Kauai Information > Kauai's Fish and Sea Life

The ocean surrounding Kauai is a world of adventure, surprise and awe. It is amazing to consider an entire world with which we are so unfamiliar. Kauai’s underwater world is pure pleasure. Because northshore Kauai is on the Anini reef, snorkeling provides an ever-changing show. Snorkeling in varying locations provides a glimpse into the lives of varying types of fish. Sitting on the beaches and watching the deeper waters will be rewarded with views of deeper water fish as they feed, play and jump above the ocean surface. While you’re out snorkeling or enjoying yourself in the ocean, you might run across a certain fish or ocean critter that will suddenly surprise you. Keep in mind, all Sea Turtles (and Seals, Whales and Dolphins) in Hawai'i are fully protected under State Law and the U.S. Endangered Species Act.

Popular ocean life you may see are:

Dolphins are found relatively everywhere. Hawaiian Spinner Dolphins remain near the Islands all year where they feed, mate and look after their young. The Dolphins feed at night in the open ocean, usually along the 100 to 1000 fathom escarpment, where they forage on organisms that rise to the surface such as small squid, hake and lantern fish. Dolphins are often seen "riding the bow" of boats around the Main Islands. Individuals can often be seen jumping and spinning right out of the water - hence their name. Dolphins can be seen from many of the States headlands, such as Kilauea Point on Kaua'i. Their Hawaiian name is Nai'a. Going on boat rides are the best way to see and possibly swim with the amazing dolphin.

Green Sea Turtles, in Hawaii, are called Honu. They are a threatened species and protected in Hawaii. This is one of three Turtle species native to Hawai'i. Occasionally, Hawksbill and Leatherback turtles can also be spotted. Turtles take a long time to reach sexual maturity - an average of 25 years, but up to 40 or 50 years. Males can be distinguished from females, when adult, by the presence of a long tail extending past the back flippers; females only have very short tails, which extend just beyond the shell. Every 2-5 years they migrate over thousands of miles of ocean to mate and nest. Turtles eat mainly vegetable matter such as algae and can grow to a breeding size of over 200 pounds or more. A good place to see lots of turtles is the Kilauea Lighthouse and Kalapaki Bay. Females may visit several times in a single year to nest, but wait two or three years before nesting again. About 100 eggs are laid at a time and the female then covers the eggs with sand. These eggs take about two months to incubate.

Once the hatchlings are out of their shells they work as a team to break through the sand piled on top of them. When they reach about an inch from the surface the hatchlings stop if the sand is hot, as this tells them that it is daytime. If it is cool, they continue digging as this signifies night or an overcast day. Once through the sand, they race for the water and swim constantly for the next 36 to 48 hours. They then grow alone for the next few years, living off invertebrates such as jellyfish, before joining the female and juvenile Turtles at coastal feeding grounds. When swimming with them, don’t hang on to them, it could cause them to drown.

Leatherback Turtle - This species does not nest on or usually come close to Hawai'i's shores but it is regularly seen offshore over deep water where it feeds on jellyfish and other invertebrates. Leatherbacks are the only Sea Turtle that do not have a hard shell or claws on the anterior edge of its flippers. Weighing up to two thousand pounds they are the giants of the World's Sea Turtles.

Hawaiian Monk Seals are the most endangered seal species in the world. If you see a seal, observe and take pictures a good distance away. The Hawaiian name for the Monk Seal is 'Ilio holo kai which means "the Dog that runs in the sea". An adult monk seal is usually dark gray or brown with a light Grey or yellow belly. Adults can weigh anywhere from 396 to 595 pounds; adult females are generally larger than males. Pups usually weigh 24 to 33 pounds at birth and weigh up to 132 to 198 pounds within five to six weeks. The monk seal's common name is derived from its folds of skin that look like a monk's hood, and because it spends most of its time alone or in very small groups. The life span of the Hawaiian Monk Seal is from 25-30 years. Monk Seals prefer sandy beaches and lava benches where they can haul themselves out of the water and rest and digest their food. Prey items, which they like to feed on, include bottom and reef fishes, lobsters and eels and most foraging occurs in water less than 90 meters deep, but has been recorded at a depth of 500m! Monk Seals are often faithful to their birth site and may return year upon year to give birth or feed and rest. Mothers stay with their pups from birth to about five or six weeks, never leaving them unprotected to go feed. During this time, she will lose as much as 300 pounds in weight. When she finally departs, the pup is on its own to learn to catch food. They spend most of their time in the ocean but like to rest on sandy beaches, and sometimes use beach vegetation as shelter from wind and rain. Monk seals are expert swimmers and divers; one seal was recorded diving into depths in the range of 66 and 96 fathoms (396 to 576 feet). The average monk seal dives 51.2 times per day.

Sharks may not be commonly seen but they are out there. There are several species. Some species can be a threat and others aren’t.

Rays have flattened bodies. Their skeletons are made of cartilage. They aren’t commonly seen.

North Pacific Humpback Whale - are an endangered species which migrate to Hawai'i from their Alaskan summer feeding grounds. Its Hawaiian name is Kohola. Humpbacks come to Hawai'i to give birth and mate. Whales can be seen between December and April, where they frequently put on an amazing show. Good sites to look for them is Kilauea Point Lighthouse. Powerful binoculars are loaned by the park service for your viewing pleasure. A little known fact is that all Humpbacks, while in Hawaiian waters, sing the same song, which changes over the season.

Eels live in crevices and holes. They are normally encountered by divers and snorkels.

Octopus are found in dark places. They are extremely hard to see because they have such great camouflage.

Angelfish are a favorite of divers and snorkels. Even though they are often friendly some can be territorial. Some species aren’t commonly seen.

Butterfly Fish are typical reef fish. They travel in pairs and are brightly colored.

Damsel fish are found in shallow tropical water. There are two kinds: Plankton or algae eaters. Hawaii lacks the brightly colored ones.

Goatfish are normally the first fish seen by snorkels because they’re easily recognizable. They are able to change color dramatically.

Groupers have heavy bodies and large mouths. The larger ones are curious and intelligent.

Needlefish are long and slender. They eat small fish. There’s at least 4 species in Hawaii.

Parrott Fish are herbivorous. There are 7 species.

Tang fish (convict tangs pictured left) are the most numerous and prominent of all Hawaiian reef fish. They are typically oval in shape and have thin bodies. They are shallow water creatures

Triggerfish whose Hawaiian name is Humuhumu-nukunuku-a-pua'a ("snout like a pig" ) got their name because of the arrangement of the dorsal fin. Triggerfish are probably the best known of Hawai'i's reef fish and is a beautifully colored species which can be easily seen in tidal rock pools and on coral reefs. They have tough skin.

Yellow-finned Tuna also known as 'Ahi in Hawai'i, is a large fish popular with fishermen and is served in most restaurants in the Kauai. 'Ahi are a good species to look out for when looking for seabirds as they drive smaller fish to the surface which the seabirds prey upon, in most cases of course, the birds will be spotted first, but some radar systems will pick up larger 'Ahi shoals. Yellow-finned tuna are pale gray overall with distinctive yellow fins. They are common in Hawaiian waters.

Skipjack Tuna is another popular fish found in Hawaiian waters and is also often seen from fishing boats. The species is known as 'Aku in Hawaiian.

Dolphin Fish are also popular with the fishermen and is common in Hawaiian waters. The species can grow to a large size too, although not usually as large as 'Ahi. Dolphin fish are also pale gray in color but has a distinctive head shape, which is very rounded. Known as Mahi’mahi in Hawaiian.
Wrass are slender, fast moving, common reef fish. They are recognized by their bright gaudy color patterns. Hawaii has over forty species.

So, when asked, is there enough to do on north shore Kauai for a week, be informed, you can spend months just locating different varieties of Kauai sea life.