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Plecoglossus altivelis (Temminck & Schlegel, 1846)

Ayu sweetfish
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Plecoglossus altivelis   AquaMaps   Data sources: GBIF OBIS
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Image of Plecoglossus altivelis (Ayu sweetfish)
Plecoglossus altivelis
Picture by Islam, Md. S.

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Teleostei (teleosts) > Osmeriformes (Freshwater smelts) > Plecoglossidae (Ayu fish)
Etymology: Plecoglossus: Greek, pleko, plekein = to fold + Greek, glossa = tongue (Ref. 45335).
More on authors: Temminck & Schlegel.

Issue
All subspecies of Plecoglossus altivelis (Temminck & Schlegel, 1846) are synonymised under the species in Eschmeyer (CofF ver. Jul. 2010: Ref. 84883). Please send references, or more studies are needed.

Environment: milieu / climate zone / depth range / distribution range Ecology

Marine; freshwater; brackish; demersal; amphidromous (Ref. 51243); depth range 10 - ? m. Subtropical; 44°N - 23°N

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

Northwest Pacific: western Hokkaido in Japan southward to the Korean Peninsula, Taiwan and China.

Length at first maturity / Size / Weight / Age

Maturity: Lm 27.5, range 30 - 40 cm
Max length : 70.0 cm TL male/unsexed; (Ref. 12218); common length : 15.0 cm SL male/unsexed; (Ref. 35840); max. reported age: 3.00 years (Ref. 12218)

Short description Identification keys | Morphology | Morphometrics

Dorsal spines (total): 0; Dorsal soft rays (total): 10 - 11; Anal soft rays: 14 - 15; Vertebrae: 60 - 63. Pyloric caeca 350-400.

Biology     Glossary (e.g. epibenthic)

Typical amphidromous fish; appears in near shore from late autumn to spring (Ref. 11230). Found in lakes and rivers, preferring clean river water and can be found the entire river long, from the head to the mouth (Ref. 12218). Ascends the river during March when the temperature is around 10°C (Ref. 12218). Adults spawn in the spring, in the lower reaches of rivers. After spawning, some adults die while others return to the sea. Larvae enter the sea immediately after hatching and remain there during winter, feeding on plankton. In springtime, the young (5-7 cm TL) move upstream to the middle reaches of rivers to feed on algae. Fish (about 6-9 cm) start schooling at the river mouth and are insectivores and eat algae off small pebbles (Ref. 12218); this is assisted by small leaf-like teeth which are loosely attached to the jaw with two ligaments (Ref. 45181). Those that are ready to spawn (about 20 cm TL) move downstream to the lower reaches of the river. Spawning adults from the sea migrate upstream to the lower reaches as well. Some fish spawn two or three years in succession, others only once (Ref. 9987 & 559). River forms live usually only one year whereas lake forms can live two or three years (Ref. 12218). Reaches maturity at 30-40 cm (Ref. 12218). Highly esteemed food fish. Marketed fresh and consumed fresh, fried and broiled (Ref. 9987).

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

During spawning some fish go up the river and some fish spawn on the river shoreline above pebbles. Spawns at night and excavates a 10cm (diameter or depth?) pit. Eggs are around 1 mm in size and adhere to the sand or pebbles for 14 to 20 days before hatching. This fish is semelparous and releases eggs many times over a short period each time releasing ~10,000 eggs. Sometimes females that want to spawn but cannot, save their strength, and go to a deep stagnant pool. These females wait until spring before going up the river with young fish. After hatching, the larvae are 6 mm and flow with the water current eating plankton. Juvenile fish will come again to the river in spring. These live in schools. When schools of Plecoglossus altivelis return to their river they guard their territory and eat food (Ref. 12218). Reproductive mode varies between semelparity and iteroparity. Large females spawn once, while smaller females spawn twice during a two-week interval (Ref. 76896).

Main reference Upload your references | References | Coordinator | Collaborators

Masuda, H., K. Amaoka, C. Araga, T. Uyeno and T. Yoshino, 1984. The fishes of the Japanese Archipelago. Vol. 1. Tokai University Press, Tokyo, Japan. 437 p. (text). (Ref. 559)

IUCN Red List Status (Ref. 130435: Version 2024-2)

  Data deficient (DD) ; Date assessed: 03 September 2010

CITES

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Harmless





Human uses

Fisheries: highly commercial; aquaculture: commercial; gamefish: yes
FAO - Aquaculture systems: production; Fisheries: landings, species profile; Publication: search | FishSource | Sea Around Us

More information

Trophic ecology
Food items
Diet composition
Food consumption
Food rations
Predators
Ecology
Ecology
Population dynamics
Growth parameters
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversion
Recruitment
Abundance
Life cycle
Reproduction
Maturity
Maturity/Gills rel.
Fecundity
Spawning
Spawning aggregations
Eggs
Egg development
Larvae
Larval dynamics
Anatomy
Gill area
Brain
Otolith
Physiology
Body composition
Nutrients
Oxygen consumption
Swimming type
Swimming speed
Visual pigments
Fish sound
Diseases & Parasites
Toxicity (LC50s)
Genetics
Genetics
Heterozygosity
Heritability
Human related
Aquaculture systems
Aquaculture profiles
Strains
Ciguatera cases
Stamps, coins, misc.
Outreach
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References
References

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Internet sources

AFORO (otoliths) | Alien/Invasive Species database | Aquatic Commons | BHL | Cloffa | BOLDSystems | Websites from users | Check FishWatcher | CISTI | Catalog of Fishes: genus, species | DiscoverLife | ECOTOX | FAO - Aquaculture systems: production; Fisheries: landings, species profile; Publication: search | Faunafri | Fishipedia | Fishtrace | GenBank: genome, nucleotide | GloBI | Google Books | Google Scholar | Google | IGFA World Record | MitoFish | National databases | Otolith Atlas of Taiwan Fishes | PubMed | Reef Life Survey | Socotra Atlas | Tree of Life | Wikipedia: Go, Search | World Records Freshwater Fishing | Zoological Record

Estimates based on models

Preferred temperature (Ref. 123201): 13 - 22.6, mean 19.7 °C (based on 42 cells).
Phylogenetic diversity index (Ref. 82804):  PD50 = 1.5000   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00427 (0.00166 - 0.01096), b=3.06 (2.83 - 3.29), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245).
Trophic level (Ref. 69278):  2.8   ±0.16 se; based on food items.
Resilience (Ref. 120179):  High, minimum population doubling time less than 15 months (tm=1; tmax=3; Fec=50,000-100,000).
Fishing Vulnerability (Ref. 59153):  Moderate to high vulnerability (48 of 100).
Price category (Ref. 80766):   Unknown.
Nutrients (Ref. 124155):  Calcium = 78 [36, 203] mg/100g; Iron = 1.19 [0.62, 2.98] mg/100g; Protein = 16.2 [13.8, 18.2] %; Omega3 = 0.445 [0.196, 1.234] g/100g; Selenium = 73.2 [35.2, 156.1] μg/100g; VitaminA = 4.44 [1.39, 14.45] μg/100g; Zinc = 0.804 [0.513, 1.253] mg/100g (wet weight);