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In the urban jungle, the sun dips below the skyline, painting the sky in shades of rich orange, red and pink before it turns inky black and starry. Slowly, the cacophony of nightlife begins singing its tune in the streets: car wheels whirring on roads, ambulances wailing, people laughing – every sound amplified in the cool night air. Meanwhile, dazzling streetlights try to outshine the night sky, certainly eclipsing the moon’s gentle glow. Bathing under these beams of light, you could pretend the day is upon you once again. Now imagine living this urban life, but as an owl, you are perfectly adapted, but not for this landscape, trying to hunt in a changing world. It seems like an impossible mission, but is this really the case?
Our world is becoming increasingly urbanised, with 8% of the total UK land area being urban.1 However, it isn’t all doom and gloom, and urbanisation isn’t a death sentence for our native wildlife. Although natural habitat is lost, wildlife is resilient and often able to return, adapting to our towns and cities. Take the red fox, for example, they are a common sight in urban areas, exploiting shelter and food waste, with over 37% of their diet being scavenged food!2 The red fox has become so adapted to urban life that their skull shape has even changed, with urban foxes having a wider, shorter muzzle than their rural counterparts, allowing them to forage on these new food sources.2
However, not all species are quite as adaptable to change, and urbanisation remains a key threat to biodiversity.3 Two key aspects of this threat are artificial light at night (also called ALAN) and anthropogenic noise, both of which can interfere with sensory perception. This may sound complex, but to break it down, imagine you are at a party: lights are flashing, the music is so loud you can feel the vibrations running through your body, and people are singing at the tops of their lungs. With all of these sensory inputs, it would be extremely difficult to have a casual conversation with somebody. I’m sure we’ve all been there, parties simply aren’t the place for a big catch-up! Similarly, nocturnal predators are adapted to hunt in quiet, dark conditions using subtle acoustic cues to locate their prey. As you can imagine, blaring traffic noise would make this a lot more challenging to do!
In addition to sensory overload, ALAN and anthropogenic noise can have other effects on nocturnal wildlife. Noise is associated with an increased perception of risk, which can cause stress, making animals abandon their typical home ranges, stop foraging and prevent communication with other individuals (our urban world is the party noise disrupting their catch-up, so to say). Moreover, ALAN can also confuse circadian and seasonal rhythms (these are the internal “body clocks” of animals, telling them the time of day or year). It’s no wonder they may not realise it’s nighttime when the streets are flooded with light from dazzling streetlamps! However, there is a silver lining… ALAN can actually improve foraging efficiency in some species, as these light sources attract invertebrates, creating an all-you-can-eat buffet for our insectivorous wildlife!4
With this in mind, does life in the urban jungle really ruffle some feathers, or is it simply a breeze? This is the question a recent study aimed to answer, focusing on hunting behaviour in the majestic tawny owl…
Hunting for the answer
To test the effects of anthropogenic noise and ALAN, researchers tested the hunting abilities of 38 captive tawny owls under four different conditions. These conditions were:
- Dark and silent (natural, control conditions)
- Dark with traffic noise (testing the effects of anthropogenic noise)
- ALAN and silent (testing the effects of ALAN)
- ALAN and traffic noise (testing the combined effect of ALAN and anthropogenic noise)
Under all four of these conditions, they presented the owls with visual and acoustic cues of prey. The visual cue was the body of a dead mouse tied to fishing wire, which was pulled back and forth by the experimenter to mimic natural movement – what a job to have! Whereas the acoustic cue was a sound recording of rustling in undergrowth. These two cues were presented to the tawny owls four times for thirty seconds each time.
As these experiments were conducted at night, they used infrared cameras to record the behaviours of the owls, using three measures to quantify hunting ability. Firstly, they recorded responsiveness (whether or not the owl reacted to the prey cue). Secondly, they recoded the latency of response (how long it took until the owl first reacted). Finally, they recoded the total duration of response (the total time spent responding to the cues).
What did they find?
As expected, ALAN and anthropogenic noise did in fact ruffle the owl’s feathers, decreasing their responsiveness to prey cues. However, individually, these disturbances only affected responses to the acoustic cues (the sound of rustling in the undergrowth, as opposed to the visual cue of the mouse). In contrast, responses to the visual cues were only reduced when ALAN and anthropogenic noise were combined, causing greater sensory pollution. What’s even more interesting is that this combination of ALAN and anthropogenic noise unexpectedly buffered the negative effects on responsiveness to acoustic cues! This means that the owls responded more to the sounds of prey when there was traffic noise, when it was light, compared to when it was dark. From this, the researchers concluded that the owls are able to switch their hunting technique depending on the type of sensory pollution, relying more on visual cues where needed.
Luckily, owls have both scotopic and photopic vision. This means that they can see both in dim light conditions at night (scotopic vision) and can discriminate colours and UV during the day (photopic vision). This reduces the negative effects of ALAN and enables them to make this switch to rely more on sight-oriented hunting. Moreover, it’s also theorised that ALAN may increase hunting effort, which would further increase responsiveness to prey cues. This increase in hunting effort is evidenced in natural conditions during brighter phases of the lunar cycle, because prey are more vigilant during these times. Perhaps ALAN may be having the same effect as the moon, causing increased responsiveness to prey!
So, the urban environment does negatively impact the hunting abilities of owls, but they are able to adapt their behaviour, altering hunting effort and switching their reliance on different prey cues depending on the type of sensory pollution. They certainly are wise owls!
How to make urban life “a hoot” for wildlife
Of course, we aren’t able to make our urban areas dark and silent like they once were, but there are some changes we can make to support our urban wildlife. These resources provide some further reading and guidance on making our streets a paradise for nature:
https://www.nhm.ac.uk/discover/urban-wildlife.html#helpwildlife – Useful information about wildlife locally, nationally and globally and what we can do to give a helping hand
https://www.wildlifetrusts.org/where_to_see_urban_wildlife – A useful resource jampacked with information about where you can spot urban wildlife in your local area
https://www.bbc.co.uk/iplayer/episode/m002hzg7/wild-london – Wild London is a fantastic series narrated by David Attenborough on the wildlife wonders in London
Article written by Sophie Nash
Primary paper:
Passarotto, A., Morosinotto, C., & Karell, P. (2025). Experimental noise and light pollution alter prey detection in a nocturnal bird of prey. Journal of Animal Ecology, 94, 1398–1409. https://doi.org/10.1111/1365-2656.70062
Other references:
- Office for National Statistics (ONS), released 5 December 2025, ONS website, statistical bulletin, UK natural capital accounts: 2025. Available at: https://www.ons.gov.uk/economy/environmentalaccounts/bulletins/uknaturalcapitalaccounts/2025
- J. Parsons, et al., Skull morphology diverges between urban and rural populations of red foxes mirroring patterns of domestication and macroevolution. https://doi.org/10.1098/rspb.2020.0763
- Christopher N. Johnson, et al., Biodiversity losses and conservation responses in the Anthropocene. Science. 356, 270-275 (2017). DOI: 10.1126/science.aam9317 Available at: https://www.science.org/doi/10.1126/science.aam9317
- Rodríguez, A., Orozco-Valor, P.M. & Sarasola, J.H. Artificial light at night as a driver of urban colonization by an avian predator. Landscape Ecol36, 17–27 (2021). https://doi.org/10.1007/s10980-020-01132-3
