The crucifer flea beetle, Phyllotreta cruciferae (Goeze), and the striped flea beetle, P. striolata (Fabricius) (Coleoptera: Chrysomelidae), are invasive pests to canola, Brassica napus (Linnaeus) (Brassicaceae), in North America. Understanding how temperature and predators influence flea beetle damage in canola is critical for improving current management strategies, yet these factors are rarely studied. We examined the prevalence (proportion of plants damaged), intensity (defoliation of damaged plants), and overall damage (mean defoliation = prevalence × intensity) caused by flea beetles on canola seedlings at different temperatures, plant densities, and with or without generalist predators. Flea beetles preferred to feed on the abaxial (undersides) of cotyledons rather than the typically assessed adaxial (top) side, regardless of temperature, and produced more stem and cotyledon damage at higher temperatures, regardless of the species. Predators Pardosa spp. (Araneae: Lycosidae) and Pterostichus melanarius (Illiger) (Coleoptera: Carabidae) reduced flea beetle abundance and the intensity of cotyledon defoliation. Pterostichus melanarius also reduced overall stem damage, whereas Pardosa spp. reduced stem damage intensity. Under constant flea beetle densities, canola sustained less damage at a higher plant density. These results suggest that reducing the number of flea beetles per seedling, through predation or higher plant density, may help reduce Phyllotreta damage to canola.

Lobesiodes euphorbiana (Freyer) (Lepidoptera: Tortricidae), commonly known as the spurge leaf tying moth, was intentionally introduced into Canada in the 1980s as a biocontrol agent for leafy spurge, Euphorbia virgata Waldstein and Kitaibel (Euphorbiaceae). The moth has never been reported in the United States of America, where it was not approved for release as a biocontrol agent. Here, we report the first records of L. euphorbiana in Montana and North Dakota, United States of America.

Climate change affects not only temperatures but also rainfall patterns, which can either accentuate or mitigate the effects of warming on water stress in terrestrial insects. Water stress is more likely to affect eggs and larvae due to their small size. Hemlock looper (Lepidoptera: Geometridae) overwinters as eggs, and first-instar larvae must move to settle on host trees in the spring. Their survival depends both on their energy and water reserves that remain after overwintering and on the abiotic conditions present each spring. The effects of humidity (40, 60, and 80%) on the hatching success, time to hatch, and lifespan of unfed first-instar hemlock looper larvae were assessed at two temperatures, at 10 °C and at 22 °C. Lower humidity levels reduced hatching success and increased time to hatch, suggesting that humidity modulates development. On the other hand, higher temperatures reduced hatching success and time to hatch. The survival probability of unfed first-instar larvae was not influenced by ambient humidity but was longer for larvae from eggs reared at high humidity and 10 °C, suggesting that the physiological state of larvae at the time of hatching influences their survival. The ecological significance of these results and how they can influence our management tools are discussed.

Growing environmental concerns and the rise of pesticide resistance have prompted a critical need to develop alternatives to synthetic chemical insecticides. In this context, mineral-based products offer a promising solution for integrated pest management. This study examines the potential of a granite dust product as a control agent for two-spotted spider mites, Tetranychus urticae Koch (Acariformes: Tetranychidae), on grapevines, Vitis spp. (Vitaceae). Using two-choice repellency, repulsiveness, and no-choice bioassays involving substrate, foliar, and combined applications, the dust was found to effectively deter mites from moving from control leaves to treated leaves in repulsiveness tests; however, in repellency tests, some but not all mites moved from treated leaves to control leaves. Significantly higher mite mortality was observed across all dust treatments in both bioassays than in control treatments, suggesting that contact exposure to the dust and potentially the accumulation of silica in cell walls in plants treated with rock dust as a substrate amendment could render the cell walls resistant to piercing by spider mite mouthparts. The findings improve the understanding of this product’s potential for pest management.

Haskap, Lonicera caerulea Linnaeus (Caprifoliceae), is an emerging crop in Nova Scotia, Canada, that relies on cross-pollination for fruit production. In 2016 and 2017, we assessed the activity of honey bees, Apis mellifera Linnaeus (Hymenoptera: Apidae), in haskap orchards and compared this with native bumble bees, Bombus spp. (Hymenoptera: Apidae), while also documenting the early season wild bee community and potential of nesting boxes to support cavity-nesting bees. We found that haskap orchards in southern Nova Scotia support a diverse pollinator community. Andrena (Hymenoptera: Adrenidae) spp., A. mellifera, Bombus spp., and Lasioglossum spp. (Hymenoptera: Halictidae) comprised more than 75% of individuals captured in pan traps, but only A. mellifera and Bombus spp. were frequently observed on haskap blossoms. Honey bees and bumble bees deposited equal amounts of pollen on haskap stigmas, but bumble bees visited threefold more flowers per minute and visited both flowers of the haskap inflorescence more than twice as often as honey bees. Uptake of cavity-nesting bees into nesting boxes was relatively poor, and as many parasites (mostly Sapygidae) were collected from nesting boxes as bees. These results suggest honey bees and bumble bees are the best pollinators for haskap production in Nova Scotia.

Although insect pollination has been shown to enhance yields of soybean, Glycine max (Linnaeus) Merrill (Fabaceae), the lingering misconception among growers that soybean does not benefit from insect pollination hinders the adoption of pollinator-friendly practices. As such, identifying the wild pollinators visiting soybean flowers can help raise awareness of their importance in soybean production. We surveyed wild bees and wasps visiting soybean flowers and carrying soybean pollen in an extensive field crop region of southeastern Canada (Ontario and Quebec). Insects were hand-netted from 19 soybean fields while they actively foraged on soybean flowers, and their corbicular or scopal loads and body surfaces were screened for soybean pollen. A total of 81 insects (77 wild bees and four wasps), representing 18 bee and four wasp species, were collected. The majority (91.4%) carried soybean pollen, indicating a potential role in soybean pollination. Generalist bumble bees and ground-nesting bees were the most common, suggesting that management practices that support these two groups are likely to be particularly relevant for growers in Canada.

Shorter, warmer winters linked to climate change are inviting the northwards expansion of mosquito species (Diptera: Culicidae) and the pathogens they vector. Monitoring can play an important role in helping to mitigate the health impacts of mosquito-borne disease due to changes in regional mosquito species composition. To update the inventory of mosquito species currently residing in Nova Scotia, we sampled adult mosquitoes from 60 locations using Centers for Disease Control and Prevention light traps and collected mosquito larvae from 232 water sources across nine ecozones from May to October in 2021 and 2022. Of the 12 652 mosquitoes collected, we identified 35 species, including eight species not previously recorded in the province: Aedes aurifer (Coquillett), Aedes decticus Howard et al., Aedes pionips Dyar, Aedes hendersoni Cockerell, Aedes sticticus (Meigen), Culiseta minnesotae Barr, Culiseta melanura (Coquillett), and Culex salinarius Coquillett. We have also observed the province-wide expansion of Aedes japonicus (Theobald) since the species’ first detection in Nova Scotia in 2007. Overall, vector species are being detected more frequently in Nova Scotia, highlighting potential changes in disease dynamics as climate change progresses and furthering the need for continued monitoring.