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Peter M. J. Brown - One of the best experts on this subject based on the ideXlab platform.
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In the shadow of the condor: invasive Harmonia axyridis found at very high altitude in the Chilean Andes
Insect Conservation and Diversity, 2017Co-Authors: Audrey A. Grez, Helen E. Roy, Tania Zaviezo, Peter M. J. Brown, Bernardo SeguraAbstract:1. Harmonia axyridis has invaded many regions of the world, with negative effects on local biodiversity, and thus it is of global concern for biological conservation. Recently it has invaded central Chile, one of the world's biodiversity hotspots, where the abundance and richness of ladybird species, particularly native species in agroecosystems, have declined following its arrival. 2. Harmonia axyridis is particularly abundant in spring in the valleys of central Chile, but there is a dramatic decline in its abundance during the hot summer months. 3. This study reports the occurrence of this invasive alien species in the summer at high altitudes (3578 m a.s.l.) in the Andes, which is the highest record worldwide. Individuals were observed on native cushion plants, in a unique environment rich in endemic species. Harmonia axyridis were active, reproducing and co-occurring with three other species of coccinellids. 4. The dispersal of H. axyridis and other coccinellids from the valleys to high altitudes could represent a mechanism to escape the adverse high temperatures during the summer, returning to the valleys in autumn. Our study highlights the need to study the impacts of invasive alien species across a range of habitats, including not only agricultural landscapes, but also extreme ecosystems.
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Harmonia axyridis (Coleoptera: Coccinellidae) in Asia: a re-examination of the native range and invasion to southeastern Kazakhstan and Kyrgyzstan
Biological Invasions, 2015Co-Authors: Marina J. Orlova-bienkowskaja, Andrey S. Ukrainsky, Peter M. J. BrownAbstract:Harmonia axyridis (Pallas) is an invasive ladybird spreading in several continents. It is native to East Asia, but its range in Asia has until now been poorly understood. The most complete map of the range of Harmonia axyridis in Asia has been compiled (432 localities). Harmonia axyridis occurs in the south-east of West Siberia, the south of East Siberia, the south of Russian Far East, the east of Kazakhstan, the north of Kyrgyzstan, Mongolia, China, North Korea, South Korea, Japan, and the north of Vietnam. Southeastern Kazakhstan and the north of Kyrgyzstan are not a part of the native range: the large Balkhash Desert is situated between this mountainous region and the nearest part of the native range (Altai mountains). The analysis of dates and places of findings indicates that Harmonia axyridis appeared in southeastern Kazakhstan and Kyrgyzstan after the construction of the Turkestan-Siberian Railway. It is hypothesized that the beetles crossed the desert along this railway.
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Ten years of invasion: Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Britain.
Ecological Entomology, 2015Co-Authors: Helen E. Roy, Peter M. J. BrownAbstract:1. Harmonia axyridis was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003. 2. The UK Ladybird Survey, a citizen science initiative involving online recording, was launched in 2005 to encourage people across Britain to track the spread of H. axyridis. Tens of thousands of people have provided records of H. axyridis and other species of ladybirds, creating an invaluable dataset for large-scale and long-term research. Declines in the distribution of seven (of eight assessed) native species of ladybird have been demonstrated, and correlated with the arrival of H. axyridis, using the records collated through the UK Ladybird Survey. 3. Experimental research and field surveys have also contributed to our understanding of the ecology of H. axyridis and particularly the process of invasion. Harmonia axyridis arrived in Britain through dispersal and introduction events from regions in which it was deliberately released as a biological control agent. The rapid spread of this species has been attributed to its high natural dispersal capability by means of both flight and anthropogenic transport. A number of factors have contributed to the successful establishment and indeed dominance of this polymorphic species within aphidophagous guilds, including high reproductive capacity, intra-guild predation, eurytopic nature, high resistance to natural enemies within the invaded range, and potentially phenotypic plasticity. 4. The global invasion by H. axyridis and subsequent research on this species has contributed to the general understanding of biological invasions.
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Decline in native ladybirds in response to the arrival of Harmonia axyridis: early evidence from England
Ecological Entomology, 2011Co-Authors: Peter M. J. Brown, Robert Frost, Julian Doberski, Tim H. Sparks, Richard Harrington, Helen E. RoyAbstract:1. Harmonia axyridis (Coleoptera: Coccinellidae) is an invasive non-native ladybird in Europe, where it was introduced as a biological control agent of aphids and coccids. 2. This study assesses changes to ladybird species assemblages, in arboreal habitats, over a 3-year period encompassing the invasion phase of H. axyridis in eastern England. The effects of H. axyridis and other factors (weather and prey availability) on native ladybirds are assessed. 3. Harmonia axyridis increased from 0.1% to 40% of total ladybirds sampled, whilst native aphidophagous species declined from 84% to 41% of total ladybirds. The actual number of native aphidophagous ladybirds per survey decreased from a mean of 19.7 in year 1, to 10.2 in year 3. 4. Three ladybird species in particular experienced declines: Adalia bipunctata, Coccinella septempunctata, and Propylea quattuordecimpunctata. Harmonia axyridis was the most abundant species by the end of the study. 5. The decline in native aphidophagous ladybirds could be attributed to competition for prey and intraguild predation of eggs, larvae, and pupae by H. axyridis. Physiological and behavioural traits of H. axyridis are likely to confer an advantage over native ladybird species.
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Encounters with an alien: Harmonia axyridis in Europe
2009Co-Authors: Helen E. Roy, Peter M. J. BrownAbstract:Invasive species are considered among the greatest threats to global biodiversity. The rapid increase in introduced exotic species worldwide and the potential of these species to become invasive has ecological and evolutionary consequences. Ladybirds have a long history of use as biological control agents against pest insects. Indeed, the Australian vedalia ladybird, Rodolia cardinalis, is heralded as marking the advent of modern biological control. Harmonia axyridis was released in many European countries through the 1980 and 1990s and just a decade later there were many reports of establishment. Harmonia axyridis is now widely regarded as an Invasive Alien Species (IAS) first and foremost because it threatens the diversity of native aphidophagous species and may contribute to biotic homogenization. There are many lessons to be learnt from H. axyridis as a model IAS to help prevent, or mitigate, subsequent releases of high risk organisms. I will review the status of H. axyridis in Europe, from introduction to establishment, and consider where our encounters with this alien are contributing to understanding of biological invasions.
L Williams - One of the best experts on this subject based on the ideXlab platform.
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The Exotic Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) and Other Coccinellids in Selected Vineyards of the Western Cape Province, South Africa
African Entomology, 2017Co-Authors: K. A. Achiano, Jan H Giliomee, E. Allsopp, L WilliamsAbstract:Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is an exotic ladybird, first recorded in South Africa in 2004, where it was introduced factitiously. In this study the seasonal occurrence of H. axiridis and other coccinellids were monitored in four vineyards and the adjacent windbreaks over three growing seasons in the Western Cape Province, South Africa. Harmonia axyridis made up the highest mean number of coccinellids collected per site over the collecting period, followed by Hippodamia variegata, Cheilomenes lunata, Exochomus flavipes and Micraspis sp. No indigenous parasitoids were observed attacking H. axyridis. The numbers of H. axyridis on the vines were negatively correlated with temperature but positively with rainfall. In view of the migration of H. axyridis from the vines in December, they appear not to pose any risk of contaminating grapes during harvest and tainting wine as most wine grapes are harvested from January onwards.
Helen E. Roy - One of the best experts on this subject based on the ideXlab platform.
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Life cycle of Harmonia axyridis in central Europe
BioControl, 2017Co-Authors: Alois Honek, Helen E. Roy, Zdenka Martinkova, A. F. G. Dixon, Jiří Skuhrovec, Marek Brabec, Stanislav PekárAbstract:The development and reproduction, and maximum number of generations across seasons were ascertained for populations of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Central Europe. Number of generations was calculated using the thermal characteristics of development and summation of daily average air temperatures, in 2007–2016. This species can produce 2–3 generations per year. However, there is insufficient time for it to achieve its full reproductive potential. Delayed emigration from hibernacula (late April) shortened the period of seasonal activity by 1–6%. Breeding occurred from May to mid September. Oviposition continued into late summer, which left insufficient time for the late-hatching immatures to complete their development before the onset of winter. A high mobility, opportunistic use of prey patches and weak tendency to enter dormancy provide the potential for population increase by extending the period of development of immatures at the risk of failure if the cold period comes early.
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In the shadow of the condor: invasive Harmonia axyridis found at very high altitude in the Chilean Andes
Insect Conservation and Diversity, 2017Co-Authors: Audrey A. Grez, Helen E. Roy, Tania Zaviezo, Peter M. J. Brown, Bernardo SeguraAbstract:1. Harmonia axyridis has invaded many regions of the world, with negative effects on local biodiversity, and thus it is of global concern for biological conservation. Recently it has invaded central Chile, one of the world's biodiversity hotspots, where the abundance and richness of ladybird species, particularly native species in agroecosystems, have declined following its arrival. 2. Harmonia axyridis is particularly abundant in spring in the valleys of central Chile, but there is a dramatic decline in its abundance during the hot summer months. 3. This study reports the occurrence of this invasive alien species in the summer at high altitudes (3578 m a.s.l.) in the Andes, which is the highest record worldwide. Individuals were observed on native cushion plants, in a unique environment rich in endemic species. Harmonia axyridis were active, reproducing and co-occurring with three other species of coccinellids. 4. The dispersal of H. axyridis and other coccinellids from the valleys to high altitudes could represent a mechanism to escape the adverse high temperatures during the summer, returning to the valleys in autumn. Our study highlights the need to study the impacts of invasive alien species across a range of habitats, including not only agricultural landscapes, but also extreme ecosystems.
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Ten years of invasion: Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Britain.
Ecological Entomology, 2015Co-Authors: Helen E. Roy, Peter M. J. BrownAbstract:1. Harmonia axyridis was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003. 2. The UK Ladybird Survey, a citizen science initiative involving online recording, was launched in 2005 to encourage people across Britain to track the spread of H. axyridis. Tens of thousands of people have provided records of H. axyridis and other species of ladybirds, creating an invaluable dataset for large-scale and long-term research. Declines in the distribution of seven (of eight assessed) native species of ladybird have been demonstrated, and correlated with the arrival of H. axyridis, using the records collated through the UK Ladybird Survey. 3. Experimental research and field surveys have also contributed to our understanding of the ecology of H. axyridis and particularly the process of invasion. Harmonia axyridis arrived in Britain through dispersal and introduction events from regions in which it was deliberately released as a biological control agent. The rapid spread of this species has been attributed to its high natural dispersal capability by means of both flight and anthropogenic transport. A number of factors have contributed to the successful establishment and indeed dominance of this polymorphic species within aphidophagous guilds, including high reproductive capacity, intra-guild predation, eurytopic nature, high resistance to natural enemies within the invaded range, and potentially phenotypic plasticity. 4. The global invasion by H. axyridis and subsequent research on this species has contributed to the general understanding of biological invasions.
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Escape from parasitism by the invasive alien ladybird, Harmonia axyridis
Insect Conservation and Diversity, 2013Co-Authors: Richard Comont, Richard Harrington, Bethan V. Purse, William M. Phillips, William E. Kunin, Matthew Hanson, Owen T. Lewis, Chris R. Shortall, Gabriele Rondoni, Helen E. RoyAbstract:1. Alien species are often reported to perform better than functionally similar species native to the invaded range, resulting in high population densities, and a tendency to become invasive. The enemy release hypothesis (ERH) explains the success of invasive alien species (IAS) as a consequence of reduced mortality from natural enemies (predators, parasites and pathogens) compared with native species. The harlequin ladybird, Harmonia axyridis, a species alien to Britain, provides a model system for testing the ERH. 2. Pupae of H. axyridis and the native ladybird Coccinella septempunctata were monitored for parasitism between 2008 and 2011, from populations across southern England in areas first invaded by H. axyridis between 2004 and 2009. In addition, a semi-field experiment was established to investigate the incidence of parasitism of adult H. axyridis and C. septempunctata by Dinocampus coccinellae. 3. Harmonia axyridis pupae were parasitised at a much lower rate than conspecifics in the native range, and both pupae and adults were parasitised at a considerably lower rate than C. septempunctata populations from the same place and time (H. axyridis: 1.67%; C. septempunctata: 18.02%) or in previous studies on Asian H. axyridis (2–7%). We found no evidence that the presence of H. axyridis affected the parasitism rate of C. septempunctata by D. coccinellae. 4. Our results are consistent with the general prediction that the prevalence of natural enemies is lower for introduced species than for native species at early stages of invasion. This may partly explain why H. axyridis is such a successful IAS.
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Coat of many colours: colour pattern polymorphism and invasion by the harlequin ladybird Harmonia axyridis
2012Co-Authors: Helen E. Roy, Richard Comont, Clare Kessel, Beth PurseAbstract:The invasive alien harlequin ladybird, Harmonia axyridis, is a polymorphic species. Melanic and non-melanic individuals can be found in Britain. The UK Ladybird Survey receives occurrence records of H. axyridis including information on colour pattern form. Here we examine the frequency of colour pattern forms, spatially and temporally, and the influence of the different forms on the invasion process.
Francois Roets - One of the best experts on this subject based on the ideXlab platform.
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Habitat Preferences of the Invasive Harlequin Ladybeetle Harmonia axyridis (Coleoptera: Coccinellidae) in the Western Cape Province, South Africa
African Entomology, 2017Co-Authors: V.o. Mukwevho, James S. Pryke, Francois RoetsAbstract:The invasive and predatory harlequin lady beetle, Harmonia axyridis, has been introduced as a biological control agent to many agricultural areas worldwide and has now spread from agricultural to natural habitats where it threatens native arthropod biodiversity. The aim of this study was to determine how H. axyridis uses the local landscape during different times of the year in the Western Cape Province, South Africa. We also determined its association to native arthropod diversity. Harmonia axyridis adults and larvae, as well as arthropod herbivores, predators and other ladybeetles were sampled every second month for a year with a vacuum sampler in vineyards, natural habitats, edges between natural habitats and vineyards, and urban areas. Highest adult and larval H. axyridis abundance occurred in urban areas during all sampling periods, with a peak in May and July (winter). Vineyards and natural vegetation had very low abundances of H. axyridis. Harmonia axyridis had some, but limited effect on the local...
Qu Ai-jun - One of the best experts on this subject based on the ideXlab platform.
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The Influence of Neonicotinoid Insecticides on the Orientation of Harmonia axyridis to Plant and Prey Combinations
World Pesticides, 2012Co-Authors: Qu Ai-junAbstract:The orientation of Harmonia axyridis to the apple leaves and prey combinations was investigated with Y olfactometer.The results showed that un-injured apple leaves did not produce plant volatiles attractive to H.axyridis,but after injured by Aphis citricola or Myzus malisuetus,they produced plant volatiles attractive to H.axyridis.Compared to the control,the five neonicotinoid insecticides can not almost affect the foraging behavior of H.axyridis.
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Study on the selection effect of Harmonia axyridis ab.conspicua to Chaitophorus populeti and C.populialbae
Liaoning Forestry Science and Technology, 2011Co-Authors: Qu Ai-junAbstract:Harmonia axyridis ab.conspicua was one of important predators of Chaitophorus populeti and C.populialbae.Selection effect of Harmonia axyridis ab.conspicua to Chaitophorus populeti and C.populialbae was investigated in lab.The result showed that change of EG-S value and EI value was from 1 to 0,EI value was in order to decrease between 0 and-1 during synchronic augmentation of Chaitophorus populeti and C.populialbae population.This result indicated that Harmonia axyridis ab.conspicua was more likely to prey on C.populialbae.When the quantity of Chaitophorus populeti was unchanging,but the quantity of C.populialbae was increased,the result showed that EG-S value and EI value was from 1 to 0,EI value was in order to decrease between 0 and-1.It indicated that Harmonia axyridis ab.conspicua was more likely to prey on C.populialbae.When the quantity of C.populialbae was unchanging,but the quantity of Chaitophorus populeti was increased,the result showed that EG-S value and EI value was from +1 to ∞,EI value was in order to increase between 0 and +1.It indicated that Harmonia axyridis ab.conspicua was more likely to prey on Chaitophorus populeti.
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Study on selective preferences of Harmonia axyridis(Pallas) collected from different habitats to predating aphids
China Plant Protection, 2006Co-Authors: Qu Ai-junAbstract:The selective preferences of Harmonia axyridis(Pallas) collected from different habitats to predating aphids were measured with olfactometer.Results showed Harmonia axyrids(Pallas) has strong selective preference to predating aphids.The experiments revealed that this kind of ladybugs could migrate between different habitats.
