British Marine Life Study Society

The only known excellent photograph
is on the Norwegian web site of Frank Emil Moen.
Norwegian Marine ***

Eelpout (Photograph by Luke Richards, Isle of Wight)
Second photograph by Luke Richards (Isle of Wight)
from a specimen caught in pools on the Orkney Isles.

Common Name(s):
 Eelpout, Viviparous Blenny 
Scientific Name:
Zoarces viviparous
Usual Size:
 30 cm
UK Record Weights from rod/line:
13 oz   368g      Redcar Shore, Yorkshire 
                         H Hanison        1982
Boat:  N/K
Norway:  560g  Nevlunghavn, 17.01.88 

MAFF Minimum Size: Shore: Boat:

Elongate eel-like fish with a broad head and front half of the body (tapers towards the tail fin), and a large wide mouth. Eyes at the top of the head. Large pectoral (side) fins. Single dorsal fin runs almost the length of the fish. 
Brown with variable darker patterns. Sometimes very dark and others are yellowish. The pectoral fins are reported to be red in the male during the breeding season, but I have not seen this or any photographs. 
Mucus covered skin with a few small scales.
NB:  In at least one popular book the Butterfish, Pholis gunnellus, has been wrongly labelled as Zoarces viviparous and this has caused confusion amongst divers because the Butterfish is an abundant fish with a wider range but otherwise a very similar distribution as the Eelpout. 
Similar species:  Vahl's Eelpout  Lycodes vahlii,  Esmark's Eelpout  Lycodes esmarkii,  Sar's Eelpout Lyenchelys sarsiii.
These three species in the same family Zoarcidae are found to the north of the British Isles, but probably occur around the Shetland Isles.
Viviparous (rare amongst British marine fish). Mating occurs in the autumn (August-September) and the eggs hatch out about two months later. (They may hatch in 4 weeks - two different references, it may also depend on temperature. AH).
Bottom dweller. Muddy and rocky benthic from rocky shores, estuaries to about 40 metres. 
Small crustaceans (?). Exact diet not known at the time of writing.
North Sea,  Baltic, NE Atlantic (off Scandindavia). Rare at the eastern end of the English Channel. One Shorewatch Report from Dover. On the shore off the East Anglian coast, but frequency unclear because of misidentifications. 
Additional Notes:
All reports to the Shorewatch Biological Recording Scheme are very welcome.

Eelpout, Zoarces viviparus (also known as the mother of eels) has been classified by some workers as an estuarine 
resident, however from work carried out on the Humber Estuary, I've only recorded the species occasionally, which 
appears to 'buck the trend' as far as northern estuaries are concerned.  Within the Tyne and Blyth and Tees 
Estuaries the species appears to be recorded more frequently.  I have however, often recorded the species 
around Flamborough Head and on Filey Brigg (more so than in the Humber, and over a smaller sampling period).  We are 
also seeing increased numbers of Twaite and Allis Shad (large ones to almost 1 kg) and Red Mullet to over 0.6 kg.
 Nigel Proctor

The Environment Agency monitors fish populations in estuaries in NE England and Zoarces regularly turns up in trawls from the Tyne,Wear and Tees. - albeit in small numbers.  We believe that they only occur in significant numbers on the east coast from the Forth northwards.
John Orr 

I have collected a Eelpout from a rockpool near Largs, Scotland. December 2001. Report by Davy Holt.

Hello,  Message to the British Marine Wildlife Forum (commenced 1 August 2000)
Group Home:

Eelpout, Zoarces viviparus

I did a quick check at MERMAID for the Eelpout.

This was to show subscribers what a valuable Marine Environmental Resource this could be (in practice).

This is a record from the southern coast of the Bristol Channel (opposite Swansea for Jim Hall).
Actually, this record was picked because it seemed out of the normal range for this species. But this could indicate how scanty the existing records are. 

Mermaid includes records for the Yorkshire coast, but none from the Norfolk coast, where I have unconfirmed records on file somewhere (they can be found but it takes time because they are in Glaucus and not on the computer). 

Mapping and Information Database

The Eelpout is a particularly interesting species to map because it is on its southernmost part of its distribution range around Britain. Any records from the Netherlands and Belgium? How common is it off Norway?
for a photograph.

I assume MARLIN want records for this species, and I am interested in all reports from rockpoolers and divers, including females with live young.

The BMLSS file is at:

No supplementary records are appended.

Extract: only part of the entry in MERMAID

Site Record Survey no: 337 Site no: 1 

Rockham Bay 
Description: Sheltered from the South and SW by Morte Point. Exposed ridges and gullies on the West side. More rugged ridges, to several meters, affording shelter on the Eastern side of the bay. Shaley rock around a region of quartz on the E side some of this with standing water which drained at extreme low water. Dense Kelp at ESLW with rich associated community. Good variety of habitats with an excellent under boulder fauna.
Previously unsurveyed. Site Details: 

Position: SS 458 462 


Andy Horton
British Marine Life Study Society


This small fish is captured and eaten in the Baltic and the northern part of its range where it is common.
It is also eaten by Otters on the nothern Scottish coast. In the Shetland Isles Eelpout make up one third of the diet of Otters. 

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