Understanding the movement and dispersal patterns of released Fopius arisanus (Hymenoptera: Braconidae) parasitoids in a papaya orchard.

Implementation of augmentative biological control requires estimates of parasitoid dispersal from the release point to determine appropriate release density, spacing, and timing. This study evaluated the movement patterns of Fopius arisanus Sonan (Hymenoptera: Braconidae) parasitoids, which have historically been used to control invasive tephritid fruit flies. The wasps were released from the central point, and dispersal was monitored over time using parasitism in sentinel fruit and trap captures at 40 points radiating out from the center (15-240 m). The releases were conducted 4 times during June, July, September, and November 2006. The data showed that there were large declines in dispersal by distance. Parasitism was greatest closest to the release point, within 30 m. Parasitism was also greatest within the first 24 h of the release. After 1 wk, parasitism decreased from 41% to 1.5% within 30 m. These data correlated strongly with trap capture data, which also showed that parasitoid movement favored the SE region of our release site, roughly corresponding to the overall prevailing winds. Wind speed, relative humidity, and temperature all affected parasitoid movement during our trial, indicating the complex environmental factors that can affect release success. This is the first report of dispersal metrics for F. arisanus. Our findings are in agreement with other similar studies on braconid movement generally and suggest that frequent, high-density releases are most effective since the dispersal of F. arisanus is limited and retention in the environment is low. We discuss our results in the context of international augmentative biological control release programs.

Spinosad resistance in field populations of melon fly, Zeugodacus cucurbitae (Coquillett), in Hawaii.

BACKGROUND: Control of Zeugodacus cucurbitae, a serious agricultural pest worldwide, often includes or is dependent on the use of spinosad-based insecticides. This is especially the case in Hawaii, where GF-120, a protein bait containing spinosad as the active ingredient, has been in use as a key integrated pest management (IPM) tool against this Tephritid for the last two decades. Here, we report on resistance to spinosad [resistance ratios (RRs) and median lethal concentration (LC50 )] in Hawaii's populations of Z. cucurbitae. RESULTS: High resistance was found in populations from three farms on Oahu (RR = 102-303; LC50  = 191-567 mg L-1 ) and in a population from Maui (RR = 8.50; LC50  = 15.9 mg L-1 ). These will be problematic for control given that the most concentrated dilution ratio on the GF-120 label is 96 mg L-1 of spinosad (1 part GF-120 to 1.5 parts water). Background resistance in a naïve wild population from the Island of Hawaii (RR = 2.73; LC50  = 5.1 mg L-1 ) was relatively low compared with a spinosad-susceptible laboratory colony (LC50  = 1.87 mg L-1 ). Resistance in the three Oahu and one Maui populations declined over generations in the absence of spinosad but remained elevated in some cases. Moreover, melon flies collected from one of the Oahu farms 1 year after the cessation of spinosad use revealed high persistence of resistance. CONCLUSION: Compared with a 2008 survey of spinosad resistance, our findings indicate a 34-fold increase in resistance on one of the Oahu farms over 9 years. The evolution and persistence of high levels of resistance to spinosad in Z. cucurbitae in Hawaii highlights the need for alternative control tactics, particularly rotation of active ingredients. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

A field test on the effectiveness of male annihilation technique against Bactrocera dorsalis (Diptera: Tephritidae) at varying application densities.

Male Annihilation Technique (MAT) is a key tool to suppress or eradicate pestiferous tephritid fruit flies for which there exist powerful male lures. In the case of Bactrocera dorsalis (Hendel), a highly invasive and destructive species, current implementations of MAT utilize a combination of the male attractant methyl eugenol (ME) and a toxicant such as spinosad ("SPLAT-MAT-ME") applied at a high density with the goal of attracting and killing an extremely high proportion of males. We conducted direct comparisons of trap captures of marked B. dorsalis males released under three experimental SPLAT-MAT-ME site densities (110, 220, and 440 per km2) near Hilo, Hawaii using both fresh and aged traps to evaluate the effectiveness of varying densities and how weathering of the SPLAT-MAT-ME formulation influenced any density effects observed. Counterintuitively, we observed decreasing effectiveness (percent kill) with increasing application density. We also estimated slightly higher average kill for any given density for weathered grids compared with fresh. Spatial analysis of the recapture patterns of the first trap service per replicate x treatment reveals similar positional effects for all grid densities despite differences in overall percent kill. This study suggests that benefits for control and eradication programs would result from reducing the application density of MAT against B. dorsalis through reduced material use, labor costs, and higher effectiveness. Additional research in areas where MAT programs are currently undertaken would be helpful to corroborate this study's findings.

Effect of Lure Combination on Fruit Fly Surveillance Sensitivity.

Surveillance for invading insect pests is costly and the trapper usually finds the traps empty of the target pest. Since the successful establishment of new pests is an uncommon event, multiple lures placed into one trap might increase the efficiency of the surveillance system. We investigated the effect of the combination of the Tephritidae male lures - trimedlure, cuelure, raspberry ketone and methyl eugenol - on catch of Ceratitis capitata, Zeugodacus cucurbitae, Bactrocera tryoni, B. dorsalis, B. aquilonis and B. tenuifascia in Australia and the USA (not all species are present in each country). The increase in trap density required to offset any reduction in catch due to the presence of lures for other Tephritidae was estimated. The effect of increasing trap density to maintain surveillance sensitivity was modelled for a hypothetical population of B. tryoni males, where the effective sampling area of cuelure traps for this species has been estimated. The 3-way combination significantly reduced the catch of the methyl eugenol-responsive B. dorsalis. Unexpectedly, we found that trimedlure-baited traps that contained methyl eugenol had ×3.1 lower catch of C. capitata than in trimedlure-only-baited traps in Australia, but not in Hawaii where no difference in catch was observed, we cannot satisfactorily explain this result. Based on the data presented here and from previous research, combinations of some male lures for the early detection of tephritid flies appear compatible and where there is any reduction in surveillance sensitivity observed, this can be offset by increasing the density of traps in the area.

Effect of Physiological State on Female Melon Fly (Diptera: Tephritidae) Attraction to Host and Food Odor in the Field.

Foraging behavior of wild female melon fly, Bactrocera (Zeugodacus) cucurbitae Coquillett, a worldwide pest of economically important cucurbit crops, was examined through mark and recapture studies in both wild (Kona: dominated by the invasive weed ivy gourd, Coccinea grandis [L.] Voigt [Cucurbitaceae]), and cultivated (Kapoho: dominated by papaya, Carica papaya L. [Caricaceae] orchards) habitats on Hawaii Island. In particular, the extent to which wild melon flies and color-marked F2 females responded to cucumber odor and Solulys yeast hydrolysate laced with ammonium acetate (1%, wt/vol) according to sexual maturity stage and degree of protein hunger was documented. Kona results indicated that more wild and color-marked F2 females responded to cucumber (Cucumis sativus L. [Cucurbitaceae]) odor than to protein odor with the exception of captured wild flies without eggs, which responded similarly to protein bait and cucumber odor. Results with captured wild females and color-marked F2 females in Kapoho suggested a significant preference for cucumber odor over protein odor regardless of whether or not they had eggs in their ovaries with the exception of protein-deprived color-marked F2 females, which responded to both odors in equal numbers. Implications of these new findings based on wild melon flies in natural habitats are discussed with respect to integrated pest management control strategies with protein bait sprays used in Hawaii. The possibility of adding cucurbit volatiles to protein-based baits is discussed.

Suppression of Mediterranean Fruit Fly (Diptera: Tephritidae) With Trimedlure and Biolure Dispensers in Coffea arabica (Gentianales: Rubiaceae) in Hawaii.

To assess the potential to suppress Mediterranean fruit fly, Ceratitis capitata (Wiedemann; Diptera: Tephritidae), via mass trapping with Trimedlure (TML), we compared fly catch (as catch per trap per time period) provided by either a novel, solid, triple-lure dispenser with TML, methyl eugenol (ME), and raspberry ketone (RK) (TMR) or solid TML plugs, both without insecticides, in addition to Biolure bait stations. Work was done in a coffee plantation that had a dense C. capitata population. Three treatments were compared: 1) TMR or TML (50 traps per ha), 2) Biolure (50 traps per ha), 3) TML (25 per ha) or TMR (25 per ha) + Biolure (25 per ha), and 4) an untreated control. During coffee season, based on C. capitata captures (mean flies per trap per wk) inside plastic McPhail traps, all treatments were significantly different than the control: Biolure (9.57) = TMR (11.28) = Biolure +TMR (13.50) < Control (36.06 flies/trap/wk). During non-coffee season, all treatments were significantly different than the control and TML was significantly lower than Biolure (wax matrix bait stations): TML (0.95) < Biolure (1.43) = Biolure +TML (1.77) < Control (2.81 flies/trap/wk). Surprisingly, captures were not lower in plots treated with combinations of Biolure + TMR or TML, compared to individual plots with Biolure or TML or TMR alone. Mass trapping with either TML or TMR dispensers deserves further study as a component of Integrated Pest Management programs for C. capitata in Hawaii and may have global potential for management of C. capitata.

Chemical Degradation of TMR Multilure Dispensers for Fruit Fly Detection Weathered Under California Climatic Conditions.

Degradation models for multilure fruit fly trap dispensers were analyzed to determine their potential for use in large California detection programs. Solid three-component male lure TMR (trimedlure [TML], methyl eugenol [ME], raspberry ketone [RK]) dispensers impregnated with DDVP (2, 2-dichlorovinyl dimethyl phosphate) insecticide placed inside Jackson traps were weathered during summer (8 wk) and winter (12 wk) in five citrus-growing areas. Additionally, TMR wafers without DDVP, but with an insecticidal strip, were compared to TMR dispensers with DDVP. Weathered dispensers were sampled weekly and chemically analyzed. Percent loss of TML, the male lure for Ceratitis capitata (Wiedemann) Mediterranean fruit fly; ME, the male lure for Bactrocera dorsalis (Hendel), oriental fruit fly; RK, the male lure for Bactrocera cucurbitae (Coquillett), melon fly; and DDVP was measured. Based on regression analyses for the male lures, TML degraded the fastest followed by ME. Degradation of the more chemically stable RK was discontinuous, did not fit a regression model, but followed similar seasonal patterns. There were few location differences for all three male lures and DDVP. Dispensers degraded faster during summer than winter. An asymptotic regression model provided a good fit for % loss (ME, TML, and DDVP) for summer data. Degradation of DDVP in TMR dispensers was similar to degradation of DDVP in insecticidal strips. Based on these chemical analyses and prior bioassay results with wild flies, TMR dispensers could potentially be used in place of three individual male lure traps, reducing costs of fruit fly survey programs. Use of an insecticidal tape would not require TMR dispensers without DDVP to be registered with US-EPA.

Sublethal Effects in Pest Management: A Surrogate Species Perspective on Fruit Fly Control.

Tephritid fruit flies are economically important orchard pests globally. While much effort has focused on controlling individual species with a combination of pesticides and biological control, less attention has been paid to managing assemblages of species. Although several tephritid species may co-occur in orchards/cultivated areas, especially in mixed-cropping schemes, their responses to pesticides may be highly variable. Furthermore, predictive efforts about toxicant effects are generally based on acute toxicity, with little or no regard to long-term population effects. Using a simple matrix model parameterized with life history data, we quantified the responses of several tephritid species to the sublethal effects of a toxicant acting on fecundity. Using a critical threshold to determine levels of fecundity reduction below which species are driven to local extinction, we determined that threshold levels vary widely for the three tephritid species. In particular, Bactrocera dorsalis was the most robust of the three species, followed by Ceratitis capitata, and then B. cucurbitae, suggesting individual species responses should be taken into account when planning for area-wide pest control. The rank-order of susceptibility contrasts with results from several field/lab studies testing the same species, suggesting that considering a combination of life history traits and individual species susceptibility is necessary for understanding population responses of species assemblages to toxicant exposure.

Vision-mediated exploitation of a novel host plant by a tephritid fruit fly.

Shortly after its introduction into the Hawaiian Islands around 1895, the polyphagous, invasive fruit fly Bactrocera (Zeugodacus) cucurbitae (Coquillett) (Diptera: Tephritidae) was provided the opportunity to expand its host range to include a novel host, papaya (Carica papaya). It has been documented that female B. cucurbitae rely strongly on vision to locate host fruit. Given that the papaya fruit is visually conspicuous in the papaya agro-ecosystem, we hypothesized that female B. cucurbitae used vision as the main sensory modality to find and exploit the novel host fruit. Using a comparative approach that involved a series of studies under natural and semi-natural conditions in Hawaii, we assessed the ability of female B. cucurbitae to locate and oviposit in papaya fruit using the sensory modalities of olfaction and vision alone and also in combination. The results of these studies demonstrate that, under a variety of conditions, volatiles emitted by the novel host do not positively stimulate the behavior of the herbivore. Rather, vision seems to be the main mechanism driving the exploitation of the novel host. Volatiles emitted by the novel host papaya fruit did not contribute in any way to the visual response of females. Our findings highlight the remarkable role of vision in the host-location process of B. cucurbitae and provide empirical evidence for this sensory modality as a potential mechanism involved in host range expansion.

Captures of Wild Ceratitis capitata, Bactrocera dorsalis, and Bactrocera cucurbitae (Diptera: Tephritidae) in Traps with Improved Multilure TMR Dispensers Weathered in California.

During 2012­2013, solid Mallet TMR (trimedlure [TML], methyl eugenol [ME], raspberry ketone [RK]) wafers impregnated with DDVP (2, 2-dichlorovinyl dimethyl phosphate) insecticide were weathered during summer (8 wk) and winter (12 wk) in five California citrus-growing counties (Kern, Ventura, Orange, Tulare, and Riverside). In addition, TMR wafers without DDVP and with a Hercon Vaportape II insecticidal strip were compared with TMR dispensers with DDVP at Exeter and Riverside. Weathered treatments were shipped every week (overnight delivery) to Hawaii and frozen for a later bioassay in a 1,335-ha coffee plantation near Numila, Kauai Island, HI, where Mediterranean fruit fly, Ceratitis capitata (Wiedemann), oriental fruit fly, Bactrocera dorsalis Hendel, and melon fly, Bactrocera cucurbitae Coquillett, were all present. We compared trap captures of the three species, C. capitata, B. dorsalis, and B. cucurbitae, for the five different weathering locations. Captures of C. capitata, B. dorsalis, and B. cucurbitae with Mallet TMR dispensers (with DDVP) were not significantly different for the five locations. Captures with the Mallet TMR dispenser without DDVP and Vaportape were similar to those for Mallet TMR with DDVP, although there were some slight location differences. In conclusion, based on these results, the Mallet TMR dispenser could potentially be used in California habitats where large numbers of detection traps are currently deployed. Use of Vaportape with dispensers would not require them to be registered with US Environmental Protection Agency (EPA). Dispensers for use as Male Annihilation Technique (MAT) devices will be tested further in Hawaii.

An Overview of Pest Species of Bactrocera Fruit Flies (Diptera: Tephritidae) and the Integration of Biopesticides with Other Biological Approaches for Their Management with a Focus on the Pacific Region.

Fruit flies (Diptera: Tephritidae) are among the most economically important pest species in the world, attacking a wide range of fruits and fleshy vegetables throughout tropical and sub-tropical areas. These species are such devastating crop pests that major control and eradication programs have been developed in various parts of the world to combat them. The array of control methods includes insecticide sprays to foliage and soil, bait-sprays, male annihilation techniques, releases of sterilized flies and parasitoids, and cultural controls. During the twenty first century there has been a trend to move away from control with organophosphate insecticides (e.g., malathion, diazinon, and naled) and towards reduced risk insecticide treatments. In this article we present an overview of 73 pest species in the genus Bactrocera, examine recent developments of reduced risk technologies for their control and explore Integrated Pest Management (IPM) Programs that integrate multiple components to manage these pests in tropical and sub-tropical areas.

Ammonium Acetate Enhances the Attractiveness of a Variety of Protein-Based Baits to Female Ceratitis capitata (Diptera: Tephritidae).

Ammonia and its derivatives are used by female fruit flies (Diptera: Tephritidae) as volatile cues to locate protein-rich food needed to produce their eggs. This need for external protein sources has led to the development of behaviorally based control strategies such as food-based lures and insecticidal baits targeting pestiferous fruit fly species. In field cage studies conducted in Hawaii, we examined the behavioral response of laboratory-reared male and female Mediterranean fruit fly, Ceratitis capitata (Wiedemann), to seven commercially available protein baits and to beer waste, a relatively inexpensive and readily available substance. Each material was tested alone or in combination with either ammonium acetate or ammonium carbonate. For the majority of baits evaluated, the presence of ammonium acetate, but not ammonium carbonate, elicited a significantly greater level of response of female C. capitata compared with the protein baits alone. The addition of ammonium acetate to selected baits increased bait attractiveness to a level comparable with that elicited by the most widely used spinosad-based protein bait, GF-120. Our findings indicate that the addition of ammonium acetate to commercially available proteinaceous baits and to beer waste can greatly improve their attractiveness to C. capitata, potentially increasing the bait's effectiveness for fruit fly monitoring and suppression.

Weathering and Chemical Degradation of Methyl Eugenol and Raspberry Ketone Solid Dispensers for Detection, Monitoring, and Male Annihilation of Bactrocera dorsalis and Bactrocera cucurbitae (Diptera: Tephritidae) in Hawaii.

Solid male lure dispensers containing methyl eugenol (ME) and raspberry ketone (RK), or mixtures of the lures (ME + RK), and dimethyl dichloro-vinyl phosphate (DDVP) were evaluated in area-wide pest management bucket or Jackson traps in commercial papaya (Carica papaya L.) orchards where both oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillett), are pests. Captures of B. dorsalis with fresh wafers in Jackson and bucket traps were significantly higher on the basis of ME concentration (Mallet ME [56%] > Mallet MR [31.2%] > Mallet MC [23.1%]). Captures of B. cucurbitae with fresh wafers in Jackson and bucket traps were not different regardless of concentration of RK (Mallet BR [20.1%] = Mallet MR [18.3%] = Mallet MC [15.9%]). Captures of B. dorsalis with fresh wafers, compared with weathered wafers, were significantly different after week 12; captures of B. cucurbitae were not significantly different after 16 wk. Chemical analyses revealed presence of RK in dispensers in constant amounts throughout the 16-wk trial. Degradation of both ME and DDVP over time was predicted with a high level of confidence by nonlinear asymptotic exponential decay curves. Results provide supportive data to deploy solid ME and RK wafers (with DDVP) in fruit fly traps for detection programs, as is the current practice with solid TML dispensers placed in Jackson traps. Wafers with ME and RK might be used in place of two separate traps for detection of both ME and RK responding fruit flies and could potentially reduce cost of materials and labor by 50%.

Incorporating variability in point estimates in risk assessment: Bridging the gap between LC50 and population endpoints.

Historically, point estimates such as the median lethal concentration (LC50) have been instrumental in assessing risks associated with toxicants to rare or economically important species. In recent years, growing awareness of the shortcomings of this approach has led to an increased focus on analyses using population endpoints. However, risk assessment of pesticides still relies heavily on large amounts of LC50 data amassed over decades in the laboratory. Despite the fact that these data are generally well replicated, little or no attention has been given to the sometime high levels of variability associated with the generation of point estimates. This is especially important in agroecosystems where arthropod predator-prey interactions are often disrupted by the use of pesticides. Using laboratory derived data of 4 economically important species (2 fruit fly pest species and 2 braconid parasitoid species) and matrix based population models, the authors demonstrate in the present study a method for bridging traditional point estimate risk assessments with population outcomes. The results illustrate that even closely related species can show strikingly divergent responses to the same exposures to pesticides. Furthermore, the authors show that using different values within the 95% confidence intervals of LC50 values can result in very different population outcomes, ranging from quick recovery to extinction for both pest and parasitoid species. The authors discuss the implications of these results and emphasize the need to incorporate variability and uncertainty in point estimates for use in risk assessment.

Attraction and mortality of Bactrocera dorsalis (Diptera: Tephritidae) to STATIC Spinosad ME weathered under operational conditions in California and Florida: a reduced-risk male annihilation treatment.

Studies were conducted in 2013-2014 to quantify attraction, feeding, and mortality of male oriental fruit flies, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), to STATIC Spinosad ME a reduced-risk male annihilation treatment (MAT) formulation consisting of an amorphous polymer matrix in combination with methyl eugenol (ME) and spinosad compared with the standard treatment of Min-U-Gel mixed with ME and naled (Dibrom). Our approach used a behavioral methodology for evaluation of slow-acting reduced-risk insecticides. ME treatments were weathered for 1, 7, 14, 21, and 28 d under operational conditions in California and Florida and shipped to Hawaii for bioassays. In field tests using bucket traps to attract and capture wild males, and in toxicity studies conducted in 1-m(3) cages using released males of controlled ages, STATIC Spinosad ME performed equally as well to the standard formulation of Min-U-Gel ME with naled for material aged up to 28 d in both California and Florida. In laboratory feeding tests in which individual males were exposed for 5 min to the different ME treatments, mortality induced by STATIC Spinosad ME recorded at 24 h did not differ from mortality caused by Min-U-Gel ME with naled at 1, 7, 14, and 21 d in California and was equal to or higher for all weathered time periods in Florida during two trials. Spinosad has low contact toxicity, and when mixed with an attractant and slow release matrix, offers a reduced-risk alternative for eradication of B. dorsalis and related ME attracted species, without many of the potential negative effects to humans and nontargets associated with broad-spectrum contact insecticides such as naled.

Deconstructing the surrogate species concept: a life history approach to the protection of ecosystem services.

The use of the surrogate species concept is widespread in environmental risk assessment and in efforts to protect species that provide ecosystem services, yet there are no standard protocols for the choice of surrogates. Surrogates are often chosen on the basis of convenience or vague resemblances in physiology or life history to species of concern. Furthermore, our ability to predict how species of concern will fare when subjected to disturbances such as environmental contaminants or toxicants is often based on woefully misleading comparisons of static toxicity tests. Here we present an alternative approach that features a simple mathematical model parameterized with life history data applied to an assemblage of species that provide an important ecosystem service: a suite of parasitoid wasps that provide biological control of agricultural pests. Our results indicate that these parasitoid wasp species have different population responses to toxic insult--that is, we cannot predict how all four species will react to pesticide exposure simply by extrapolating from the response of any one species. Furthermore, sensitivity analysis of survivorship and reproduction demonstrates that the life stage most sensitive to pesticide disturbance varies among species. Taken together, our results suggest that the ability to predict the fate of a suite of species using the response of just one species (the surrogate species concept) is widely variable and potentially misleading.

Spatial dynamics of two oriental fruit fly (Diptera: Tephritidae) parasitoids, Fopius arisanus and Diachasmimorpha longicaudata (Hymenoptera: Braconidae), in a Guava orchard in Hawaii.

We examined spatial patterns of both sexes of oriental fruit fly, Bactrocera dorsalis (Hendel), and its two most abundant parasitoids, Fopius arisanus (Sonan) and Diachasmimorpha longicaudata (Ashmead) in a commercial guava (Psidium guajava L.) orchard. Oriental fruit fly spatial patterns were initially random, but became highly aggregated with host fruit ripening and the subsequent colonization of, first, F. arisanus (egg-pupal parasitoid) and, second, D. longicaudata (larval-pupal parasitoid). There was a significant positive relationship between populations of oriental fruit fly and F. arisanus during each of the F. arisanus increases, a pattern not exhibited between oriental fruit fly and D. longicaudata. Generally, highest total numbers of males and females (oriental fruit fly, F. arisanus, and D. longicaudata) occurred on or about the same date. There was a significant positive correlation between male and female populations of all three species; we measured a lag of 2-4 wk between increases of female F. arisanus and conspecific males. There was a similar trend in one of the two years for the second most abundant species, D. longicaudata, but no sign of a time lag between the sexes for oriental fruit fly. Spatially, we found a significant positive relationship between numbers of F. arisanus in blocks and the average number in adjoining blocks. We did not find the same effect for oriental fruit fly and D. longicaudata, possibly a result of lower overall numbers of the latter two species or less movement of F. arisanus within the field.

Leg impairment magnifies reproductive costs in male Mediterranean fruit flies, Ceratitis capitata.

Injuries frequently accumulate with age in nature. Despite the commonality of injury and the resulting impairment, there are limited experimental data for the effects of impairment on life history trade-offs between reproduction and survival in insects. We tested the effects of artificial injury and the resulting impairment on the reproductive costs and behavior of male medflies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Treatment flies were impaired by amputating tarsomere segments 2-5 from the right foreleg at either eclosion or age 22 days. The effect of impairment and age on the cost of reproduction was tested by varying the timing of female availability among the treatments. Courtship behavior and copulation rates were observed hourly from age 2-5 days to determine the effects of impairment on reproductive behavior. Female access combined with the impairment reduced the life expectancy of males more than the impairment alone, whereas the health effect of amputation was influenced by age. Conversely, the risk of death due to impairment was not influenced by the males' mating status prior to amputation. The males' copulation success was reduced due to impairment, whereas courtship behavior was not affected. Impairment does not reduce the males' impulse to mate but decreases the females' receptivity to copulation, while also increasing the cost of each successful mating. Overall, minor impairment lowers the reproductive success of males and reduces longevity.

Effects of diet and host access on fecundity and lifespan in two fruit fly species with different life history patterns.

The reproductive ability of female tephritids can be limited and prevented by denying access to host plants and restricting the dietary precursors of vitellogenesis. The mechanisms underlying the delayed egg production in each case are initiated by different physiological processes that are anticipated to have dissimilar effects on lifespan and reproductive ability later in life. The egg laying abilities of laboratory reared females of the Mediterranean fruit fly (Ceratitis capitata Wiedmann) and melon fly (Bactrocera cucurbitae Coquillett) from Hawaii are delayed or suppressed by limiting access to host fruits and dietary protein. In each case, this is expected to prevent the loss of lifespan associated with reproduction until protein or hosts are introduced. Two trends are observed in each species: Firstly, access to protein at eclosion leads to a greater probability of survival and higher reproductive ability than if it is delayed, and secondly, that delayed host access reduces lifetime reproductive ability without improving life expectancy. When host access and protein availability are delayed, the rate of reproductive senescence is reduced in the medfly, whereas the rate of reproductive senescence is generally increased in the melon fly. Overall, delaying reproduction lowers the fitness of females by constraining their fecundity for the remainder of the lifespan without extending the lifespan.

Field trials of solid triple lure (trimedlure, methyl eugenol, raspberry ketone, and DDVP) dispensers for detection and male annihilation of Ceratitis capitata, Bactrocera dorsalis, and Bactrocera cucurbitae (Diptera: Tephritidae) in Hawaii.

Solid Mallet TMR (trimedlure [TML], methyl eugenol [ME], raspberry ketone [RK]) wafers and Mallet CMR (ceralure, ME, RK, benzyl acetate) wafers impregnated with DDVP (2,2-dichlorovinyl dimethyl phosphate) insecticide were measured in traps as potential detection and male annihilation technique (MAT) devices. Comparisons were made with 1) liquid lure and insecticide formulations, 2) solid cones and plugs with an insecticidal strip, and 3) solid single and double lure wafers with DDVP for captures of Mediterranean fruit fly, Ceratitis capitata (Wiedemann); oriental fruit fly, Bactrocera dorsalis Hendel; and melon fly, B. cucurbitae Coquillett. Bucket and Jackson traps were tested in a coffee plantation near Eleele, Kauai Island, HI (trials at high populations) and avocado orchards near Kona, HI Island, HI (trials at low populations). Captures of all three species with Mallet TMR were not different from Mallet CMR; therefore, subsequent experiments did not include Mallet CMR because of higher production costs. In MAT trials near Eleele, HI captures in AWPM traps with Mallet TMR wafers were equal to any other solid lure (single or double) except the Mallet ME wafer. In survey trials near Kona, captures of C. capitata, B. cucurbitae, and B. dorsalis with Mallet TMR wafers were equal to those for the standard TML, ME, and C-L traps used in FL and CA. A solid Mallet TMR wafer is safer, more convenient to handle, and may be used in place of several individual lure and trap systems, potentially reducing costs of large survey and detection programs in Florida and California, and MAT programs in Hawaii.