Last week we discussed how baby sea turtles are susceptible to light pollution. This week we’ll like to introduce dinoflagellates! 😀
What are they?
Dinoflagellates are a type of plankton that bioluminescent in a bluish-green colour. When touched or when water nearby is disturbed, dinoflagellates light up. The bioluminescence produced by dinoflagellates helps them to defend against predators and illuminate predators when they are ingested (Judson, 2015). For instance:
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- Dinoflagellate gives off a sudden burst of light to startle predators and buy time to escape.
- The light emitted from dinoflagellate also helps fishes spot their preys. i.e. When the critters move causing disturbances, the water surrounding them lights up.
- Not to mention, critters are predators of dinoflagellates. When ingested, dinoflagellates light up the insides of those critters, and hence exposing dinoflagellates’ attacker (critters) to their predators as well.
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Dinoflagellates glowing inside a shrimp
Extinction Threats
Though we are not exactly sure how artificial light affects dinoflagellates, studies have discovered that insects that bioluminescent like the firefly population is on the decline due to light pollution.
The Italic Firefly (Luciola italica)
Artificial light at night can affect fireflies that are nocturnal negatively as they rely on bioluminescent courtship signals to locate mates and artificial light interferes with such signals (Reed, 2020). As a result, it can potentially cause a reduction in mating success. Moreover, observations showed that the presence of fireflies is reduced in areas with high levels of artificial light at night. This is evident by the absence of the Luciola italica population in the city of Turin, Italy (Reed, 2020).
Watch this video below for details on dinoflagellates 😀
References
Reed, J.M., Nguyen, A., Owens, A.C.S. & Lewis, S.M. (2020), “Linking the seven forms of rarity to extinction threats and risk factors: an assessment of North American fireflies”, Biodiversity and conservation, vol. 29, no. 1, pp. 57-75.
Judson, O. (2015), National Geographic. Luminous Life. Retrieved November 9, 2020 from https://www.nationalgeographic.com/magazine/2015/03/bioluminescent-organisms-scientific-research/