Artificial Light at Night Reduces Flashing in Photinus and Photuris Fireflies During Courtship and Predation

J Insect Behav (2024) 37:49–57 https://doi.org/10.1007/s10905-024-09849-8 RESEARCH Artificial Light at Night Reduces Flashing in Photinus and Photuris Fireflies During Courtship and Predation Juan S. Hillón‑Salas · Juan D. Pineda‑Dueñas · Ana M. Romero‑Chacón · Juliana Fonseca‑Tellez · Manuela Cardona‑Restrepo · Sofía C. Garrido‑Villegas · Diego Mejía‑Tovar · Camilo Arenas‑Ríos · Laia Gaitán‑Botero · Zulma S. Barón‑Garzón · Andrés F. Robayo‑Salek · Harold Pulido‑Guarín · Juan J. Ovalle‑Barrera · Anyi D. Macías‑González · Nicolás Bernal‑Guatibonza · Adriana A. Maldonado‑Chaparro Received: 10 May 2023 / Revised: 7 March 2024 / Accepted: 11 March 2024 / Published online: 11 April 2024 © The Author(s) 2024 Abstract Artificial light at night (ALAN) affects species-specific communication in a wide range of nocturnal species, including fireflies (Lampyridae). Fireflies rely on bioluminescent signals for communicating. In this study, we conducted two manipulative field experiments to evaluate the effect of artificial light at night on the flashing activity of male and female neotropical fireflies during courtship and predation. Our results showed a significant reduction in the flashing activity of both males and females exposed to ALAN during courtship and predation. Remarkably, the effect of ALAN on male flashing Juan S. Hillón-Salas and Juan D. Pineda-Dueñas shared first author. Supplementary Information The online version contains supplementary material available at https://doi. org/10.1007/s10905-024-09849-8. J. S. Hillón‑Salas · J. D. Pineda‑Dueñas · A. M. Romero‑Chacón · J. Fonseca‑Tellez · M. Cardona‑Restrepo · S. C. Garrido‑Villegas · D. Mejía‑Tovar · C. Arenas‑Ríos · L. Gaitán‑Botero · Z. S. Barón‑Garzón · A. F. Robayo‑Salek · J. J. Ovalle‑Barrera · A. D. Macías‑González · N. Bernal‑Guatibonza · A. A. Maldonado‑Chaparro (*) Ecology and Animal Behavior Research Incubator Group, Department of Biology, Rosario University, Bogota, Colombia e-mail: H. Pulido‑Guarín Department of Biology, Military University, Bogota, Colombia activity seems to be independent of female flashing activity. In conclusion, ALAN disrupts bioluminescent intraspecific (courtship) and interspecific (predation) communication, which in turn could influence mating success, thus negatively affecting neotropical firefly populations in the long term. Our findings contribute to understanding the challenges faced by neotropical firefly communities in the presence of ALAN. Keywords Anthropogenic effects · communication disruption · intraspecific interaction · interspecific interaction · light pollution Introduction Light pollution is a threat to many nocturnal animal species. Globally, artificial light at night (ALAN) has been gradually increasing in brightness, with an average annual growth of 6%, although it can be as high as 20% in some countries (Hölker et al. 2010). This increment poses a problem for species adapted to respond to changes in light natural cycles (e.g., es daily, lunar, and seasonal) (Navara and Nelson 2007). ALAN disrupts the sensory information used by organisms to interpret and interact with their surroundings (Wakefield et al. 2015) and thus can affect trophic interactions (Maggi et al. 2020) and reproductive activities (Longcore and Rich 2004), which in turn can affect the fitness of individuals (Fobert Vol.: (0123456789) 13 50 et al. 2019). ALAN is one of the main factors driving the decline of nocturnal animal populations, especially those relying on visual communication such as Lampyridae (fireflies) (Owens and Lewis 2018; Lewis et al. 2020; Fallon and Heckscher 2021). Despite significant advances in our understanding of the ecological consequences of ALAN, its effects on the behavior of neotropical firefly species, is still poorly understood. Furthermore, the lack of information on this topic (but see Owens and Lewis 2018 for a review) is a major problem to be addressed given that fireflies are culturally, ecologically, and economically important. Fireflies are considered bioindicators of ecosystem health (Viviani 2001;Berge 2022) and have become an important nocturnal ecotourist activity (Lewis et al. 2021). ALAN can affect intra- and interspecific interactions in fireflies because they rely on bioluminescent signals (Owens and Lewis 2018). Bioluminescent cues (e.g., flashes) are specific to nocturnal species and provide information concerning species identity, sex, and mate quality (Lewis et al. 2020). For example, during courtship, the males of the genera Photinus and Photuris produce species-specific flash patterns while the females wait in the vegetation to respond back (Buschman 2016). During predation, female Photuris mimic the courting light patterns of Photinus to attract male Photinus (Zorn and Carlson 1978; Eisner et al. 1997). This suggests that ALAN can make the flashes harder to perceive and thus interfere with the ability to locate potential mates and prey. Adverse effects on courtship and predation patterns have been shown in previous studies in temperate areas (Costin and Boulton 2016; Firebaugh and Haynes 2016) but how generalizable is this phenomenon in neotropical areas is still not clear. Evaluating the ecological consequences of ALAN may become increasingly urgent in tropical countries where both population growth and increased urbanization are correlated with an increment in light pollution (Bennie et al. 2015). Fireflies are distributed worldwide but most of its diversity is in the Neotropics and the Asian Southeast (Lawrence and Newton 1995; cited in Vaz et al. 2023), and about halve of the species just in the tropics (Hogue 1993; cited in Stirr 2003). Despite this, neotropical fireflies have been less studied and much of what is known has been extrapolated from other North American species (Hogue 1993; cited in Stirr Vol:. (1234567890) 13 J Insect Behav (2024) 37:49–57 2003) including its responses to ALAN. One of the few neotropical studies experimentally investigating the effect of ALAN on fireflies showed that artificial light from lamps negatively impact the occurrence and flashing activity of Photinus sp. (Hagen et al. 2015). Although it is an important contribution the study did not consider LED-lamps–a broad spectrum energy-saving technology that is becoming widely popular (Elvidge et al. 2010) and, other behaviors such as mating, and predation which are sensitive to environmental light conditions. Thus, further experimental evidence for effects of ALAN is lacking. Here we evaluated the effect of ALAN on courtship and predation in neotropical fireflies of the genera Photinus and Photuris, two of the dominant genera in the neotropics (Hogue 1993; cited in Stirr 2003). Thus, we aim to test if, when exposed to artificial light from commercial white-light LED lamps (Halux) during activity hours, fireflies would reduce their flashing behavior. To investigate this, we designed two independent experiments: courtship and predation, created si (...truncated)