Nearly 65 years ago, D.G. Harcourt developed the first of 74 life tables of the diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), on the Central Experimental Farm in Ottawa, Ontario, Canada and at nearby sites. This work is cited whenever authors discuss the life history of the diamondback moth and its parasitoids in Canada. Since Harcourt’s study, climate change, urbanisation, and crop diversity may have altered the population dynamics of both the diamondback moth and its natural enemy community in the original study area. To follow up on Harcourt’s work, we used two approaches to build life tables to describe mortality factors in the field and the natural enemies attacking diamondback moth in Ottawa: destructive sampling of mature cabbage, Brassica oleracea Linnaeus (Brassicaceae), plants similar to Harcourt’s approach and a modern sentinel-based approach with an enemy exclusion cage treatment. After 65 years, the primary parasitoids attacking diamondback moth remained the same, although more parasitoid diversity was revealed by the destructive sampling technique. Total mortality and parasitism levels also remained similar. In one notable difference, we attributed more diamondback mortality to predation. Overall, however, diamondback moth population dynamics have changed little in Ottawa in the decades since Harcourt’s studies.

Southwestern Manitoba, a semiarid area subject to periodic droughts, was originally covered by a mixed prairie on light sandy soil. Settlement commenced on the completion of the land survey in 1890. By 1913 all the land was taken up and a cereal grain economy had developed. Soil drifting became a problem and was particularly severe during the drought years of 1929 to 1934. Local species of grasshoppers, Melanoplus sanguinipes (Fabricius), Melanoplus bivittatus (Say) and Camnula pellucida (Scudder) first became pests during a minor drought in 1901 and occurred in a severe outbreak in the major drought period. Recently abandoned fields suffered severe wind erosion and drift ridges of soil provided the most favorable egg laying sites for M. sanguinipes and to a lesser extent for M. bivittatus. The effect of slope of ground on egg deposition and grasshopper behavior in relation to temperature and moisture are recorded. Succulent, introduced weeds and cereal crops supplied abundant food. C. pellucida, a grass feeder, was favored by the planting of cereal crops adjacent to egg bed sites among Carex stenophylla Wahl., and Agropyron smithii Rydb. on the roadsides. Methods of farming designed to prevent wind erosion, the use of herbicides and the grading of roadsides have shown the possibilities of ecological management to reduce grasshopper increase.

A list is given of a total of 82 species of animals, mainly insects and mites, taken from the bracket fungus Polyporus betulinus (Bull.) Fr., growing on dead birch in Gatineau Park, Quebec.

The feeding behavior of adult Colorado potato beetles has been studied on leaflets from two clones of Solanum berthaultii Hawkes (PI473340, clones #1726 and #1729) and on S. tuberosum L. var. Norchip leaflets treated with leaf extract from S. berthaultii 1726. Treatment of S. tuberosum leaflet with leaf extract from S. berthaultii 1726 (0.075 mg/cm2 of leaflet) did not modify the behavior of adult Colorado potato beetles even if consumption was reduced. On S. berthaultii 1726, consumption and consumption rate were reduced, the frequency of the “moving” behavior increased, the frequency of the “resting” behavior decreased, and the frequency of the “feeding” behavior did not change compared with S. tuberosum. The antifeedant property of S. berthaultii 1726 probably was perceived during the sampling step of the feeding behavior and prevented continuous feeding.

The beetles avoided contact with S. berthaultii 1729 leaflets, less consumption occurred, the frequency of the “feeding” and “resting” behaviors was reduced, and the “moving” frequency increased in most cases. This suggested the presence of deterrents influencing host acceptance and initiation of feeding. On S. berthaultii 1726 and 1729, the frequency of some behaviors changed during the bioassay (2.5 h in duration), probably as a consequence of food deprivation.

Spalangia cameroni Perkins (Hymenoptera: Pteromalidae) is a pupal parasitoid of the Medfly, Ceratitis capitata (Wiedmann) (Diptera: Tephritidae), one of the principal pests of Spanish agriculture. Spalangia cameroni is a potential biocontrol agent for this pest if methods can be developed to mass-rear it effectively on C. capitata. Here, we report on the use of freeze-killed pupae of C. capitata to maintain a laboratory colony of S. cameroni, with a view to setting up a mass-rearing protocol. Realised fecundity, adult progeny, sex ratio, and superparasitism level were the principal parameters analysed. No significant differences were found in respect of these parameters between living or freeze-killed Medfly pupae used as hosts, although sex ratios showed a bias towards females in the case of freeze-killed pupae. Freeze-killed pupae were concluded to present the best option for the laboratory-rearing of S. cameroni, on account of ease of rearing, and avoidance of the emergence of Medfly adults.

Third-instar larvae of Phyllophaga (s.str.) ilhuicaminai Morón and Phyllophaga (Listrochelus) cuicateca Morón and Aragón are described. Larvae of P. ilhuicaminai were taken only from the roots of Limonium sinuatum (L.) Miller (Plumbaginaceae), an ornamental herb growing in fields near Atlixco, Puebla, Mexico. Larvae of P. cuicateca were found only on roots of Amaranthus hypocondriacus L. (Amaranthaceae) in fields near Altepexi, Puebla, Mexico. These larvae cause damage to the root system of both plant species under culture. Illustrations of diagnostic structures, a brief discussion on the differences between these larvae and other Phyllophaga Harris larvae, and a key to the Mexican larvae of the genus are included.

Extracts of eight species of freshwater vegetation were tested for toxicity against larvae of Aedes aegypti L. All extracts were found to be toxic. The same extracts and culture water from one of the species were also tested for their possible influences on the oviposition behaviour of A. aegypti. Extracts of six species repelled ovipositing females; one extract and the culture water attracted ovipositing females; and one extract type had no influence on the oviposition behaviour.

The eastern subterranean termite has been present in Ontario for over 25 years. Economic damage caused by the pest was first reported in 1944 and has increased considerably in the last decade, particularly in the Toronto region. Termites have also been found in four other localities in the Province.

We have developed a system for recording and quantifying animal behavior on artificial or natural substrates. The system is designed for subjects such as insects and mites with movement rates as high as 4 cm/min. The principle is the same as in automatic stage or sphere centering devices (Berg 1971; Kramer 1976; Thiery and Visser 1986), but the compensations are made manually by an observer who may also simultaneously enter codes for specific behaviors on a microcomputer keypad. Data files produced are analyzed or plotted using programs in SAS® (SAS Institute 1985a) or similar data analysis packages.

The larvae of certain Trichoptera are known to fashion into their cases structures to which a “ballast” function has been ascribed (Stuck, 1900; Buchner, 1905; Rousseau, 1921; Lloyd. 1921; Needham and Lloyd, 1937). Of forms living in the Ithaca, New York, region the cases of Stenophylax scabripennis, Halesus guttifer, Neophylax, and Goera calcarata are offered as examples. The term “ballast” has been used to imply a balancing as well as a weighting purpose depending upon the particular species under discussion. Rousseau (1921) in describing the general types of caddis cases says “…. in the absence of current, they (the cases) do not in general offer such adaptations as those which we find in the larvae living in moving water.

The Gulf of St. Lawrence aster, Symphyotrichum laurentianum (Fernald) G.L. Nesom (Asteraceae), a small annual halophyte endemic to disturbed and highly transient habitats in the Gulf of St. Lawrence, is classified as “threatened” by the Committee on the Status of Endangered Wildlife in Canada. Lepidopteran larvae that are predispersal seed predators of the Gulf of St. Lawrence aster are reported for the first time from populations in Prince Edward Island National Park. DNA barcoding was used to identify the seed predators tentatively as larvae of the casebearing moth Coleophora triplicis McDunnough (Lepidoptera: Coleophoridae), which is typically associated with a related halophyte, Solidago sempervirens L. (Asteraceae). These larvae were found to consume a large proportion of seeds from one of two aster populations in Prince Edward Island National Park and may be yet another risk to the survival of this threatened species.

Previous studies have shown that annual crops have different spider (Araneae) assemblages than adjacent relatively natural habitats, suggesting that spider recolonization of crops occurs via long-distance ballooning and that spider species in crops are mainly agrobionts. However, in perennial crops, e.g., apple (Malus domestica Borkhausen (Rosaceae)), which are subject to less physical disturbance than annual crops, overlap in spider species has been observed between tree foliage and adjacent habitats, suggesting that spiders colonize orchards from adjacent vegetation. The objective of this study was to compare the species composition of assemblages of foliage-dwelling spiders in apple orchards with that in adjacent deciduous forest and to determine whether spider assemblages in orchards are dominated by agrobiont species. Spiders were collected from four apple orchards and adjacent deciduous forest in southern Quebec from May until August 2004. The similarity of assemblages between the orchard and forest habitats was evaluated using nonmetric multidimensional scaling and multiresponse permutation procedures and spider species richness in the two habitat types was compared using rarefaction. Although spider species richness was higher in the forest than in the orchards, the composition of the spider assemblages in apple orchards was not significantly different from that in adjacent deciduous forest at three of the four sites. Therefore, adjacent deciduous forest, which is similar to orchards in vegetation structure and frequency of structural disturbance, is likely the main source of spiders found in apple orchards.

The forest tent caterpillar, Malacosoma disstria Hübner (Lepidoptera: Lasiocampidae), and large aspen tortrix, Choristoneura conflictana (Walker) (Lepidoptera: Tortricidae), are important pests of trembling aspen, Populus tremuloides Michx. (Salicaceae), in western Canada. Populations of both species can be monitored with sex pheromone-baited traps as part of an integrated pest management program. Moths captured in pheromone traps can also be used for ecological studies. Captured males of each species were examined to test the effect of population density, geographic region, and collection date on moth quality. Moth quality was assessed on the basis of wing area and level of infection with microsporidian parasites. The level of microsporidian infection of M. disstria was strongly dependent on geographic region but not on population density. Male M. disstria from high-density populations had smaller wings than males from endemic populations. Wing area of male M. disstria decreased throughout the flight period. Neither collection date nor microsporidian infection level affected wing area of male C. conflictana. Collection date also did not affect the level of microsporidian infection of C. conflictana. These data support pheromone trapping as a tool to detect microsporidian infections and examine their temporal and density-dependent effects on wing size in M. disstria and C. conflictana populations.

In 1966–67, the following fungi were isolated on Adelges piceae (Ratz.), a serious pest on fir trees in the Gaspé Peninsula: Fusarium larvarum, Cephalosporium coccorum, Entomophthora sp., Aspergillus fumigatus, Aspergillus nigra, Penicillium thomii, Penicillium sp., Cladosporium sp., Isaria farinosa, and Beauveria sp. F. larvarum showed more evidence of pathogenicity for Adelges, while C. coccorum was considered a facultative pathogen. There were not enough cases of infection by Isaria, Beauveria, and Entomophthora to determine their activity. Remaining species were saprophytic. Pathogenicity tests were conducted in the field with F. larvarum and C. coccorum. The fungi were introduced in the population by spraying or dusting, or by mites. However, a variety of external factors made it impossible to determine accurately the degree of virulence of these fungi for Adelges.

Nine species of Epidamaeus of subarctic western North America and extreme northeastern USSR are discussed. Six new species, Epidamaeus aborigensis, E. chukchi, E. floccosus, E. gilyarovi, E. koyukon and E. nasutus, are proposed; E. gibbofemoratus, E. hastatus and E. tenuissimus, previously described by Hammer, are redescribed.

The sunflower maggot is native to North America. It has been recorded from Maine and New Brunswick through Quebec to Alberta and California and as far south as New Mexico and Florida. It was collected by Criddle at Aweme, near Treesbank, Manitoba, in 1905 and is known to have been present in cultivated sunflowers in southern Manitoba since 1944. Heavy infestations have occurred since 1948.

Survivorship of the citrus blackfly was greatest at 25.6 °C and decreased in either direction from this temperature. A series of linear equations were derived to describe stadium length in thermal units for each development stage of the citrus blackfly and for the complete life cycle. There was no significant difference between the calculated stadium lengths and those observed in the field using linear thermal units.

The anatomy and functions of the male and female reproductive organs of Allothrombium lerouxi Moss are described in detail. In the male, the reproductive organs consist of paired testes, paired vasa diferentia, a median seminal vesicle, a median ejaculatory duct, bursa expulsatoria, a penis, and a median accessory gland; in the female, they consist of paired ovaries, paired oviducts, a median uterus and a vagina. The function of the parts in the male differs from that reported in other species of Trombidiformes, and in females fertilization takes place in the spongy epithelium of the uterus instead of in the oviducts as in oribatids. Females also lack a receptaculum seminis and accessory glands.

The underlying causes of grasshopper outbreaks in Western Canada are of interest both as an academic problem in insect population dynamics and as a practical problem in modern agriculture. Grasshopper populations reach their annual low point in early July when they are in the adult stage and increase sharply in the fall at the time of oviposition. Any factor that influences the grasshoppers during this period may have a marked effect on the outbreak of the following year. The relationship between grasshopper population numbers and proceeding fall temperatures may either control grasshopper populations directly by affecting their physiology or indirectly by affecting their parasites, predators, and diseases. Studies at the University of Saskatchewan aimed at solving this problem include investigation of the microclimate to which grasshoppers are subjected under field conditions, a survey of their feeding habits as shown by crop analyses, and a study of their oviposition behaviour. On the basis of available information an attempt is being made to predict future outbreaks at least 6 months in advance.

Within-tree models of Dendroctonus frontalis generation survival from attacking adults to emerging adults and survivorship from eggs to emergence were developed for five regions of the infested tree bole of Pinus taeda L. The generation survival model (GS) describes the number of D. frontalis/attacking adult as a function of time at a specific height. The form of the model is

YGS = 1.0 + C(1–e–20.0X)eA(1.0–X)B + ɛ.

The survival model (S) describes the number of D. frontalis/100 eggs as a function of time at a specific height. The form of this model is

YS = CeA(1.0–X)B + ɛ.

The generation survival model indicated that the rate of survival was primarily a function of generation development time, rather than position on the infested tree bole. The rates also varied in different sections of the tree depending on the initial egg/attacking adult population of D. frontalis. The emergence/attack ratios for the tree sections were slightly greater at the top and bottom than in the middle of the infested bole.

The survivorship curves, based on an initial cohort of 100 eggs, were similar for the various sections of the tree bole. Again, the rate of population change was primarily a function of developmental time, rather than position on the tree. The curves for the various tree sections were essentially the same.

The combined action of the various biotic and abiotic mortality agents acting in the different sections of the tree resulted in essentially uniform survivorship throughout the infested portion of the tree bole.