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🌊 Marine 🌡️ Polar

Emerald rockcod

Trematomus bernacchii Boulenger, 1902
Max Length
28 cm
Max Weight
-
Lifespan
10 yrs
Trophic Level
3.4
Depth
0–700 m
Climate
Polar
Resilience
Medium
Vulnerability
53.00/100
Typical Length
25 cm
Depth Zone
demersal

📖 Overview

Found in seafloors, well adapted to extremely low and stable temperatures (-1.86°C), annual mean temperature of McMurdo Sound) . Feed on polychaetes, gastropods, isopods, amphipods and few algae. Spawn once a year . Utilized for human consumption. The report by Ref. 4537 as commercially important is probably a mistake for Trematomus eulepidotus (SAU, NB303).

Scientific Name
Trematomus bernacchii
Authority
Boulenger, 1902
Habitat
Marine
Climate
Polar
Body Shape
Fusiform / normal
Max Length
28 cm
Lifespan
10 years
Depth Range
0–700 m
Trophic Level
3.4
Resilience
Medium
Vulnerability
53.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 4 - 6; Dorsal soft rays (total): 34 - 39; Anal soft rays: 31 - 35. Body brownish, large dark spots in two or three series on body. Spinous dorsal blackish in upper part .: fusiform / normal.

🌀 Behaviour

Behavioural data for Emerald rockcod is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🛡️ Egg Guarder

Although members of this Family are known to tend to egg masses, it is assumed that because of the high fecundity, this species is a non-guarder (RF), to be corrected if direct information becomes available.

🌍 Habitat & Distribution

Marine; demersal; depth range 0 - 700 m , usually 0 - 200 m . Polar; 61°S - 78°S South Shetland, Elephant and South Orkney islands.

🌿 Ecology

Zone Preferences
🌊 Marine ⬇️ Benthic
Trophic Level
3.4±0.1
Food Items

polychaetes, gastropods, isopods, amphipods and few algae

📐 Morphometrics

Length–Weight Relationship: W = 0.00537 × L3.24 (TL)
Max TL
28cm
Dorsal Spines
5
Dorsal Rays
37
Anal Rays
33

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
53.00/100
Moderate-High vulnerability
Trophic Level
3.4
Predator
Body Shape
Fusiform / normal
Climate Zone
Polar
Described By
Boulenger, 1902

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 12 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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