A widespread epizootic of the fungous disease caused by Entomophthora grylli Fres. occurred among grasshoppers in Saskatchewan in 1963. Camnula pellucida (Scudder), in particular, suffered high mortality and was nearly wiped out in those areas of central and east-central Saskatchewan where heavy infestations had been present. Weather was warm and humid during the outbreak with above normal rainfall in the seriously affected areas.

Field-cage studies showed that proper timing of rainfall was essential for continuation and spread of the disease. Rainfall shortly after death of the diseased grasshopper induced profuse growth of conidiophores along with intense discharge of conidia. When death occurred during hot, dry weather, no sporulation was noted and the insects rapidly dried up. The interval from infection to death of the grasshopper was about 13 days.

The fungous disease also developed in natural field populations of Melanoplus bivittatus Say, but none was noted in field cages where this grasshopper was being reared alongside of or together with C. pellucida that were dying continuously from the disease; this suggests that different strains of E. grylli were involved.

The comparative ecology of conifer-feeding budworms in the genus Choristoneura Lederer (Lepidoptera: Tortricidae) in Canada is reviewed with emphasis on publications since 1980. Systematics and life history are updated and historical outbreak patterns and their current interpretation summarised. Recent evidence is analysed in the context of ecological interactions among three trophic levels; host plant, budworm herbivore, and natural enemies. The influence of weather and climate are viewed as modulating factors. The population behaviour of budworms is interpreted as the result of tri-trophic interactions that vary at different scales. The result of these multi-scale interactions is that despite shared phylogenetic constraints and common adaptations, different budworm species display different population behaviour because of specific ecological relationships with their respective hosts and natural enemies.

Solitary cavity-nesting bees, especially trap-nesting Megachilidae, have great potential as commercial pollinators. A few species have been developed for crop pollination, but the diversity, abundance, and potential pollination contributions of native cavity-nesting bees within agricultural systems have seldom been assessed. Our objectives were to compare the diversity and fecundity of cavity-nesting bees in Nova Scotia in natural ecosystems with those in apple orchards under three levels of management, using trap nests, and to determine whether any native bees show promise for development as pollinators. Our results show that species richness and numbers of bees reared from trap nests in commercially managed orchards, abandoned orchards, and natural habitats were similar, and species’ compositional patterns were not unique to specific habitats. Trap nests can be used to increase and maintain cavity-nesting bee populations within Nova Scotia apple orchards. Osmia tersula Cockerell (Megachilidae), which accounted for almost 45% of all bees captured and was the most abundant species nesting in all habitats evaluated, should be assessed for potential as a commercial pollinator of spring-flowering crops. The influence of natural cavities on bee species richness in trap-nesting surveys is also discussed.

Dendroctonus brevicomis Lec. responded in flight to combinations of insect- and host-produced volatiles. Emergent female beetles crushed at −70 °C, as well as synthetic exo-7-ethyl-5-methyl-6, 8-dioxabicyclo [3.2.1] octane (“brevicomin”) attracted both sexes of the western pine beetle when offered with oleoresin freshly tapped from the host, Pinus ponderosa Laws. Offered separately, these materials were inactive. Crushed emergent Dendroctonus ponderosae Hopk. males per se, however, attracted flying D. brevicomis in appreciable numbers. Dominance of either host odor or insect pheromone appeared to govern the sex ratio of the responding insects.

Larvae of Hyphantria cunea Drury were reared on early, mid-season, and late foliage collected from the same apple trees. Survival was significantly lower on late foliage and the fecundity of the moths decreased from 604 in the early series to 128 in the late. Half the filial generation was reared under nutritional stress on a deficient synthetic diet and the other half on a very favorable host, speckled alder. Under both conditions there was a strong transmitted influence of parental food quality on the viability of the eggs and on the ability of first-instar larvae to become established on food. The progeny of the late series did not survive beyond this instar. When the filial generation was subjected to nutritional stress, the influence of parental food was apparent throughout the larval, pupal and adult stages, with progeny of the early series having higher survival than those of the mid-season series. However, when the filial generation hail very favorable food, there was no significant difference in survival rates subsequent to the larval establishment period.

The quality of foliage available to univoltine populations of H. cunea depends largely on temperature. Thus, in the development of population models for this species, temperature should be treated as a variable having not only direct effects on establishment and survival each season, but also indirect effects on the quality of the progeny in the following season.

The adult Arthropoda occurring in, on, or emerging from 2,660 sporophores of the bracket fungus Polyporus betulinus (Bull.) Fr., growing on dead birch, are listed. Collections were made in New Brunswick, Quebec, Ontario, and Manitoba. Two hundred and fifty-seven species of Arthropoda, mainly insects and mites, were recorded; over 49,000 specimens were examined. Old, twice-wintered sporophores produce more species and more individuals. In general, the fungus is rich in species but rarely produces sizable populations of any one species.

When male Anagasta kühniella (Zell.) were released in a wind tunnel downwind of a scenting female they flew upwind, but on losing the scent made crosswind casts and thus located the female. Downwind casts were rare. In still air males approached females from below. Visual stimuli seemed to induce mating behaviour.

In 1948, the Mississagi region of northern Ontario was swept by a niajor conflagration that began on May 25 and which, because of dry weather conditions, was not brought under control until July 23. When the fire had been extinguished, it was found to have spread over 57 townships, or 281,388 acres in all. Officers of the Ontario Department of Lands and Forests estimated that approximately 75 per cent of the fire area bore mature stands of eastern white pine (Pinus strobus L.), red pine (P. resinosa Ait.) and jack pine (P. banksiana Lamb.). Salvage operations began immediately in an effort to save this vast amount of valuable timber.

The initiation of the pupal diapause of the apple maggot, Rhagoletis pomonella (Walsh), was found to be regulated by photoperiod and temperature. The stages of R. pomonella sensitive to these two regulatory factors were demonstrated to be the larva in the case of photoperiod and the larva and pupa in the case of temperature. Measurements with a highly sensitive photocell revealed that enough light passes through the skin and pulp of an apple to permit the response of the larvae to photoperiod to be direct. Diapause initiation was found to be independent of the effect of photoperiod or temperature on the adults and eggs and independent of the amount or type of larval food (apple or artificial).

Where larvae and pupae were reared at 28°C and a photoperiod of 17 or 19 hours of light per 24-hour day, 1% of the pupae completed development in 23 days, 50% in 28 days, 75% in 30 days, and 100% in 64 days. These were the only regimes tested at which there was 100% non-diapause development, a finding which is directly applicable to continuous laboratory rearing of the apple maggot. Irrespective of temperature, diapause was induced in more than 50% of the pupae at a larval photoperiod of 11 hours. Even where larval photoperiod was favorable for 100% non-diapause development (17 or 19 hr), diapause was induced in more than 25% of the pupae if larval and pupal development occurred at 23°C and in a larger percentage if larval and pupal development occurred at 19°C.

These findings are helpful in elucidating those conditions in nature under which a second generation of R. pomonella occurs.

Combinations of Bacillus thuringiensis Berliner subspecies kurstaki and Beauveria bassiana (Balsamo) Vuillimen formulated on granules were applied separately and in combination to field corn to suppress larval populations of the European corn borer, Ostrinia nubilalis (Hübner). Research was conducted in 2 separate years. Laboratory-reared O. nubilalis eggs or larvae were placed on the plant during either the whorl stage (V6) or the pollen-shedding stage (R1) to simulate first- and second-generation O. nubilalis oviposition periods, respectively. Efficacy was determined by measuring the length of European corn borer tunnels in the corn stalk at harvest time. In the 1st year, first generation, and second generation (of 2nd year) B. thuringiensis and B. bassiana alone and in combination caused significant reductions in tunneling compared with that in the check populations. There were no significant differences in tunneling between any treatments in the second-generation study of year 1. Bacillus thuringiensis and B. bassiana were independent of each other in their suppression of insects. Tunneling by the naturally occurring second-generation larvae (year 2) was recorded to determine if B. thuringiensis and B. bassiana applied in the V6 stage persisted in the plant. Pith samples were excised from nodal plates 7–10 of the corn stalk to determine the incidence of B. bassiana. There was a significant correlation (r = −0.376) (P≤0.05) between the occurrence of B. bassiana in the corn plant and tunneling by second-generation larvae. These data indicate that B. bassiana placed in the whorl of the corn plant may provide season-long suppression of O. nubilalis.

A model is presented which describes the effect of sterile male release on a wild population. This model is not subject to restrictions, such as equal competitiveness between normal and sterile males and sperm nor to insect species whose females mate only once. The model is an approximation as it assumes constancy in several dynamic population variables. However, it has application in determining the approximate effects of sterile male release and in decisions on the number of sterile males required for release programs. It also has uses in ecological research.

Tarsi of male Colorado potato beetles adhere to glass and plastic surfaces limiting locomotion greatly. This is not observed with females. Scoop-like tarsal hairs present only in males are responsible for the adherence. The effect of this morphological difference on toxicological or behavioral research conducted in glass or plastic cages is discussed.

The flight capacity (duration and velocity) is an important phase of the flight behaviour of economically significant insects such as the Douglas-fir beetle, because it influences the feasibility of control or preventive measures which might be considered. An understanding of the flight capacity and how it varies in relation to environmental factors is necessary to evaluate the beetles' power of dispersal under different seasonal conditions. This would help to detect new areas of infestation by directing or narrowing the search. It also would help evaluation of the hazard at hand in timber surrounding the infestation and be a further aid in determining the size of areas of sanitation required around the comparatively beetle-free areas needed for special purposes, such as parks.

Rove beetle species and their pitfall trap abundance were studied in red spruce (Picea rubens Sarg.; Pinaceae) stands in the Acadia Research Forest, New Brunswick, Canada, in 1999. The study yielded over 5000 specimens representing 134 species in 11 subfamilies of Staphylinidae. Of these, 58 species represent new distribution records for New Brunswick (NPR), including 15 new distribution records for Canada (NCR), 6 new species, and 4 synonyms, as follows: Omaliinae, 3 species; Proteininae, Proteinus pseudothomasi Klimaszewski sp. nov. (NCR, NPR) and P. acadiensis Klimaszewski sp. nov. (NCR, NPR); Tachyporinae, 3 species; Trichophyinae, 1 species; Aleocharinae, 33 species, including Atheta capsularis Klimaszewski sp. nov., A. brunswickensis Klimaszewski sp. nov., A. pseudocrenuliventris Klimaszewski sp. nov., Oxypoda lacustris Casey (NPR) [= O. bradorensis Lohse syn. nov., O. egestosa Casey syn. nov., O. lassula Casey syn. nov., and O. optiva Casey syn. nov.], and Pella gesneri Klimaszewski sp. nov.; Oxytelinae, 3 species; Paederinae, 3 species; and Staphylininae, 10 species. The new species or known species representing new records for Canada are presented here with a short diagnosis, habitus images, and genital illustrations to help with identification. The habitus images and most genital illustrations are presented here for the first time for these species.

Ten species of predatory coccinellids representing seven genera were reared from the first-instar larva to the adult stage on dry powdered aphids. Dry pea aphids, Acyrthosiphon pisum (Harr.), and corn aphids, Rhopalosiphum maidis (Fitch), were both superior to bean aphids, Aphis fabae Scop., for growing coccinellid larvae. Though Anatis mali Auct. grew equally well on A. pisum and R. maidis, the larvae generally lived longer when starved after feeding on R. maidis. Dry aphids were as good as living aphids for growing A. mali and Coleomegilla maculata lengi Timberlake. C. maculata grew as well in darkness as in light, and an aphid–pollen mixture was superior to either component alone. Three generations of C. maculata were reared on a yeast diet and this diet is the most promising food for use to supplement natural foods in the field. An arrangement of coccinellid species on the basis of their food specificity does not correspond to the current phylogenetic arrangement, as the taxonomically primitive tribe Coccinellini contains both generalized and selective feeders.

The adults, mummies, and final-instar larvae of the eight hymenopterous parasites of the pea aphid, Acyrthosiphon pisum (Harris), in Eastern Canada are described and illustrated. The history, synonymy, and biology of each species, and the problems of species differentiation in two of the genera, Aphidius and Praon, are discussed. Keys are given to separate the adults, mummies, and cast skins of the last larval instar.

Trichogramma minutum Riley entered diapause, in the prepupal stage, in eggs of Lambdina fiscellaria fiscellaria Guenée held at 15°C, 12L:12D, but failed to do so in eggs of Ephestia kuehniella (Zeller), Sitotroga cerealella (Olivier), or Choristoneura fumiferana (Clemens) held under these conditions. The parasitoids emerged without diapause from eggs of all host species held at 25°C, 16L:8D, indicating a role of temperature or photoperiod, or both, in the diapause of the parasitoids in eggs of L. fiscellaria held at 15°C, 12L:12D. Percentage emergence of parasitoids from eggs of L. fiscellaria was virtually the same (>80%) after passing the winter outdoors or after approximately 3 months at 2 °C in the laboratory as it was when reared indoors in this host at 25°C, 16L:8D. Emergence of T. minutum was very poor (<20%) after long-term, low-temperature storage in eggs of C. fumiferana, E. kuehniella, or S. cerealella. Apparently, T. minutum must parasitize diapause host eggs in order to enter diapause, and good survival after long-term low-temperature storage is possible only when T. minutum is in diapause. Trichogramma minutum will enter diapause in L. fiscellaria after 14 days at 15°C, 12L:12D, but the parasitoids need a period of storage at 2°C, 0L:24D for a high percentage of emergence to happen. Over 50% emergence was recorded for T. minutum, held for 300 days in eggs of L. fiscellaria.

The recent introduction of the concept of refuge areas for the management of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera : Chrysomelidae), on resistant potato highlighted the existence of important gaps in our knowledge and understanding of this pest's movement within and between habitats. The objective of this review is to synthesize the information available for the benefit of crop managers and to identify subject areas in need of additional research. A traditional, somewhat encyclopedic, review of the old and recent literature on research methods, basics of flight and walking, as well as abiotic and biotic conditions for dispersal, revealed a considerable volume of information accumulated since the early 1900s. There is a consensus on the role of abiotic factors on flight and walking, but a better understanding of the biotic factors will be required before the variability of the dispersal response can be fully explained or predicted. Cybernetic models of orientation proposed in the literature were pulled together into a schematic representation of the orientation process in walking L. decemlineata. The model begins the integration of the different conditions and underlying suggested mechanisms responsible for the orientation of the walking beetle. There is remarkably little information on the orientation of potato beetles during flight. Finally, the seasonality of walking and flight dispersal is reviewed in relation to the host habitat and overwintering sites.

Stands of trembling aspen in Manitoba and Saskatchewan are frequently attacked by the forest tent caterpillar, Malacosoma disstria Hbn. The recent history of attack is reviewed in this paper to determine if there is evidence of a consistent pattern of outbreaks and if the latest of these had any appreciable effect on aspen stands in the two provinces.

Of the 21 Nearctic species of Pyrobombus Dalla Torre 11 are known to occur in southern Alberta. Distribution, macrohabitat, microhabitat, and period of nest establishment of the 11 species are compared. The behavioral patterns of camouflaging entrances to underground and false-underground hives, gathering material for nests, constructing first- and succeeding-brood egg cells, producing second-generation colonies, storing honey and pollen and producing wax, superseding intra- and inter-specifically, and mating and hibernating are compared both intra- and inter-subgenerically. Most of the behavioral patterns were common to all southern Alberta species of Pyrobombus; some were common only to certain species indicating a close relationship between these species, and one pattern was common to species in two subgenera but to only 4 of the 11 species of Pyrobombus. Thus, evolutionary trends were indicated. The enemies Psithyrus spp., Volucella bombylans (L.), and inclement weather are discussed.