Endemic Species and Speciation
Of the marine species found around the Hawaiian island chain, around 25% are endemic species, while close to 50% are native species that can also be found in the Indo-West Pacific region of the Pacific Ocean. The species that are endemic, or not found anywhere else in the world, were most likely brought to the islands by ocean currents and then stayed at this new environment long enough to speciate. These new species were then so well adapted to the islands marine environment that they stayed until the present. The Hawaiian islands have some of the highest amounts of endemic species of any islands in the Pacific. Sadly, invasive species and loss of habitat have seen these numbers drastically decrease. As ocean temperatures and pH continue to change at a rapid pace due to climate change and carbon dioxide levels in the atmosphere, coral reefs will continue to die off, leaving less and less unique habitat for the endemic species to call home.
Hawaii’s marine life is diverse and between 15-25% is endemic- meaning the species are only found in Hawaii. There are also many endangered and rare marine animals to find on the Hawaiian islands. For example, the monk seal is one of the most protected and endangered marine mammal in the world and is found on the Big Island. Hawaiian Green Sea Turtles are also endangered and beloved by Hawaiians. They are found on the Big Island and frequently spotted on the Kona Coast. For the visiting scuba divers and snorkelers, the Kona Coast also has the highest concentration of near shore coral reefs. However, due to the relative youth of the Hawaiian Islands, the coral in Hawaii is not very diverse or vibrant in colors. To make up for the coral, the reef fish are vibrant and diverse! The reef fish are up to 25% endemic and on the Big Island, it is common to see masses of yellow tangs, milletseed butterflyfish, or some saddle wrasse. The invertebrates- anything with a spine- are around 20% endemic. Hawaii is known for cowries and some rare cowries found on the Big Island can go for a few hundred dollars a shell.
Fun Fish Facts
The Hawaiian Cleaner Wrasse (1) sets up a “shop” near a coral reef. Then, they move up and down to show the other fish that the shop is open. Now, other fish come to the shop for dead tissues, mucus, and some parasites to be cleaned by the Hawaiian Cleaner Wrasse. The Humuhumunukunukuapua’a (2) is also known as the Reef Triggerfish which is usually very shy, but if it is guarding a nest, then it will potentially bite snorkelers. A Black Triggerfish (3) appears all black from far away; however, once you get closer, neon blue and green stripes are visible radiating from its eyes. Trumpetfish (4) are long and thin from above, long and thick from the side, and almost completely invisible from the front. Also, they can change color and add horizontal and vertical lines in order to blend in with their surroundings. A Parrotfish (5) is one of the most interesting fish in the reef. The male parrotfish keep multiple female partners, and once the male dies, the alpha female switches sex and becomes the man.
(1) (2) (3) (4) (5)
The Importance of Fish in Hawaiian History:
For Ancient Hawaiians, the ocean has become a deeply personal and spiritual place where Hawaiians have learned to cultivate its plants and animals and conserve its resources. Seafood provided the primary protein in the Hawaiian diet, whether it was eaten live, raw, baked, boiled, dried, or fermented, and was commonly paired with taro, sweet potato and breadfruit. The traditional ahupua’a system that divided the Big Island into pie slice-shaped districts ensured that each district had access to the sea. Fishing communities supplied fish, seaweed, and salt to the farmers, making them valuable members of society. Fishermen were known to possess mana kupua, which is the supernatural power to attract fish and encourage reproduction. In addition, each fisherman was famous for each of his/her victories with notable catches including the eel, octopus, or shark. Within Hawaiian culture, fishing legends permeate folklore and common tales including Maui, who took his hook and bait and ended up pulling up an island, and Ku’ula, who used his special pearl fish hook named Kahuoi. As fishermen cultivated special relationships with the sea, they became very skilled at locating fish, spearing fish, and setting up traps, often using the moon’s phases to guide their practices. Some common techniques include the hook and line, cowrie shell lures, spear fishing, especially at night, woven basket traps, and net fishing.
Today, Hawaiians continue to fish as a way to relax, connect with ancestors, and sometimes capture their daily food supply. However, studies show that overfishing has become the primary cause of reef fish declines across the Hawaiian Islands, according to data collected since 2000. Many important reef fish species have declined by more than 75% across the islands. In the coral reef ecosystem, reef fish are key in maintaining healthy coral reef systems because they graze of algae and keep corals from collapsing. Currently, around ⅓ of Hawaiian residents identify themselves as fishermen, often fishing for recreational purposes and underreporting their catches. In the future, marine protected areas that promote no-take or no-use zones where fishing is illegal or community-managed fisheries that encourage accurate reporting provide solutions to overfishing in Hawaii. Communities must work together to use their long history of knowledge of the ocean to guide future marine resource management.
There are some species of harmful marine life that people should be aware of before entering the ocean. Sea urchins are dangerous to step on because of their venomous spines. If you step on one soak your foot in warm water to break down the toxins, and soaking it in vinegar can help to dissolve the calcium carbonate spines. Sea urchins are very common, so be careful where you step. Deadly sea snails are potentially deadly, but no one has ever died from them. The snails have a harpoon like tooth that has a neurotoxic venom and causes a painful sting. The probability of finding one is very low unless you are actively looking for their shells, and there are much more harmless snail species than there are dangerous ones. As a precaution, do not pick up snail shells unless you know it is not dangerous. Jellyfish stings can be extremely painful and last for as long as 8 hours. If you are stung by a jellyfish, remove the tentacles, pour vinegar on it, and soak the area with hot water. Vinegar helps prevent more venom from releasing, and applying heat causes less red blood cells to die. Do not pee on the sting, as it is a myth and can actually cause more pain. Venomous fish like to hide in small areas, so don’t put your hands under rocks, ledges, or near small holes.
Tourism is one of the main contributors to coral reef destruction, and it is also one of the most preventable. When snorkeling it is always important to remember the following rules:
1. Don’t Touch the Coral
a. A thin mucus covers corals, which help to fight off infections, prevent the coral from drying out, and protect the corals from harmful UV rays. Touching the corals can wipe off the mucus, and therefore expose the coral to the above conditions.
2. Don’t Feed the Fish
a. Feeding the fish causes them to associate humans with food, and to become more vulnerable to predators. It also disrupts the usual feeding cycle present in marine communities.
3. Don’t Chase the Fish and Swim Slowly
a. Chasing the fish and splashing around can cause stress for the fish and coral.
4. Don’t Remove Anything from the Water (except trash)
5. Use a Biodegradable Sunscreen
a. Chemicals from sunscreen can come off in the ocean and cause coral reef bleaching. Oxybenzone is a common chemical found in sunscreen, that has been proven to be toxic to algae found within corals.
By following these steps, damage being done to coral reefs can be significantly reduced. Even when you’re not in the water, steps can be taken to help conserve coral reefs. Spreading awareness, supporting environmental groups, writing to government officials, and voting can all significantly help in coral reef conservation. For more ways to get involved, you can check out the following groups and representatives:
➔ National Oceanic and Atmospheric Administration ➔ Madeleine Z. Bordallo- and her Coral Reef Conservation Reauthorization Act
➔ Project AWARE ➔ David B. Cohen- and his Coral Reef Conservation Act
➔ Coral Guardian ➔ Coral Reef Alliance