• Name: Giant goby | Gobius cobitis
  • Size: 27cm in length
  • Life span: 10 years 
  • Diet: Crustaceans, small fish, insects and large amounts of green algae
  • Reproduction: Giant goby usually mature in their second year when females can produce 2 clutches of eggs each season.  Eggs are attached to the under surface of large boulders, where they are fertilised and then guarded by the male 
  • When to see: Spring, Summer and Autumn (April to October)
  • Where to see: Sheltered rockpools and under boulders i.e. Porth Hellick, St Mary's | Covean, St Agnes | Great Bay, St Martin's in Scilly.  
  • Conservation status: Rare
  • Population Trend: Unknown
  • Threats:  Human activity (i.e. disturbance), pollution, climate change (changes in weather patterns, changing sea temperatures). 
  • Fun Fact: The Giant goby is protected under the Wildlife & Countryside Act 1981, making it a criminal offence to disturb individuals or damage their rockpool homes!

Description: The Giant goby is Britain's largest goby, reaching a huge 27cm in length, compared to its Rock goby (Gobius paganellus) cousin which can reach lengths of around 13cm.

The Giant goby has relatively small and well spaces eyes, a short tail stalk and a deep body throughout it's length; it is greyish to olive brown in colour with "salt and pepper" markings.  Breeding males are generally darker in colour that females.

In Great Britain in 1998 the species was added to Schedule 5 of the Wildlife and Countryside Act 1981. Under this Act it is an offence to kill, injure, take or sell giant gobies, or to damage or destroy any structure or place used by a giant goby for shelter or protection. Furthermore, it is included in English Nature's Species Recovery Programme.

The Giant goby inhabits high shore rock pools, often with a freshwater input and in Britain it's distribution is restricted to the south west coast of England (predominantly Cornwall and the Isles of Scilly).

Bonus fact!  Giant gobies can change colour depending on mood and surroundings.


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With thanks to Matt Slater for the Giant goby image