Streetlights -- particularly those that use white light-emitting diodes (LEDs) -- not only disrupt insect behavior but are also a culprit behind their declining numbers, a new study carried out in southern England showed Wednesday.
Artificial lights at night had been identified as a possible factor behind falling insect populations around the world, but the topic had been under-researched.
To address the question, scientists compared 26 roadside sites consisting of either hedgerows or grass verges that were lit by streetlights, against an equal number of nearly identical sites that were unlit.
They also examined a site with one unlit and two lit sections, all of which were similar in their vegetation.
The team chose moth caterpillars as a proxy for nocturnal insects more broadly, because they remain within a few meters of where they hatched during the larval stage of their lives, before they acquire the ability to fly.
The team either struck the hedges with sticks so that the caterpillars fell out, or swept the grass with nets to pick them up.
The results were eye-opening, with a 47 percent reduction in insect population at the hedgerow sites and 37 percent reduction at the roadside grassy areas.
"We were really quite taken aback by just how stark it was," lead author Douglas Boyes, of the UK Centre for Ecology and Hydrology, told AFP, adding the team had expected a more modest decline of around 10 percent.
"We consider it most likely that it's due to females, mums, not laying eggs in these areas," he said.
The lighting also disturbed their feeding behavior: when the team weighed the caterpillars, they found that those in the lighted areas were heavier.
Boyes said the team interpreted that as the caterpillars not knowing how to respond to the unfamiliar situation that runs counter to the conditions they evolved in over millions of years, and feeding more as a result to rush through their development.
The team found that the disruption was most pronounced in areas lit by LED lights as opposed to high-pressure sodium (HPS) lamps or older low-pressure sodium (LPS) lamps, both of which produce a yellow-orange glow that is less like sunlight.
LED lamps have grown more popular in recent years because of their superior energy efficiency.
The paper acknowledged the effect of street lighting is localized and a "minor contributor" to declining insect numbers, with other important factors including urbanization and destruction of their habitats, intensive agriculture, pollution and climate change.
But even localized reductions can have cascading consequences for the wider ecosystem, resulting in less food for the birds and bats that prey upon insects.
Moreover, "there are really quite accessible solutions," said Boyes -- like applying filters to change the lamps' color, or adding shields so that the light shines only on the road, not insect habitats.
ETX Studio
Sat Aug 28 2021
![LED streetlights contribute to insect population declines: Study LED streetlights contribute to insect population declines: Study](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2021-08/41630125346_led.jpg)
LED lamps have grown more popular in recent years because of their superior energy efficiency. Photography Joppi / Getty Images
![Malaysia kekal destinasi utama bagi pelaburan PTTEP - BMI Malaysia kekal destinasi utama bagi pelaburan PTTEP - BMI](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2021-02/81613025046_TBPelantarMinyak.jpg)
Malaysia kekal destinasi utama bagi pelaburan PTTEP - BMI
Malaysia akan kekal sebagai destinasi utama bagi pelaburan syarikat minyak nasional Thailand, PTT Exploration and Production (PTTEP), dalam jangka masa pendek dan panjang.
Jualan penyaman udara naik mendadak di negara Balkan
Menetap di negara sejuk, mereka tidak pernah terfikir memasang penyaman udara di dalam rumah memandangkan musim panas bukanlah setiap hari. Namun, cuaca panas melampau membuatkan mereka bertukar fikiran.
![Malaysia kecam sekeras-kerasnya pencerobohan ekstremis Zionis Israel ke atas Masjid Al-Aqsa Malaysia kecam sekeras-kerasnya pencerobohan ekstremis Zionis Israel ke atas Masjid Al-Aqsa](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2024-01/61706688348_wismaputra.jpg)
Malaysia kecam sekeras-kerasnya pencerobohan ekstremis Zionis Israel ke atas Masjid Al-Aqsa
Kerajaan Malaysia mengecam sekeras-kerasnya pencerobohan Masjid Al-Aqsa oleh ekstremis Zionis Israel pada 13 Ogos.
![Reda dengan pemergian anak walaupun bukan pengakhiran diharapkan - Ayah Nidza Afham Reda dengan pemergian anak walaupun bukan pengakhiran diharapkan - Ayah Nidza Afham](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2024-08/61723653359_TBMOKHTAR.jpg)
Reda dengan pemergian anak walaupun bukan pengakhiran diharapkan - Ayah Nidza Afham
Ayah kepada penyanyi dan Youtubers Muhammad Nidza Afham Mokhtar reda dengan pemergian anak lelakinya walaupun itu bukan pengakhiran yang beliau harapkan.
Ahli perniagaan diberkas, terlibat dalam aktiviti kumpulan mafia
Seorang ahli perniagaan Itali ditangkap di bandar Natal, Brazil pada selasa.
Giuseppe Bruno kini menghadapi tuduhan termasuk melakukan pemerasan dan pengubahan wang haram dan juga penglibatan bersama kumpulan mafia.
Giuseppe Bruno kini menghadapi tuduhan termasuk melakukan pemerasan dan pengubahan wang haram dan juga penglibatan bersama kumpulan mafia.
Srettha hormati keputusan mahkamah
Srettha Thavisin menghormati keputusan Mahkamah Perlembagaan Thailand yang memecatnya daripada jawatan Perdana Menteri.
Lahir empat hari lepas, bayi kembar maut angkara serangan rejim Zionis
Kembar lelaki diberikan nama Asser manakala Ayssel pula nama diberi buat kembar perempuan, kedua-duanya lahir pada 10 Ogos lepas.
Lelaki tikam ibu saudara direman tujuh hari
Seorang lelaki yang disyaki menikam ibu saudaranya di kepala dengan gunting, semalam direman selama tujuh hari hingga 21 Ogos ini.
PN senarai pendek tiga calon, akan diumum selepas PRK Nenggiri
Perikatan Nasional telah menyenarai pendek tiga calon untuk bertanding pada Pilihan Raya Kecil (PRK) Dewan Undangan Negeri (DUN) Mahkota yang dijadualkan berlangsung pada 28 September depan.
![10 cedera dalam kejadian reaktor kilang terbakar di Bintulu 10 cedera dalam kejadian reaktor kilang terbakar di Bintulu](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2024-07/41722145972_KebakaranGeneric.jpg)
10 cedera dalam kejadian reaktor kilang terbakar di Bintulu
Menurut PGOB kesemua mangsa yang cedera telah dikejarkan ke Hospital Bintulu untuk rawatan lanjut.
![Stadium Sultan Ibrahim tewaskan 19 pesaing raih anugerah stadium terbaik 2020 Stadium Sultan Ibrahim tewaskan 19 pesaing raih anugerah stadium terbaik 2020](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/https://img.astroawani.com/2020-02/81582324465_TBstadiumsultanibra.jpg)
Stadium Sultan Ibrahim tewaskan 19 pesaing raih anugerah stadium terbaik 2020
Stadium Sultan Ibrahim mendapat pengiktirafan global 'Stadium Of The Year 2020', menewaskan 19 stadium lain dalam undian awam yang dikendalikan StadiumDB.com berpangkalan di Poland.
![Tiga saintis wanita tempatan dianugerahkan L'Oreal - UNESCO FWIS Tiga saintis wanita tempatan dianugerahkan L'Oreal - UNESCO FWIS](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/http://img.astroawani.com/2019-10/51571316822_loreal.jpg)
Tiga saintis wanita tempatan dianugerahkan L'Oreal - UNESCO FWIS
Tiga saintis wanita tempatan diberi penghormatan anugerah L'Oreal- UNESCO sebagai pengiktirafan dalam usaha mereka menghasilkan kajian yang inovatif.
![10,000 unit lampu jalan LED bakal terangi kampung di Semenanjung 10,000 unit lampu jalan LED bakal terangi kampung di Semenanjung](https://resizer-awani.eco.astro.com.my/tr:w-177,h-100,q-100,f-auto/http://img.astroawani.com/2019-08/51566224401_Lynas.jpg)
10,000 unit lampu jalan LED bakal terangi kampung di Semenanjung
Sebanyak 10,000 unit Lampu Jalan Kampung (LJK) jenis light emitting diode (LED) akan dipasang di kampung seluruh Semenanjung menjelang tahun 2020.
Pengeluar pemancar cahaya LED sasar pasaran Asia
Myled Opto Technology Sdn Bhd sasar untuk mengembangkan jualan di pasaran tempatatan kepada 70 peratus berbanding 40 peratus.