The bluespine unicornfish (Naso unicornis), also known as the short-nose unicornfish, is a species of marine ray-finned fish belonging to the family Acanthuridae, the surgeonfishes, unicornfishes and tangs. This species is found in the Indo-Pacific.[3] It is occasionally found in the aquarium trade. It grows to a size of 70 cm in length. It is called kala ('thorn') in Hawaii,[3] dawa in New Caledonia, and ta or tā in Fiji.[4] However the name kala refers to all three species of horned unicornfish found around Hawaii.[5]
Taxonomy
The bluespine unicornfish was first formally described as Chaetodon unicornis by the Swedish-speaking Finnish explorer, orientalist, naturalist, and an apostle of Carl Linnaeus Peter Forsskål with its type locality given as Jeddah.[2] In 1801 the French zoologist Bernard Germain de Lacépède described a new species Naso fronticornis as a replacement name for Chaetodon unicornis, which, in 1917 David Starr Jordan designated as the type species of the genus Naso, which had first been proposed as a genus by Lacépède when he described N. fronticornis.[6] Naso is the only genus in the monogeneric subfamily Nasinae, proposed by Henry Weed Fowler and Barton Appler Bean in 1929[7] within the family Acanthuridae.[8]
Description
The bluespine unicornfish has a blueish-gray body with two blue spines on each side at the base of the tail and a short rostrum or bony horn on the forehead.[3][9] In small fish the horn is missing and males additionally have tail streamers.[3] These fish have a leather-like skin instead of scales. The bluespine unicornfish can grow up to 70 cm (28 in) with the largest one caught to be 5.8 kg (13 lb).[3][10][11]
Distribution
The bluespine unicornfish is very common in the tropical Indo-Pacific region, usually occurring at temperatures between 25 and 29 °C (77 and 84 °F).[11]
Habitat
The bluespine unicornfish are a near-shore fish. The juvenile tend to stay close to shore while the adults tend to live from shallow to the beginnings of the deep water staying within the upper 40 feet.[11] They tend to enjoy spots with waves or strong surges.[12] The bluespine unicornfish live often solitary on coral reefs or can be found in small schools of unicorn fish or as a part of larger schools with many other fish species.[3][11][13]
Diet
Bluespine unicornfish are herbivores and feed on brown and red algae with coarse or leafy blades.[11][12] Because it is one of a small number of species that consumes fleshy macroalgae (seaweed), it is of great importance to coral reef ecosystems.[14]
Invasive algae
Bluespine unicornfish have been recorded eating invasive algae species, such as .[13] This alga has become well established in reefs throughout the Hawaiian island of Oahu and is of concern because of its tendency to form dense, overgrown mats on and around corals that prevent nutrient acquisition. G. salicornia reproduces through fragmentation. The bluespine unicornfish feeds on G. salicornia which both helps reduce the size of the alga on reefs but also contributes to its spread as the fragments found in the fishes' feces are viable and can grow into new algal mats.[13]
Human use
Bluespine unicornfish are eaten in abundance due to how common they are. They are caught using nets, hook and line techniques, and by nighttime spearfishing.[14] They have a strong flavor and odor due to their diet. When skinned, the meat is white with a slight pink-red taint and a firm or moist texture. Bluespine unicornfish are usually eaten raw, boiled, grilled, baked or sauteed.[15]
The kala, the Hawaiian name for Naso unicornis and two other Naso species, was an important food source in pre-colonial Hawaii.[15] The tough skin of kala was sometimes stretched over a half coconut shell to make a small knee drum.[3] The Hawaiians also used kala in ceremonies between members of a tribe or between tribes.[15] Today kala is still a common food source to the people of Hawaii and other Pacific Islands.
Conservation
A commercial kala fishing permit is required by the Hawaiian Department of Land and Natural Resources; the daily take of kala is limited to four fish per person per day.[5] As of March 2024annual catch limit for the commercial kala fishery is 15,000 pounds, with the count beginning on August 1 of each year.[5]
Cultural significance
The bluespine unicornfish is frequently found on postage stamps, as company logos, school mascots, and as a motif in indigenous artwork.[14]
References
- ^ Abesamis, R.; Clements, K.D.; Choat, J.H.; et al. (2012). "Naso unicornis". IUCN Red List of Threatened Species. 2012: e.T177970A1506556. doi:10.2305/IUCN.UK.2012.RLTS.T177970A1506556.en.
- ^ a b Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Naso". Catalog of Fishes. California Academy of Sciences. Retrieved 25 July 2023.
- ^ a b c d e f g Hoover, John P. (2008). The ultimate guide to Hawaiian reef fishes sea turtles, dolphins, whales, and seals. John P. Hoover. Honolulu: Mutual Pub. ISBN 978-1-56647-887-8. OCLC 243960518.
- ^ Blust, Robert; Trussel, Stephen (2010). "*taRaq₂ unicorn fish: Acanthurus unicornis". Austronesian Comparative Dictionary. Max Planck Institute for Evolutionary Anthropology. Retrieved 8 November 2022.
- ^ a b c "New rules for uhu, manini, kole, kala, and Kona crab now in effect". dlnr.hawaii.gov. Retrieved 2024-11-11.
- ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Acanthuridae". Catalog of Fishes. California Academy of Sciences. Retrieved 29 July 2023.
- ^ Richard van der Laan; William N. Eschmeyer & Ronald Fricke (2014). "Family-group names of recent fishes". Zootaxa. 3882 (2): 1–230. doi:10.11646/zootaxa.3882.1.1. PMID 25543675.
- ^ J. S. Nelson; T. C. Grande; M. V. H. Wilson (2016). Fishes of the World (5th ed.). Wiley. pp. 497–502. ISBN 978-1-118-34233-6. Archived from the original on 2019-04-08. Retrieved 2023-07-29.
- ^ Bray, D.J. (2019). "Naso unicornis in Fishes of Australia". Archived from the original on 2017-05-01.
- ^ Animal-World. "Bluespine Unicornfish". Animal World. Retrieved 2021-12-15.
- ^ a b c d e "Bluespine Unicornfish". Georgia Aquarium. Retrieved 2021-12-15.
- ^ a b "Unicornfish". thisfish.info. Retrieved 2021-12-15.
- ^ a b c Bierwagen, Stacy L.; Price, Donald K.; Pack, Adam A.; Meyer, Carl G. (January 2017). "Bluespine unicornfish (Naso unicornis) are both natural control agents and mobile vectors for invasive algae in a Hawaiian Marine Reserve". Marine Biology. 164 (1): 25. Bibcode:2017MarBi.164...25B. doi:10.1007/s00227-016-3049-x. ISSN 0025-3162.
- ^ a b c Taylor, Brett M. (2019-07-03). "Standing Out in a Big Crowd: High Cultural and Economic Value of Naso unicornis in the Insular Pacific". Fishes. 4 (3): 40. doi:10.3390/fishes4030040. ISSN 2410-3888.
- ^ a b c Titcomb, Margaret (1972-11-01). Native Use of Fish in Hawaii. University of Hawaii Press. ISBN 978-0-8248-0592-0.
- Froese, Rainer; Pauly, Daniel (eds.). "Naso unicornis". FishBase. December 2008 version.
External links
- Photos of Bluespine unicornfish on Sealife Collection
