Dispersal pattern of the sand fly Lutzomyia neivai (Diptera: Psychodidae) in a cutaneous leishmaniasis endemic rural area in Southeastern Brazil

The dispersal pattern of the sand fly Lutzomyia neivai was studied through mark-release-recapture experiments in an American cutaneous leishmaniasis endemic rural area in Southeastern Brazil. Over 6500 specimens were marked with fluorescent powder and released in forest edge and peridomicile habitats from August to November 1999, February and April 2000. Recapture attempts were made using Shannon and CDC traps up to eight successive nights after releases. A total of 493 (7.58%) specimens were recaptured. The number of recaptured males and females of L. neivai in CDC traps was not affected by the distance between the trap and the release points. Approximately 90% of males and females recaptured in CDC traps were caught up to 70 m from the release points. The maximum female flight range recorded was 128 m. The average flight range per day was less than 60 m for males and females. Of the flies released in forest edge, approximately 16% of the recaptured females were caught in Shannon traps in the peridomicile habitat. The results indicate that the movements of L. neivai are spatially focal and the possibility of dispersion from forest to peridomicile habitat may be an important way of contracting leishmaniasis in dwellings.     

Comparative efficacy of three suction traps for collecting phlebotomine sand flies (Diptera: Psychodidae) in open habitats

The efficacy of three suction traps for trapping phlebotomine sand flies (Diptera: Psychodidae) was compared. Traps were baited with Co₂ and used without any light source. CO₂‐baited CDC traps were evaluated either in their standard downdraft orientation or inverted (iCDC traps). Mosquito Magnet‐X (MMX) counterflow geometry traps were tested in the updraft orientation only. Both updraft traps (iCDC and MMX) were deployed with their opening ～10 cm from the ground while the opening of the downdraft (CDC) trap was ～40 cm above ground. Comparisons were conducted in two arid locations where different sand fly species prevail. In the Jordan Valley, 3,367 sand flies were caught, 2,370 of which were females. The predominant species was Phlebotomus (Phlebotomus) papatasi, Scopoli 1786 (>99%). The updraft‐type traps iCDC and MMX caught an average of 118 and 67.1 sand flies per trap night, respectively. The CDC trap caught 32.9 sand flies on average per night, significantly less than the iCDC traps. In the Judean desert, traps were arranged in a 3×3 Latin square design. A total of 565 sand flies were caught, 345 of which were females. The predominant species was P. (Paraphlebotomus) sergenti Parrot 1917 (87%). The updraft traps iCDC and MMX caught an average of 25.6 and 17.9 sand flies per trap per night, respectively. The CDC trap caught 7.8 sand flies on average per night, significantly less than the iCDC traps. The female to male ratio was 1.7 on average for all trap types. In conclusion, updraft traps deployed with their opening close to the ground are clearly more effective for trapping sand flies than downdraft CDC traps in open habitats.     

Improving the selectivity of water traps for monitoring populations of the cabbage root fly

Traps placed within brassica crops to monitor changes in cabbage root fly activity could be made more selective by painting black the inner wall of the standard fluorescent yellow water-traps. Traps could also be made more selective by covering them with cylinders of Netlon mesh, although this procedure reduces the numbers of cabbage root fly caught by about 70%. Of the single-coloured traps tested, those painted “marigold” yellow were the most selective in capturing female cabbage root flies. Although white and certain blue traps were as effective as the best yellow traps at capturing cabbage root flies, such traps should be avoided, as they catch 4–5 times as many of the closely-related bean seed fly. The presence of bean seed flies makes cabbage root fly identification more difficult and adds considerably to the time required to sort trap catches.     

Understanding Bactrocera dorsalis trapping to calibrate area-wide management

Knowing the dispersal of released insects and estimating the size of field populations are keys to the successful implementation of area-wide management (AWM) programmes based on the sterile insect technique (SIT), as they determine the release strategy of sterile males. Mark–release–recapture (MRR) is a common method used to estimate field populations and spatiotemporal dynamics. However, the extent to which the pest is attracted to lures is often difficult to identify, thereby biasing extrapolation to movement patterns and population size. We performed MRR experiments on the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), in a fruit-growing area in Senegal. Methyl eugenol and protein baits were used to trap males and females, respectively. After studying the suitability of marking B. dorsalis with fluorescent pigments at the laboratory, two releases of marked sterile flies were organized in the centre of an organic mango orchard, first in the late mango fruiting stage and second in the fruit setting stage. Traps were placed symmetrically along a 250 and 500 m radius from the release point. A very small fraction of the released individuals was recaptured: 0.45% in the first release and 3.08% in the second. Trapping of both sterile and wild flies was completely anisotropic. Sterile flies were mostly trapped at a relatively short distance (250 m) from the release point, in the first two days. Male trapping using methyl eugenol was highly effective, whereas the response of females to food bait traps was low. The direction of the wind was the main driver of recapture, with flies heading upwind. The results underline the importance of taking the odour plume around the traps into account when estimating populations, and the heterogeneous spread of the wild population in the landscape for the set-up of the release strategy of sterile insects for SIT-based AWM.     

Effect of trap background on cabbage root fly landing and capture

Pieces (600 mm × 800 mm) of coloured board, plastic sheeting and woven materials, place beneath water traps prevented the traps from becoming soiled during rainy weather. Such backgrounds are not recommended for use with traps for monitoring populations of the cabbage root fly (Delia radicum L. — Diptera: Anthomyiidae), however, as, instead of increasing trap catch they reduced the numbers of female flies caught by 70%–90%. The main effect was that the visually attractive stimuli from the introduced backgrounds competed with those from the trap. A white background competed with a white trap on a direct fly/unit area basis. Green backgrounds stimulated males to land and the vertical stems of both real and artificial grass induced trivial flights that resulted in greater numbers of males entering traps resting on short grass. Most females were caught over bare soil. To minimize the variation in catch between traps used for monitoring cabbage root fly populations, the background beneath each trap should be similar. For maximum capture, the background should be of grass for male flies and of bare soil for female flies. Care is required if data from traps within mulched crops are used to make pest control decisions, as they will underestimate considerably the numbers of flies in such crops.     

Studies on the effectiveness of coroplast sticky traps for sampling stable flies (Diptera: Muscidae), including a comparison to Alsynite

Stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), are a blood-feeding pest of cattle worldwide. A new trapping material, Coroplast, was compared with Alsynite sticky traps based on the number, sex, and parity of stable flies caught. Coroplast sticky traps caught more stable flies than Alsynite (trap catches of 2384 versus 753 on 15 traps), with this increase attributed to catching more males (1531 versus 532) and nulliparous females (817 versus 175); parous catches were similar (36 versus 46). The spectral reflectance of Alsynite and Coroplast sticky traps is reported. We also examine Coroplast traps in detail with respect to trap color. Although clean sheets of Alsynite had a higher solar reflectance than Coroplast (90 versus 82% at 450 nm), Coroplast with debris had a higher reflectance than debris-covered Alsynite (62 versus 30% at 450 nm). White Coroplast was most effective, followed by closely by gray. Black and blue were the least effective trapping colors.     

The relationship between the size of yellow water traps and catches of aphids

Yellow water traps are often used for sampling populations of flying aphids. This note suggests that the size and probably the shape of traps should be standardised, because trapping efficiency (nos. caught/unit area), and the relative attractiveness of traps to different species, depends on trap size. Aphidologists using water traps to compare mixed populations of flying aphids, should therefore compare catches from different traps with caution.Traps of three sizes were made up from individual trays, each 29×21.5×5cm, and painted Hansa yellow inside; 1 tray alone, 4 arranged in a 2×2 rectangle, and 9 in a 3×3 rectangle, gave trapping surfaces of approx. 625, 2500 and 5700 cm² respectively. The traps were half-filled with water plus a drop of detergent, placed on bare land and daily catches collected on 19 days in June and July 1966.     

The effectiveness of traps used currently for monitoring populations of the cabbage root fly (Delia radicum)

Six different types of traps were compared for capturing adults of Delia radicum. Cone traps caught so few flies that it seems inadvisable for them to be used for monitoring populations of this pest. All the other traps tested were suitable for monitoring D. radicum populations. When expressed on a trap for trap basis, the large 1800 cm² Canadian traps caught most flies. When expressed as the numbers of flies caughthnit area of trapping surface, most flies were caught in the water traps. Similar numbers of D. radicum, D. platura, syrphids, blowflies and a tachinid, Eriothrix rufomaculatus were caught per unit area on each of three different vertical sticky traps. Although water traps have the advantage that they catch about 5 times as many females D. radicum/unit area as the most effective vertical sticky traps of a comparable size, their disadvantage is that they catch about 10 times as many beneficial syrphids. The reasons why water traps are so effective against D. radicum are discussed, with details of how to convert water-trap data to sticky-trap equivalents, and vice versa.     

Attraction of the West Indian fruit fly to mango fruit volatiles

In this study, we investigated the attraction of West Indian fruit fly, Anastrepha obliqua (Macquart) (Diptera: Tephritidae), to volatiles of three mango [Mangifera indica L. (Anacardiaceae)] cultivars in field cage tests. The number of flies captured with Multilure traps baited with Amate mature green mangoes was significantly higher than that captured in traps baited with Coche and Ataulfo fruits. There was no significant difference between the number of flies captured in traps baited with Coche or Ataulfo mangoes. Gas chromatography‐mass spectrometry analysis of mango fruit volatiles identified 24, 22, and 19 compounds for Amate, Ataulfo, and Coche mango cultivars, respectively. A principal component analysis of the volatiles revealed that the Amate mango was more distant from the Ataulfo mango, and the latter cultivar was closer to the Coche mango. The compounds myrcene, α‐pinene, β‐selinene, and trans‐β‐ocimene were the most abundant in Amate mangoes, whereas 3‐carene, β‐selinene, terpinolene, and α‐pinene were the predominant compounds of Ataulfo cultivars. In the Coche mango, the predominant compounds were 3‐carene, β‐selinene, terpinolene, and limonene. Traps baited with a blend of myrcene, α‐pinene, and trans‐β‐ocimene captured more A. obliqua females and males than control traps. Flies were more attracted to the Super Q volatile extracts of Amate mango than to the three‐component blend formulated in a ratio of 1:1:1. However, there was no significant difference between the number of flies caught by traps baited with Amate mango extracts and that caught by traps baited with the three‐blend component when this was formulated according to the relative proportions in the mango extracts. Traps baited with myrcene, the major component, caught fewer flies than traps baited with Amate mango extracts.     

Preference of the cabbage root fly, Delia radicum (L.), for coloured traps: influence of sex and physiological status of the flies, trap background and experimental design

Abstract. Catches of Delia rudicum (L.) (Diptera: Anthomyiidae) were compared in water traps that reflected predominantly wavelengths shorter (violet and blue traps) and longer (green and yellow traps) than 500 nm.Traps were positioned in choice and no-choice situations against backgrounds of bare soil and weeds in the field and against backgrounds of brown and green paper in the laboratory.The physiological status of the flies was modified in the laboratory by denying them access to food sources and oviposition sites.
Males discriminated significantly more clearly than females between yellow and blue traps.The discrimination between yellow and blue traps was significantly more pronounced when the traps were presented in the choice than in the no-choice situation in both sexes.Green background (weeds and green paper) was highly preferred for landing and thus competed with the traps to such an extent that few flies were caught when non-preferred violet and blue traps were sited on green backgrounds.Flies seldom landed on the brown background (soil and brown paper) which resulted in the relative increase of catches in the non-preferred violet and blue traps.The preference for yellow traps was innate even in young flies with immature egg-follicles.Females that were ready to lay eggs, even those deprived of an oviposition site till the age of 8 days, also preferred yellow traps.In the no-choice situation, flies deprived of food landed with the same frequency in yellow and blue traps.Food deprivation, however, did not affect preference for yellow traps over the blue traps presented in a choice situation.     

Assessing the age of field female wheat bulb flies (Leptohylemyia coarctata)

From 1967 to 1971, wheat bulb fly females caught by sweeping from a number of localities contained mature eggs from the third week of July to the end of August. In 1971 when female wheat bulb flies were caught by sweeping, by white water traps, by suction traps as well as by light traps, the first flies containing mature eggs were caught 29 days after the first detected emergence while the first batch was laid 29–58 days after first emergence. The peak period of egg laying occurred in the fourth week of July, 24–38 days after the peak emergence. The second batch of eggs was laid when the flies were 8 weeks old, 29 days after the first; the peak for this batch was 35 days after the first. A few females laid a third batch of eggs 28 days after the first record of the laying of the second batch. A female that lives sufficiently long to lay the third batch of eggs is at least 12 weeks old. In 1970, when emergence started earlier in June, ripening and laying of eggs of the three batches was also earlier. After the harvest of cereal crops more females were caught by white water traps placed on the fallow than by other methods. The most important pathogen affecting adult wheat bulb flies was a fungus, probably Entomophthora muscae. When infection occurred early in July, fewer eggs from the first batch were laid than when infection developed later. Fewer flies were infected in 1971 than in 1970. To be effective against wheat bulb fly in the early spring, control measures-should be applied against adults before their eggs mature in early July of the preceding year.     

Effect of trap type, trap color, trapping location, and pheromone dispenser on captures of male Palpita unionalis (Lepidoptera: Pyralidae)

Field studies were conducted to evaluate the influence of trap design, trapping location, type of pheromone dispenser, and trap color on the capture of Palpita unionalis (Hübner) males, in olive groves. The experiments were carried out in two regions, Alexandria (northern Greece) and Oropos (central Greece), where olives are cultivated. In both regions, the majority of the males (> 70% of the total) were caught from late autumn to early winter, whereas < 1% was caught during July and August. Among the trap types used, the Funnel was significantly more attractive than Delta, Pherocon 1C, and Pherocon II traps. More males were caught in traps placed at the periphery of the groves than those placed in the center. Among the four colored traps tested, white traps were the most effective. However, a significant difference in trap catches was found between white and brown traps. Traps baited with red rubber septa captured more males than those baited with the white one. The use of these parameters in monitoring and managing P. unionalis is discussed.     

Use of odour-baited sticky boards to trap tabanid flies and investigate repellents

Tabanid flies were captured in a sheep pasture in Hungary using black plastic boards (30 × 30 cm), coated with an adhesive sheet, which were either unbaited or baited with ethane-ethiol or Swormlure-4. Five species of tabanid were caught, of which Tabanus tergestinus was caught in the greatest number (87% of 192). The sex ratio of T. tergestinus on unbaited boards was not statistically significantly different to equality. However, on baited boards, males were significantly more numerous, probably due to a repellent effect of the odours on female tabanids. Because of the importance of repellents in tabanid control, this result encourages the exploration of a wider range of compounds as tabanid repellents than are used at present. Sticky boards offer a simple technique for trapping both sexes of tabanids, especially males, which are poorly represented in many tabanid traps.     

Dispersal of the cabbage root fly

The dispersal rates of wild and culture cabbage root flies Erioischia brassicae were determined in release-recapture experiments at Wellesbourne in 1971–3. The experiments were concerned mainly with the first 7 days of adult life. The flies, released from nine locations in the area, were recaptured in yellow water-traps. Dispersal was affected by wind, rain and the terrain the flies were crossing. The flies least often recaptured were those released into the host crop when 6–12 days old. The results indicated the following pattern of behaviour. Flies moved little during the first 2 days of adult life but by the third day both sexes had dispersed to c. 100 m from the release point. Flies are known to mate about the fourth day and after this the males continued to disperse at c. 100 m per day for the three subsequent days. ‘Wild’ females from field-collected pupae carried out a ‘migratory’ flight, however, and dispersed at c. 1000 m per day during the fifth and sixth days, the days preceding the start of oviposition. Similar rates of dispersal were recorded from flies released across host crop and non-host crop areas. Some females did not stop at the first crop they encountered. The culture females from the laboratory-reared pupae dispersed only c. one-third of the distance of the wild females. There was considerable intermingling of local populations. The percentage recapture of young culture and wild flies released during the pre-oviposition period of this species was 38 ± 4 and 19 ±4 for males, and 15 + 2 and 8+1 for females, respectively. The dispersal range of the cabbage root fly is probably within a 2000–3000 m radius of the site of infestation.     

Effect of host odours on trap catch composition of Glossina pallidipes in Kenya

The effect of odour attractants on the composition of samples of Glossina pallidipes Austen was investigated by comparing the age and nutritional status of flies caught in unbaited biconical traps with those caught in traps baited with cow urine and acetone. For both male and female flies, baited traps caught more flies with significantly higher fat content than did unbaited traps. Thus the samples from baited traps were more representative of the population as a whole: males showed a fuller range of the fat/haematin conditions known to occur in the field and proportionately more females were in later stages of the pregnancy cycle, than from unbaited traps.     

Capture of Mediterranean fruit flies (Diptera: Tephritidae) in dry traps baited with a food-based attractant and Jackson traps baited with trimedlure during sterile male release in Guatemala

Captures of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in Jackson traps baited with trimedlure were compared with captures in cylindrical open-bottom dry traps baited with a food-based synthetic attractant (ammonium acetate, putrescine, and trimethylamine). Tests were conducted in Guatemala during a sterile male release program in an area where wild flies were present in low numbers. More wild and sterile females were captured in food-based traps, and more wild and sterile males were captured in trimedlure traps. The food-based traps captured almost twice as many total (male plus female) wild flies as the trimedlure traps, but the difference was not significant. Females made up approximately 60% of the wild flies caught in the food-based attractant traps; the trimedlure traps caught no females. The ratio of capture of males in trimedlure traps to food-based traps was 6.5:1 for sterile and 1.7:1 for wild flies. Because fewer sterile males are captured in the food-based traps, there is a reduction in the labor-intensive process of examining flies for sterility. The results indicate that traps baited with food-based attractants could be used in place of the Jackson/trimedlure traps for C. capitata sterile release programs because they can monitor distributions of sterile releases and detect wild fly populations effectively; both critical components of fruit fly eradication programs by using the sterile insect technique.     

A STUDY OF A FIELD POPULATION OF THE BLOWFLIES LU CILIA CAESAR (L.) AND L. SERICATA (MG.)

Attempts to measure the dispersion, population density and longevity of blowflies are described. The experiments were made at Aber, Caernarvonshire, in 1943 on a narrow strip of coastal farm land (if x f ml.). Two liberations of laboratory-bred Lucilia sericata (Mg.) were made. On the second occasion 286 flies of each sex were marked, and nine males and nineteen females were captured, the last capture occurring 15 days after liberation. The population density of this species was estimated to be approximately seven males and sixteen females per acre for the 840-acre strip on the day of the second liberation.
On 24 days during the period 20 August–20 September 1943, field-caught L. caesar (L.) females were marked, and trapping both by meat and chemical baits was continued for a further 3 weeks. 3600 females were marked, 847 being recaptured at least once, and sixteen on at least four occasions. In the later part of the blowfly season, a life of 5–6 weeks is apparently not unusual for L. caesar females. The population drawn upon by the traps at the liberation centre fluctuated between 700 and 30,000 during the 4-week period. This may have represented a very localized concentration equivalent to 6–238 females per acre. Dispersion of marked L. caesar was low. On the assumption of a maximum spread of 5 miles, some 63 % of the marked flies remained within 4 mile of the liberation centre.     

Role of visual and olfactory stimuli in host finding of adult cabbage root flies, Delia radicum

Visual host finding and form recognition by the cabbage root fly, Delia radicum, were studied using four shapes of yellow sticky traps as plant models. Cross, disc, and Y traps caught similar numbers of flies. Cross traps caught more females than vertical or horizontal rectangular traps. Black borders did not increase rectangle trap catches. Discs (8 cm diam.) at ground level caught more females than discs at 40 cm above ground. Larger discs (11.2 and 13.8 cm diam.) caught more females per trap than 8 cm diam. discs, but not as many per unit area.Volatile mustard oils were added to sticky cross traps as single and multiple-component baits. Traps with multiple-component baits did not consistently catch more females than single baited traps. Yellow traps baited with isothiocyanates caught 4–7 times as many females as clear plastic allylisothiocyanate (ANCS)-baited traps.Results indicated yellow discs or crosses at ground level beited with ANCS effectively monitored female D. radicum. Main factors affecting landing of female D. radicum are suggested to be color of substrate, height above ground, presence of host volatiles in vicinity, visual prominence, and area of attractive color. The view that host finding in some insects is mediated by complex responses to multichannel stimuli was supported.

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Résumé L'étude de la perception visuelle et de la reconnaissance des formes par les D. radicum adultes a été réalisée en utilisant des pièges jaunes gluants de quatre formes différentes comme leurres de plantes. Des pièges en croix, en disque et en Y ont permis la capture des mêmes nombres de mouches. Plus de femelles ont été capturées avec des pièges en croix qu'avec des pièges rectangulaires verticaux ou horizontaux. Les captures n'ont pas augmenté avec des pièges bordés de noir. Des disques de 8 cm de diamètre disposés au niveau du sol ont permis la capture de plus de femelles que des disques à 40 cm au-dessus du sol. La capture par piège a été supérieure avec des pièges de 11,2 et 13,8 cm de diamètre qu'avec ceux de 8 cm, mais moindre par unité de surface.Des essences volatiles de moutarde ont été ajoutées aux pièges en croix comme appâts simples ou composés. Les pièges avec appâtes composés n'ont pas été significativement plus efficaces que les pièges à appâts simples. Les pièges jaunes appâts avec de l'isothiocyanata ont entraîné la capture de 4 à 7 fois plus de mouches que des pièges en plastique transparent appâtés avec de l'allylisothiocyanate (ANCS). Les résultats ont montré que des disques ou des croix jaunes appâtés avec de l'ANCS au niveau du sol permettent d'organiser un avertissement agricole contre D. radicum. Les principaux facteurs intervenant dans l'atterrissage des femelles de D. radicum semblent être la couleur du substrat, l'élévation audessus du sol, le contraste visuel, la présence de substance de l'hôte dans le voisinage, et l'aire d'attractivité de la couleur. En conclusion, il est exact de considérer que la perception de l'hôte est provoquée chez quelques insectes par une réponse complexe à des stimuli multicanaux.

     

Comparison of male and female emerald ash borer (Coleoptera: Buprestidae) responses to phoebe oil and (Z)-3-hexenol lures in light green prism traps

We conducted trapping experiments for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in Michigan, U.S.A., and Ontario, Canada, to compare unbaited light green sticky prism traps with traps baited with phoebe oil, (Z)-3-hexenol (Z3-6:OH), or blends of other green leaf volatiles (GLVs) with Z3-6:OH. Traps were placed in the lower canopy of ash trees (Fraxinus spp.). Catches with Z3-6:OH-baited traps showed a significant male bias and these traps caught significantly more males than the unbaited controls at both sites. They were also superior to phoebe oil-baited traps and those baited with GLV blends. Catches with phoebe oil showed a significant female bias but there was no difference in the number of females captured between traps baited with phoebe oil or Z3-6:OH lures. Catches were analyzed at regular time intervals to examine the response of A. planipennis to the lures over the course of the flight season. Z3-6:OH-baited traps consistently caught more males than the controls at each interval throughout the flight season. Catches of females with Z3-6:OH and phoebe oil were significantly better than the controls early in the flight season but declined to control levels by midseason. Our results suggest that Z3-6:OH-baited green traps placed in the ash canopy would be a superior lure for detecting and monitoring A. planipennis throughout the flight season.     

Behavioural responses of stable flies to cattle manure slurry associated odourants

Stable flies (Stomoxys calcitrans [Diptera: Muscidae] L.) are blood‐feeding synanthropic pests, which cause significant economic losses in livestock. Stable fly antennae contain olfactory sensilla responsive to host and host environment‐associated odours. Field observation indicated that the abundance of stable flies increased significantly in grasslands or crop fields when cattle manure slurry was applied. Major volatile compounds emanating from manure slurry were collected and identified. Behavioural responses of stable flies to those compounds were investigated in laboratory bioassays and field‐trapping studies. Results from olfactometer assays revealed that phenol, p‐cresol and m‐cresol were attractive to adult stable flies. When tested individually, attraction was higher with lower dosages. Stable flies were most attracted to blends of phenol and m‐cresol or p‐cresol. Traps with binary blend lures caught more stable flies in field trials as well.