Urine of male house mice, Mus musculus, is known to have primer pheromone effects on the reproductive physiology of female mice. Urine-mediated releaser pheromone effects that trigger certain behavioral responses are much less understood, and no field studies have investigated whether urine deposits by male or female mice, or synthetic mouse pheromone, increase trap captures of mice. In field experiments, we baited traps with bedding soiled with urine and feces of caged female or male mice, and recorded captures of mice in these and in control traps containing clean bedding. Traps baited with female bedding preferentially captured adult males, whereas traps baited with male bedding preferentially captured juvenile and adult females, indicating the presence of male- and female-specific sex pheromones in soiled bedding. Analyses of headspace volatiles emanating from soiled bedding by gas chromatography/mass spectrometry revealed that 3,4-dehydro-exo-brevicomin (DEB) was seven times more prevalent in male bedding and that 2-sec-butyl-4,5-dihydrothiazole (DHT) was male-specific. In a follow-up field experiment, traps baited with DEB and DHT captured 4 times more female mice than corresponding control traps, thus indicating that DEB and DHT are sex attractant pheromone components of house mouse males. Our study provides impetus to identify the sex attractant pheromone of female mice, and to develop synthetic mouse pheromone as a lure to enhance the efficacy of trapping programs for mouse control.

Foraging animals use diverse cues to locate resources. Common foraging cues have visual, auditory, olfactory, tactile or gustatory characteristics. Here, we show a foraging herbivore using infrared (IR) radiation from living plants as a host-finding cue. We present data revealing that (i) conifer cones are warmer and emit more near-, mid- and long-range IR radiation than needles, (ii) cone-feeding western conifer seed bugs, Leptoglossus occidentalis (Hemiptera: Coreidae), possess IR receptive organs and orient towards experimental IR cues, and (iii) occlusion of the insects' IR receptors impairs IR perception. The conifers' cost of attracting cone-feeding insects may be offset by occasional mast seeding resulting in cone crops too large to be effectively exploited by herbivores.

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Females of the parasitoid wasp Glyptapanteles flavicoxis (Marsh) (Hymenoptera: Braconidae) deposit sex pheromone on substrate that elicits attraction and wing fanning in conspecific males. We tested the hypothesis that wing fanning sound induces a behavioral response from females which, in turn, affects the males’ orientation toward them. Females exposed to playback of the males’ wing fanning sound engaged in short flights, with sound characteristics different from those of the males’ wing fanning sound. In two‐choice bioassays, playback of the females’ flight sound attracted significantly more males than a silent control stimulus, and in combination with pheromone‐containing body extract of females it attracted more males than female body extract alone. Our data support the conclusion that the males’ wing fanning induces sound and visual reply signals from females that help males orient toward them.

Trapping brown rats is challenging because they avoid newly placed traps in their habitat. Herein, we report the identification of the sex pheromone produced by male brown rats and its effect on trap captures of wild female brown rats. Collecting urine- and feces-soiled bedding material of laboratory-kept rats and comparing the soiled-bedding odorants of juvenile and adult males, as well as of adult males and females, we found nine compounds that were specific to, or most prevalent in, the odor profiles of sexually mature adult males. When we added a synthetic blend of six of these compounds (2-heptanone, 4-heptanone, 3-ethyl-2-heptanone, 2-octanone, 2-nonanone, 4-nonanone) to one of two paired food-baited trap boxes, these boxes attracted significantly more laboratory-strain female rats in laboratory experiments, and captured ten times more wild female rats in a field experiment than the corresponding control boxes. Our data show that the pheromone facilitates captures of wild female brown rats.