DavidHowdon's picture

Rock pool fish

Observed: 21st August 2012 By: DavidHowdon
Amateur Entomologists' SocietyLondon Natural History SocietySelborne Society
DavidHowdon’s reputation in Fish
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Description:

Perhaps around 50-60mm long. In a rock pool.

Identifications
Species interactions

No interactions present.

Comments

DavidHowdon's picture

Thanks for the ID nightfly

To help improve my skills can you exapnd a little bit on the features that led you to this conclusion?

A similar fish I found a few years ago I identified as a Blenny - no agreements with that one. http://www.ispot.org.uk/node/75348

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David Howdon

nightfly's picture

Yeah David I would say your

Yeah David I would say your other one is without doubt Common Blenny, its almost a carbon copy of this one. It looks a bit younger and smaller but identically marked young blenny.

If you would like to add the ID I would gladly agree it.

Cathal.

DavidHowdon's picture

Added

I suspect I don't spend enough time in coastal locations to ever be confident with these.

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David Howdon

nightfly's picture

I would recommend using a

I would recommend using a kids net to catch and closely inspect rockpool fish in the hand anytime you do go rockpooling. If the pools you are looking in are anything like the ones I visit, it becomes a matter of trying to find small fish which arent common blenny. You wont be long familiarising yourself with the vagaries of common blenny colouration if you keep catching them and observing them at rest in shallow water.

Cathal.

nightfly's picture

Hi David, Its simply the

Hi David,

Its simply the colouration, markings and shape. This one looks very typical for a common blenny of about 4/5cm. They tend to lose a lot of the whitest markings as they get bigger. Can become very dark and monochrome or can remain quite mottled, criptically coloured. I dont know if gender has a bearing on colouration.

They are by far the commonest rockpool fish I see and those images cant be confused with any other species I know or am personally familiar with. This probably isnt giving you the answer you would like, tbc.....

Cathal.

DavidHowdon's picture

Thanks

To be honest sometimes "because it just looks like one" is the best answer to this sort of question.

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David Howdon

nightfly's picture

2nd image is the important

2nd image is the important one. The birds eye view ones could be slightly indeterminate, if that makes sense.

The 2nd pic shows enough of the profile to see the long tapering shape, blunt face and very typical row of white marking on the flank. Having said that, they dont all possess such markings even as immature ones. I had blennies in my hand today which were 3cm long and virtually monochrome slate grey(discoverd beneath rocks). Environment probably has a bearing on colouration as with most rockpool fish.

I would suggest that the lightness of the fish might be related to whether it is out in the open, how sunny it is etc.

They often show a circular marking directly behind the eye on the gill plate, your fish is a good example.

Cathal.

nightfly's picture

David, I'd like to hear your

David,

I'd like to hear your thoughts on this moth please?

http://www.ispot.org.uk/node/274057

Cathal.