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Anthropogenic factors, such as artificial light at night (ALAN), are increasingly linked to significant modifications in animal behaviours, such as foraging or migration. However, few studies have investigated directly whether the presence of ALAN affects the ability to find a mate (mate location). One direct effect of the presence of ALAN is that it can create a light barrier in an otherwise dark environment. This may have significant behavioural implications for nocturnally active species if it affects their ability to respond to potential mates. Our study, using the acoustically orienting Australian black field cricket, Teleogryllus commodus, determined experimentally whether the presence of a fragmented light environment influenced movement patterns of virgin females and males. Moreover, given the importance of male song for reproductive outcomes in this species, we assessed simultaneously whether such behaviours were modified by the presence of a male attraction call. We found that while initiation of movement was slower in the presence of ALAN, the behavioural shifts associated with its presence were relatively small compared to the influence of a broadcast male attraction call. The response to the male attraction call was typically stronger for females than for males, but both males and females modified aspects of behaviour when it was present regardless of whether their immediate environment was fragmented by artificial light at night or not. Artificial light at night may alter subtle aspects of movement and mating behaviour in this species, but ultimately does not provide a barrier to movement or mate location.

Increasing evidence suggests that key fitness-related behaviours of animals related to courtship and mating may be disrupted by anthropogenic stressors, including artificial light at night (i.e. light produced from anthropogenic sources). Despite its ubiquity in urban habitats, we currently know very little about how artificial night lighting affects the reproductive behaviours of most animals. Our study examined the effects of chronic (lifetime) exposure to one of four ecologically relevant intensities of artificial light at night (0, 1, 10 or 100 lx at night) on courtship and mating behaviours and acoustic sexual signalling in a common nocturnal and crepuscular insect, the Australian black field cricket, Teleogryllus commodus. We found that lifetime exposure to brighter (10–100 lx) artificial light at night affected some aspects of courtship and mating behaviour: it influenced mate choice and mating efficiency in a sex-specific manner, but did not affect the multivariate structure of male courtship calls. Our results suggest that chronic exposure to bright light at night may affect some aspects of mate choice and reproductive behaviour in this common insect, and warrants further study across taxa.

The neuropeptide kisspeptin and its receptor are essential for activation of the hypothalamic-pituitary-gonadal (HPG) axis and regulating reproduction. While the role of kisspeptin in regulating the HPG axis in mammals has been well established, little is known about the functional ability of kisspeptins to activate the HPG axis and associated behavior in non-mammalian species. Here we experimentally examined the effects of kisspeptin on downstream release of testosterone and associated aggression and display behaviors in the side-blotched lizard (Uta stansburiana). We found that exogenous treatment with kisspeptin resulted in an increase in circulating testosterone levels, castration blocked the kisspeptin-induced increase in testosterone, and testosterone levels in kisspeptin-treated animals were positively related to frequency of aggressive behaviors. This evidence provides a clear link between kisspeptin, testosterone, and aggressive behavior in lizards. Thus, it is likely that kisspeptin plays an important role more broadly in non-mammalian systems in the regulation of reproductive physiology and related behaviors.

A variety of mechanisms are responsible for enabling an organism to escape a predatory attack, including behavioral changes, alterations in hormone levels, and production and/or secretion of toxins. However, these mechanisms are rarely studied in conjunction with each other. The Rough-skinned Newt ( Taricha granulosa ) is an ideal organism to examine the relationships between these mechanisms because its behavioral displays and toxin secretion during a predator attack are well documented and readily characterized. While we found no direct relationship between antipredator behavior and endogenous levels of corticosterone (CORT), antipredator behavior was inhibited when exogenous CORT and adrenocorticotropic hormone (ACTH) were administered, resulting in high circulating concentrations of CORT, indicating that CORT may play a role in mediating the behavior. There was no correlation between the animal’s toxicity and either CORT or behavior. The results of this study provide evidence that CORT plays an important, yet complex, role in the antipredator response of these amphibians.

Road-side aquatic ecosystems in North America are annually polluted with millions of tons of road deicing salts, which threaten the survival of amphibians which live and breed in these habitats. While much is known of the effects of NaCl, little is known of the second most-commonly used deicer, MgCl(2), which is now used exclusively in parts of the continent. Here we report that environmentally relevant concentrations of both NaCl and MgCl(2) cause increased incidence of developmental deformities in rough-skinned newt hatchlings that developed embryonically in these salts. In addition, we provide some of the first quantification of severity of different deformities, and reveal that increased salt concentrations increase both deformity frequency and severity. Our work contributes to the growing body of literature that suggests salamanders and newts are particularly vulnerable to salt, and that the emerging pollutant, MgCl(2) is comparable in its effects to the more traditionally-used NaCl.