@article {11916,
	title = {Host activity and wasp experience affect parasitoid wasp foraging behaviour and oviposition on nematode-infected larvae of the forestry pest Hylobius abietis},
	journal = {Ecological Entomology},
	volume = {37},
	number = {4},
	year = {2012},
	month = {Aug},
	pages = {269-282},
	abstract = {1. Entomopathogenic nematodes (EPN) are currently being used as introduced biological control agents against the larvae of the native European forestry pest Hylobius abietis L. which develop under the bark of stumps and roots of newly dead conifer trees. 2. The potential for resource competition between gregarious ectoparasitoid Bracon hylobii Ratz and EPN by recording oviposition and related behaviours of B. hylobii females on EPN-infected H. abietis larvae was investigated. Wasps did not parasitise EPN-infected host larvae that were dead when presented, but naive and experienced wasps parasitised live EPN-infected hosts. Naive wasps parasitised live EPN-infected hosts significantly less frequently than healthy hosts only when the infected larvae were close to death (i.e. died during 24-h trial). Parasitism by experienced wasps was unaffected by host infection. 3. Wasp probing and oviposition were positively associated with the amount of host movement. Preventing H. abietis larvae from chewing on bark significantly reduced parasitism by naive, but not experienced wasps. 4. The number of eggs per clutch was not affected by bark chewing or EPN-infection of H. abietis larvae. 5. Naive and experienced B. hylobii parasitised two abnormal hosts (larvae of coleopteran Rhagium bifasciatum Fabricius and lepidopteran Galleria mellonella L.), both of which moved and chewed on bark during trials. 6. It was concluded that B. hylobii can use vibrational cues generated by host movement and feeding to locate hosts at short range and accepts unsuitable (EPN-infected or abnormal) hosts as long as these create such cues. The implications for competition between B. hylobii and EPN and possible ways of minimising it when applying EPN are discussed.},
	keywords = {Hylobius abietis},
	isbn = {0307-6946},
	author = {Harvey, Christopher D. and Griffin, Christine T.}
}
@article {11915,
	title = {The impact of entomopathogenic nematodes on a non-target, service-providing longhorn beetle is limited by targeted application when controlling forestry pest Hylobius abietis},
	journal = {Biological Control},
	volume = {62},
	number = {3},
	year = {2012},
	month = {Sep},
	pages = {NIL_0059-NIL_0068},
	abstract = {Entomopathogenic nematodes are being applied to tree stumps on coniferous clearfell sites in Europe for inundative biological control of the large pine weevil (Hylobius abietis; Coleoptera: Curculionidae), a major forestry pest. We investigated the risk that two nematode species, Steinernema carpocapsae and Heterorhabditis downesi (Nematoda: Rhabditidae), present to longhorn beetle Rhagium bifasciatum (Coleoptera: Cerambycidae), a service-providing, non-target saproxylic insect on clearfell sites. In a Petri dish assay, larvae of R. bifasciatum were less susceptible (LC50 24-42) than pupae or adults (LC50 <= 10) to infective juveniles (IJs) of S. carpocapsae and H. downesi. S. carpocapsae and H. downesi reproduced within R. bifasciatum larvae, pupae and adults, with up to 130,000 IJs emerging per insect. When we applied 1.8 million IJs (half the number recommended per tree stump containing pine weevil) to deadwood logs in laboratory and field experiments, both nematode species infected more than 50\% of R. bifasciatum within the logs. Field application at a lower, more realistic rate (18,000 IJs per log) resulted in 0-11\% infection. The two nematode species caused similar rates of infection within logs and infected R. bifasciatum larvae more than 4 cm deep within the wood. On six clearfell sites sampled one to twelve months after S. carpocapsae had been inundatively applied to tree stumps for suppression of pine weevil, < 10\% of deadwood logs contained infected R. bifasciatum and < 4\% of 1989 R. bifasciatum individuals in logs were infected. Infection was recorded a year after nematodes had been applied, however, suggesting that nematodes were recycling within logs in the field. Incidence of R. bifasciatum infection decreased significantly with increasing distance between a log and the nearest treated tree stump. Thus, our results indicate that entomopathogenic nematodes can infect and recycle in R. bifasciatum, but that the risk to this and other saproxylic non-target insects is limited by the targeted application of nematodes to tree stumps. (C) 2012 Elsevier Inc. All rights reserved.},
	keywords = {Hylobius abietis},
	isbn = {1049-9644},
	author = {Harvey, Christopher D. and Alameen, Khalil M. and Griffin, Christine T.}
}
@article {10852,
	title = {Pine weevils modulate defensive behaviour in response to parasites of differing virulence},
	journal = {Animal Behaviour},
	volume = {80},
	number = {2},
	year = {2010},
	month = {Aug},
	pages = {283-288},
	abstract = {Grooming and avoidance of contaminated areas are among the behavioural defences employed by animals against parasites. Antiparasite defence behaviour is costly in terms of time, energy and/or food foregone and therefore animals are expected to modulate their defences depending on the risk of attack and/or the severity of the symptoms caused. We tested the hypothesis that an insect host invests more in defence against more virulent (more likely to cause death) than less virulent parasites. We tested avoidance and grooming of adult pine weevils, Hylobius abietis, in response to infective juveniles of two species of entomopathogenic nematodes, the more virulent Steinernema carpocapsae and less virulent Heterorhabditis downesi. Weevils avoided feeding on a substrate contaminated with S. carpocapsae but not H. downesi. Weevils also groomed more when their bodies were contaminated with S. carpocapsae than either H. downesi or water. We also made direct observations of nematodes on weevils. When equal numbers of nematodes were applied to weevils more S. carpocapsae than H. downesi moved actively on the weevil{\textquoteright}s cuticle. Thus, the differential response of weevils to the two nematode species can be explained by the weevils detecting the more aggressive behaviour of S. carpocapsae than H. downesi, which corresponds to a higher probability of death. [copyright] 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.},
	keywords = {Hylobius abietis},
	isbn = {0003-3472; 1095-8282},
	author = {Ennis, Darragh E. and Dillon, Aoife B. and Griffin, Christine T.}
}
@article {10702,
	title = {Evict of infect? Managing populations of the large pine weevil, Hylobius abietis, using a bottom-up and top-down approach},
	journal = {Forest Ecology and Management},
	volume = {255},
	number = {7},
	year = {2008},
	month = {April 20},
	pages = {2634-2642},
	type = {Article},
	abstract = {Hylobius abietis is the most important pest of replanted coniferous sites in Northern Europe, where feeding by adult weevils can result in up to 100\% mortality of seedlings. Field trials were conducted with the aim of reducing H. abietis populations developing in Sitka spruce stumps by increasing pressure from natural enemies (top-down pressure), and reducing the quality of stumps for development (bottom-up pressure). Top-down pressure was applied through inundative treatment of stumps with entomopathogenic nematodes (Heterorhabditis downesi or Steinernema carpocapsae). Bottom-up pressure was applied by treating stumps with the wood colonising fungus Trichoderma koningii. Natural levels of parasitism of H. abietis by the parasitoid Bracon hylobii and the effect of applied agents on B. hylobii were also investigated. Heterorhabditis downesi parasitised more immature weevils than S. carpocapsae, and significantly reduced numbers of adults emerging from stumps compared to controls. Entomopathogenic nematodes did not significantly impact on populations of B. hylobii, and over three sites the effects of both agents were additive. Stumps modified by application of the fungus (bottom-up pressure) did not have fewer H. abietis developing in, or emerging from them; however, development of H. abietis was more advanced in these stumps, and the success of natural enemies was differentially affected. T. koningii facilitated B. hylobii while having the opposite effect on entomopathogenic nematodes, suggesting that it affected the outcome of competition between the nematodes and the parasitoid.},
	keywords = {Hylobius abietis},
	isbn = {0378-1127},
	author = {Dillon, Aoife B. and Moore, Colm P. and Downes, Martin J. and Griffin, Christine T.}
}
