Hello everyone!
Before you continue to read on, I would like that you look out your window and look up at the sky. Do you see any stars?
This is the view of the sky outside my window at around 1 am and same as you, I am not able to see any stars. All I see is buildings still brightly lighted. If you look hard enough, you can even see the Singapore Flyer brightly lit in my photo! I bet you have guessed it yes I will be talking about Light Pollution in this post!
The light bulb is probably one of the greatest inventions of mankind allowing us to work efficiently even after dusk. However, ironically these light bulbs have a dark side. They have stolen the night away. The excess light that we use without thinking is endangering ecosystems more than you realize. Flora and fauna depend on Earth’s daily cycle of light and dark rhythm to perform critical behaviors such as reproduction, nourishment, sleep, and protection from predators (IDA, 2016). When mankind disrupts this cycle by lighting up the sky, there are negative and even deadly effects.
#1 Increase deaths
Birds can be disoriented and entrapped by artificial lights at night making them vulnerable to collision against obstructions (Odgen, 1996). Artificial lighting has attracted birds to various structures like smokestacks, lighthouses, broadcast towers, boats, greenhouses, oil platforms, and others at night, resulting in direct anthropogenic mortality, and interfere with migration routes. Many groups of insects, like moths, are attracted to lights. Artificial lightings like lamps may incinerate or desiccate moths (Frank, 1991).
#2 Reproductive behavior altered
Under increased lighting, frogs stopped mating activity at night and only resumed when shielded from the light (Longcore & Rich, 2004). In birds, some evidence suggests that artificial night lighting affects the choice of nest site. Birds would choose sites further away from lighting as far as possible (. Artificial lightings have altered available areas for reproduction making it harder for wildlife to reproduce.
#3 Communication
Visual communication within or between species that requires the dark might be impaired by artificial light. Some species like fireflies use light to communicate but are being affected by stray light (Lloyd, 1994). In addition, female glow worms which use bioluminescent flashes to attract male are now less visible (Longcore & Rich, 2004) further affecting reproduction as well.
#4 Predator-prey relationship
Increased illumination may be beneficial for diurnal species as they can continue to forage under artificial lights (Longcore & Rich, 2004) but not for their prey as they lack areas to stay hidden from predators. This causes an imbalance in a predator-prey relationship thus affecting ecosystem characteristics.
#5 Disorientate organisms
Constant artificial night lighting may also disorient organisms that are accustomed to navigating in a dark environment. An example is sea turtle hatchlings being disorientated by artificial light on the beaches such that they are unable to locate the sea (Salmon et al, 1995). The rapid increase in night lighting can also cause blindness in nocturnal animals
So what if you can’t see the Milky Way? Think again! Light pollution is worse than you imagine and have far-reaching effects on yourselves you might not even be aware of yet! I would like to share this video made by Seeker that provides a quick summary of light pollution.
That brings me to the end of this post on light pollution. Next up, I will be digging into the effects light pollution can have on plants. You might be wondering how is that possible? Well, stay tuned to find out!
See you guys soon!
References
, , and . 2000. Road illumination and nature. III. Local influence of road lights on a black-tailed godwit (Limosa l. limosa) population. Wageningen, The Netherlands: Alterra.
Frank, K. D. (1991). Impact of Outdoor Lighting on Moths. International Astronomical Union Colloquium, 112, 51-51. doi:10.1017/s0252921100003687
IDA. (2016, September 12). Light Pollution Effects on Wildlife and Ecosystems. Retrieved August 30, 2020, from https://www.darksky.org/light-pollution/wildlife/
. 1994. Where are the lightningbugs?. Fireflyer Companion 1: 1 2 5 10.
Longcore, T., & Rich, C. (2004). Ecological light pollution. Frontiers in Ecology and the Environment, 2(4), 191-198. doi:10.1890/1540-9295(2004)002[0191:elp]2.0.co;2
. 1996. Collision course: the hazards of lighted structures and windows to migrating birds. Toronto, Canada: World Wildlife Fund Canada and Fatal Light Awareness Program.
, , and . 1995. Behavior of loggerhead sea turtles on an urban beach. II. Hatchling orientation. J Herpetol 29: 568– 76.
