AQUATIC LIFE IN THE GILIS
When you dive around the gilis, especially at certain dive sites like Turtle Heaven, you can be 99.999% certain that you will encounter a sea turtle. There are two types of turtles that can be seen while diving around the Gili islands: Hawksbill turtles and Green sea turtles. You can see the difference by looking at their noses and their shields.
The green turtle is one of the largest sea turtles. Green turtles have shells with beautiful pattern and their noses are round. They’re in fact named for the greenish colour of their cartilage and fat, not their shells.
The sharks that you are most likely to encounter when you are diving around the Gilis are white tip reef sharks and black tip reef sharks.
The white tip reef shark is the only shark from the requiem shark family that doesn't need to stay in the current or swim in order to breathe. They can let the water pass through their gills without moving and filter out the oxygen. This is why you can often find them resting on slopes or under coral overhangs during the day. They’re easily identified by the slim body and the white tip of its fins.
Black tip reef sharks are more shy. Most of the time when we encounter them, they’re swimming around or swimming away rather than resting.
Named for its narrow head and sharp, bird-like beak, hawksbills can reach into cracks and crevices of coral reefs looking for food. Their diet is very specialized, feeding almost exclusively on sponges. Hawksbills are considered Critically Endangered around the world by the IUCN Red List.
Biologists think pufferfish, also known as blowfish, developed their famous “inflatability” because their slow, somewhat clumsy swimming style makes them vulnerable to predators. In lieu of escape, pufferfish use their highly elastic stomachs and the ability to quickly ingest huge amounts of water (and even air when necessary) to turn themselves into a virtually inedible ball several times their normal size.
Porcupine fish can inflate their body by swallowing water or air. When they are inflated their sharp spines stick outwards. And on top of this, there are also some poisonous species. The story that they can inflate only a few times in their lives is not true as long as they inflate underwater. If they inflate on the surface they might swallow air which is a lot more difficult to get rid of - and thus more dangerous.
Peacock Mantis Shrimp
Its body is bright green and blue, with blue head, yellow and red thoracic limbs and red-edged blue telson. These crustaceans have the most complex eyes in the animal kingdom, containing millions of light-sensitive cells. It can move each eye independently and uses this exceptional eyesight to avoid predators and track down prey. A mantis shrimp’s punch is no joke: a blow from a mantis shrimp can easily break through the shell of a crab or mollusc.
Giant Moray Eel
Impressive and very heavy bodied, sometimes as thick as a human thigh and reaching a weight of over 30 kgs. Its serpent-shaped body has a brownish background colour. In spite of their large eyes, they are not able to see very well. However, their sense of smell is extremely good, enabling them to find prey. Moray eels are among the few types of fish that are able to swim backwards.
Cuttlefish rely on their incredible camouflaging abilities to avoid predators, changing colour almost instantaneously to match their surroundings, even though they are colourblind. Changing colour is a nifty trick, but accurately replicating the shape and texture of the nearby coral or seaweed gives the cuttlefish an additional layer of camouflage. Cuttlefish can see behind them.
Octopuses are sea animals famous for their rounded bodies, bulging eyes, and eight long arms. Octopuses are the most intelligent invertebrates on Earth. They have 3 hearts and their blood is blue in colour. They can change their colour and texture of the skin to blend with the surrounding environment and become invisible. They will eject dark ink that will confuse the predators and give them a chance to escape.
Nudibranchs are commonly called sea slugs, but they are not of the same family. There are more than 3000 described species and many undescribed as well. Most of them are bottom crawlers but there are a few exceptions that spend their life floating. Some of them are toxic and most of them scare off predators by their bright colours. Nudibranchs are hermaphroditic and have both male and female reproduction organs but can not fertilize themselves.
False clownfish are also called clown anemonefish or - after the famous movie - Nemo. Before they inhabit an anemone they perform a kind of 'mating' dance- touching the anemone with different parts of their body.
They have a layer of mucus on their body that makes them immune for the lethal sting of the -fish eating!- anemone. All clownfish are born male. They only switch sex if the biggest (dominant) female dies, to become the new dominant female of a group (and can not change back). Very convenient as they tend to live more or less in the same spot their whole lives.
Very unusual and interesting fishes. They can be easily identified underwater by their rigid body, made up of semi-fused but well defined hexagonal bony plates: a truly armoured boxlike strong casing with holes through which emerge the eyes, the mouth, the gilis and the fins. Despite an understandable lack of flexibility, boxfishes are surprisingly agile and can be quite fast swimmers.
They commonly live among rocks, scorpionfish are perchlike fish with large, spiny heads and strong, sometimes venomous, fin spines.
They often lie quietly at the bottom, and many blend closely with their surroundings by virtue of their colouring.
The blue-spotted stingray doesn’t like to be covered in sand like other species of stingray do. Instead, it prefers to show off its beautiful blue spots. they’re easily recognised by the large electric blue spots on the body and pairs of blue stripes along the tail. Bluespotted Fantail Rays have large protruding eyes, and venomous spines positioned well back on the tail
Lionfish are famous by their beautifully coloured bodies, covered with red, white, orange, black or brown stripes (it depends on the species). Stripes are arranged in zebra-like pattern.
Lionfish have feathery pectoral fins that are used to attract smaller prey. On the other hand, the same features keep the predators on the safe distance.