Light pollution is a driver of insect declines

Owens, Avalon C.S.; Cochard, Précillia; Durrant, Joanna; Farnworth, Bridgette; Perkin, Elizabeth K.; Seymoure, Brett

doi:10.1016/j.biocon.2019.108259

Cited by 280 publications

(219 citation statements)

References 187 publications

Supporting

Mentioning

200

Contrasting

Unclassified

Order By: Relevance

“…In conclusion, our results support the suggestion that light pollution is one cause of the global decline of glow-worms and fireflies, together with other human-induced environmental changes, such as climate change, habitat destruction, and the spread of insecticides [ 19 , 22 , 47 , 48 ]. The recorded lack of adaptive responses decreases success in mate attraction, which could reduce the reproductive output of populations.…”

Section: Discussionsupporting

confidence: 88%

Reproduction under light pollution: maladaptive response to spatial variation in artificial light in a glow-worm

et al. 2020

View full text Add to dashboard Cite

The amount of artificial light at night is growing worldwide, impacting the behaviour of nocturnal organisms. Yet, we know little about the consequences of these behavioural responses for individual fitness and population viability. We investigated if females of the common glow-worm Lampyris noctiluca —which glow in the night to attract males—mitigate negative effects of artificial light on mate attraction by adjusting the timing and location of glowing to spatial variation in light conditions. We found females do not move away from light when exposed to a gradient of artificial light, but delay or even refrain from glowing. Further, we demonstrate that this response is maladaptive, as our field study showed that staying still when exposed to artificial light from a simulated streetlight decreases mate attraction success, while moving only a short distance from the light source can markedly improve mate attraction. These results indicate that glow-worms are unable to respond to spatial variation in artificial light, which may be a factor in their global decline. Consequently, our results support the hypothesis that animals often lack adaptive behavioural responses to anthropogenic environmental changes and underlines the importance of considering behavioural responses when investigating the effects of human activities on wildlife.

show abstract

Section: Discussionsupporting

confidence: 88%

Reproduction under light pollution: maladaptive response to spatial variation in artificial light in a glow-worm

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Plausibly, in attraction-based trapping, a dilution effect could occur if an attractive stimulus from competing anthropogenic sources was itself increasing through time. For example, light trapping is used as a standard method for sampling moths, but in many rapidly urbanising areas, the number of competing anthropogenic sources of light has been increasing dramatically through time (Gaston et al, 2015;Owens et al, 2020). Thus, moth captures might decline through time simply because individuals are attracted elsewhere and are not as detectable in the monitoring traps.…”

Section: The Snapshot Effectmentioning

confidence: 99%

Interpreting insect declines: seven challenges and a way forward

Didham

Basset

Collins

et al. 2020

Insect Conserv Diversity

334

355

View full text Add to dashboard Cite

Many insect species are under threat from the anthropogenic drivers of global change. There have been numerous well‐documented examples of insect population declines and extinctions in the scientific literature, but recent weaker studies making extreme claims of a global crisis have drawn widespread media coverage and brought unprecedented public attention. This spotlight might be a double‐edged sword if the veracity of alarmist insect decline statements do not stand up to close scrutiny. We identify seven key challenges in drawing robust inference about insect population declines: establishment of the historical baseline, representativeness of site selection, robustness of time series trend estimation, mitigation of detection bias effects, and ability to account for potential artefacts of density dependence, phenological shifts and scale‐dependence in extrapolation from sample abundance to population‐level inference. Insect population fluctuations are complex. Greater care is needed when evaluating evidence for population trends and in identifying drivers of those trends. We present guidelines for best‐practise approaches that avoid methodological errors, mitigate potential biases and produce more robust analyses of time series trends. Despite many existing challenges and pitfalls, we present a forward‐looking prospectus for the future of insect population monitoring, highlighting opportunities for more creative exploitation of existing baseline data, technological advances in sampling and novel computational approaches. Entomologists cannot tackle these challenges alone, and it is only through collaboration with citizen scientists, other research scientists in many disciplines, and data analysts that the next generation of researchers will bridge the gap between little bugs and big data.

show abstract

“…In our study, we usually recorded the calls of the savanna nightjars at road intersection which have not only high levels of noise but also very bright artificial lights which attract phototactic insects 45 which consequently become hotspots for a nightjar's foraging. For nightjars, urban lights at night not only provide benefits because of the dense aggregations of insect prey but also because of the improved visibility to better catch these flying insects 46 . Therefore, territorial defense is likely intense around these hotspots of light and food.…”

Section: Discussionmentioning

confidence: 99%

Acoustic preadaptation to transmit vocal individuality of savanna nightjars in noisy urban environments

Liang

Walther

Jen

et al. 2020

Sci Rep

View full text Add to dashboard Cite

As urbanization has expanded dramatically, the impacts of urban noise on wildlife have drawn increasing attention. However, previous studies have focused primarily on diurnal songbirds and much less on nocturnal nonpasserines such as nightjars. The savanna nightjar has recently successfully colonized urban areas in Taiwan. Using 1925 calls recorded from 67 individuals, we first investigated the individual differences of the acoustic structures; and, for those acoustic variables with significant individual differences, we examined the correlation between the acoustic structures and the ambient noise levels. We then compared the transmission efficacy of vocal individuality among three sets of acoustic variables: all acoustic variables, noise-related variables, and noise-unrelated variables. Using seven artificial frequency-shifted calls to represent seven different individuals in playback-recording experiments, we also investigated the transmission efficacy of vocal individuality and variable accuracy in three different urban noise levels (high, medium, low). We found that all 30 acoustic variables derived from the acoustic structures demonstrated significant individual differences, and 14 frequency-based variables were negatively correlated with ambient noise levels. Although transmission efficacy was significantly affected by urban noise, individuality information was still transmitted with high accuracy. Furthermore, the noise-unrelated structures (which included the maximum frequency, the maximum amplitude frequency, and the mean frequency of the call) had a significantly higher transmission efficacy of vocal individuality than the noise-related variables (which included the minimum frequency, the frequency at the start and the end of the call) in both field observation and playback-recording experiments. We conclude that these noise-unrelated acoustic features may be one of the key preadaptations for this nocturnal nonpasserine to thrive so successfully in its newly adopted urban environment.

show abstract

Light pollution is a driver of insect declines

Cited by 280 publications

References 187 publications

Reproduction under light pollution: maladaptive response to spatial variation in artificial light in a glow-worm

Reproduction under light pollution: maladaptive response to spatial variation in artificial light in a glow-worm

Interpreting insect declines: seven challenges and a way forward

Acoustic preadaptation to transmit vocal individuality of savanna nightjars in noisy urban environments

Contact Info

Product

Resources

About