宽索鳃金龟的研究

宽索鳃金龟是为言猕猴挑的重要食叶害虫．该虫在福建建宁县一年发生一代,以成虫在土中越冬,翌年4月上旬开始出土为害,4月下旬至5月下旬为害盛期,成虫可整夜取食猕猴桃叶片和花器,成虫出土及人土的时间较为整齐．5月上旬雌虫开始在土中产卵,5月下旬开始孵化．幼虫3龄,在土中1-20cm处活动,以8-10cm处占绝大多数,幼虫取食土壤中腐植质和根皮,截根．9月上旬开始化蛹,10月中旬成虫开始羽化。但当年不出土,逗留在土中。并越冬．采用50％辛硫磷1000—2000倍液防治幼虫：80％敌敌畏乳油1000倍．帅％乐果800-1000倍、25％溴氰菊酯5000倍等药液毒杀成虫均有良好效果,亦可人工捕杀和灯光诱杀成虫．     

Attraction to Carbon Dioxide from Feeding Resources and Conspecific Neighbours in Larvae of the Rhinoceros Beetle Trypoxylus dichotomus

Saprophagous (feeding on decaying matter) insects often use carbon dioxide (CO₂) as a cue for finding food. Humus-feeding larvae of the giant rhinoceros beetle Trypoxylus dichotomus exhibit a clumped distribution in natural microhabitats, but the mechanisms driving the distribution were unknown. Herein, I examined whether larvae use CO₂ as a cue for fermented humus and aggregate in the vicinity of the food. I found that (i) larvae of T. dichotomus are strongly attracted to CO₂, (ii) larvae orient toward highly fermented humus when given a choice between highly and poorly fermented humus, (iii) the highly fermented humus emits more CO₂ than the poorly fermented humus, and (iv) larvae grow larger when fed highly fermented humus rather than poorly fermented humus. The clumped distribution of larvae is probably formed along the concentration gradient of CO₂ induced by heterogeneity of fermented organic materials in soil. My laboratory experiments also revealed that larvae are chemically attracted to each other. Moreover, CO₂ concentrations in soil were increased by the larval respiration, and small amounts of CO₂ (much less than emitted during respiration by a single larva) were sufficient for larval attraction. These results suggest that not only response to fermented food resources, but also respiratory CO₂ from conspecifics may lead to aggregation. Enhanced densities resulted in reduced weight gain under experimental conditions. However, exploiting a high-value resource at enhanced densities still led to greater body weight compared to individually exploiting a low-value resource. This demonstrates the adaptive value of the response to CO₂ sources in this species.     

Nest losses of cavity nesting birds caused by dormice (Gliridae, Rodentia)

Mammals are common predators on bird nests. However, their species identity frequently remains unknown. Here we present long-term data (1975–2005) from a central European woodland on the predatory effect of three dormice species (Rodentia, Gliridae) on cavity-nesting birds. Dormice are mostly frugivorous during the active late-summer season, but shortly after they terminate hibernation, they frequently depredate cavity-nesting-bird nests. The seven bird species studied, lost on average between 2.9 to 18.4% of their broods. MigratoryFicedula flycatchers suffered the highest brood losses, while the residentParus titmice and the nuthatchSitta europaea had much lower brood losses. The three dormice species differed significantly in their predatory effect during different avian breeding stages. The edible dormouseGlis glis (Linnaeus, 1766) depredated both eggs and nestlings equally, while the common dormouseMuscardinus avellanarius (Linnaeus, 1758) and the forest dormouseDryomys nitedula (Pallas, 1778) destroyed more nests during egg laying and the incubation period. Among adult birds, females were taken more frequently by dormice than males. Among avian species, adultFicedula flycatchers were more often depredated than the titmice and nuthatch. Our study provided further evidence, that among the traditional studies on the costs of reproduction, parental mortality at the nests needs to be considered and that incubating or brooding females might be under higher predation risk than the males.     

Arthropods (Pseudoscorpionidea,Acarina, Coleoptera,Siphonaptera) in nests of the bearded tit (<Emphasis Type="Italic">Panurus biarmicus</Emphasis>)

In the period 1993–2006, during investigation of reproduction biology of the bearded tit, 106 deserted nests of the species were collected in Slovakia, Austria and Italy and their arthropod fauna was analyzed. Occasionally introduced individuals of the pseudoscorpion Lamprochernes nodosus, a frequent species in Central Europe, were recorded in the nests. Altogether 984 individuals and 33 species of mesostigmatic mites (Acari) were found in 46.2% of the nests examined. The ectoparasite Ornithonyssus sylviarum was most abundant and frequent; it represented almost 68.3% of all individuals. Due to it, the parasitic mites predominated (69.4% of individuals). Other ecological groups were less represented: edaphic detriticols − 11.6%, coprophils − 10.7%, species of vegetation stratum − 8.2%, and nidicols − 0.2%. Beetles (40 species, 246 individuals) were present in 57 nests. Most of the beetles were strongly hygrophilous species inhabiting soil surface in the reed stands or other types of wetlands and the shore vegetation. Predators represented 59% of all individuals. They might find food in the nests, but none of the species had a close relationship to bird nests and represented 35% of species. All beetle species penetrated the nests occasionally, when ascending on the vegetation or searching cover during periods of increased water level. Occasionally, larvae and nymphs of the Dermacentor marginatus tick were found. They were most probably introduced by insectivores of the genus Neomys. Only one species of fleas, Ceratophyllus garei — a parasite of birds nesting in humid environment, was recorded in the nests.     

Microhabitat selection by two reptile ticks at their parapatric boundary

The parapatric boundary between the reptile ticks. Aponomma hydrosauri and Amblyomma limbatum, near Mt Mary, South Australia, coincides with a vegetational ecotone. Samples of litter from each side of the tick boundary showed considerable heterogeneity, but there were consistent differences in the composition and quantity of litter. North of the boundary, where Amb. limbatum is found, there is less litter and an absence of Eucalyptus leaves in the litter. Since the litter retards evaporative water loss, and Ap. hydrosauri is less tolerant of dehydration, reduced litter quantity may reduce the fitness of colonizing Ap. hydrosauri. In laboratory and field trials, larvae and nymphs of both tick species chose litter microhabitats in preference to bare soil, with the exception of fed Ap. hydrosauri larvae which, in trials with litter from north of the boundary, rarely moved from the bare soil. This behaviour may also reduce the fitness of colonizing Ap. hydrosauri. The two species adopted different positions in the litter. Ap. hydrosauri were predominantly found on the surface, at the interface between soil and litter as fed larvae, and on or under the surface as nymphs. Amb. limbatum larvae were more often buried under the surface, while nymphs were found mostly in the litter above the soil surface. Hypotheses to explain the maintenance of the parapatric boundary are discussed in the light of these results.     

Generalist dung attraction response in a New Zealand dung beetle that evolved with an absence of mammalian herbivores

1. Dung beetles (Scarabaeidae: Scarabaeinae) are integral parts of many ecosystems because of their role in decomposition of dung; particularly mammal dung, which forms the diet of both larvae and adults. 2. New Zealand dung beetles are unusual as they are flightless and evolved on islands with a highly depauperate mammal fauna and thus without the usual dung resource used by dung beetles elsewhere. The diet of New Zealand dung beetles is unknown. 3. We hypothesised (1) that the endemic dung beetle Saphobius edwardsi would be attracted to a broad range of food types, and (2) that S. edwardsi would be able to survive and reproduce on a range of dung types and puriri (Vitex lucens) humus. 4. Laboratory choice tests identified that S. edwardsi was attracted to a range of mammal, bird, invertebrate, and reptile dung types, but not to non‐dung food sources. Five‐month no‐choice tests found that beetle survival rates were lower for beetles fed with humus compared with those fed on mammal, bird, or invertebrate dung. None of the beetles reproduced. 5. This study suggests S. edwardsi have a strong preference for dung, and are likely to be broad dung generalists in their feeding behaviour.     

Artificial diets for the larval oak longicorn beetle, <Emphasis Type="Italic">Moechotypa diphysis</Emphasis> (Coleoptera: Cerambycidae)

The oak longicorn beetle, Moechotypa diphysis (Pascoe), is a pest of bed logs for shiitake mushroom and an invasive species on Japan’s main islands. I attempted to rear larvae of M. diphysis on two artificial diets consisting of a commercially available diet for silkworm plus dried yeast and sawdust of the sawtooth oak, Quercus acutissima Carruthers, or of Japanese beech, Fagus crenata Blume. Newly hatched larvae were inoculated on these artificial diets and reared at 25°C in the dark. More than 60% of larvae emerged as adults when fed with these diets. The weights of emerged adults fed on the artificial diets were heavier than those emerging from logs of Q. acutissima, their natural diet, in a field cage. These results demonstrate that the two artificial diets are useful for rearing M. diphysis larvae and can assist further studies on the development of this invasive species.     

Stage‐dependent responses to emergent habitat heterogeneity: consequences for a predatory insect population in a coffee agroecosystem

Interactions among members of biological communities can create spatial patterns that effectively generate habitat heterogeneity for other members in the community, and this heterogeneity might be crucial for their persistence. For example, stage‐dependent vulnerability of a predatory lady beetle to aggression of the ant, Azteca instabilis, creates two habitat types that are utilized differently by the immature and adult life stages of the beetle. Due to a mutualistic association between A. instabilis and the hemipteran Coccus viridis – which is A. orbigera main prey in the area – only plants around ant nests have high C. viridis populations. Here, we report on a series of surveys at three different scales aimed at detecting how the presence and clustered distribution of ant nests affect the distribution of the different life stages of this predatory lady beetle in a coffee farm in Chiapas, Mexico. Both beetle adults and larvae were more abundant in areas with ant nests, but adults were restricted to the peripheries of highest ant activity and outside the reach of coffee bushes containing the highest densities of lady beetle larvae. The abundance of adult beetles located around trees with ants increased with the size of the ant nest clusters but the relationship is not significant for larvae. Thus, we suggest that A. orbigera undergoes an ontogenetic niche shift, not through shifting prey species, but through stage‐specific vulnerability differences against a competitor that renders areas of abundant prey populations inaccessible for adults but not for larvae. Together with evidence presented elsewhere, this study shows how an important predator is not only dependent on the existence of two qualitatively distinct habitat types, but also on the spatial distribution of these habitats. We suggest that this dependency arises due to the different responses that the predator's life stages have to this emergent spatial pattern.     

Is host plant choice by a clytrine leaf beetle mediated through interactions with the ant Crematogaster lineolata?

In the grasslands of northeastern Kansas, adult populations of Anomoea flavokansiensis, an oligophagous leaf beetle (subfamily Clytrinae), specialize on Illinois bundleflower (Desmanthus illinoensis) even though other reported host species commonly occur and are simultaneously available. We performed choice feeding tests to examine whether A. flavokansiensis adults have a fixed feeding preference for bundleflower. In choice tests, beetles ate similar amounts of bundleflower and honey locust (Gleditsia triacanthos). In addition, we measured fecundity and longevity of adults in no-choice tests to determine if adults were adapted solely to bundleflower. In no-choice tests, fecundity and longevity were no different for adults feeding on bundleflower and honey locust. We next examined the influence of host plant on the attractiveness of beetle eggs to ants. In northeastern Kansas, Crematogaster lineolata ants are attracted to A. flavokansiensis eggs and carry them into their nests where the larvae hatch and apparently reside as inquilines. C. lineolata exhibited a strong preference for eggs from female A. flavokansiensis that fed exclusively on bundleflower compared to eggs from females that fed exclusively on honey locust. Local populations of A. flavokansiensis in northeastern Kansas may specialize on bundleflower to increase the chances of their eggs being transported by C. lineolata ants into their nests. C. lineolata nests may serve as a predator-free and sheltered environment in which A. flavokansiensis eggs undergo embryogenesis. Received: 1 September 1997 / Accepted: 9 February 1998     

Kleptoparasitic behaviour of Aphodius rufipes (L.) larvae in nests of Geotrupes spiniger Marsh. (Coleoptera, Scarabaeidae)

Abstract.

• 1 Third instar larvae of A.rufipes were found in short vertical shafts in the soil beneath horse dung and they entered the underground brood masses of G.spiniger when these occurred beneath the same deposit of dung.
• 2 A.rufipes larvae excavated shafts (60–80mm deep) beneath dung in cages. Just before diapause they burrowed down to the floor of the cage. Burrowing was inhibited in compact soil and in very dry soil. The feeding larvae were attracted to dung and to moisture and they readily attacked other larvae with their mandibles.
• 3 In cages which contained G. spiniger nests the A.rufipes larvae burrowed down to feed on the G.spiniger brood masses. G.spiniger eggs and larvae did not act as attractants but they were often destroyed if the A.rufipes larvae encountered them by chance.
• 4 In cages which contained G.stercorarxus nests A.fossor larvae burrowed down to feed on the brood masses if no dung was provided at the surface.
• 5 This non-obligatory parasitism arises from the normal behaviour of the larvae and is usually of trivial significance, but under certain conditions the protected environment of an underground nest may favour the survival of the invading larvae.

     

Does land use change influence predation of bird nests?

Worldwide, many areas of agricultural land which were once covered with native vegetation have been converted to tree plantations. Such landscape transformation can influence the dynamics of wildlife populations through, for example, altering rates of predation (e.g. predation of nests of birds). Nest predation can influence reproductive success and, in turn, may alter populations by affecting juvenile recruitment. We quantified predation of bird nests in woodland remnants surrounded by two types of land use, grazing farmland and exotic Radiata pine (Pinus radiata) plantation. We also examined differences in predation rates between artificial and natural nests. We found both artificial and natural nests were more susceptible to nest predation in woodland remnants surrounded by a pine plantation than in woodland remnants located within farmland. Our study suggests that higher levels of nest predation may reduce occupancy of woodland remnants by small‐bodied birds over time, including species of conservation concern. This may have been occurred as a result of the conversion of semi‐cleared grazing land to exotic pine plantation.     

Infection byBeauveria bassiana ofLeptinotarsa decemlineata larvae as a consequence of fecal contamination of the integument followingper os inoculation

A study ofper os inoculated larvae was undertaken to determine if the entomopathogenic fungus,Beauveria bassiana, is able to infect the Colorado potato beetle,Leptinotarsa decemlineata, via the alimentary tract. Surface orper os inoculated larvae which were immediately surface sterilized post inoculation did not succumb to infection, whereas those larvae not sterilized became infected. Histological studies of fed or starved, agnotobiotic (with microbial flora) and axenic larvae revealed that conidia can germinate in the gut regardless of the presence of gut microflora. However, infection via the alimentary tract was never observed in fed larvae and only noted in a single starved individual. It is concluded that infections ofper os inoclated larvae occurred after surface contamination of the integument by viable conidia contained in the frass. The rate of food passage through the gut is probably important in preventingper os infections.     

Interaction between ants and fruits of<Emphasis Type="Italic"> Guapira opposita</Emphasis> (Nyctaginaceae) in a Brazilian sandy plain rainforest: ant effects on seeds and seedlings

This study examines the dispersal system of Guapira opposita in a tropical sandy rainforest in southeast Brazil. Guapira trees produce small fruits with a high protein content (28.4%) and low lipid content (0.3%), and the plant is primarily dispersed by birds. Mature fruits of G. opposita can fall spontaneously with the pulp intact, or be dropped by birds with bits of pulp attached. In either case, ground-dwelling ants rapidly remove the fruits to their nest (93% after 12 h). The ponerine ants Odontomachus chelifer and Pachycondyla striata are the main seed vectors among the ants, and together account for 56% (20 of 36) of the ant-fruit interactions recorded on the forest floor. Individual workers of O. chelifer and P. striata transport single fruits to their nests. Bits of pulp are fed to larvae and worker nestmates, and intact seeds are discarded outside the nest. Germination success in Guapira is higher for cleaned seeds (pulp removed) than for seeds coated by pulp. Guapira seedlings and juveniles are more frequent close to Odontomachus nests than at sites without such nests. Soil samples from Odontomachus nests had greater penetrability, and higher concentrations of P, K, and Ca than random soil samples. Field experiments suggest that the association between G. opposita seedlings and O. chelifer nests can potentially render the plant some protection against herbivores. Results indicate that fruit displacement by ponerine ants play an important role in the biology of G. opposita seeds and seedlings in the sandy forest, and illustrate the complex nature of the dispersal ecology of tropical tree species.     

Laboratory studies on the larval food habits of the ground beetle Amara (Curtonotus) gigantea (Motschulsky) (Coleoptera: Carabidae: Zabrini)

Ground beetles (Coleoptera: Carabidae) are important components of soil ecosystems in temperate zones, but our knowledge regarding the ecology of many species is limited. This study examined larval food habits in the ground beetle Amara (Curtonotus) gigantea (Motschulsky) using laboratory‐rearing experiments. Because this beetle is a member of the tribe Zabrini, which includes several species that exhibit granivory during larval and/or adult stages, three diet types were tested, with starvation as a control: Tenebrio larvae, mixed seeds (Bidens pilosa (Asteraceae), Setaria spp., Digitaria ciliaris (both Poaceae), and Humulus scandens (Moraceae)), and Tenebrio larvae + mixed seeds. Because of high larval mortality during overwintering under laboratory‐rearing conditions, survival and the duration of development through pre‐overwintering stages (first and second instars) were compared. Larvae fed the diet of Tenebrio larvae + mixed seeds showed the highest survival (89%), followed by the diet of Tenebrio larvae (83%), but the difference between the two treatments was not significant; similarly, developmental durations did not differ between these two diets. Larvae fed the mixed‐seeds diet showed markedly lower survival, and no larvae reached the second instar. Therefore, for A. gigantea larvae, animal food results in high larval performance, whereas seeds provide a low value diet; animal food is essential for larval development, but seeds provide no benefit, even as a dietary supplement. Overall, the present results suggest that A. gigantea larvae are omnivorous but with a mainly carnivorous food habit.     

Life cycle of Anthracophora rusticola (Coleoptera: Cetoniidae) from the commensal nests of Chinese Sparrowhawks (Accipiter soloensis)

Commensal breeding habits of the Anthracophora rusticola (Coleoptera: Cetoniidae) in stick nests of carnivorous, piscivorous, and omnivorous birds were recently reported, but the detailed life history of the scarab beetle has not been thoroughly elucidated. To understand the breeding cycle of the declining A. rusticola related to that of nesting Chinese sparrowhawks (Accipiter soloensis) in Korea, we examined six sparrowhawk nests from 2005 to 2008 and reared larvae and cocoons in a cage in 2008. Each sparrowhawk nest hosted 11.3 ± 3.0 larvae and cocoons, implying that sparrowhawk nests might be the most important nesting resource of the beetles in Korea. The beetles may lay their eggs between late May and early July after nest building by sparrowhawks. Larvae were observed from July to August in the sparrowhawk nests, and adult beetles emerged in September after a mean pupal period of 25.5 days. Our results on the coinciding breeding of two commensal taxa over three months from May to September may provide key information regarding the life history of the commensal scarabid beetle and potential causes of the concurrent decline of both taxa in Korea.     

An experiment on ant predation in soil using a new bait trap method

To examine which species of ant are underground predators, we invented a simple bait trap using live mealworms as bait. A total of 75 bait traps were buried in soil at various depths (10, 20, 30 and 50 cm) to investigate the vertical distribution of predatory ants. The ants captured in approximately 50% of the traps were mostlyTetramorium caespitum andSolenopsis japonica. Solenopsis japonica was captured at greater depths (>30 m) thanT. caespitum. Eight kinds of soil invertebrate (the earthworm, wood louse, pill bug, millipede, adults of the dung beetle and carabid beetle, larvae of a cetoniine beetle and the earwig), placed in traps at a depth of 10 cm, varied greatly in attractiveness and vulnerability to ant predation. The earthworm and the wood louse were both attractive and vulnerable to ant predation, whereas the pill bug, the dung beetle and the millipede were attractive but not vulnerable. The larvae of a cetoniine beetle, the carabid beetle and the earwig were mostly unattractive.     

Nest height is affected by lamppost lighting proximity in addition to nestbox size in urban great tits

Both natural and artificial light have proximate influences on many aspects of avian biology, physiology and behaviour. To date artificial light at night is mostly considered as being a nuisance disrupting for instance sleep and reproduction of diurnal species. Here, we investigate if lamppost night lighting affects cavity‐nesting bird species inside their breeding cavity. Nest height in secondary cavity‐nesting species is the result of trade‐offs between several selective forces. Predation is the prevailing force leading birds to build thin nests to increase the distance towards the entrance hole. A thin nest may also limit artificial light exposure at night. Yet, a minimum level of daylight inside nesting cavities is necessary for adequate visual communication and/or offspring development. Against this background, we hypothesised that avian nest‐building behaviour varies in response to a change in night lighting. We monitored nest height of urban great tits Parus major during six years and found that it varied with artificial light proximity. The birds built thinner nests inside nestboxes of various sizes in response to increasing lamppost night light availability at the nest. In large nestboxes, the nests were also thinner when a lamppost was present in the territory. Whether this relationship between artificial night lighting and nest height reflects a positive or negative effect of urbanisation is discussed in the light of recent experimental studies conducted in rural populations by other research groups.     

Effects of Selected Fungicides and the Timing of Fungicide Application on Beauveria bassiana-Induced Mortality of the Colorado Potato Beetle (Coleoptera: Chrysomelidae)

Four fungicides used for controlling foliar diseases of potato (Solanum tuberosum) were evaluated under field and laboratory conditions for their effects on the infectivity and sporulation of Beauveria bassiana when used as a control for the Colorado potato beetle, Leptinotarsa decemlineata (CPB). We investigated the direct effects of fungicides on B. bassiana-induced CPB mortality and the effect of time between fungicide and B. bassiana application. Effects of fungicide on conidial survival in the soil and on foliage were examined in the field. Significantly more larval mortality was observed when larvae were sprayed with B. bassiana than with the water control. Fungicide had no significant effect on larval mortality in the field. In the laboratory, survival of larvae was significantly lower among larvae fed fungicide-treated foliage. B. bassiana-induced mortality in the laboratory was observed only when larvae were fed foliage treated with copper hydroxide or water. Larvae fed mancozeb- or chlorothalonil-treated foliage experienced high mortality regardless of B. bassiana treatment. While there was no significant effect of fungicide on B. bassiana sporulation on cadavers in the field, a pattern emerged that indicated higher proportions of cadavers producing conidia in plots sprayed with water or copper hydroxide than in plots sprayed with chlorothalonil or mancozeb. Survival of B. bassiana conidia in the soil and on foliage was significantly greater in plots treated with copper hydroxide or water than in plots treated with mancozeb or chlorothalonil. Fungicides such as copper hydroxide may be less deleterious to the fungus than mancozeb and chlorothalonil.     

Foraging behaviour of nest predators at open-cup nests of woodland passerines

Nest predation patterns and processes cannot be understood without studying the behaviour of predators. I videotaped the behaviour of 22 species of predators at 171 depredated nests of 13 passerine species, in woodland in the Czech Republic. About 32% (60/187) of all events occurred during the night; mammals accounted for 95% (57/60) and 22% (28/127) of nocturnal and diurnal predation, respectively. About 67% (57/85) of mammalian predation, but only 3% (3/102) of avian predation, occurred during night. Multiple predations by the same species were detected in at least 7% (6/82) and 42% (37/88) of nests depredated by mammals and birds, respectively. Martens Martes martes/foina took nest content mostly all at once; birds (mainly Jay Garrulus glandarius) revisited partially depredated nest during 1–4 consecutive days. Martens stayed at the depredated nest about five times longer than Jays. Martens spent similar time at nests with eggs and nestling, while Jays stayed about twice longer at nests with eggs. Mammals consumed eggs always at the nest (23/23), but took nestlings away in at least 48% (31/64) cases. Birds took the eggs and nestling away in at least 31% (18/58) and 76% (71/94) cases, respectively. Predator visits to active nests without taking the content, repeated partial predation and revisitation of previously depredated nests suggest an effect of memory on predator’s foraging behaviour.