Tag Archives: fish

It’s a Fish – Day One

Seasearch is a project involving volunteer sports divers to record the habitats and marine life around the coast of the UK. I recently attended one of their training courses (Fish ID) in Newquay Cornwall. The course was organised by the Seasearch Organiser for Cornwall, Cat Wilding, who’s also the marine survey officer for Cornwall Wildlife Trust, and the tutor was Dr Frances Dipper.

The course was being held at Newquay College and after the usual introductions, the day started with a short presentation where Frances talked about some of the main groups and families and the general characteristics of fish that would be used to identify them. In the second presentation, we moved on the fundamentals – the FLEMMS system. The FLEMMS system is designed so that you can gather a lot of information for identification in what may be a relatively short glimpse as the fish disappears into a clump of weed. FLEMMS stands for:

  • Fins, specifically the unpaired fins. How many dorsal? How many ventral? Is the tail concave, convex or straight?
  • Lateral line. Is it visible in that particular species? If so, is it straight or curved?
  • Eyes. Where are they positioned? Are they large or small? Are they bulging?
  • Mouth. Where is it positioned? Is one of the lips prominent or are the lips equal? Are there any barbels?
  • Markings. Are there any distinctive patterns, colours or spots?
  • Size. Relate the size to something more general: is it finger, hand or arm size?

We then got to practise and started with the easy option – identifying fish from photographs, although as we progressed Frances would mimic the fish disappearing by changing the slides faster. We could either make quick notes about features or make a quick diagram. I chose the diagram method. It starts with a cross to represent the fish onto which we mark the fins, lateral line, eyes, mouth details, etc. The symbols aren’t standardised since it’s an aide to our memory for identification after returning to shore, rather than a reference for others, so we might use lines or shapes for fins.

FLEMMS diagram of a haddock (Melanogrammus aeglefinus)
FLEMMS diagram of a haddock (Melanogrammus aeglefinus)

This fish has three dorsal (the first prominent) and two ventral fins which, in UK waters, shows that it is a member of the cod family. There is a curved lateral line, the upper jaw extends below the lower jaw, which has a small barbel. There is a black marking just below the lateral line. The combination of the first dorsal fin and the black ‘thumbprint’ shows that this is a Haddock (Melanogrammus aeglefinus).

FLEMMS diagram of a Shanny (Lipophyrys pholis)
FLEMMS diagram of a Shanny (Lipophyrys pholis)

This is a fish with a long single dorsal fin and a single ventral fin. The tail is convex. The head is complex, with prominent bulging eyes, and thick lips with the upper lips horizontal and slightly protruding over the lower lips. The fish is around hand size with blotchy markings. The single dorsal fin and the lack of head tentacles identifies this as a Shanny (Lipophyrys pholis).

After lunch, we went to the Blue Reef Aquarium to practise on more mobile and less cooperative fish, which included blennies, gobies, wrasse, and skates and rays.

Tompot Blenny (Parablennius gattorugine)
Tompot Blenny (Parablennius gattorugine)
CC BY-SA Duncan Greenhill

We returned to the lab at Cornwall College and had another brief presentation on some of the difficulties and confusions we might face trying to identify fish such as fish keeping fins folded down (which causes us to miscount), and changes in colouration and pattern as the fish matures or changes sex. There was a perfect end to the day with a course meal looking out over the clifftop across Great Western Beach as the surf rolled in and we wondered about conditions for the following morning.

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