📸 PhotoPhoto: Izuzuki · CC BY 2.5 · Wikimedia Commons Source
Japanese jack mackerel
Trachurus japonicus (Japanese jack mackerel · マアジ)
💡 Everyday Comparisons for Size, Mass & Speed
- 💡 Its maximum weight of 660 g is slightly heavier than a 500 mL bottle of water (Comparison).
- 💡 It can be seen along the southern coast of Korea and Jeju Island (National List of Species of Korea).
- 💡 It is a target species for commercial fisheries and aquaculture (FishBase).
Reference standards: coach bus ~12 m, mid-size car ~4.9 m, compact car ~1 t, basketball hoop 3.05 m, credit card 8.56 cm.
Site-computed relative index from recorded values; not a formal scientific metric.
📖 1. Overview
The Japanese jack mackerel is a schooling coastal marine fish that can be seen along the southern coast of Korea and Jeju Island. Juveniles shelter among drifting seaweed.
🦴 2. Anatomy & Morphology
Its head and body are slightly flattened from side to side, with a dark blue back and a silvery-white belly. There is a small black spot at the tip of the gill cover, the lateral line is complete, and the scales are round.
🔍 3. Ecology & Behavior
It mainly feeds on zooplankton such as crustaceans as well as bottom-dwelling invertebrates. Its spawning season is from April to July.
🇰🇷 4. Connection to Korea
According to the National List of Species of Korea, it lives along the southern coast and Jeju Island.
📚 Sources & References
- • IUCN Red List NT (2018) — https://www.iucnredlist.org/species/20437783/67871570
- • IUCN Red List category NT — latest assessment at iucnredlist.org
- • catalogueoflife.org — 57PKM
- • iucnredlist.org — 67871570
- • 국가생물종목록(국립생물자원관) ktsn 120000058497 — https://species.nibr.go.kr/home/mainHome.do?cont_link=009&subMenu=009002&contCd=009002&ktsn=120000058497
- • wikidata.org — Q1330320
- • commons.wikimedia.org — File:MaAji.jpg
- • fishbase.se — Trachurus-japonicus.html
- • species.nibr.go.kr — mainHome.do
- • Silhouette: PhyloPic — Richard J. Harris · Public Domain Mark 1.0 (Related taxon silhouette — Scomberoides lysan)
Recorded dimensions are widely cited representative estimates from public literature and may vary by study or specimen.