DiscoverSpeciesSharks and rays
Bull head
Heterodontus japonicus
- Water temperature20–20 °C
- Best monthsApril, May, and September
- How commonRare
Photo credit: (c) OpenCage Systems, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
About this species
The Japanese bullhead shark is a species of bullhead shark in the family Heterodontidae found in the northwestern Pacific Ocean off the coasts of Japan, Korea, and China. This benthic shark occurs at depths of 6–37 m (20–121 ft) over rocky bottoms or kelp beds. Measuring up to 1.2 m (3.9 ft) long, it can be identified by its short, blunt head, two high dorsal fins with anterior spines, and pattern of irregularly shaped, vertical brown bands and stripes. The Japanese bullhead shark is a docile, slow-swimming species that feeds mainly on shelled invertebrates and small bony fishes. Reproduction is oviparous, with females laying spiral-flanged eggs in communal "nests". This species is of little interest to fisheries.
Text from the Wikipedia article “Japanese bullhead shark”, licensed CC BY-SA 4.0. Read the article
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 0 records
- February: 1 records
- March: 0 records
- April: 3 records
- May: 4 records
- June: 2 records
- July: 0 records
- August: 1 records
- September: 4 records
- October: 2 records
- November: 1 records
- December: 1 records
Depth and water temperature
Water temperature
Recorded in surface water of 20–20 °C
Photos
(c) Jennifer Feuchter, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Nicola Crockford, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Nicola Crockford, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Bull head, Cat shark, Cestracion shark, Japanese bullhead shark, Japanese horn shark, bull head, cat shark, Japanease bullhead shark
Names in 4 more languages
- Spanish
- dormilón japonés
- French
- requin dormeur nekozame
- Japanese
- nekozame, Nekozame, sazaewari, sazaiwari, ネコザメ
- Simplified Chinese
- 寬紋虎鯊, 日本異齒鯊, 虎沙, 角鯊
Other scientific names: Cestracion japonicus
Similar species
BullheadHeterodontus portusjacksoni
Crested bullhead sharkHeterodontus galeatus
Mozambique bullhead sharkHeterodontus ramalheira
Barred bull-head sharkHeterodontus zebra
Sources and credits
Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).
- Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
- Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
- Conservation status as published by GBIF (IUCN Red List).
- Species data updated November 3, 2026.
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