LAND AND MARINE LIFE

Sea turtles are reptiles. There are only 7 marine species world wide out of the 225 species of turtles that live today. Brain size may not have anything to do with longevity considering the turtle’s brain is smaller than a grape, and it has survived 225 million years. The largest turtle ever swam in the ancient seas that covered Kansas and South Dakota, weighed over 6,000 lbs. and its shell measured 12 feet in length. We see these curious sea turtles along our route off shore Kauai.

There are three native Hawaiian sea turtles. The Green turtle, or Honu, is the most common. There are very small numbers of Hawksbill, or Ea, found around the islands of Molokai and Hawaii. The third turtle is the most rare, the Leatherback, and it is usually seen on the open ocean where it feeds almost exclusively on jelly fish. There was one documented case of a Leatherback laying eggs on the shores of Kauai four years ago – high surf washed the eggs away

The Green sea turtle is threatened which means it isn’t likely to go extinct as the Hawksbill and Leatherback which are both endangered . However, all of the sea turtles are federally protected and the penalties are severe if you bother these turtles in any way.

The fat of a green sea turtle is yellowish green  and turns bright green when cooked (probably due to the green plant food that makes up the diet of an adult sea turtle).

Yes, there are between 6-8 nesting females that lay their eggs on both the north and south shores of Kauai. The females are on a two year nesting cycle and usually lay over a hundred eggs every two weeks from the end of May to September (a total of 1200-1400 eggs in a season!).  Most of the green turtles swim over 800 miles to nest on the French Frigate shoals which are apart of the North West Hawaiian Islands.

The male uses his tail to hold onto the female during copulation, turtles are known to copulate for hours. It is thought that during this time the couple emits some type of shark repellent because sharks will not bother copulating turtles. Often, the male is fertilizing next years crop of baby turtles because the female can store the sperm for more than a year (this is common ability for reptiles).

The male uses his tail to hold onto the female during copulation, turtles are known to copulate for hours. It is thought that during this time the couple emits some type of shark repellent because sharks will not bother copulating turtles. Often, the male is fertilizing next years crop of baby turtles because the female can store the sperm for more than a year (this is common ability for reptiles).

Dr. Don Heacock from Aquatic Resources on Kauai gets a call once a week about a green sea turtle entangled in some type of fishing line or net. Only 10% of these turtles survive, which means we lose around 50 turtles a year to nets alone. The ones that don’t get tangled in nets, may die from ingesting plastic bags, pieces of plastics, or die from the dreaded disease fibropapilloma.

In humans a papilloma tumor is a benign growth that is spread by a virus, i.e. an ordinary wart. When they develop predominantly on fibrous tissues, they are called fibropapillomas. Fibropapilloma only attacks green sea turtles and these tumors debilitate and disfigure the turtle within a few years. These tumors are lobe shaped and grow on all soft parts of the turtle. Scientists do not know what causes this disease. They only know that it is a viral infection and it is caught in the wild (captive turtles don’t contract the disease even when in close contact with diseased turtles). Green turtles in Florida and the Bahamas are also suffering in epidemic proportions from this disease. It is feared that if a cure is not found soon for this disease that it may wipe out this species of sea turtle completely. 10% of the green sea turtles tagged off Kauai have fibropapilloma compared to over 90% of the greens tagged off Maui. It is not known how this disease is spread but it would appear that females maybe more likely to contract the disease than males (at least, this is true for the turtle population in Maui).

There have been 7 documented cases of green sea turtles dying from vessel impact over the last 10 years. Most of these turtles were found having seaweed in their mouths which means they were hit when they were feeding. Two of the cases were turtles that washed up in Haena. Whether these turtles were hit by commercial boats will never be known. According to Dr. Heacock, “Speed kills and it is important, to drive slowly and safely where turtles are known to be resting and feeding along the Na Pali Coast.”

The slim spinner dolphin averages between 5-7 feet and its weight ranges between 110-160 pounds. There are three parts that make up the color pattern of the spinner; a dark back, pearl-gray side panels, and pure white belly. Their long, slim, blackish beaks are lined with 180 or more delicate interlocking conical teeth.

Spinners eat a lot of very small food items: two-inch, bioluminescent lantern fish, deep-sea shrimp, and thumb-sized squids. Some of these squids never venture closer than 500 feet to the surface of the water. Spinners can dive to almost 1000 feet hunting for food.

On average, newborn dolphins are most abundant in the late spring and summer, pregnancy lasts about 10.5 months and the babies are born within the school of dolphins. It is speculated that sexual behavior in these dolphins might be cued chemically probably by taste during mating season (late spring and summer). Females cycle through very brief peaks of sexual readiness (females who just ovulated), lasting just days. The male hormone patterns are quite different and they are sexually active throughout  much of the mating season.

Yes, they can have twins but less than 1% have twins. Other adult females within the dolphin school will take care and feed the baby.

On the average, 20 years of age.

There are 78 species of whales, dolphins and porpoises and the scientific name is Cetacean (pronounced se-TAY-shun) which comes from an ancient Greek word “ketos” meaning whale. All whales are mammals and they breathe air, give birth to live young and nurse their young with milk. There is amazing diversity from the largest adult Blue whale which is 20,000 times heavier than the smallest newborn Vaquita porpoise. Modern cetaceans carry with them remnants of their terrestrial (land) ancestry. If one examines the internal structure of a whale’s side flipper-it resembles a huge hand complete with finger bones. Most whales also possess internal remnants of a functionless pelvic bone and hind leg bones. Whales evolved from hoofed land mammals about 50 million years ago.

A whale is a mammal similar to a land mammal except that is lives in the water, specifically the ocean, which is very salty. So ocean mammals have evolved differently than land animals. Ocean mammals cannot breathe oxygen out of the water like fish. Ocean mammals, like whales, have to come to the surface to breath. Respiration is an exhausting activity and energetically expensive for mammals that have the same kind of lungs as human beings do (they’re called ventilation lungs) except that whale lungs are extremely efficient. With each breath the whale takes, there is over 90% exchange of the content (carbon dioxide for oxygen) of its lungs, a respiratory rate 5-6 times more efficient than human lungs. The lungs of a humpback whale make up only 1-3% of their total body weight vs. 7% in a human.

In a medium of water, the whale is able to grow to huge sizes. In fact, the Blue whale is almost twice the size of the largest dinosaur that ever lived on Earth. It averages 100 feet in length and can weigh from 120-150 tons. You can think of a Blue whale as being as long as 3 railroad cars and weighing as much as 1600 people or 30 elephants. Whales, especially the Humpback whale, have very thick layers of fat or blubber (6-8 inches) which keeps them warm in polar waters and helps them float. The fatty tissue provides enough buoyancy to offset the negative buoyancy of the whale’s muscle and very light skeleton. The bones of a whale will actually float because they are filled with fat (which is quite different than the bones of a seabird which are filled with air). Whales don’t have to worry about supporting their great weight because they are in a medium of water and between their very light bones and built in “fat life preservers” they are very buoyant. But if a whale is beached they have a limited amount of time (depending upon the size) before the mammal will be crushed by its own weight.

The sperm whale, the cetacean with one of the most impressive of all underwater capabilities has been documented as diving over 12,000 feet (more then 2 miles) for as long as 3 hours. It seems that cetaceans are able to take more oxygen down with them than a human diver can. One factor in this performance is the cetacean’s considerably greater volume of blood: up to 2-3 times more blood per unit of body weight than in human beings. The cetacean’s blood also has a somewhat greater oxygen-carrying hemoglobin of the red blood cells) is responsible for the muscle’s characteristic dark red color. Myoglobin is present in the muscles of terrestrial mammals too, but in much smaller amounts than cetaceans. In some cetaceans species more oxygen is carried in the muscles than in the animal’s red blood cells. Another key factor for cetaceans is its highly developed vascular systems – the fast circulation which rapidly reloads the red blood cells with oxygen. This fast circulation is demonstrated by the faster heart rate when a whale comes to the surface to breath after an extended dive. The whale has a powerful heart and a circulatory system that features large networks of capillaries (retia mirabilia or wonderful nets) and large sinuses in the venous system. The ability to recharge red blood cells with oxygen fast constitutes the fundamental respiratory difference between cetaceans and terrestrial mammals, whose breathing is usually regular and whose blood flow is relatively smooth. For example, humpback whale exhales its breath at 300 miles per hour then inhales around 2,000 liters of air per minute.

Yes, it is a type of fish in which the skeleton is made out of cartilage, instead of bone. Cartilage is a flexible, semi-transparent elastic material full of cell spaces. Cartilage is formed from a complex protein which encloses a network of connective tissue fibers. Sharks and their relatives the skates, the rays, and chimaeras, are separated from the 26,000 species of bony fishes, because they are cartilaginous fishes, known collectively as the Chondrichthyes. There are between 344-368 different species of sharks and some have fossils dating back 400 millions years (dramatic compared to man which is only 2 million years).

There are 3 possibilities for sharks. 1) Some species lay eggs usually encased in a leathery shell, they are expelled into the sea where the embryos develop for a period of 6-10 months hatching as miniature adults. This is considered the most primitive mechanism known as oviparous which means egg birth, & it is used mostly by bottom dwelling types of sharks such as the horn & cat sharks. 2) Ovoviviparous, meaning born live from egg, is the mechanism that occurs in the majority of sharks. The eggs develop from the nutrition of the yolk, & the embryos hatch inside the mother, to be born shortly after. With some species the developing embryos will actually feed on the other embryos inside the mother, cannibalizing one another till the most ferocious remain. This is referred to as ovophagy, which means egg eating & occurs with the Mako, Tiger, Sand & probably the Great White. 3) Viviparous, meaning live birth, is the mechanism in which there is a placenta-like growth contacting the embryo’s yolk-sac & provides a channel for transmission of nutrients direct from the female’s blood stream to the embryo (takes 9 months for development). This is the most sophisticated mechanism of development. It occurs in the Blue shark, Oceanic White tip, Black tip reef, Gray reef, & probably all of the hammerheads.

Some species of shark will not hesitate to eat their own young, thus females will not eat at all while they are in the nursery grounds during “pupping” season.

Sharks have been thought to be destined to a life without rest, because some need to swim continuously in order to move water past the gills to oxygenate the blood. However, a substantial number of species are quite capable of resting on the bottom in still water, while muscularly pumping water over the gills. It is probably the case for larger species, including the Tiger shark, Bull shark, and Gray reef shark.

Some species of shark (i.e. Cookie Cutter) lie at the bottom of the sea more than 2 miles deep & then swim up in the evening for feeding.

Sharks are aged by counting the number of rings (annuli) added yearly to the sharks’ vertebral centra (annulus method). It is not an exact method as some species may differ in the number of rings they add each year. The Tiger shark can probably live 50 years & the Great White almost 100 years. The average is close to 25 years of age.

Yes, out of the hundreds of species, there are two that can live in fresh water the Bull & Ganges shark. The Bull shark is found in the Lake Nicaragua, & many rivers; including, Mississippi, Amazon, Ganges, & Tigris in Nicaragua. The Ganges shark is rare & is only found in the Hooghly & Ganges Rivers in India.

The largest shark & fish is the Whale Shark, & it is a filter feeder-practically harmless, similar to a Baleen whale except that it has 1000’s of tiny teeth arranged in over 300 rows. The whale shark feeds on plankton, shrimp & small fish. The average whale shark is around 50-60 feet & weighs 45 tons. The whale shark can have 300 eggs; it is thought to be ovoviviparous meaning born live from egg. The eggs are carried internally until they hatch inside & then the “pups” are born.

The smallest shark is the Dwarf shark or Spined pygmy which averages almost 4 inches in length, the longest recorded was 9.8 inches.

Yes

Shark skin is made up of tiny, hard, tooth-like scales called denticles (denticle means tooth). These denticles have a hard outer layer of enamel & are extremely abrasive. The shark’s “skin teeth” reduces water turbulences & increases laminar flow there by enabling them to move more efficiently in the water.

The Blue shark holds the record 3,740 miles, the distance from New York State to Brazil or a little more than one way trip to Alaska from Hawaii.

The Hawaiians have always had great respect for sharks especially the Tiger & Great Whites. The mana or spirit of the Great White was embodied in the motif represented as an abstraction of the shark teeth (equilateral triangles) woven into the chief’s feathered cloak & also in complex tattoo motifs of the Hawaiian warriors. The teeth from the Great White presented the sharpest & thinnest edge used to cut designs for kappa or bark cloth bamboo stampers, wooden kappa beaters, & decorative bases for drum & gourds. Teeth fastened to heavy wood clubs were formidable weapons. Shark skin produces a leather that has 2-3 times the tensile strength of pig or cow hide & it was used to make head covers of the Hawaiian hula drums.

Thirty-three years ago, people paid to see young men riding on the backs of large Tiger sharks – it was considered a grand tradition of Oahu. It was the shark aquarium which is now a research facility of University of Hawaii to study captive dolphins.

What is the latest in technology for protecting humans from shark attacks? The U.S. Navy has designed and tested the “shark screen” – a large, dark, cylindrical plastic bag which is closed at the bottom, and has inflatable rings around the top. The idea is NOT to have any protruding areas (i.e. arms or legs), or any blood or body chemicals-only a large shapeless image is presented to the shark. “Shark screen” seems to be successful; probably a tent or sleeping bag would work as general survival gear.

“Sea Lions Trained to Film & Tag Whales”, Researchers are training sea lions to become their spies of the deep. A 400-pound, 17-year-old male named Beaver and his 190-pound, eight-year-old female, sake, will take on the mission of videotaping and tagging whales off Monterey Bay. With six years training, Beaver will be the first to scale the ocean depths on hand and acoustic command – perhaps as early as this winter – aiming his video camera as his fellow sea creatures, gathering footage of the secretive giants at work, play, love or war, as never before seen by man. “We’ve got a biased view of what whales do because most observations have been done from shipboard,” said Jennifer Hurley of the Moss Landing Lab, who leads a team of 25-plus behavioral trainers. “In reality, whales spend 90-95% of their time under the sea. We need to know what’s going on down there. The whales are used to seeing sea lions, so by getting sea lions to be our filmmakers, we should be able to record what the whales are doing without any undue outside influence. Sea lions respond well to training and, we think, can learn the complex skills involved in swimming beside whales while wearing a harness with a video camera or carrying a tag in their mouths and affixing the tag to the side of a swimming whale.” The equipment the sea lions carry will allow instantaneous recording of depth, time, sounds and speed of the whales along with the video image. Underwater recordings will be used to analyze diving patterns, speed and underwater behaviors of gray whales, and depth, speed and feeding behaviors of humpbacks.

Unlike other seabirds, they lack substantial oil glands at the base of their tails. Thus they can become very bedraggled and even drown if they alight on the water for more than a few minutes.

The nod die typically lays one egg in the winter and spring, the egg representing almost 27% of the female’s body weight. Black noddies grow the fastest out of all of the terns and noddies, and average 38 days from hatching to first flight.

It is believed that Black noddies live to 25 years of age.

All terns and noddies have ceremonial fish flights in which one bird presents and sometimes transfers a fish to its partner. The nodding and bowing typical of noddies occurs when a male feeds his mate before she lays her egg.