Icerya Purchasi

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Charlotte E. Causton - One of the best experts on this subject based on the ideXlab platform.

  • post release evaluation of rodolia cardinalis coleoptera coccinellidae for control of Icerya Purchasi hemiptera monophlebidae in the galapagos islands
    Biological Control, 2013
    Co-Authors: Mark S Hoddle, Roy Driesche, Christina D Hoddle, M P Lincango, Claudio Crespo Ramirez, Jose Loayza, Charlotte E. Causton
    Abstract:

    Abstract Post-release field evaluations (2009–2011) of the impacts of Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae) released in the Galapagos Islands in 2002 for the classical biological control of Icerya Purchasi Maskell (Hemiptera: Monophlebidae) indicated that substantial (∼60–98% reduction in I. Purchasi densities) and persistent suppression of this pest has occurred. Most endemic and native plants surveyed appear to no longer have heavy I. Purchasi infestations nor disfiguring honeydew contamination. However, pest suppression by R. cardinalis was less successful on some plant species, such as the native sand dune-inhabiting Scaevola plumieri (L.) Vahl. on which substantial, but fluctuating I. Purchasi densities remain. In urban areas, invasive ant species tending I. Purchasi colonies likely interfered with biological control. In 22 h of field cage observations of R. cardinalis foraging on native plants infested with various combinations of five non-target arthropod species and I. Purchasi, no attacks on non-target prey occurred. In field cages, all observed attacks and feeding activity were on I. Purchasi. Captures of R. cardinalis were significantly higher on yellow sticky traps placed in plants infested with I. Purchasi compared to plants that were not hosts of I. Purchasi. We conclude that the first biological control project in the Galapagos Islands with R. cardinalis against I. Purchasi has been very successful and R. cardinalis is highly unlikely to affect non-target species following its establishment and spread in the archipelago.

  • Monitoring the effects of Rodolia cardinalis on Icerya Purchasi populations on the Galapagos Islands
    BioControl, 2012
    Co-Authors: Carolina Calderón Alvarez, Charlotte E. Causton, Roy Driesche, Christina D Hoddle, Mark S Hoddle, Edward J Stanek
    Abstract:

    In January 2002, the first biological control program was implemented on the Galapagos Islands with the release of the Australian coccinellid Rodolia cardinalis Mulsant to control the invasive cottony cushion scale, Icerya Purchasi Maskell . This was the first time that Galapagos authorities had approved the introduction of a biological control agent to this iconic archipelago and, because of this precedent, it was important to monitor and evaluate its behaviour soon after its introduction. Surveys were carried out after the release of R. cardinalis in 2002 to confirm establishment on Santa Cruz Island. In 2009, seven years post-release, a broader survey was done to document spread throughout the archipelago . Directly after the release of R . cardinalis in 2002 , a predator exclusion study and field observations were carried out on scale insect populations on white mangrove ( Laguncularia racemosa [L.] Gaertn. F.) on Santa Cruz Island to document impact. In less than three months after R . cardinalis was released in 2002, populations of I. Purchasi on white mangrove that were exposed to the predator in the exclusion experiment, or were monitored in the field, had declined by 99–100%. Results suggest that R . cardinalis played a key role in this decline, possibly in combination with high rainfall . Rodolia cardinalis dispersed quickly after its release and by 2009 was found in a wide variety of habitats on seven of the eight islands surveyed that had records of I . Purchasi . Two of these were self-introductions. Further monitoring is recommended to determine whether this biological control agent has successfully reduced scale insect numbers on other valued plant species.

  • evaluating the safety of rodolia cardinalis to two species of galapagos finch camarhynchus parvulus and geospiza fuliginosa
    Biological Control, 2011
    Co-Authors: M P Lincango, Charlotte E. Causton, Calderon C Alvarez, Gustavo Jimenezuzcategui
    Abstract:

    Abstract Some species of coccinellids exude a fluid that contains an alkaloid which can be toxic to vertebrates that ingest them. Because of this, before introducing Rodolia cardinalis to the Galapagos Islands as a biological control agent for the invasive scale insect, Icerya Purchasi , it was considered necessary to determine whether it is toxic to birds. In this study, experiments were carried out with two common, insectivorous finches that are endemic to the Galapagos Islands; Camarhynchus parvulus (12 individuals) and Geospiza fuliginosa (16 individuals). Finches were maintained in captivity for 12–18 days. This period was divided into three phases: adaptation, experimental, and observation. During the experimental phase, test individuals, in addition to their regular diet, were fed 0.15 g portions of larvae or adults of R. cardinalis on alternate days over four days. The control group were fed 0.15 g of Asciodes quietalis abdomens in place of R. cardinalis . Symptoms of toxicity (mortality, deterioration, critical weight loss) from feeding on R. cardinalis were not observed in either species while in captivity, but birds avoided or rejected beetles indicating that they were distasteful. Finches regurgitated a higher number of larvae than adult beetles suggesting that larvae were less palatable than adults. Although long-term monitoring was not possible, results suggest that at least two species of finch will be unaffected by the release of R. cardinalis into the Galapagos Islands.

  • feeding range studies of rodolia cardinalis mulsant a candidate biological control agent of Icerya Purchasi maskell in the galapagos islands
    Biological Control, 2004
    Co-Authors: Charlotte E. Causton, M P Lincango, Thomas G A Poulsom
    Abstract:

    The immediate threat of the cottony cushion scale, Icerya Purchasi Maskell (Homoptera: Margarodidae), to the conservation of endangered flora in the Galapagos islands prompted conservation groups to assess the risks associated with the introduction of its natural enemy, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae). Although R. cardinalis has been widely used for controlling this exotic pest, little information was found to confirm its presumed narrow feeding range. Consequently, studies were deemed necessary to determine whether the introduction of R. cardinalis would harm the island’s native invertebrate fauna, in particular rare or threatened species. Using no-choice trials, we tested neonate and third instar larvae of R. cardinalis against 16 and 11 potential prey species, respectively. Adults with prior feeding experience on I. Purchasi were tested against eight non-target species and naive adults (those that had not fed on I. Purchasi) were tested against six. These trials included up to 35% of the Homoptera species of conservation value presumed to have the highest risk of being preyed upon by R. cardinalis. To maximize the range of species exposed to R. cardinalis, feeding trials were also carried out with some introduced species representative of groups containing potential non-target species that were not located for testing. R. cardinalis was unable to complete its life cycle on any of the test prey species and only fed on Margarodes similis Morrison (Homoptera: Margarodidae), a species closely related to the cottony cushion scale. M. similis, however, is subterranean and in its natural habitat is not at risk from foraging by R. cardinalis. Based on these trials, we believe that immature stages of R. cardinalis will have no impact on the non-target invertebrate fauna of the Galapagos islands because they specialize on Margarodidae. Although the limited nature of our testing prevents us from reaching a definitive conclusion about the prey range of R. cardinalis adults, our results indicate that it is also narrow. According to our field and laboratory studies, niche overlap with native predators of Homoptera will be minimal and intraguild predation should not occur.

M P Lincango - One of the best experts on this subject based on the ideXlab platform.

  • post release evaluation of rodolia cardinalis coleoptera coccinellidae for control of Icerya Purchasi hemiptera monophlebidae in the galapagos islands
    Biological Control, 2013
    Co-Authors: Mark S Hoddle, Roy Driesche, Christina D Hoddle, M P Lincango, Claudio Crespo Ramirez, Jose Loayza, Charlotte E. Causton
    Abstract:

    Abstract Post-release field evaluations (2009–2011) of the impacts of Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae) released in the Galapagos Islands in 2002 for the classical biological control of Icerya Purchasi Maskell (Hemiptera: Monophlebidae) indicated that substantial (∼60–98% reduction in I. Purchasi densities) and persistent suppression of this pest has occurred. Most endemic and native plants surveyed appear to no longer have heavy I. Purchasi infestations nor disfiguring honeydew contamination. However, pest suppression by R. cardinalis was less successful on some plant species, such as the native sand dune-inhabiting Scaevola plumieri (L.) Vahl. on which substantial, but fluctuating I. Purchasi densities remain. In urban areas, invasive ant species tending I. Purchasi colonies likely interfered with biological control. In 22 h of field cage observations of R. cardinalis foraging on native plants infested with various combinations of five non-target arthropod species and I. Purchasi, no attacks on non-target prey occurred. In field cages, all observed attacks and feeding activity were on I. Purchasi. Captures of R. cardinalis were significantly higher on yellow sticky traps placed in plants infested with I. Purchasi compared to plants that were not hosts of I. Purchasi. We conclude that the first biological control project in the Galapagos Islands with R. cardinalis against I. Purchasi has been very successful and R. cardinalis is highly unlikely to affect non-target species following its establishment and spread in the archipelago.

  • evaluating the safety of rodolia cardinalis to two species of galapagos finch camarhynchus parvulus and geospiza fuliginosa
    Biological Control, 2011
    Co-Authors: M P Lincango, Charlotte E. Causton, Calderon C Alvarez, Gustavo Jimenezuzcategui
    Abstract:

    Abstract Some species of coccinellids exude a fluid that contains an alkaloid which can be toxic to vertebrates that ingest them. Because of this, before introducing Rodolia cardinalis to the Galapagos Islands as a biological control agent for the invasive scale insect, Icerya Purchasi , it was considered necessary to determine whether it is toxic to birds. In this study, experiments were carried out with two common, insectivorous finches that are endemic to the Galapagos Islands; Camarhynchus parvulus (12 individuals) and Geospiza fuliginosa (16 individuals). Finches were maintained in captivity for 12–18 days. This period was divided into three phases: adaptation, experimental, and observation. During the experimental phase, test individuals, in addition to their regular diet, were fed 0.15 g portions of larvae or adults of R. cardinalis on alternate days over four days. The control group were fed 0.15 g of Asciodes quietalis abdomens in place of R. cardinalis . Symptoms of toxicity (mortality, deterioration, critical weight loss) from feeding on R. cardinalis were not observed in either species while in captivity, but birds avoided or rejected beetles indicating that they were distasteful. Finches regurgitated a higher number of larvae than adult beetles suggesting that larvae were less palatable than adults. Although long-term monitoring was not possible, results suggest that at least two species of finch will be unaffected by the release of R. cardinalis into the Galapagos Islands.

  • feeding range studies of rodolia cardinalis mulsant a candidate biological control agent of Icerya Purchasi maskell in the galapagos islands
    Biological Control, 2004
    Co-Authors: Charlotte E. Causton, M P Lincango, Thomas G A Poulsom
    Abstract:

    The immediate threat of the cottony cushion scale, Icerya Purchasi Maskell (Homoptera: Margarodidae), to the conservation of endangered flora in the Galapagos islands prompted conservation groups to assess the risks associated with the introduction of its natural enemy, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae). Although R. cardinalis has been widely used for controlling this exotic pest, little information was found to confirm its presumed narrow feeding range. Consequently, studies were deemed necessary to determine whether the introduction of R. cardinalis would harm the island’s native invertebrate fauna, in particular rare or threatened species. Using no-choice trials, we tested neonate and third instar larvae of R. cardinalis against 16 and 11 potential prey species, respectively. Adults with prior feeding experience on I. Purchasi were tested against eight non-target species and naive adults (those that had not fed on I. Purchasi) were tested against six. These trials included up to 35% of the Homoptera species of conservation value presumed to have the highest risk of being preyed upon by R. cardinalis. To maximize the range of species exposed to R. cardinalis, feeding trials were also carried out with some introduced species representative of groups containing potential non-target species that were not located for testing. R. cardinalis was unable to complete its life cycle on any of the test prey species and only fed on Margarodes similis Morrison (Homoptera: Margarodidae), a species closely related to the cottony cushion scale. M. similis, however, is subterranean and in its natural habitat is not at risk from foraging by R. cardinalis. Based on these trials, we believe that immature stages of R. cardinalis will have no impact on the non-target invertebrate fauna of the Galapagos islands because they specialize on Margarodidae. Although the limited nature of our testing prevents us from reaching a definitive conclusion about the prey range of R. cardinalis adults, our results indicate that it is also narrow. According to our field and laboratory studies, niche overlap with native predators of Homoptera will be minimal and intraguild predation should not occur.

Elizabeth E. Grafton-cardwell - One of the best experts on this subject based on the ideXlab platform.

  • Arthropod Infestation Levels on Mandarins in California.
    Journal of economic entomology, 2020
    Co-Authors: Bodil N. Cass, Elizabeth E. Grafton-cardwell, Lindsey M Hack, Tobias G Mueller, Darian Buckman, Jay A. Rosenheim
    Abstract:

    Integrated pest management (IPM) guidelines for horticulture are typically established from years of experimental research and experience for a crop species. Ecoinformatics methods can help to quickly adapt these guidelines following major changes in growing practices. Citrus production in California is facing several major challenges, one of which is a shift away from sweet oranges [Citrus sinensis (L.) Osbeck Sapindales: Rutaceae] toward mandarins (including mostly cultivars of C. reticulata Blanco and C. clementina hort. ex Tanaka). In the absence of IPM guidelines for mandarins, growers are relying on pest information developed from oranges. We mined a database of management records from commercial growers and consultants to determine densities for four arthropod pests: cottony cushion scale (Icerya Purchasi Maskell Hemiptera: Monophlebidae), citricola scale (Coccus pseudomagnoliarum Kuwana Hemiptera: Coccidae), European earwig (Forficula auricularia Linnaeus Dermaptera: Forficulidae), citrus red mite (Panonychus citri McGregor Acari: Tetranychidae), and a natural enemy, predatory mites in the genus Euseius (Congdon Acarina: Phytoseiidae). Densities of cottony cushion scale were approximately 10-40 times higher in the two most commonly grown mandarin species than in sweet oranges, suggesting this pest is reaching outbreak levels more often on mandarins. Densities of the other pests and predatory mites did not differ significantly across citrus species. This is a first step toward establishing IPM guidelines for mandarins for these pests; more research is needed to determine how arthropod densities relate to crop performance in mandarins.

  • Food Suitability and Population Dynamics of Lorryia formosa (Acari: Tydeidae)
    Environmental entomology, 2018
    Co-Authors: S G Gautam, Yuling Ouyang, Elizabeth E. Grafton-cardwell
    Abstract:

    Lorryia formosa Cooreman (Acari: Tydeidae) is a species of mite commonly associated with citrus in many countries including the United States. A survey report in 1957 suggested phytophagous nature, while other studies claimed that L. formosa populations are associated with honeydew producing insects and sooty mold and it acts as a sanitizing agent. We investigated the effect of various diets on the survival and progeny production of L. formosa on excised leaves and the survival and potential to cause feeding damage to leaves of potted plants in a greenhouse study. A 2-yr field survey of a mandarin orchard was also conducted to elucidate the seasonal infestation, damage potential and population structure of L. formosa in a natural habitat. Results showed that all L. formosa adults and immatures died in less than 14 d on excised leaves, did not survive beyond 7 d on potted citrus plants alone, and caused no observable feeding damage to leaves or fruit. When sugar water, honeydew, or cottony cushion scale, Icerya Purchasi Maskell (Hemiptera: Margarodidae), was present, adults and immatures survived the duration of the experiments and produced additional generations. The field survey showed that all stages of L. formosa were present in a mandarin orchard throughout the year and insecticide applications affected but did not eliminate mite populations. Fruit generally had a greater percentage infestation of mites (44.8 ± 4.0) than leaves (16.0 ± 4.7). These studies confirmed that L. formosa cannot sustain a population on leaf tissue alone and is nondamaging to citrus in California.

  • Role of Imidacloprid in Integrated Pest Management of California Citrus
    Journal of economic entomology, 2008
    Co-Authors: Elizabeth E. Grafton-cardwell, J. E. Lee, S. M. Robillard, J. M. Gorden
    Abstract:

    Portions of three commercial citrus orchards were treated for 1 yr with foliar imidacloprid or for 2 yr with a systemic formulation in a replicated plot design to determine the impact of this neonicotinoid on the San Joaquin Valley California citrus integrated pest management (IPM) program. Foliar-applied imidacloprid had little effect on California red scale, Aonidiella aurantii (Maskell); cottony cushion scale, Icerya Purchasi Maskell; or citrus red mite, Panonychus citri (McGregor), populations. Short-term suppression of the parasitoids Aphytis melinus DeBach and Comperiella bifasciata Howard; vedalia, Rodolia cardinalis (Mulsant); and the predacious mite Euseius tularensis (Congdon) were observed. Suppression of natural enemies allowed scales and mites to maintain higher populations in the treated areas compared with the nontreated areas. Thus, foliar imidacloprid did not exhibit control of these citrus pest species, and it disrupted biological control. Systemically applied imidacloprid suppressed California red scale and citricola scale populations 2–3 mo after treatment. Suppression of parasitoids of the California red scale also was observed. Thus, treatments of systemic imidacloprid applied in areawide management programs for invasive pests would provide a benefit of California red scale and citricola scale suppression. However, this treatment provided only single-season control of citricola scale, it was somewhat disruptive of biological control, and it did not suppress densities of either scale as low as a treatment of the organophosphate chlorpyrifos for citricola scale or the insect growth regulator pyriproxyfen for California red scale. Insecticides with longer periods of efficacy and greater IPM compatibility than imidacloprid should be used for a sustainable IPM approach in California citrus.

  • Effects of temperature on development of vedalia beetle, Rodolia cardinalis (Mulsant)
    Biological Control, 2005
    Co-Authors: Elizabeth E. Grafton-cardwell, Gregory H. Montez
    Abstract:

    Abstract The effect of temperature on the development of the vedalia beetle, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae), fed Icerya Purchasi Maskell (Homoptera: Margarodidae) under controlled laboratory conditions was studied. Adults exposed to temperatures of 25, 28, 31, 34, and 37 °C for 72 h showed 95–100% survival, however egg production was significantly reduced at 34 and 37 °C. In addition, eggs maintained at 34 °C showed reduced hatch and survival of larvae, and eggs held at 37 °C failed to hatch. The duration of each developmental stage and survival of each stage were measured at 10, 14, 18, 22, and 25 °C. There was no egg eclosion at 10 °C. The developmental time from egg to adult emergence decreased from 79 to 18 days for temperatures from 14 to 25 °C. The sex ratio was unaffected by these temperatures. The lower developmental temperature threshold of R. cardinalis was estimated to be 10.8 °C and the degree–day accumulation was calculated as 279 for development from egg to adult eclosion. These results will guide further research designed to optimize management of vedalia populations in the San Joaquin Valley of California.

  • Conserving Vedalia Beetle, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae), in Citrus: A Continuing Challenge as New Insecticides Gain Registration
    Journal of economic entomology, 2003
    Co-Authors: Elizabeth E. Grafton-cardwell
    Abstract:

    The effects of insecticides used for California citrus pest management were evaluated using larval and adult stages of vedalia beetle, Rodolia cardinalis (Mulsant). This predatory beetle is essential for control of cottony cushion scale Icerya Purchasi (Williston) (Homoptera: Margarodidae) in San Joaquin Valley citrus. When adult beetles were exposed to treated citrus leaves, adult survival was significantly reduced by the foliar neonicotinoid imidacloprid and the pyrethroid cyfluthrin. Progeny production was significantly reduced by imidacloprid, cyfluthrin, fenpropathrin, and buprofezin. Buprofezin, pyriproxifen, and foliar imidacloprid also significantly reduced successful development of larvae into the adult stage. When vedalia stages were fed insecticide-treated cottony cushion scale reared on Pittosporum tobira (Thunb.) Ait, toxic effects were more severe than contact toxicity alone. Adult beetle survival was most profoundly reduced by the pyrethroids and to a lesser extent the foliar neonicotinoids acetamiprid and imidacloprid. Progeny production and larval development to adulthood were reduced by all insecticides but were most severely affected by pyriproxifen and the pyrethroids. Systemically applied neonicotinoids were toxic to vedalia larvae feeding on cottony cushion scale that had ingested these insecticides. These data demonstrate that IGRs, neonicotinoid insecticides, and pyrethroid insecticides have a significant, negative impact on vedalia beetles. Depending on the rate of insecticide used, the number and timing of applications, and the level of coverage of the tree, disruption of vedalia can be minimized. However, the situation is made difficult when pests such as citrus thrips Scirtothrips citri (Moulton) (Thysanoptera: Thripidae), forktailed bush katydid Scuddaria furcata Brunner von Wattenwyl (Orthoptera: Tettigoiniidae), or glassy-winged sharpshooter Homalodisca coagulata Say (Homoptera: Cicadellidae) require these pesticide treatments during periods of vedalia beetle activity.

D Blumberg - One of the best experts on this subject based on the ideXlab platform.

  • Biological control of four homopterans in Israeli horticulture: achievements and problems
    Phytoparasitica, 1992
    Co-Authors: Z. Mendel, D Blumberg, M. Wysoki
    Abstract:

    Biological control of four phloem-feeding homopterans on citrus and avocado is discussed. Examples of successful control are those achieved with Parabemisia myricae and Icerya Purchasi ; only partial control was obtained with Protopulvinaria pyriformis (nonspecific parasitoid complex) and with Planococcus citri (climatic conditions unfavourable for its natural enemies).

  • colonization trials with cryptochetum Iceryae and rodolia Iceryae for improved biological control of Icerya Purchasi in israel
    Biological Control, 1991
    Co-Authors: Zvi Mendel, D Blumberg
    Abstract:

    Abstract Colonization of additional natural enemies of Icerya Purchasi Maskell (Homoptera: Margarodidae) in Israel was considered because of the frequent outbreaks of the scale during the 1980s and the chronic severe injuries to certain ornamental plants whose toxic effects through the scale reduce the effectiveness of Rodolia cardinalis Mulsant (Coleoptera: Coccinellidae). Colonization trials were conducted with the parasitic fly Cryptochetum Iceryae Williston (Diptera: Cryptochetidae) collected in southern California and with Rodolia Iceryae Jenson sent from South Africa. Rearing experiments of both natural enemies were conducted using I. Purchasi and I. aegyptiaca (Douglas) infesting different plant species. C. Iceryae developed on I. Purchasi growing on 17 host plant species. I. aegyptiaca was not affected by the fly. R. Iceryae could not complete its development on either I. Purchasi or I. aegyptiaca. C. Iceryae was released at nine sites planted with Erythrina corallodendrum, Spartium junceum, or Retama raetam infested with I. Purchasi. In citrus groves, after 2 years and following several releases, it is still uncertain whether C. Iceryae has become established. C. Iceryae was acclimatized at all sites planted with E. corallodendrum, S. junceum, and R. raetam and suppression of the scale was achieved in 2 years, probably because of the lack of significant competition with Rodolia cardinalis. I. Purchasi populations were very sparse in the sampled citrus groves. Only in one site did we observe a rapid switch from the latent epidemic phase. This outbreak resulted in serious damage to the trees and was followed by a rapid breakdown of the scale population due to a sharp increase in the R. cardinalis population.

  • Effect of Buprofezin onIcerya Purchasi andPlanococcus Citri
    Phytoparasitica, 1991
    Co-Authors: Zvi Mendel, D Blumberg, Isaac Ishaaya
    Abstract:

    The effectiveness of buprofezin (aqueous suspensions from 25% wettable powder) on cumulative nymph mortality and reproduction of two homopterous pests, Icerya Purchasi Maskell (Margarodidae) and Planococcus citri (Risso) (Pseudococcidae), was investigated under laboratory conditions. Buprofezin was very effective against crawlers of both species. Dipping in concentrations of 0.002%, 0.01% and 0.05% (a. i.) resulted in 91–99% nymph mortality of P. citri , whereas 100% mortality was recorded when I. Purchasi was treated at 0.05% (a. i.); the 3rd-instar nymphs of I. Purchasi were less susceptible to the chemical. Death of the larval stages occurred mainly during the molting process to the 2nd-instar nymphs. At 0.05%, buprofezin sprayed on adults slightly reduced fecundity and decreased egg hatch to 31% for I. Purchasi and, depending on the exposure period of the females, to 49-7% for P. citri. Buprofezin at 0.05% exhibited strong ovicidal activity on P. citri , resulting in inhibition of over 80% egg hatch.

Gustavo Jimenezuzcategui - One of the best experts on this subject based on the ideXlab platform.

  • evaluating the safety of rodolia cardinalis to two species of galapagos finch camarhynchus parvulus and geospiza fuliginosa
    Biological Control, 2011
    Co-Authors: M P Lincango, Charlotte E. Causton, Calderon C Alvarez, Gustavo Jimenezuzcategui
    Abstract:

    Abstract Some species of coccinellids exude a fluid that contains an alkaloid which can be toxic to vertebrates that ingest them. Because of this, before introducing Rodolia cardinalis to the Galapagos Islands as a biological control agent for the invasive scale insect, Icerya Purchasi , it was considered necessary to determine whether it is toxic to birds. In this study, experiments were carried out with two common, insectivorous finches that are endemic to the Galapagos Islands; Camarhynchus parvulus (12 individuals) and Geospiza fuliginosa (16 individuals). Finches were maintained in captivity for 12–18 days. This period was divided into three phases: adaptation, experimental, and observation. During the experimental phase, test individuals, in addition to their regular diet, were fed 0.15 g portions of larvae or adults of R. cardinalis on alternate days over four days. The control group were fed 0.15 g of Asciodes quietalis abdomens in place of R. cardinalis . Symptoms of toxicity (mortality, deterioration, critical weight loss) from feeding on R. cardinalis were not observed in either species while in captivity, but birds avoided or rejected beetles indicating that they were distasteful. Finches regurgitated a higher number of larvae than adult beetles suggesting that larvae were less palatable than adults. Although long-term monitoring was not possible, results suggest that at least two species of finch will be unaffected by the release of R. cardinalis into the Galapagos Islands.