes pode agir como repelente contra alguns destes animais danosos. Adicionalmente, o comportamento do arapaçu reduz o grau de toxidez da presa antes da sua ingestão.

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