Blennius ocellaris - Butterfly blenny - Llyfrothen adeiniog
Butterfly blennies have a huge dorsal fin and when it is erect they are
unmistakable! However, they may not have their dorsal up or may even be
sheltering under a stone or shell, or they (males) may even be guarding
their eggs which are often laid inside an empty whelk shell.
When
guarding eggs, a male will avoid leaving them if he possibly can and
often appears to lower and point his head appendages forward,
presumeably in a warning display - any information about this behaviour
would be welcomed.
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