Open Ocean

The vast and beautiful open ocean of the tropics is the largest ecosystem on the planet...


Class Scyphozoa: 'True Sea-jellies'

Order Semaeostomeae

These jellyfish usually have four arms, but are most recogniseable by the long long wispy tentacles trailing from the bell. The edges of the domed bell are scalloped.

Family Ulmaridae

(Kakaban, Indonesia)

Aurelia aurita, 'Moon Jellyfish'.

Order Rhizostomae

These sea-Jellies have eight 'fluffy' divided arms hanging from the bell, rather than the thin wispy tentacles seen on other jelly fish.

Family Mastigiidae

(Kakaban, Indonesia)

Mastigias papua, 'Spotted Jellyfish'.

Cassiopeia ornata, 'Upside-down Jellyfish'.

Class Chondrichthyes: Sharks & Rays

Order Orectolobiformes: Carpet Sharks, including 'Wobbegongs'

Family Ginglymostomatidae

(Talbot Bay, Australia)

Nebrius ferrugineus, 'Tawny Nurse Shark'.

Family Rhincodontidae

This family only contains one living species...

(Cenderawasih Bay, Indonesia)

Rhincodon typus, 'Whale Shark'. The biggest fish on the planet.

Class Osteichthyes: Bony Fish

Order Tetraodontiformes

This group contains various families of mostly unusually shaped fish such as Boxfish, Pufferfish and Sunfish.

Mola spp.,'Sunfish'

The author Damon Ramsey with the largest bony fish in the world (photo by Mark Steadman)

There are three species of Sunfish. They look like giant heads with tails, and often bask sideways at the surface of the ocean. They are the heaviest bony fish in the world. The most widespread is the Mola Mola 'Sunfish' found in tropical and temperate oceans around the world. Mola alexandrini, 'Southern Ocean Sunfish', 'Bump-head Sunfish' is found around south-west Pacific.

Order Beloniformes

Family Exocoetidae: 'Flying Fish'


The following species of flying fish I have given some common names based on the survey book 'Flying Fish'. However, taxonomy on flying fish is unresolved and there are no field guides as such, so take all of these names with a BUCKET LOAD OF SEA SALT - they are just guesses! 

Cheilopogon sp.'Yellowband Flying Fish'.


? 'Leopardwing'


? 'Pink-winged Apache'

? 'Black-eyed Pinkwing'


? 'Freckled Pinkwing'

? 'Rosy-veined Clear-wing'


? 'Solomon Cerulean Flying Fish'.


? 'Pink-tailed Clearwing'


? 'Blue Bandwing'

Class Reptilia

Order Testudines: 'Turtles' and 'Tortoises'

Family Cheloniidae

(off the Lacepede Islands, Australia)

Chelonia mydas, 'Green Turtle'.  Widespread throughout the world's tropical and warm temperate seas.

Class Aves: Birds 

Family Laridae: Terns and Gulls


Onychoprion anaethetus, 'Bridled Tern'.

Family Phaethonitidae: Tropicbirds


Phaethon lepturus, 'White-tailed Tropicbird'.


'White-tailed Tropicbird' in the surface of the water.

Family Fregatidae: Frigatebirds

Rio, Brazil

Fregata magnificens, 'Magnificent Frigatebird'.  Found around South and Central American ocean waters.

Cetacea: whales and dolphins

Parvorder Odontoceti : Toothed Whales

(Papua New Guinea)

Stenella longirostris, 'Spinner Dolphin'. This species probably includes many species; as the very least there are many distinct forms around the world. In the middle of the Pacific Ocean, far away from land, I have seen very tiny forms of Spinner Dolphins.

'Bottlenose Dolphins'

The 'Bottlenose Dophin' is now usually considered to be three or even four different species. Two occur across larger areas of the tropics, with the larger 'Common Bottlenose' Tursiops truncatus, being more widespread and also found in deeper more open water. The closer they examine these two species, the less closely related they seem to be.

Tursiops aduncus, 'Inshore (Indo-Pacific) Bottlenose Dolphin'. Usually found in coastal waters, around the Indo-Pacific oceans. 

Parvorder Mysticeti : Baleen Whales

(Kimberley coast, Australia)

Megaptera novaeangliae, 'Humpback Whale'.

Places to experience the tropical open oceans

include Cenderawasih Bay and Kakaban in Indonesia, and off Donsol Philippines.

Search google and this website: