Under natural conditions, prey resources may fluctuate considerably in space and time; and predators are continuously faced with challenges of resource availability and use. In this study, effects of fluctuations (scarce/optimal/abundant) in biomass of pea aphid (Acyrthosiphon pisum (Harris); Hemiptera: Aphididae) during rearing and experimental conditions on certain predatory attributes (consumption rate/conversion, efficiency/growth rate) of two sympatric aphidophagous Coccinellidae (Coleoptera) were evaluated. Results revealed significant influence of rearing conditions on conversion efficiency and growth rate; and experimental conditions on all three predation attributes of Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae). Larvae/adults of M. sexmaculatus had similar consumption rates per rearing condition, but exhibited highest and lowest consumption rates when abruptly shifted to abundant and scarce prey experimental conditions. Further, scarce prey reared larvae/adults of M. sexmaculatus displayed highest conversion efficiency and growth rate on optimal/abundant prey experimental condition(s). However, all three predation attributes of larvae/adults of Propylea dissecta (Mulsant) (Coleoptera: Coccinellidae) were influenced substantially by both the rearing and experimental conditions; and scarce prey reared larvae/adults exhibited highest predation attributes on optimal/abundant prey experimental condition(s). Moreover, predation attributes of M. sexmaculatus were higher than P. dissecta on the three experimental conditions. Therefore, this study suggests that M. sexmaculatus has a better compensatory ability to overcome prey resource fluctuation than P. dissecta.

Blueberry fruit fly, Rhagoletis mendax Curran (Diptera: Tephritidae), females deposit a host-marking pheromone (HMP) on the surface of fruit immediately after oviposition that deters oviposition by female conspecifics. We collected this HMP from artificial oviposition devices and faeces. In subsequent two-choice bioassays, gravid females showed a strong preference for untreated oviposition devices as compared to those treated with extracts from either of these two sources. The methods described for collecting HMP of R. mendax will be useful for its eventual identification and synthesis, with potential applications in R. mendax management.

The balsam gall midge Paradiplosis tumifex Gagné (Diptera: Cecidomyiidae) is a major pest for the Christmas tree industry. This galler is frequently associated with the inquiline Dasineura balsamicola (Lintner) (Diptera: Cecidomyiidae), which is involved in the dynamics of the galler. Despite their importance, seasonal ecology of both midges under the climatic conditions prevailing in eastern Canada is still poorly understood. More importantly, nothing has yet been done to fully assess the impact of temperature on these insects, at key events such as adult emergence and larval overwintering. Here we followed P. tumifex and D. balsamicola spring phenology in the field, as well as their survival during winter diapause under simulated climatic scenarios in the laboratory. We observed spring asynchrony between fir host trees and P. tumifex in the first year of study, but under prevailing epidemic conditions, we observed no impact on summer abundance. We clarified available knowledge on their ecology, showing that overwintering habitats and strategies differ between the galler and its inquiline, which should alter pest control strategies. Experimental overwintering data suggest that diapausing conditions affect these species differentially and could potentially impact the spring sex ratio of their midges, which tends to be strongly female biased.

Cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), is a serious pest of several crops throughout the world, representing millions of United States of America dollars worth of damage. This pest can adapt to various cropping systems in a wide geographical range and has high migratory potential. It features high fecundity and can develop resistance to almost all insecticides used for its management. Several investigations to develop microsatellite markers for H. armigera have not been successful because of the paucity of microsatellites in the lepidopteran genome. As well, collections of H. armigera from cotton fields of southern and western India were not yet studied for molecular genetic diversity. The current study aimed to screen publicly available expressed sequence tag resources for simple sequence repeats and assess their potential as DNA markers for assessment of gene flow between collections of southern and western India. We identified 30 polymorphic microsatellites for potential use in diversity analysis of H. armigera collections. Genetic diversity analysis revealed that the collections were widely diverse with population differentiation index (Fst) of 0.17. Furthermore, gene flow analysis revealed a mean frequency of private alleles of 11% within the collections. The microsatellite resources we developed could be widely used for molecular diversity or population genetic research involving this important pest of cotton and food crops.

Field collected wireworms (Coleoptera: Elateridae) intended for laboratory studies often die during storage from Metarhizium Sorokin (Clavicipitaceae) infection and other causes. To determine optimal storage conditions for Agriotes obscurus (Linnaeus), freshly collected larvae were stored in regular and sterilised soil, with and without access to food (potato slices), at 12 °C and 16 °C, for six months to determine which conditions resulted in the lowest wireworm mortality. Survival was highest when wireworms were stored in sterilised soil, at 12 °C, in the absence of food. Food availability increased wireworm mortality from Metarhizium infection and other causes, but decreased the number of missing wireworms. Wireworm weight change during the study was highest in treatments where wireworms had access to food. The expected effect of food deprivation on wireworm energetic state and immune response are discussed in context with these findings.

Almost 100 years have passed since J.M. Swaine, the assistant entomologist in charge of Forest Insect Investigations, wrote, “Canadian bark-beetles: a preliminary classification, with an account of the habits and means of control”. The goal was to “put into the hands of practical foresters information of inestimable practical value… to prevent the continued loss of timber now being destroyed” by “the most insidious enemies of the forest”. In this paper, we celebrate Swaine’s pioneering work by summarising the foundational aspects of his early treatise of 1918: the “general habits” of bark beetles, classifications of their behaviour, causes of population increase, and mitigation tactics. In the founding text, Swaine identified all major Dendroctonus Erichson (Coleoptera: Curculionidae) bark beetles found in Canada, although details on life histories were scarce. We summarise current knowledge of the life histories and population dynamics of the spruce beetle, D. rufipennis Kirby; the Douglas-fir beetle, D. pseudotsugae Hopkins; the eastern larch beetle, D. simplex; and address the current range expansion of mountain pine beetle, D. ponderosae Hopkins. We review how aspects of global change, such as invasive species, have altered the population dynamics of certain bark beetles. Finally, we conclude with lessons from two of the many past contributors to bark beetle ecology in Canada, J.M. Swaine and H.A. Richmond.

To investigate natural enemies of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in northeastern China, we conducted field surveys of ash (Fraxinus Linnaeus (Oleaceae)) trees in semi-natural forests and plantations at variable EAB densities from 2008 to 2013. Our surveys revealed a complex of natural enemies including eight hymenopteran parasitoids and two apparently parasitic Coleoptera, woodpeckers, and several undetermined mortality factors. Parasitoid complex abundance and its contribution to EAB mortality varied with the time of year, type of ash stands, and geographic regions. The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) and the larval parasitoid Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) were frequently observed in Jilin, Liaoning, and Heilongjiang provinces and in Beijing, but not in Tianjin. Spathius agrili Yang (Hymenoptera: Braconidae), however, was more prevalent near Beijing and further south in Tianjin. Larvae of two species of apparently parasitic beetle, Tenerus Laporte (Coleoptera: Cleridae) species and Xenoglena quadrisignata Mannerheim (Coleoptera: Trogossitidae), were also recovered attacking overwintering EAB in Liaoning Province, with Tenerus species being a dominant mortality agent (~13%). Our findings support the need to consider the geographic origin of insect natural enemies for EAB biocontrol, as well as an expanded foreign exploration for EAB natural enemies throughout its native range in Asia.

A novel “rearing-tube” method was developed and used to investigate the performance of mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), with its three main ophiostomatalean fungal symbionts, Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer, and Wingfield (Ophiostomataceae), Ophiostoma montium (Rumbold) von Arx (Ophiostomataceae), and Leptographium longiclavatum Lee, Kim, and Breuil (Ophiostomataceae). Transparent glass tubes filled with sterile ground jack pine (Pinus banksiana Lambert; Pinaceae) phloem and sapwood (9:1 ratio) were used to rear MPB from egg to adult with each fungus under controlled environmental conditions. Mountain pine beetle mortality was higher and development longer in fungus-free controls compared to fungal treatments. Among fungal treatments, insects developed faster, constructed shorter larval galleries, and had fewer supernumerary instars with L. longiclavatum. Insect survival was not affected by fungal treatments. Hyphal extension through the rearing medium was fastest for L. longiclavatum. Phloem nitrogen was reduced significantly by the presence of L. longiclavatum. Results support the hypothesis that ophiostomatalean symbionts provide benefits to MPB. The rearing-tube method is useful to tease apart confounding interspecific interactions between bark beetles and symbiotic fungus species.

Whitebark pine, Pinus albicaulis Engelmann (Pinaceae), a foundational species of North American subalpine ecosystems, is endangered across its range and continued decline is inevitable. Little is known about the invertebrate fauna associated with this species which, if specific to whitebark pine, may also be threatened or endangered. We compared the composition of saproxylic beetle assemblages associated with whitebark pine and co-occurring lodgepole pine, Pinus contorta latifolia (Engelmann) Critchfield (Pinaceae), recently killed by mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), in subalpine forests in Alberta, Canada. Redundancy and rarefaction analyses revealed that beetle assemblage composition was influenced by snag class (i.e., time since death) but differed little among the two pine species within snag classes. However, a subset of the assemblage known to be associated with the MPB differed significantly in composition between the two pines. No common species were exclusively associated with whitebark pines; however, seven species were rarely collected only on whitebark pine. With the possible exception of these rare species, felling and burning infested whitebark pines to control the MPB will not likely endanger saproxylic beetles associated with this tree.

The alfalfa weevil (Hypera postica (Gyllenhal): Coleoptera: Curculionidae) is an invasive pest of alfalfa (Medicago sativa Linnaeus; Fabaceae) in the Holarctic region. Across the wide geographic distribution of the species different local adaptions have been observed. Further, several distinct mitochondrial lineages have been discovered, which have been treated as western and Egyptian/eastern strains. However, our knowledge of the biogeography of H. postica is largely limited to North American and Japanese populations. We sampled the species from four locations in Iran and two countries in Europe (Poland and Czech Republic) and sequenced the mitochondrial COI gene to detect patterns of mitochondrial DNA divergence among Iranian and European strains. We detected two groups separated by a deep molecular split, even justifying the distinction of two molecular operational taxonomic units. Joint analyses with previously published sequences suggest that the European samples may represent the western strain, whereas both the western and Egyptian/eastern strains can be found in Iran. This distribution of genetic lineages may be the result of human-mediated translocations. The directionality, however, cannot be inferred. Our data suggest that translocations may have led to the coexistence of multiple H. postica lineages in some parts of the world, e.g., Iran. We discuss these findings against the background of the current taxonomy of H. postica.

Phanerotoma libertinecidanew species (Hymenoptera: Braconidae: Cheloninae) is described and put in context with the latest North American revision of the genus. The species has been reared repeatedly from Grapholita libertina Heinrich (Lepidoptera: Tortricidae), which is found on lingonberry (Vaccinium vitis-idaea var. minor Loddiges, Loddiges, and Loddiges (Ericaceae)). Its natural history is also described.

A number of insect species in a variety of families and orders damage early regenerating forests. Successful management of pests of regenerating forests requires detailed information on the natural history of the damaging organism, including the factors that increase risk, and a careful assessment of the risk mitigation options. Decision support systems, in the form of stand models capable of incorporating pest management options are required to guide decisions in terms of the expected yields under various pest management scenarios. In this paper we review research to date on the natural history and damage of the most important insect pests of regenerating forests in Canada and propose a framework for risk assessment. Canadian scientists have been active contributors to the research that advanced this field, from the early descriptive studies, to the development of practical tools to assist industry in managing pests of young forests.

Discovery of the non-native Anoplophora glabripennis Motschulsky (Coleoptera: Cerambycidae) in Ontario, Canada, in 2003 led to the implementation of an eradication programme. The plan consisted of removing all infested trees and all trees belonging to a genus considered suitable for complete development of this wood-borer that were found within 400 m of an infested tree; however, many of the trees within that 400 m belonged to genera for which suitability for development of A. glabripennis was questionable or unknown. We visually inspected over 3000 such trees annually for the three years following removal of infested trees. All but one tree were unattacked: an ash (Fraxinus excelsior Linnaeus (Oleaceae)) tree had signs of oviposition and early-instar development, but not of adult emergence. Before that survey, we had found only one other species with questionable suitability, a little leaf linden (Tilia cordata Miller (Malvaceae)) that had many signs of oviposition, but no evidence of full development, suggesting resistance to A. glabripennis. Both of these trees were within 200 m of the most heavily infested maple (Acer platanoides Linnaeus (Sapindaceae)) tree found in that infestation, suggesting that colonisation of trees with questionable or unknown suitability might occur mostly where population pressure is high.

The balsam twig aphid, Mindarus abietinus Koch (Hemiptera: Aphididae), is one of the most important pests of balsam fir (Abies balsamea (Linnaeus) Miller; Pinaceae) grown as Christmas trees in eastern North America. Aphid feeding on the current-year shoots results in needle distortion and shoots stunting, which reduces the aesthetic value of balsam fir trees and can have substantial economic impact. Syrphidae (Diptera) fly predators attacking this aphid are poorly known. We identified four species attacking the balsam twig aphid. Syrphus torvus Osten Sacken (Diptera: Syrphidae) was the most abundant species followed by Eupeodes lapponicus (Zetterstedt) (Diptera: Syrphidae) and Eupeodes americanus (Wiedemann) (Diptera: Syrphidae). We described the seasonal natural history of the two most abundant syrphids feeding on this aphid and we studied their synchrony with their prey. Syrphid larval density on balsam fir shoots increased rapidly and closely followed density of the balsam twig aphid. We also reported heavy parasitism of syrphid pupae by two Hymenoptera on tree foliage but lower parasitism on pupae in the soil under trees. Several cases of multiple parasitism and hyperparasitism were observed in syrphid pupae under trees. Abundance of predaceous syrphid species was higher in untreated balsam fir plantations compared with treated plantations. More research is needed to understand the role and the impact of these predators on balsam twig aphid population dynamics.

The walnut twig beetle (WTB), Pityophthorus juglandis Blackman (Coleoptera: Curculionidae), vectors a fungus, Geosmithia morbida Kolařík, Freeland, Utley, and Tisserat (Ascomycota: Hypocreales), which colonises and kills the phloem of walnut and butternut trees, Juglans Linnaeus (Juglandaceae). Over the past two decades, this condition, known as thousand cankers disease (TCD), has led to the widespread mortality of Juglans species in the United States of America. Recently the beetle and pathogen were discovered on several Juglans species in northern Italy. Little is known about the extra-generic extent of host acceptability and suitability for the WTB. We report the occurrence of both the WTB and G. morbida in three species of wingnut, Pterocarya fraxinifolia Spach, Pterocarya rhoifolia Siebold and Zuccarini, and Pterocarya stenoptera de Candolle (Juglandaceae) growing in the United States Department of Agriculture-Agricultural Research Service, National Clonal Germplasm Repository collection in northern California (NCGR) and in the Los Angeles County Arboretum and Botanic Garden in southern California, United States of America. In two instances (once in P. stenoptera and once in P. fraxinifolia) teneral (i.e., brood) adult WTB emerged and were collected more than four months after infested branch sections had been collected in the field. Koch’s postulates were satisfied with an isolate of G. morbida from P. stenoptera, confirming this fungus as the causal agent of TCD in this host. A survey of the 37 Pterocarya Kunth accessions at the NCGR revealed that 46% of the trees had WTB attacks and/or symptoms of G. morbida infection. The occurrence of other subcortical Coleoptera associated with Pterocarya and the first occurrence of the polyphagous shot hole borer, a species near Euwallacea fornicatus Eichhoff (Coleoptera: Curculionidae), in Juglans are also documented.

We evaluated the efficacy of fipronil baits in suppressing or eliminating field colonies of Microtermes mycophagus (Desneux) (Blattodea: Termitidae) an important subterranean termite pest in Pakistan. We tested two doses (10 and 30 ppm) of fipronil in toilet paper baits, chosen from laboratory repellency tests. We monitored four colonies for foraging activity for one month before baiting, and mapped foraging territories with termites marked with Nile Blue A and agonistic tests. Before the fipronil baits were installed there were averages of 782–1938 workers and soldiers per bait station in the four colonies. After baiting, the colonies were eliminated as there were no workers per bait station, whereas the control colony had an average of 1142 workers per bait station. The three possibly eliminated colonies consumed around 47 mg of fipronil formulation (4.7 mg active ingredient) in 45–90 days. Our results suggest that baits containing fipronil could provide an economical and feasible alternative for the management of M. mycophagus in structures and buildings in Pakistan.

Mechanistic species niche models were used to map the seasonal spatio-temporal dynamics of biological control pressure. Future climate scenarios were applied to these models to identify potential future trends in the patterns of biological control pressure through space and time during an annual seasonal cycle. Peristenus digoneutis Loan (Hymenoptera: Braconidae) is a parasitoid of Lygus Hahn (Hemiptera: Miridae) species, important pests of glasshouse and field crops throughout Europe and North America. Consistent with theoretical expectations, the modelled potential range of P. digoneutis expanded polewards and contracted from its southern temperature range limits. However, its distribution did not change consistently across continents or countries. Locations near the outer limits of the current modelled distribution were more sensitive to changes in future climates than locations near the central core. Weekly climate suitability and stress maps were developed to provide insight into seasonal adjustments that accompany changes in the potential range of pest species and their natural enemies. Climate change may increase the number of Lygus generations in western Canada allowing P. digoneutis to establish in areas, where biological control attempts had failed in the past.

We describe three new genera and four new species (three named) of siricomorph sawflies (Hymenoptera: Symphyta) from the Ypresian (early Eocene) Okanagan Highlands: Pamphiliidae, Ulteramus republicensisnew genus, new species from Republic, Washington, United States of America; Siricidae, Ypresiosirex orthosemosnew genus, new species from McAbee, British Columbia, Canada; and Cephidae, Cuspilongus cachecreekensisnew genus, new species from McAbee and another cephid treated as Cephinae species A from Horsefly River, British Columbia, Canada. These are the only currently established occurrences of any siricomorph family in the Ypresian. We treat the undescribed new siricoid from the Cretaceous Crato Formation of Brazil as belonging to the Pseudosiricidae, not Siricidae, and agree with various authors that the Ypresian Megapterites mirabilis Cockerell is an ant (Hymenoptera: Formicidae). The Miocene species Cephites oeningensis Heer and C. fragilis Heer, assigned to the Cephidae over a century and a half ago, are also ants. Many of the host plants that siricomporphs feed upon today first appeared in the Eocene, a number of these in the Okanagan Highlands in particular. The Okanagan Highlands sites where these wasps were found also had upper microthermal mean annual temperatures as are overwhelmingly preferred by most modern siricomorphs, but were uncommon in the globally warm Ypresian, only found then in higher elevations and highest latitudes.

Palmistichus elaeisis Delvare and LaSalle, Tetrastichus howardi (Olliff), and Trichospilus diatraeae Cherian and Margabandhu (Hymenoptera: Eulophidae) are promising candidates for the control of sugarcane borer, Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae). The fungi Beauveria bassiana (Balsamo) Vuillemin (Cordycipitaceae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Clavicipitaceae) also can be used to control sugarcane borers plus leafhoppers (Hemiptera: Cercopidae) in sugarcane. This observation motivated us to investigate whether entomopathogenic fungi can affect biological aspects of these parasitoids. Diatraea saccharalis pupae (24 hours in age) were exposed to parasitism by three females of each eulophid species for 72 hours and then placed in small tubes. A contact surface treated with 1 mL of fungal suspension was placed inside each tube with the parasitised pupae at concentrations of 1×109, 5×109, or 10×109 conidia mL−1 of M. anisopliae and B. bassiana. Exposure to fungi reduced emergence of adult P. elaeisis, but not of T. howardi and T. diatraeae. Life cycle duration, progeny, and sex ratio of P. elaeisis were not affected by exposure. Exposure was associated with decreased longevity for both sexes of T. howardi and in males of P. elaeisis, but not at levels expected to affect their performance as biocontrol agents. In general, the exposure of eulophid species developing in pupae of D. saccharalis exposed to entomopathogenic fungi, did not compromise the biological aspects of these parasitoids.

The tomato looper, Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae), is a major pest that feeds on some fodder crops, vegetables, and ornamental plants in diverse plant families. We studied the effect of different cultivars of tomato including: Cal.JN3, Hed Rio Grande, Rio Grande UG, SUN 6108 f1, Super crystal, and Super strain B on the life history of C. chalcites under laboratory conditions (25±1 °C, 65±5% relative humidity, and 16:8 (light:dark hours). Data were analysed using the age-stage, two-sex life table method. Tomato cultivars had significant effects on developmental time of larvae, pupae, and total preadult stages of C. chalcites. The longest (17.39 days) and the shortest (13.93 days) larval period were observed on Hed Rio Grande and SUN 6108 f1, respectively. The longest pupal period was observed on Cal.JN3 (12.16 days) and Hed Rio Grande (12.11 days) compared with other cultivars. The lowest amount of larval growth index and rate of ovipositon days was observed on Cal.JN3. The results of this study revealed that Cal.JN3 and Hed Rio Grande were the less suitable cultivars to C. chalcites compared with other cultivars studied and can be used in integrated pest management programme of this pest.