Pouched lamprey (Geotria australis) fish species and information / pictures of Pouched lamprey - Geotria australis

Pouched lamprey (Geotria australis) fish species information

Scientific Name
Geotria australis

Common Name
Pouched lamprey

Biology
Occurs in mud burrows in upper reaches of coastal streams for the first four years of life until metamorphosis and subsequent downstream migration to the sea. Adults inhabit the sea for an undetermined period and are parasitic on other fishes. Migrate upstream which may last for 16 months and spawn in freshwater. Adults are often found below weirs and dams during their spawning migration which may take them 60 km or more upstream of the coast. Migration mostly takes place in rainy nights when water levels are rising, with temperatures between 12-14.5°C and when there is extensive cloud cover or during the dark phase of the moon. Sometimes they exit the water by wriggling up the bank to bypass obstacles to migration. Adults stop feeding while in freshwater and die shortly after spawning. Maximum length reported to reach 62 cm TL. Common length is 45-50 cm. Status of abundance decreased due to proliferati

Classification

Classified By
Gray, 1851
Class
Lampreys (Cephalaspidomorphi)
Order
Lampreys (Petromyzontiformes)
Family
Lampreys (Petromyzontidae)

Distribution

Region
Atlantic, Indian and Pacific
Distribution
Atlantic, Indian and Pacific: coasts of all southern continents, extending into rivers of southern Chile and Argentina.
Range
34°S - 55°S

Environment

Climate
Temperate
Water Temperature From
Unknown °C
Water Temperature To
Unknown °C
Depth From - meters
Unknown m
Depth To - meters
Unknown m
Zone
demersal
Environment
Marine; freshwater; brackish; demersal; anadromous
Trophic Level
4.5 s.e. 0.80 Based on food items.
Occurs in Marine / Salt water
True
Occurs in Brackish water
True
Occurs in Fresh Water
True
Occurs on Reefs
False
Is kept in Aquariums
False

Physical Size and Genetics

Maximum Length
62.0 cm
Common Length
Unknown cm
Phylogenetic Diversity Index
PD50 = 1.0000 many relatives (e.g. carps) 0.5 - 2.0 few relatives (e.g. lungfishes)

Human Uses and Population

Human Uses
Fisheries: of no interest
Vulnerability
High to very high vulnerability (69 of 100)
Resilience
Very Low, minimum population doubling time more than 14 years (Preliminary K or Fecundity.)
Threat To Humans
Harmless
IUCN Red List Status
Not Evaluated