a = Shallow, b = Middling, c = Deep
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1a) Common cuttlefish
1b) Its a courting male
1c) Sea grapes

2a) Scampi
2b) In burrows in soft mud in deep water
2c) Dublin Bay prawn, Norway lobster, langoustine

3a) Brittle stars
3b) Plankton and suspended particles
3c) 10,000

4a) A starfish
4b) The spiny starfish (Marthasterias glacialis)
4c) Removing free-loaders

5a) Plumose anemone
5b) Orange, green or brown
5c) Pieces break off to form new anemones, a type of asexual reproduction or budding

6a) A sea slug
6b) Both!
6c) Sea lemon (Archidoris pseudoargus)

7a) No!
7b) The bryozoans - also called sea mosses even though they are animals! This is hornwrack
7c) Lemon

8a) A sponge
8b) Filter feeds
8c) Bores into rock (a boring sponge!)

9a) You would get a powerful sting!
9b) A lesser weever
9c) Soak the affected body part in water as hot as you can take

10a) A dog-whelk
10b) Barnacles and mussels, by drilling into their shells
10c) Females grow male sexual organs and become sterile

11a) The wrasse (corkwing)
11b) Its a courting male
11c) Building a nest

12a) Coral
12b) Sea pen
12c) It can produce pulses of light

13a) Its re-growing from a single arm
13b) Common starfish (Asterias rubens)
13c) The inlet to its hydraulic system (madreporite)

14a) Thornback ray
14b) The (now inappropriately named) common skate
14c) They breathe in through holes on the top of their head (spiracles)

15a) No, theyre in a pre-mating embrace
15b) Just after she has moulted her armour
15c) Omnivore

16a) A worm (flatworm to be precise)
16b) Candy stripe flatworm
16c) Tape worms, liver flukes etc.

17a) Blenny
17b) Shanny, very shallow water or even out of the water
17c) Almost black (with white lips)

18a) Sea squirts
18b) Lightbulb sea squirts
18c) They have a very basic dorsal chord, the forerunner of the backbone in more advanced animals

19a) Yes!
19b) Lions mane
19c) Young whiting, or other members of the cod family

20a) Conger eel
20b) Conger conger
20c) Deep water in the mid-Atlantic

Give yourself 1 point for every correct Shallow answer, 2 points for a Middling and 3 points per Deep answer, for a possible 120 points.
If you got fewer than 10 points youre barely paddling, but if you got most of the Shallow answers and perhaps a number of the others right, anywhere between 20 and 40 points shows that youre reasonably sound when it comes to basic UK marine life ID.
If you got 50-80, people will say of you that youre deep - you know your stuff. They may want you as a buddy. And if you got anything over 90, youre probably a marine biologist.
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