Attractive Bait Research Articles

Field experiments of Anopheles gambiae attraction to local fruits/seedpods and flowering plants in Mali to optimize strategies for malaria vector control in Africa using attractive toxic sugar bait methods

BackgroundBased on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB) methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. The ATSB approach uses fruit or flower scent as an attractant, sugar solution as a feeding stimulant, and an oral toxin. The ATSB solutions are either sprayed on vegetation or suspended in simple bait stations, and the mosquitoes ingesting the toxic solutions are killed. As such, this approach targets sugar-feeding female and male mosquitoes. This study examines the attractiveness of African malaria vectors to local fruits/seedpods and flowering plants, key biological elements of the ATSB approach for mosquito control.MethodsThree field experiments were conducted at sites in Mali. The attraction of Anopheles gambiae s.l. to 26 different local fruits and seedpods was determined at a site in the semi-arid Bandiagara District of Mali. Wire mesh glue traps with fruits/seedpods suspended on skewers inside were set along a seasonal lagoon. Seven replicates of each fruit/seedpod species were tested, with a water-soaked sponge and a sugar-soaked sponge as controls. The attraction of An. gambiae s.l. to 26 different types of flowering plants was determined at a site near Mopti in Mali. The flowering plants held in a water-filled buried container were tested using the same glue traps, with controls including water only and sugar solution. Six replicates of each selected plant type were tested on transects between rice paddies. Additional studies using CDC light traps were done to determine the relative densities and periodicity of An. gambiae s.l. attraction to branches of the most highly attractive flowering plant, branches without flowers, human odor, and candescent light.ResultsOf the 26 fruits and seedpods tested, 6 were attractive to An. gambiae s.l. females and males, respectively. Guava (Psidium guajava) and honey melon (Cucumis melo) were the two most attractive fruits for both females and males. Of the 26 flowering plants tested, 9 were significantly attractive for females, and 8 were attractive for males. Acacia macrostachya was the most attractive flowering plant. Periodicity studies using this plant showed peaks of An. gambiae s.l. attraction between 1930 and 2200 h and 0400-0500 h, which differed considerably from the response to human odors, which expectedly peaked at around midnight.ConclusionThese field experiments in Mali highlight that female and male An. gambiae s.l. have pronounced differences in attraction for diverse types of indigenous fruits/seedpods and flowering plants. The identification of attractive fruits and seedpods shows that a variety of indigenous and locally abundant natural products could potentially be used as juices to make ATSB solution for mosquito control. As well, the simple methods used to identify the most attractive flowering plants provide valuable insights into the natural history of sugar feeding for An. gambiae s.l. These observations can be used to guide future strategies for employing ATSB methods for malaria vector control in Africa. They also provide a basis for subsequent chemical analysis and development of attractive baits for mosquito control.

Evaluation of Lurex 3™, Octenol, and CO2Sachet as Baits in Mosquito Magnet® Pro Traps Against Floodwater Mosquitoes

Field evaluation of Lurex 3, 1-octen-3-ol (octenol), and CO2 sachet as baits in Mosquito Magnet Pro traps (MMP) for collecting adult mosquitoes was conducted at 2 different locations in northeast Florida. A total of 18 species of mosquitoes were collected by the MMP baited with the 3 attractant baits in St. Augustine, FL. The MMP baited with octenol collected significantly more mosquitoes than the traps baited with Lurex 3 and the CO2 sachet. A total of 6 floodwater mosquito species were collected by the MMP baited with the 3 attractant baits in Elkton, FL. The MMP baited with Lurex 3 or octenol collected more mosquitoes than the MMP baited with CO2 sachet or MMP alone.

Exploring a new biodiversity frontier: subterranean ants in northern Australia

Although it is common for ant surveys to uncover previously uncollected species, a recent study of subterranean ants in Amazonian Ecuador has indicated that an entire ant fauna may remain largely undiscovered. Here we report on the first systematic investigation of subterranean ants in northern Australia, in order to assess the extent to which the high abundance and diversity of subterranean ants in Amazonia is apparent in tropical Australia. We use a novel sampling technique that combines elements of an attractant bait and a pitfall trap, and allows many traps to be deployed simultaneously. Our main study was conducted at three closely approximated sites in Darwin, where the local ant fauna has been intensively surveyed using conventional (above-ground) sampling techniques. The 720 traps deployed resulted in 421 species records, representing 29 species from 17 genera. Sixteen of these species have cryptobiotic morphology, with four recorded here for the first time. Remarkably, one of these four (a blind species of Solenopsis) was the second most frequently caught species in subterranean traps, with 70 records. Ant abundance, species richness and composition varied markedly between sites, despite site similarity in soils and vegetation. Total ant records were greater in the middle compared with start of the wet season, declined with depth, and were greater after 4 days than one. Sampling at six sites in the Mitchell Falls area of the northern Kimberley region, 1,200 km southwest of Darwin, also revealed several cryptobiotic species new to science, including a new genus record (Pseudolasius) for Western Australia. Our underground sampling has therefore revealed an abundant and diverse subterranean ant fauna in northern Australia, containing many cryptobiotic species not previously collected. We use our results to provide methodological guidelines for most effectively sampling this fauna. Combined with the Amazonian study, our findings indicate that a specialist subterranean ant fauna, including numerous species remaining to be discovered, might be a feature of tropical landscapes throughout the world.

The use of sex pheromones for the control of invasive populations of the crayfish Procambarus clarkii: a field study

The crayfish Procambarus clarkii is a paradigmatic example of aquatic invasive species. Native to north-eastern Mexico and south-central USA, it has today reached a worldwide distribution. Several attempts have been made to mitigate its impacts but none was successful. In this study, we have investigated in the field whether sex pheromones may be used to control invasive populations of this species. Along two canals of the study area (“Padule di Fucecchio”, Central Italy, a wetland of conservation concern), in the summer 2006, we installed 18 traps for each of four types, i.e., (1) empty traps as control, and traps containing (2) sexually receptive males, (3) sexually receptive females, and (4) food. The number, sex, and size of the crayfish captured by each trap in 2 days were recorded and compared among types. The results confirm that males are attracted by the females’ sex pheromones: the sex ratio of the crayfish captured by the traps containing females was significantly biased towards males. However, when the overall number of the captured crayfish was compared among types of trap, food appeared to be the most attractive bait. The method could be improved using purified and concentrated sex pheromone instead of live animals. The use of pheromones has not been successfully applied to control crustacean decapod invaders so far, and a multidisciplinary approach is needed to face the problem.

Composição, abundância e índice de infestação de espécies de formigas em um hospital materno-infantil de Palmas, TO

This first survey of the ant fauna in a children's hospital in the city of Palmas, state of Tocantins, compares species composition, abundance and infestation rate of ants between rainy and dry seasons, day and night periods, and among 15 hospital sectors. Forty-eight collections, being 12 diurnal and 12 nocturnal in each season using five attractive baits distributed per sector, maintained for 3h per sampling. A total of 34,309 ants were collected, distributed in 12 species: Acromyrmex sp., Brachymyrmex sp., Camponotus spp. (four morphospecies), Dorymyrmex sp., Tetramorium sp., Solenopsis globularia (Creighton), Solenopsis saevissima Smith, Tapinoma melanocephalum (Fabricius) and Paratrechina longicornis (Latreille). The hospital presented an average building infestation rate (40.3%), when compared with hospitals from other Brazilian regions. In general, there was no difference in the species composition between seasons and the period of the day, although abundance of ants was higher at night. The dry season and the nocturnal period showed the highest infestation rate, mainly by T.melanocephalum and S.globularia. Gynecologic ward, lactation unit, preconception and pediatric ward access ramp showed higher infestation rate, although these varied between seasons. The significant infestation levels by the three species above, especially in sectors with restricted access such as lactation unit, laboratory, Intensive Care Unit e surgery center, indicate potential risks for contamination of patients by multi resistant pathogens possibly present in ants' bodies, as verified in others studies.

Influence of carrion smell and rebaiting time on the efficiency of pitfall traps to dung beetle sampling

AbstractDung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are very useful insects, as they improve the chemo‐physical properties of soil, clean pastures from dung pads, and help control symbovine flies associated with bovine cattle. Their importance makes it fundamental to sample and survey them adequately. The objectives of the present study were to determine the influence of decaying insects trapped in pitfalls on the attractiveness of Moura pig Sus scrofa L. (Suidae) and collared peccary Tayassu tajacu (L.) (Tayassuidae) dung used as baits to lure dung beetles, and to establish how long these baits remain attractive to dung beetles when used in these traps. Some dung beetle species seemed to be able to discriminate against foul smell from decaying insects within the first 24 h, hence decreasing trap efficiency. This was more evident in peccary dung‐baited traps, which proved to be the least attractive bait. Attractiveness lasted only 24 h for peccary dung, after which it became unattractive, whereas the pig dung bait was highly attractive for 48 h, after which its attractiveness diminished but was not completely lost.

Honey Bee Foraging Preferences, Effects of Sugars, and Fruit Fly Toxic Bait Components

Field tests were carried out to evaluate the repellency of the Dow AgroSciences fruit fly toxic bait GF-120 (NF Naturalyte) to domestic honey bees (Apis mellifera L.). GF-120 is an organically registered attractive bait for tephritid fruit flies composed of spinosad, hydrolyzed protein (Solulys), high-fructose corn syrup (ADM CornSweet 42 high-fructose corn syrup, referred to as invertose sugar or invertose here), vegetable oils, adjuvants, humectants, and attractants. Tests were carried out with non-Africanized honey bees in February and March 2005 and 2007 during periods of maximum hunger for these bees. In all tests, bees were first trained to forage from plates of 30% honey-water (2005) or 30% invertose (2007). In 2005 bees were offered choices between honey-water and various bait components, including the complete toxic bait. In 2007, similar tests were performed except bees were attracted with 30% invertose then offered the bait components or complete bait as no-choice tests. Initially, the 2005 tests used all the components of GF-120 except the spinosad as the test bait. After we were convinced that bees would not collect or be contaminated by the bait, we tested the complete GF-120. Behavior of the bees indicated that during initial attraction and after switching the baits, the bait components and the complete bait were repellent to honey bees, but the honey-water remained attractive. Invertose was shown to be less attractive to bees, addition of Solulys eliminated almost all bee activity, and addition of ammonium acetate completely eliminated feeding in both choice and no-choice tests. These results confirm previous tests showing that bees do not feed on GF-120 and also show that honey bees are repelled by the fruit fly attractant components of the bait in field tests.

Identification of Female-produced Sex Pheromone of the Honey Locust Gall Midge, Dasineura gleditchiae

The honey locust gall midge, Dasineura gleditchiae Osten Sacken 1866 (Diptera: Cecidomyiidae) is the main pest of ornamental varieties of the honey locust tree, Gleditsia triacanthos L., in North America, and is now becoming a pest of concern in Europe. Female midges were observed to emerge in the early morning with their ovipositor extended until they mated. Volatiles were collected from virgin females in a closed-loop stripping apparatus and analyzed by gas chromatography (GC) coupled to electroantennographic (EAG) recording from the antenna of a male midge. A single EAG response was observed, which was assumed to be to the major component of the female sex pheromone. This was identified as (Z)-2-acetoxy-8-heptadecene by comparison of its mass spectrum and GC retention times on different columns with those of synthetic standards and by micro-analytical reactions. This compound was synthesized, and the individual enantiomers were produced by kinetic resolution with lipase from Candida antarctica. Analysis of the naturally-produced compound on a cyclodextrin GC column indicated it was the (R)-enantiomer. In EAG dose-response measurements, the (R)-enantiomer alone or in the racemic mixture evoked significant responses from the antennae of male D. gleditchiae, whereas the (S)-enantiomer did not. In field trapping tests, the (R)-enantiomer attracted male D. gleditchiae. The racemic compound was equally attractive, but the (S)-enantiomer was not attractive. Both the pure (R)-enantiomer or racemic (Z)-2-acetoxy-8-heptadecene, applied to red rubber septa in a dose range of 3-30 microg, constitute a strongly attractive bait in sticky traps for monitoring the flight of D. gleditchiae.

Abelhas Euglossina (Hymenoptera, Apidae) coletadas em uma monocultura de eucalipto circundada por Cerrado em Urbano Santos, Maranhão, Brasil

Machos de Euglossina foram coletados por meio de iscas-odores de benzoato de benzila, eucaliptol, eugenol, salicilato de metila e vanilina em uma monocultura de eucalipto circundada por cerrado, no município de Urbanos Santos, Maranhão. As coletas foram realizadas mensalmente, de abril de 2001 a abril de 2002, entre 8h e 16h, totalizando 96 horas de amostragem. Foram coletados 58 indivíduos de 3 gêneros e 10 espécies. Euglossa Latreille, 1802 foi o gênero mais abundante, seguido por Eufriesea Cockerell, 1909 e Eulaema Lepeletier, 1841. As espécies mais freqüentes foram Euglossa cordata (Linnaeus, 1758), Euglossa gaianii Dressler, 1982 e Euglossa modestior (Dressler, 1982). Eucaliptol foi a essência mais atrativa. As maiores freqüências de visitas ocorreram no período da manhã e as maiores abundâncias em setembro, no período de estiagem, e em dezembro, no período chuvoso.

Decline Of Anopheles sergentii and Aedes caspius Populations Following Presentation Of Attractive Toxic (Spinosad) Sugar Bait Stations In An Oasis

The effect of attractive sugar bait stations, including sucrose, juice of nectarine, slow-release substances, preservatives, red food-dye marker, and the oral insecticide spinosad, on Anopheles sergentii and Aedes caspius populations was studied in a small oasis in a southern desert of Israel. Feeding on similar baits without an insecticide was monitored as a control in a similar neighboring oasis. The insecticide caused a drastic decrease in the number of mosquitoes. Compared to the control site, the An. sergentii population was reduced to less than a tenth and that of Ae. caspius declined to a third. The majority of the mosquitoes, 76.0% of An. sergentii females and 74.8% of Ae. caspius females, were marked by the food dye in the control site.

Effect of differents baits as attractant for blowflies (diptera) at Valonguinho, Universidade Federal Fluminense, Niterói, RJ, Brazil

It was carried out a survey of blowflies in an area of the Campus (Valonguinho) of the Universidade Federal Fluminense, Niterói, Rio de Janeiro. The collections were performed with traps, using baits of fish (sardine), bovine liver, shrimps and banana. Were collected 6015 flies, Chrysomya megacephala and Lucilia eximia were the most frequent (50.55% and 21.52%, respectively). The flies were more abundant in February and March and the most attractive bait was fish (38.32%).

Control of Vespula germanica (Hym. Vespidae) populations using toxic baits: bait attractiveness and pesticide efficacy

Abstract: Our aim was to test a set of baits and pesticides for the control of yellowjacket populations in NW Patagonia (Argentina), through field trials. We tested the attractiveness of protein (fresh and freeze‐dried beef) and carbohydrate (corn syrup and honey) baits (alone and mixed) and three pesticides commonly employed to control terrestrial domestic arthropods (hydramethylnon 2%, permethrin 0.3% and chlorpyrifos 0.25%). Our results show that beef proved to be the most attractive bait tested, for Vespula germanica wasps in NW Patagonia. Honey and corn syrup alone or mixed with beef did not attract foraging wasps as did beef‐only baits throughout the wasp season. Additionally, we show that the attractiveness of lyophilized beef baits is similar to that of fresh beef. The efficacy of the insecticides tested was limited. In fact, only baiting with hydramethylnon 2% reduced wasp populations (54%) and this occurred after 72 h since poisoning. However, given the potential of insects to develop resistance to a consistent use of a single product (e.g. fipronil 0.1%), the use of hydramethylnon may allow the alternating of insecticides in specific situations. The information provided here contributes to the existent knowledge on baits and insecticides for the control of yellowjackets using toxic baits.

N‐Butyl (E)‐7,9‐decadienoate: sex pheromone component of the nettle caterpillar, Darna pallivitta

AbstractThe nettle caterpillar, Darna pallivitta (Moore) (Lepidoptera: Limacodidae), is an invasive pest on the island of Hawai’i, causing defoliation of ornamental nursery stock and posing a human health hazard due to their urticating hairs that can cause painful stings. Wind tunnel and field tests with 2–3‐day‐old moths revealed behavioral responses of males to caged females, which is indicative of a female‐released sex pheromone. Coupled gas chromatography‐electroantennogram detection (GC‐EAD) analysis of female abdominal tip extracts revealed two male electroantennographically active compounds produced by female D. pallivitta. Mass spectral analysis and subsequent synthesis identified the active compounds as n‐butyl (E)‐7,9‐decadienoate (major component) and ethyl (E)‐7,9‐decadienoate (minor component), both structurally similar to sex pheromone components previously reported from related Darna spp. Additionally, methyl (E)‐7,9‐decadienoate was identified from female abdominal tip extracts and a strong EAD response was elicited by the synthetic compound. n‐Butyl (E)‐7,9‐decadienoate was the only component detected by solid phase microextraction (SPME) collections from single calling female moths, however, the apparent absence of minor components may be a result of their lower abundance. Field trials showed significant attraction of male moths to all lures containing the n‐butyl ester, while the methyl and ethyl esters did not increase trap captures at the levels and ratios tested. Synthetic pheromone lures (2.5 mg) outperformed virgin moths as attractant baits and could be used for monitoring D. pallivitta populations of the island of Hawai’i and detection on other Hawai’ian islands and at ports and nurseries that receive plants from Hawai’i (e.g., California and Florida).

Relative Attractiveness of Baits to <I>Paratrechina longicornis</I> (Hymenoptera: Formicidae)

Exotic ant incursions are becoming more frequent around the globe, and management with toxic baits is a suitable strategy for most species. Crazy ants, (Latreille) (Hymenoptera: Formicidae), however, are notoriously difficult to attract to commercial baits, which are generally tailored to the preferences of fire ants. We tested P. longicornis preferences for various food types and commercial ant baits. Baits trialed were commercially available products Amdro, Maxforce, Xstinguish (nontoxic monitoring version), Presto, and tuna (in spring water), sugar water (25%), boric acid (1% in 25% sugar water), and deionized water. Tuna and Xstinguish, along with sugar water and sugar water + boric acid, were the most attractive baits to P. longicornis foragers. The granular baits (Maxforce, Amdro, and Presto) were not as attractive to P. longicornis foragers. A decrease in temperature from summer (30 degrees C) to autumn (23 degrees C) trials did not seem to affect the food preferences of P. longicornis. Although P. longicornis recruitment was substantially lower during trials where there was concurrent high native ant abundance and diversity, P. longicornis still recruited to preferred baits in numbers higher than any other species. Given that tuna is impractical for management programs, the effectiveness of boric acid, sweet liquid baits in eliminating P. longicornis colonies should be compared with that of the toxic version of Xstinguish. If both are effective at eliminating colonies, we recommend sweet liquid baits containing boric acid be used for small-scale incursions (one or two nests), but a more practicable solid bait, such as Xstinguish, be used for larger scale incursions (numerous nests).

Relative Attractiveness of Baits to Paratrechina longicornis (Hymenoptera: Formicidae)

Exotic ant incursions are becoming more frequent around the globe, and management with toxic baits is a suitable strategy for most species. Crazy ants, (Latreille) (Hymenoptera: Formicidae), however, are notoriously difficult to attract to commercial baits, which are generally tailored to the preferences of fire ants. We tested P. longicornis preferences for various food types and commercial ant baits. Baits trialed were commercially available products Amdro, Maxforce, Xstinguish (nontoxic monitoring version), Presto, and tuna (in spring water), sugar water (25%), boric acid (1% in 25% sugar water), and deionized water. Tuna and Xstinguish, along with sugar water and sugar water + boric acid, were the most attractive baits to P. longicornis foragers. The granular baits (Maxforce, Amdro, and Presto) were not as attractive to P. longicornis foragers. A decrease in temperature from summer (30°C) to autumn (23°C) trials did not seem to affect the food preferences of P. longicornis. Although P. longicornis recruitment was substantially lower during trials where there was concurrent high native ant abundance and diversity, P. longicornis still recruited to preferred baits in numbers higher than any other species. Given that tuna is impractical for management programs, the effectiveness of boric acid, sweet liquid baits in eliminating P. longicornis colonies should be compared with that of the toxic version of Xstinguish. If both are effective at eliminating colonies, we recommend sweet liquid baits containing boric acid be used for small-scale incursions (one or two nests), but a more practicable solid bait, such as Xstinguish, be used for larger scale incursions (numerous nests).

Dinâmica de populações de Euglossina (Hymenoptera, Apidae) em mata ciliar, Urbano Santos, Maranhão, Brasil

Machos de Euglossina foram coletados por meio de iscas-odores de benzoato de benzila, eucaliptol, eugenol, salicilato de metila, vanilina, durante um ano em área de mata ciliar, no município de Urbano Santos, Maranhão. As coletas foram realizadas mensalmente, entre 8 h e 16 h, totalizando 96 horas de amostragem. Foram amostrados 283 indivíduos, 4 gêneros e 16 espécies. Euglossa Latreille, 1802 foi o gênero mais abundante, seguido por Eufriesea Cockerell, 1909, Eulaema Lepeletier, 1841 e Exaerete Hoffmannsegg, 1817. As espécies mais freqüentes foram Euglossa modestior (Dressler, 1982), Euglossa cordata (Linnaeus, 1758), Eulaema cingulata (Fabricius, 1804), Exaerete smaragdina (Guérin-Menéville, 1845), Eulaema nigrita Lepeletier, 1841 e Euglossa gaianii Dressler, 1982. Eucaliptol foi a essência mais atrativa. As maiores freqüências de visitas ocorreram no período da manhã e a maior diversidade de espécies ocorreu no período chuvoso.

Pine monoterpenes and pine bark beetles: a marriage of convenience for defense and chemical communication

Pine-feeding bark beetles (Coleoptera: Scolytidae) interact chemically with their host pines (Coniferales: Pinaceae) via the behavioral, physiological, and biochemical effects of one class of isoprenoids, the monoterpenes and their derivatives. Pine monoterpenes occur in the oleoresin and function as behaviorally active kairomones for pine bark beetles and their predators, presenting a classic example of tri-trophic chemical communication. The monoterpenes are also essential co-attractants for pine bark beetle aggregation pheromones. Ironically, pine monoterpenes are also toxic physiologically to bark beetles at high vapor concentrations and are considered an important component of the defense of pines. Research over the last 30 years has demonstrated that some bark beetle aggregation pheromones arise through oxygenation of monoterpenes, linking pheromone biosynthesis to the host pines. Over the last 10 years, however, several frequently occurring oxygenated monoterpene pheromone components (e.g., ipsenol, ipsdienol and frontalin) have also been shown to arise through highly regulated de novo pathways in the beetles (reviewed in Seybold and Tittiger, 2003). The most interesting nexus between these insects and their plant hosts involves the late-stage reactions in the monoterpenoid biosynthetic pathway, during which isomeric dimethylallyl diphosphate and isopentenyl diphosphate are ultimately elaborated to stereospecific monoterpenes in the trees and to hydroxylated monoterpenes or bicyclic acetals in the insects. There is signal stereospecificity in both production of and response to the monoterpenoid aggregation pheromones of bark beetles and in response to␣the monoterpenes of the pines. In the California fivespined ips, Ips paraconfusus, we have discovered a number of cytochome P450 genes that have expression patterns indicating that they may be involved in detoxifying monoterpene secondary metabolites and/or biosynthesizing pheromone components. Both processes result in the production of oxygenated monoterpenes, likely with varying degrees of stereospecificity. A behavioral analysis of the stereospecific response of I. paraconfusus to its pheromone is providing new insights into the development of an efficacious bait for the detection of this polyphagous insect in areas outside the western United States. In contrast, a Eurasian species that has arrived in California, the Mediterranean pine engraver, Orthotomicus (Ips) erosus, utilizes both a monoterpenoid (ipsdienol) and a hemiterpenoid (2-methyl-3-buten-2-ol) in its pheromone blend. The stereospecificity of the response of O. erosus to the monoterpenoid appears to be the key factor to the improved potency of the attractant bait for this invasive species.

Evaluation of Potential Insect Baits for Red-Winged Blackbirds

When using DRC-1339 Concentrate, applicators have sometimes found that blackbirds will not feed on standard grain baits. While the search for more attractive baits has generally focused on alternate grains, fruits, and occasionally processed foods, a first-rate candidate may be insects. To our knowledge, no feeding tests using red-winged blackbirds have been conducted to measure consumption rates among various commercially available insects. Our results indicated that large-sized mealworms were the best bait for red-winged blackbirds during fall, whereas crickets were favored over small-sized meal¬worms and waxworms in summer. We speculate that choice was based to some extent on the quantity of fat available among the different foods. We plan to conduct similar feeding trials with European starlings.

First assessment of the orchid-bee fauna (Hymenoptera: Apidae) at Parque Estadual do Rio Preto, a cerrado area in southeastern Brazil

Male euglossine bees were sampled with chemical attractants in September 2003 at five sites at Parque Estadual do Rio Preto, Minas Gerais state, Brazil. Two sites were located in typical "cerrado" area, two in gallery forests and one in "campo rupestre" formation. We collected 222 bees of ten species; Euglossa melanotricha was the most common at every site, followed by Euglossa fimbriata, and cineole was the most attractive bait. Comparisons with Atlantic Forest fragments suggest a relatively high diversity of orchid bees in the cerrado domain.

Twig beetles, Pityophthorus spp. (Coleoptera: Scolytidae), as vectors of the pitch canker pathogen in California

AbstractTwig beetles in the genus Pityophthorus Eichhoff are known to be associated with the pitch canker pathogen, Fusarium circinatum, in California. Phoresy of the pathogen on these species has been reported to occur when insects emerge from diseased branches and when they infest disease-free, cut branch tips. To demonstrate that twig beetles can vector the pathogen, studies of phoresy and transmission were conducted in a native Monterey pine, Pinus radiata D. Don (Pinaceae), forest. Phoresy was confirmed for both Pityophthorus setosus Blackman and Pityophthorus carmeli Swaine, and P. setosus was shown to vector the pitch canker pathogen when contaminated with fungal spores and caged onto Monterey pine branches. When attractive baits were used to increase visitation to Monterey pines by P. setosus, baited trees were more likely to develop pitch canker than unbaited trees even though the beetles did not tunnel into the host to develop egg galleries. Therefore, twig beetles are competent as vectors of the pitch canker pathogen, and their vectoring activity, though requiring a wound, does not require that they establish egg galleries in the host.