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🌊 Marine 🌡️ Subtropical

Japanese tenspined silver-biddy

Gerres akazakii Iwatsuki, Kimura & Yoshino, 2007
Max Length
16.9 cm
Max Weight
-
Lifespan
-
Trophic Level
3.3
Depth
2–3 m
Climate
Subtropical
Resilience
High
Vulnerability
22.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Known to inhabit the vicinity of river mouth basins, which may be considered strongly related to a minimum winter sea temperature of 16°C (less than 100 m depth). Specimens were collected in inlet basins, river mouth basins, or on shallow sandy bottoms strongly affected by freshwater from nearby river mouths. However, this species rarely occurs in the shallow coastal area with almost no freshwater effect. One specimen (MUFS 9584, 135 mm SL, 3 July 1993), had a clearly matured or water-hardened (transparent) egg, giving an indication of the spawning season of the species .

Scientific Name
Gerres akazakii
Authority
Iwatsuki, Kimura & Yoshino, 2007
Habitat
Marine
Climate
Subtropical
Max Length
16.9 cm
Depth Range
2–3 m
Trophic Level
3.3
Resilience
High
Vulnerability
22.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 10; Dorsal soft rays (total): 9; Anal spines: 3; Anal soft rays: 7.

🌀 Behaviour

Behavioural data for Japanese tenspined silver-biddy is currently being reviewed.

🦐 Diet

Diet information for Japanese tenspined silver-biddy is currently being compiled.

🥚 Reproduction

Reproduction data for Japanese tenspined silver-biddy is currently being compiled.

🌍 Habitat & Distribution

Marine; brackish; demersal; depth range 2 - 3 m . Subtropical Northwest Pacific: likely to be endemic in Japan.

🌿 Ecology

Zone Preferences
🌊 Marine 🌿 Brackish ⬇️ Benthic
Trophic Level
3.3±0.3

📐 Morphometrics

Length–Weight Relationship: W = 0.01413 × L3.04 (TL)
Max TL
16.9cm
Dorsal Spines
10
Dorsal Rays
9
Anal Spines
3
Anal Rays
7

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
22.00/100
Low vulnerability
Trophic Level
3.3
Predator
Climate Zone
Subtropical
Described By
Iwatsuki, Kimura & Yoshino, 2007

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