Skip the menu

MOE home > Nature and Parks > EBSA home > Coastal Area > 13405 Osaka Bay


Coastal Area 13405 Osaka Bay

Basic Information A separate window opensReferences

Relevant municipalities Izumisano, Tajiri, Sennan-gun, Osaka Prefecture; Chuo Ward, Kobe, Hyogo Prefecture
Area (km2) 621

Reason(s) for selection A separate window opensCriteria

Selected due to high levels for the criteria 3, and selected by expert for reasons that overlapping of spawning grounds for multiple fish species. Note the following.
Note: These waters are considered important at depths of 10-30m because they serve as spawning grounds for several fish species. On the other hand, these waters’ environment had degraded by anthropogenic activity and anoxic polluted water mass reported. It should be noted that whether these waters should be as EBSA or not was a subject of debate in the expert committee. More data collection is desirable by the next review.

Characteristics A separate window opensReferences

These waters in Osaka Bay are 10-30 m in depth. In these waters the spawning grounds of multiple species overlap. The spawning grounds of Kareius bicoloratus are found in coastal zones up to 30 m deep in the southern and northwestern parts of the bay, those of marbled sole in the shallow waters at least 10 m deep and shore-zone seaweed beds of the northwestern part of the bay, the southeast to southern parts of the bay, and the southeast coast of Awaji Island, those of bastard halibut in the shallow waters 20-50 m deep and seaweed beds of the northwestern part of the bay, the southeast to southern parts of the bay, and the southeast coast of Awaji Island, and those of Japanese blue crab in the tidal mud flats and river mouth areas of the southeast to southern parts of the bay. Main spawning grounds of Japanese tiger prawn are in the offshore zone up to 10 m deep, those of Repomucenus richardsonii in the waters around 10 m deep, Japanese sea bass up to 30 m in depth, dotted gizzard shad in the northern area (Fisheries Agency, 1999; Osaka Prefecture, Research Institute of Environment, Agriculture and Fisheries).

Environment / Habitat infromation A separate window opensData source

Tidal mud flats (km2)
Moba (seaweed bed) (km2)
Coral reef coverage (km2)
Natural coast (km) 0
Rate of natural coast (%) 0
Sand bank / submerged sand bank
Other habitats

Species information (*) A separate window opensData source

Criteria 1
<Bivalva, Gastropoda>
Corbicula japonica
Criteria 2
Larus crassirostris (Black-tailed Gull)
Larus crassirostris (Black-tailed Gull)[Br/Ne]
Egretta sacra (Pacific Reef-egret)[Br/Ne]
Sterna albifrons (Little Tern)
Sterna albifrons (Little Tern)[Br/Ne]
Charadrius dubius (Little Ringed Plover)[Br/Ne]
Ammodytes personatus (Japanese sand lance)[Sp]
Scomberomorus niphonius (Japanese Spanish mackerel)[Sp]
Seriola quinqueradiata (Japanese amberjack)[Sp]
Trachurus japonicus (Japanese jack mackerel)[Sp]
Pleuronectes yokohamae (Marbled flounder)[Sp]
Pagrus major (Red seabream)[Sp]
Amphioctopus fangsiao (Ocellated octopus)
Octopus vulgaris (Common octopus)
Criteria 3
Sterna albifrons (Little Tern)
Cicindela lewisi
Criteria 7
<Bivalva, Gastropoda>
Corbicula japonica
<Vascular Plants>
Aster tripolium (Sea aster)

* This is the species list of which meet the criteria. In that matter, this list does not include all species that inhabit the individual area.
Abbreviation in the information is as follows.
[Br/Ne] : Adjacent water of breeding area or nesting site
[Sp] : spawning area
[Ad] : species not used for analysis but add to the list because inhabit information was collected later
[Ex] : species used for analysis but considered to be possibly extinct in the EBSA region (area)
No mark : data of species distribution


Back to the top of this page