Macro
Seahorses and frogfish on Mount Irvine Wall, flamingo tongues on every sea fan, banded shrimp in the sponges, and octopus and squid after dark.
Background photo: Megan Applegate (Tobago)
Small fish
Look slowly, close to the reef
Mount Irvine Wall, on the sheltered Caribbean side, is the macro site most often named: seahorses, frogfish, arrow crabs, octopus and the shortnose batfish (DAN Alert Diver; DAN Alert Diver; Scuba Diving).
Key marks: A round body with a huge upturned mouth, hand-like pectoral fins and a lure on the snout; dark spots, some ringed in white, usually three on the tail. Up to about 20 cm, and often looks like a sponge (Naturalis Caribbean Diving).
At Tobago: Frogfish are “sometimes seen” at Mount Irvine Wall (DAN Alert Diver); the source doesn’t name the species, and the longlure is the Caribbean’s most familiar one.
Divers report “resident seahorses” on Mount Irvine Wall (Dive Worldwide), and a large orange seahorse was seen there (DAN Alert Diver). No source found names the species. For comparison, the longsnout seahorse (Hippocampus reidi), the seahorse of Bonaire’s reefs, has a snout about a third of its body length, a gripping tail and bony plates, and is yellow, orange, brown or black (bonaire.com).
Key marks: A pale bluish-grey body with pale blue dots and a yellow head, up to about 10 cm, hovering over a pebble-lined burrow. The male broods the eggs in his mouth (Naturalis Caribbean Diving).
At Tobago: Named by a diver on Tobago’s reefs (Scuba Diving).
Key marks: A bottom fish whose partly see-through pectoral fins fan out like wings, with bright blue tips; up to about 50 cm. It digs in the sediment for prey with one pectoral fin at a time (Wikipedia).
At Tobago: On the sand at Kariwak Reef, with Christmas tree worms on the coral (DIVE magazine).
Invertebrates
On gorgonians, sponges and sand
Key marks: A small snail, 2–4 cm, whose cream mantle has orange, roughly square spots outlined in black; the shell underneath is plain cream. Feeds on sea fans and other gorgonians (anemoon.org).
At Tobago: “As common as sand in Tobago,” says one diver, who also found its relative the fingerprint cyphoma at Sleeper (Scuba Diving).
Key marks: Ruffled, folded flaps along the back, blue to green with purple or red edges (Smithsonian Ocean). It keeps chloroplasts from the algae it eats working for up to four months (Smithsonian Ocean).
At Tobago: Named on Tobago’s reefs as the “lettuce leaf nudibranch” (Scuba Diving); green Elysia slugs were seen at Arnos Vale (DAN Alert Diver).
Key marks: See-through, with red-and-white bands on the body and the big third pair of legs, white antennae and other legs; up to about 6 cm. It waves its long white antennae to call fish in, then picks parasites and damaged tissue off them (Wikipedia).
At Tobago: In the barrel sponges at Japanese Gardens (Dive O’Clock).
Key marks: A triangular body drawn out into a long spiny snout, very long thin legs, fine dark lines on the shell and violet claw tips; 2.5–5 cm, at 3–40 m (anemoon.org).
At Tobago: Mount Irvine Wall, with candy cane shrimp (Scuba Diving).
Key marks: Colour changes constantly, often brown patterning over blue-green, and can flash white; 25–50 cm, active at night at 5–30 m (Naturalis Caribbean Diving).
At Tobago: A 2-ft (60 cm) Caribbean reef octopus was seen at Kelleston Drain (DAN Alert Diver); octopus also hunt in the open at Mount Irvine Wall (Scuba Diving).
Key marks: A broad squid with fins along the whole length of the body, often mistaken for a cuttlefish; brown by day, changes colour fast and travels in small schools in the shallows (The Cephalopod Page).
At Tobago: Reef squid and slipper lobsters on night dives (Scuba Diving).
Night
Night dives
Night dives bring out reef squid and slipper lobsters (Scuba Diving). Goat Island, off Speyside, is dived at night at 12–20 m (40–65 ft) (DAN Alert Diver).
Hands off
Don’t touch, move or hold marine life, including to set up a photo, and keep fins off the reef.
Credits
Where the photos were taken
The photos are Megan Applegate’s own, © Megan Applegate, all rights reserved: the banded coral shrimp and the hero background at Tobago in November 2024, the others of the same species on Bonaire in December 2024. Species without a photo link to photos online.
| Species | Photographer | Licence | Source |
|---|---|---|---|
| Lettuce sea slug | Megan Applegate | © Megan Applegate, all rights reserved | Photographer's own photo, taken at Bonaire, December 2024 |
| Banded coral shrimp | Megan Applegate | © Megan Applegate, all rights reserved | Photographer's own photo, taken at Tobago, November 2024 |