Rainbow Parrotfish - Gabbie Nelson

 Rainbow Parrotfish

Background

    The rainbow parrotfish, also known as Scarus guacamaia, is a fish living in tropical regions from the Bahamas to Argentina.  They can live up to seven years old and grow as much as four feet. They dwell at anywhere from 3 to 25 meters in the water column. 

Diet

Parrotfish are herbivores and mainly feed on algae. In fact, they will spend 90% of their day consuming algae growing on coral reefs. This provides an important ecosystem service for the coral as it prevents the algae from outgrowing the reef, and the coral zooxanthellae are able to photosynthesize. The parrotfish has two plates, which are teeth fused together, that it uses to chew food. It will then defecate, excreting bits of digested coral that in turn provide biogenous sediment for the ocean floor. 

Reproduction

One dominant male mates with all the females. A dominant male can arise through being born a male, also called a primary male, or be born a male and transition to male, a secondary male. Once the dominant male dies, a primary or secondary male will replace him. Primary males may also disguise themselves as females in an effort to sneakily mate with females without drawing the attention of the dominant male. 

Impact on humans 

Rainbow parrotfish aren't a direct threat to humans, but can cause harm if consumed. They have a high concentration of ciguatoxin in their tissue, caused by a high consumption level of dinoflagellates. Symptoms range from dizziness to nausea and vomiting. This can become serious if untreated, but early treatment includes pumping the stomach. 

ESA status and conservation

Fortunately, there are no serious threats facing the rainbow parrotfish. IUCN has them listed as near threatened. They can become vulnerable to local extinction from overfishing or invasive species. A future threat to look out for is climate change. 

References 

https://www.fishbase.se/summary/1155#

https://rarediseases.org/rare-diseases/ciguatera-fish-poisoning/

http://species-identification.org/species.php?species_group=caribbean_diving_guide&id=247

https://www.nature.org/en-us/get-involved/how-to-help/animals-we-protect/parrotfish/

https://sta.uwi.edu/fst/lifesciences/sites/default/files/lifesciences/documents/ogatt/Scarus_guacamaia%20-%20Rainbow%20Parrotfish.pdf

Gabbie Nelson