Gerhard Gries

Simon Fraser University · Department of Biological Sciences

In central Canada, surveys for the three invasive (Palearctic) Agriotes species—A. obscurus, A. lineatus, and A. sputator—commonly collect A. pubescens, a North American native (Nearctic) click beetle (Coleoptera: Elateridae) that generally co-occurs with Nearctic A. mancus. Despite the abundance of A. pubescens on farmland, its life history and po...

Stable flies, Stomoxys calcitrans (Linnaeus) (Diptera: Muscidae), are common blood-feeding ectoparasites of cows and thus potential vectors of the skin-dwelling bacterium Staphylococcus aureus, a causal agent of bovine mastitis which inflicts udder inflammation in cows. Our objectives were to determine whether stable flies (i) are attracted to dise...

The hematophagous common bed bug, Cimex lectularius, is not known to transmit human pathogens outside laboratory settings, having evolved various immune defense mechanisms including the expression of antimicrobial peptides (AMPs). We unveil three novel prolixicin AMPs in bed bugs, exhibiting strong homology to the prolixicin of kissing bugs, Rhodni...

Stable flies, Stomoxys calcitrans (L.), are blood-feeding ectoparasites of cattle. Host-seeking stable flies respond to various cattle host cues, but a potential role of cattle breath gases [carbon dioxide (CO2), methane (CH4)] and cattle breath volatiles (acetone, isoprene, 2-butanone, 2-propanol, propionic acid, 3-methyl butyric acid, phenol), al...

Distressed western carpenter ants, Camponotus modoc , produce alarm pheromone and substrate‐borne vibrations. The alarm pheromone attracts nestmates but the effects of vibratory signals, or of bimodal pheromonal and vibratory signals, are not known. Worker ants of two Camponotus congeners reportedly stand still (“freeze”) or run fast in response to...

The common bed bug, Cimex lectularius, is an urban pest of global health significance, severely affecting the physical and mental health of humans. In contrast to most other blood-feeding arthropods, bed bugs are not major vectors of pathogens, but the underlying mechanisms for this phenomenon are largely unexplored. Here, we present the first tran...

Larval habitats of blood-feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), overlap with foraging sites of black blow flies, Phormia regina (Meigen) (Diptera: Calliphoridae). We tested the hypothesis that bacteria in blow fly excreta inform oviposition decisions by female stable flies. In laboratory 2-choice bioassays, we offered g...

An aqueous ant bait consisting of sucrose (4.55% w/v), essential amino acids (EAAs, 1%), and water is known to be highly appealing to multiple ant species throughout the foraging season. Here, we tested whether this bait, combined with boric acid as the lethal agent, has potential for control of pest ants. Specifically, we: (1) assessed bait lethal...

Following blood meals or questing bouts, hard ticks (Ixodidae) must locate moist off-host microhabitats as refuge. Soil-dwelling fungi, including entomopathogenic Beauveria bassiana (Bb), thrive in moist microhabitats. Working with six species of ixodid ticks in olfactometer bioassays, we tested the hypothesis that ticks avoid Bb. Contrary to our p...

Few studies have investigated the relative contribution of specific nutrients to momentary and season-long foraging responses by ants. Using western carpenter ants, Camponotus modoc, and European fire ants, Myrmica rubra, as model species, we: (1) tested preferential consumption of various macro- and micro-nutrients; (2) compared consumption of pre...

With increasingly fewer insecticides registered to control the larvae of pest click beetles (Coleoptera: Elateridae), integrative beetle management, including pheromone- and light-based trapping of adult beetles, must be explored as an alternative strategy. Here, we analyzed the spectral sensitivity and color preference of 9 elaterids across 6 gene...

Ticks spend most of their life inhabiting leaf litter and detritus where they are protected from sun but preyed upon by ants. Ants secrete chemical communication signals to coordinate group tasks such as nest defence. Ticks that avoid ant semiochemicals—as indicators of ant presence—would reduce predation risk by ants. We tested the hypotheses that...

Gravid female stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), oviposit in many types of organic substrates, including animal feces, but there is limited information as to which factors mediate attraction and oviposition. Here, we (1) tested effects of oviposition site moisture and odor on attraction and oviposition by flies, and (2) sel...

Targeted metabolomics has been widely used in pheromone research but may miss pheromone components in study organisms that produce pheromones in trace amount and/or lack bio-detectors (e.g., antennae) to readily locate them in complex samples. Here, we used non -targeted metabolomics—together with high-performance liquid chromatography–mass spectro...

Many haematophagous insects use the heat emitted by warm‐blooded animals as a cue for locating suitable hosts. Blood‐feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), are known to respond to visual and olfactory host cues. However, the effects of thermal host cues on the foraging behaviour of these flies remain largely unknown. He...

Female-female competition in animals has rarely been studied. Responses of females that compete context-dependently for mates and prey, and seek safety from predators, are ideally studied with web-building spiders. Cobwebs possess unique sections for prey capture and safety, which can be quantified. We worked with Steaoda grossa females because the...

Sex pheromone lures are effective tools for monitoring and potentially controlling populations of pest click beetles (Coleoptera: Elateridae). To date, these lures are genus‐specific (e.g., Limonius spp.) or species‐specific (e.g., Agriotes lineatus Linnaeus). However, if sympatric heterogeners were not to be repelled by each other's pheromones, tr...

The human skin microbiome reportedly contributes to the attraction of mosquitoes to human hosts. We tested the hypothesis that bovine skin microbes affect the attraction of blood-feeding stable flies, Stomoxys calcitrans, to their bovine hosts. Microbes were collected from a calf and adult cow, and subsequently isolated and identified by mass spect...

Foraging ticks reportedly exploit diverse cues to locate their hosts. Here, we tested the hypothesis that host-seeking Western black-legged ticks, Ixodes pacificus, and black-legged ticks, I. scapularis, respond to microbes dwelling in sebaceous gland secretions of white-tailed deer, Odocoileus virginianus, the ticks' preferred host. Using sterile...

The wheat wireworm, Agriotes mancus (Coleoptera: Elateridae), is a predominant elaterid pest species in the Nearctic region, with a life history and morphology similar to those of Agriotes obscurus , Agriotes lineatus and Agriotes sputator , three Palearctic pest elaterids invasive in North America. Here, we report the identification and field test...

Insects use their polarization-sensitive photoreceptors in a variety of ecological contexts including host-foraging. Here, we investigated the effect of polarized light on host foraging by the blood-feeding stable fly, Stomoxys calcitrans, a pest of livestock. Electroretinogram recordings with chromatic adaptation demonstrated that the spectral sen...

Bumble bee conservation focuses on supplementing floral resources. Yet, nesting site availability is linked to bumble bee abundance. As a supplement to natural nest sites, nest boxes could be deployed and baited with synthetic lures. As queen bumble bees reportedly establish colonies in abandoned rodent burrows, we hypothesized (1) that queen bumbl...

Analyses of pooled headspace volatiles from three commercial chili pepper, Capsicum spp., products by coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled GC-mass spectrometry (MS) revealed 10 compounds (β-pinene, γ-terpinene, linalool, 2-phenylethanol, cumin aldehyde, 1,3-menthadienal, eugenol, trans-β-caryophyllene, ca...

Female web-building spiders disseminate pheromone from their webs that attracts mate-seeking males and deposit contact pheromone on their webs that induces courtship by males upon arrival. The source of contact and mate attractant pheromone components, and the potential ability of females to adjust their web’s attractiveness, have remained elusive....

Common bed bugs, Cimex lectularius, can carry, but do not transmit, pathogens to the vertebrate hosts on which they feed. Some components of the innate immune system of bed bugs, such as antimicrobial peptides (AMPs), eliminate the pathogens. Here, we determined the molecular characteristics, structural properties, and phylogenetic relatedness of t...

The common bed bug, Cimex lectularius (Hemiptera: Cimicidae), is a blood-feeding ectoparasite of vertebrates, primarily humans. In contrast to many other hematophagous arthropods, such as kissing bugs, mosquitoes, sandflies, and ticks that intermittently seek blood meals from vertebrate hosts, C. lectularius does not vector disease-causing pathogen...

In western North America, sympatric Limonius click beetle species produce limoniic acid [(E)-4-ethyloct-4-enoic acid] as a sex pheromone component (L. canus (LeConte), L. californicus (Mannerheim)) or respond to it as a sex attractant (L. infuscatus (Motschulsky)). We tested the hypothesis that these three congeners maintain species-specificity of...

Ant colonies have vast and diverse nutritional needs but forager ants have limited mobility to meet these needs. Forager ants would accrue significant energy savings if they were able to sense and orient toward odor plumes of both carbohydrate and protein food sources. Moreover, if worker ants, like other flightless insects, had reduced olfactory a...

Synthetic sex pheromone lures are useful tools to monitor and control populations of adult click beetles (Coleoptera: Elateridae). However, sex pheromones for Agriotes click beetle species native to North America have yet to be identified. Here we report the identification and field testing of the sex pheromone of Agriotes ferrugineipennis. Headspa...

Four species of Tetramorium pavement ants are known to guide foraging activities of nestmates via trail pheromones secreted from the poison gland of worker ants, but the trail pheromone of T. immigrans is unknown. Our objectives were to (1) determine whether poison gland extract of T. immigrans workers induces trail-following behavior of nestmates,...

Sex pheromones are known for only a few major click beetle (Coleoptera: Elateridae) pests in North America. These pheromones could be used to monitor, as well as control, adult beetles. Our objective was to identify the sex pheromone of female Selatosomus aeripennis destructor (Brown), a predominant elaterid pest species in farmland in the Canadian...

An amendment to this paper has been published and can be accessed via the original article.

The cover image is based on the Research Article Cheese and cheese infusions: ecological traps for mosquitoes and spotted wing Drosophila by Daniel AH Peach et al., https://doi.org/10.1002/ps.6603. Image Credit: Sean McCann. The cover image is based on the Research Article Cheese and cheese infusions: ecological traps for mosquitoes and spotted win...

Unlike almost all hematophagous insects, common bed bugs, Cimex lectularius, are not known to transmit pathogens to humans. To help unravel the reasons for their lack of vector competence, we studied the time- and tissue-dependent expression of innate immune factors after blood feeding or immune activation through the intrathoracic injection of bac...

BACKGROUND Harnessing insect ecology for insect control is an innovative concept that seeks to exploit, among others, insect–microbe ecological interactions for improved control of pest insects. Microbe‐produced cheese odour attracts several dipterans, including host‐seeking mosquitoes, but this phenomenon has not been thoroughly explored for mosqu...

While it is well documented that insects exploit polarized sky light for navigation, their use of reflected polarized light for object detection has been less well studied. Recently, we have shown that the small white butterfly, Pieris rapae, distinguishes between host and non-host plants based on the degree of linear polarization (DoLP) of light r...

Ants select sustained carbohydrate resources, such as aphid honeydew, based on many factors including sugar type, volume and concentration. We tested the hypotheses (H1–H3) that western carpenter ants, Camponotus modoc, seek honeydew excretions from Cinara splendens aphids based solely on the presence of sugar constituents (H1), prefer sugar soluti...

Four species of Limonius wireworms (Coleoptera: Elateridae), L. californicus, L. canus, L. infuscatus and L. agonus, are serious crop pests in North America. Limoniic acid, (E)-4-ethyloct-4-enoic acid, has been reported as a sex pheromone component of female L. californicus and L. canus, and a sex attractant for male L. infuscatus. In the same stud...

The polyphagous invasive brown marmorated stink bug, Halyomorpha halys, reportedly discriminates among phenological stages of host plants. To determine whether olfaction is involved in host plant stage discrimination, we selected (dwarf) sunflower, Helianthus annuus, as a model host plant species. When adult females of a still-air laboratory experi...

An underlying assumption of optimal foraging models is that animals are behaviorally, morphologically, and physiologically adapted to maximize their net energy intake. Here we explored whether this concept applies to web-building spiders in a multi-trophic context. If a spider were to build her web next to herbivore-fed-on plants that signal the he...

Many ants prey on spiders, suggesting that web-building spiders may avoid micro-locations near ant colonies or frequented by foraging ants. Here we tested the hypothesis that ant-derived semiochemicals deter synanthropic spiders. To generate stimuli, we exposed filter paper for 12 h to workers of European fire ants, Myrmica rubra, black garden ants...

Foraging behavior of Brown Rats (Rattus norvegicus) is commonly thought to be guided by olfactory cues. Here we tested the hypothesis that foraging Brown Rats eavesdrop on bird vocalizations to locate prey. We recorded calls of nestling Starlings (Sturnus vulgaris) with microphones sensitive in the sonic and ultrasonic range, respectively, and comp...

As recently reported, light flashes of incident sunlight reflecting off the wings of in-flight dipterans serve as mate recognition signals. Mate location and mate selection behavior in the yellow fever mosquito, Aedes aegypti, take place in mating swarms but the mechanisms underlying swarm formation and long-range detection of females by males rema...

Deployment of lethal food baits could become a control tactic for the invasive European fire ant (EFA), Myrmica rubra L. (Hymenoptera: Formicidae), because foraging ants carry the lethal food to their nest and share it with their nest mates, ultimately causing the demise of nests. Our objective was to develop a food bait that elicits a strong forag...

Synthetic replica of rat pup, Rattus norvegicus, vocalizations reportedly increase captures of wild rats in traps baited with natural scent of adult female rats. Here we tested the hypotheses (1) that synthetic calls of house mouse pups, Mus musculus, increase captures of wild house mice in traps baited with synthetic sex pheromones of mice, and (2...

Background There is widespread interkingdom signalling between insects and microbes. For example, microbes found in floral nectar may modify its nutritional composition and produce odorants that alter the floral odor bouquet which may attract insect pollinators. Mosquitoes consume nectar and can pollinate flowers. We identified microbes isolated fr...

Wireworms, the larvae of click beetles (Coleoptera: Elateridae), are soil-dwelling insect pests inflicting major economic damage on many types of agricultural crops worldwide. The objective of this work was to identify the female-produced sex pheromones of the Pacific Coast wireworm, Limonius canus LeConte, and the sugarbeet wireworm, L. californic...

1. Aphids are capable of adapting to parasitoid pressure in the absence of sexual reproduction using epigenetically controlled polyphenism. Asexual lineages of aphids could thus become resistant to parasitoids over time and with repeated exposure, hampering biocontrol efforts that rely on parasitoid wasps. 2. Prior to this study, wing polyphenism a...

We tested the hypothesis that the "ecological trap" phenomenon (a mismatch between a habitat's perceived attractiveness and its actual quality, resulting in a population sink) is exploitable for pest control. We selected mosquitoes as modal organisms, because selection of an oviposition site by adult female mosquitoes in response to its perceived a...

Mammalian pheromones often linger in the environment and thus are particularly susceptible to interceptive eavesdropping, commonly understood as a one-way dyadic interaction, where prey sense and respond to the scent of a predator. Here, we tested the “counterespionage” hypothesis that predator and prey co-opt each other’s pheromone as a cue to loc...

While it is well documented that insects exploit polarized sky light for navigation, their use of reflected polarized light for object detection has been less well studied. Recently, we have shown that the small white butterfly, Pieris rapae , distinguishes between host and non-host plants based on the degree of linear polarization ( DoLP ) of ligh...

There is an ever increasing number of arthropod taxa shown to have polarization sensitivity throughout their compound eyes. However, the downstream processing of polarized reflections from objects is not well understood. The small white butterfly, Pieris rapae, has been demonstrated to exploit foliar polarized reflections, specifically the degree o...

Formicine ants in distress spray alarm pheromone which typically recruits nestmates for help. Studying the western carpenter ant, Camponotus modoc Wheeler (Hymenoptera: Formicidae), our objectives were to (1) determine the exocrine glands that contain alarm recruitment pheromone, (2) identify the key alarm recruitment pheromone components, and (3)...

Background There is widespread interkingdom signalling between insects and microbes. For example, microbes found in floral nectar may modify its nutritional composition and produce odorants that alter the floral odor bouquet which may attract insect pollinators. Mosquitoes consume nectar and can pollinate flowers. We identified microbes isolated fr...

The original version of this article unfortunately contained a mistake.

Males of widow spiders courting on the web of females engage in web-reduction behavior which entails excising a section of the web, bundling it up, and wrapping it with their silk. Males of the false black widow spider, Steatoda grossa, in European populations also produce stridulatory courtship sound which has not yet been studied in their invaded...

Female false black widows, Steatoda grossa (Araneae: Theridiidae), build energy-costly webs. We tested the hypotheses (H1, H2) that females prefer their own webs and the chemical extract of their own webs to those of conspecifics, and (H3) that mated females discern between their own egg sacs and those of conspecifics. In choice bioassays, females...

There is an ever increasing number of arthropod taxa shown to have polarization sensitivity throughout their compound eyes. However, the mechanisms underlying arthropod perception of polarized reflections from objects such as plants are not well understood. The small white butterfly, Pieris rapae, has been demonstrated to exploit foliar polarized r...

Trail pheromones deposited by ants lead nestmates to food sources. Based on previous evidence that the trail pheromone of the carpenter ant Camponotus modoc originates from the hindgut, our objective in this study was to identify the key component(s) of the pheromone. We collected C. modoc colonies from conifer forests and maintained them in an out...

Insect herbivores exploit plant cues to discern host and non-host plants. Studies of visual plant cues have focused on colour despite the inherent polarization sensitivity of insect photoreceptors and the information carried by polarization of foliar reflectance, most notably the degree of linear polarization (DoLP; 0-100%). The DoLP of foliar refl...

For a very long time, mosquitoes have been known or suspected to consume plant liquids. Recently eclosed mosquitoes cannot survive long without consuming sugary plant liquids that provide fuel for flight and enable blood‐feeding and mating. Populations of even highly synanthropic mosquitoes may not be able to persist without phytophagy, even when v...

Ants deposit trail pheromones that guide nestmates to food sources. We tested the hypotheses that ant community members (Western carpenter ants, Camponotus modoc; black garden ants, Lasius niger; European fire ants, Myrmica rubra) (1) sense, and follow, each other’s trail pheromones, and (2) fail to recognize trail pheromones of allopatric ants (pa...

Females of the false black widow, Steatoda grossa CL Koch (Araneae: Theridiidae), invest significant energy and time weaving cobwebs. We tested the hypothesis that S. grossa females select sites for their webs based, in part, on the presence of con‐ or heterospecific webs, sensing both physical and chemical web cues. In bioassays, we offered female...

The two subspecies of the small white butterfly, the European Pieris rapae rapae and the Asian P. r. crucivora, differ in wing colouration. Under ultraviolet light, the wings of both male and female P. r. rapae appear dark, whereas the wings of male P. r. crucivora are dark and those of females are bright. It has been hypothesized that these sexual...

As part of an ongoing program to identify sex attractant pheromone components that mediate sexual communication in yellowjacket wasps, a novel sesquiterpene was isolated from body surface extracts of virgin bald-faced hornet queens, Dolichovespula maculata. The gross structure of this sesquiterpene was proposed through microscale spectroscopic anal...

Inflorescence patterns of ultraviolet (UV) absorption and UV-reflection are attractive to many insect pollinators. To understand whether UV inflorescence cues affect the attraction of nectar-foraging mosquitoes, we worked with the common house mosquito, Culex pipiens and with two plant species exhibiting floral UV cues: the tansy, Tanacetum vulgare...

Plant essential oils (EOs) have been considered as spatial repellents to help disrupt the pathogen transmission cycle of mosquitoes. Our objective was to assess spatial repellency effects of EOs on the tropical yellow fever mosquito, Aedes aegypti (L.) (Diptera: Culicidae) and on local mosquito populations in coastal British Columbia (Canada). In l...

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.