Home · Gerreidae · Blue-backed silver biddy
Blue-backed silver biddy (Gerres erythrourus) — Gerreidae

Blue-backed silver biddy

Gerres erythrourus
Family: Gerreidae
LC · Least Concern

The Blue-backed silver biddy (Gerres erythrourus) is a brackish-water fish of the family Gerreidae that grows up to 30 cm.

Length
30 cm
Water
Brackish
Depth
1.0–40.0 m
Diet
Carnivore
Behaviour
Small groups
Body shape
Flat / disc-shaped
Substrate
Stone or rock
Danger
Harmless
Edibility
Commonly eaten

Description

The deep-bodied mojarra is a mojarra (Gerreidae) from the Indo-Pacific. The species grows to about 30 cm and has a deep, silvery, laterally compressed body with sometimes reddish fins and a highly protrusible mouth that it can extend downward as a tube. It is a marine species that also enters estuaries and coastal lagoons. It forms schools over sandy bottoms. Small juveniles feed on zooplankton, while larger individuals sift small polychaetes, bivalves and crustaceans from the bottom. The species is harmless to humans.

Frequently asked questions

How do you recognise the Blue-backed silver biddy?

The Blue-backed silver biddy has a flattened, disc-shaped body, is mainly silver-grey and shows a plain pattern.

Where does the Blue-backed silver biddy live?

The Blue-backed silver biddy lives in brackish water and is mostly found around stony or rocky ground.

How big does the Blue-backed silver biddy get?

The Blue-backed silver biddy grows to a maximum of about 30 cm. On average the species is around 25 cm.

Is the Blue-backed silver biddy dangerous to humans?

No, the Blue-backed silver biddy is harmless to humans.

Is the Blue-backed silver biddy edible?

Yes, the Blue-backed silver biddy is commonly eaten.

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All data

Identification

Dutch name
Roodstaart-mojarra sourced
English name
Blue-backed silver biddy verified
Scientific name
Gerres erythrourus
Family
Gerreidae
Other names
Deep body mojarra; Deep body silver biddy; Deep-bodied mojarra verified

Appearance

Size class
Medium verified
Max length (cm)
30.0 verified
Average length (cm)
25.0 verified
Body shape
Flat / disc-shaped sourced
Dominant colour
Silver / grey inferred
Pattern
Plain inferred
Tail shape
Forked inferred
Mouth position
Inferior (downward) inferred
Lips
Thin inferred
Barbels
No sourced
Dorsal fins
One continuous inferred
Dorsal spines
Yes sourced

Habitat & distribution

Water type
Brackish sourced
Substrate
Stone or rock sourced
Min depth (m)
1.0 verified
Max depth (m)
40.0 verified
Origin
Native sourced

Behaviour & biology

Diet
Carnivore sourced
Social behaviour
Small groups inferred
Territorial
No inferred
Reproduction
Separate sexes sourced
Sexual dimorphism
No inferred

For anglers

Edibility
Commonly eaten sourced
Fishing method
Vissen met natuurlijk aas (vis, garnaal, worm) of kunstaas dicht bij rif- en rotsstructuren. inferred
Regulations source
FishBase ↗ inferred

Safety

Danger to humans
Harmless sourced

Status & sources

Sources
FishBase via GBIF (DwC-A), CC-BY-NC 4.0

Same genus Gerres

More from the family Gerreidae

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