Author: Patricia Greene

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Patricia Greene, July 19, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: July 19, 2006

A large green sea turtle basking in the sand.
A large green sea turtle basking in the sand.

Science and Technology Log

Unlike the spinner dolphins, we have observed the Hawaiian green sea turtles tend to be rather shy and elusive. We managed to catch just glimpses of them from a distance.  Based on past slaughters by man it is no wonder these creatures would avoid contact with humans. Historically, from the late 1800’s until 1970’s these creatures were slaughtered and harvested. Finally, in 1978 turtles were recognized under the U.S. Endangered Species Act however, they are still harvested in many parts of the world.

Several adaptations make the green sea turtle well suited for life in the ocean. Special lachrymal glands in the eye assist in the regulation of salt in the turtle’s body, preventing it from becoming dehydrated. When sea turtles shed tears they are actually removing salt from their bodies. Sea turtles are capable of storing large amounts of oxygen in their blood and muscle tissue, and lungs are adapted for rapid exchange of oxygen. Green sea turtles can stay under water up to five hours. Modified forelimbs give the sea turtle an efficient forward power-stroke. Protective coloration in the form of counter shading and blending gives the sea turtles camouflage. The underneath of the shell is cream color so the turtle blends with the sky and water to anything looking up and has a dark top shell for any predator looking down.Our luck changed on Southeast Island at Pearl and Hermes Atoll in the Hawaiian Islands National Wildlife Refuge. While circumnavigating the island we viewed a large adult green sea turtle pulled out and basking on the beach. After lunch we viewed from a distance two more green sea turtles basking and swimming in the surf. Researchers told us that they often observe 10 to 20 turtles pulling out at sunset and sleeping on the beach at night. It is more common in the Northwestern Hawaiian Islands than the main Hawaiian Islands for green sea turtles to exhibit this basking behavior. It is thought the behavior may be an adaptation to the cooler waters (i.e., a mechanism of thermoregulation, or a predation avoidance strategy due to the high populations of tiger sharks).

Three endangered Hawaiian green sea turtles bask on Southeast Island in the Hawaiian Islands National Wildlife Refuge.
Three endangered Hawaiian green sea turtles bask on Southeast Island in the Hawaiian Islands National Wildlife Refuge.

Green Sea turtles reach sexual maturity at approximately 25 to 30 years and reach a weight in excess of 200 lbs. Green sea turtle’s breeding behaviors demonstrate great stamina. Pairs may remain coupled for 10 to 12 hours and both sexes have multiple partners throughout the mating season. Adult males can be distinguished from females by their longer tails and curved claws on their flippers.  After the hatchling breaks out of the shell it must then reach the surface. Hatchlings demonstrate “protocooperation” meaning they work together as a group for several days in a joint effort to reach the surface. The hatchlings take turns digging and resting. Once they are near the surface the heat of the day will immobilize them and they will not continue their escape until the evening temperatures have cooled the sand. In this way they avoid heat stress and predators.Green sea turtles are oviparous (lay eggs externally) in a sand pit on the beach. Nesting starts in May and continues through August. Critical components of the nest site must include: lack of predators, a moist substrate, and suitable temperatures and be located beyond the high tide mark. Typically the green sea turtle will lay 75 to 150 eggs at night, in a clutch and lay multiple clutches during the breeding season. Incubation takes 50 to 70 days depending upon ambient temperatures. Sex of the hatchlings is not determined at the time of fertilization or conception (no sex chromosomes) but dependent upon the temperature of the sand and individual position of the egg in the nest. This is called “TSD” or Temperature-Dependent Sex Determination. The pivotal temperature for the green sea turtle is 28.26 degrees Celsius (82.9 degrees Farenheit). This is the temperature at which equal number of male and female hatchlings will be produced. If the temperature falls below this number more males will be produced; above more females will be hatched.

Now the hatchlings must find their way to ocean, avoiding the ghost crabs of the night. It is thought they employ a variety of visual clues, “wave compass” and perhaps a “magnetic compass” in their effort to reach the ocean. Scientists believe the wave compass allows the hatchlings to get orientated directly against the incoming waves. The magnetic compass refers to the magnetite found within their brains that may align them with earth’s magnetic fields. Once they arrive at sea, they will dog paddle to open water; hiding in algae, drift lines or other floating debris.

A curious Hawaiian green sea turtle approaches underwater at Puako in the main Hawaiian Islands.
A curious Hawaiian green sea turtle approaches underwater at Puako in the main Hawaiian Islands.

During this pelagic stage they are carnivores and feed on plankton. They will remain at sea in this hatchling/early juvenile stage for years, sleeping with their flippers folded over their back to diminish their chance of becoming a morsel for some predator. This stage is a period of rapid growth; perhaps 8 to 10 cm the first year. The young turtles will re-appear in coastal waters where they will continue to grow, graze on algae and become life-long herbivores. The green sea turtle has specialized microorganisms in the hind gut that digest the cellulose in the plant material. It is possible that juveniles establish this flora by practicing “scatophagy” or the ingestion of adult turtle feces.

Another concern for the green sea turtle population has been the appearance of fibropapilloma tumors. Tumors on the eyes, throat, lungs, kidneys, liver and intestines have been documented. Scientists believe a Herpes-type virus may be responsible. The disease is quite common in the mainland Hawaiian Islands but relatively rare in the Northwestern Hawaiian Islands. These tumors may blind the turtle or choke them depending on the location of the tumor.  Fortunately, we did not observe any tumors while we have been in the Northwestern Hawaiian Islands.Typically sea turtles thrive on sea grasses, seaweeds and algae. Depending upon where they live their diets may vary; for example green turtles of the Pacific Ocean are more dependent upon algae and seaweeds than the sea turtles of the Atlantic Ocean that thrive on the sea grasses such as turtle grass. The diet of the green sea turtles at Kure Atoll consist of an algae called Codium edule. In the main Hawaiian Islands invasive alien species of algae in the marine ecosystems have displaced the native species of algae that the turtles have traditionally fed on. This has caused widespread damage to the coral reef habitats.

The Northwestern Hawaiian Islands are extremely important to the green sea turtles. It is one of the last places where turtles are not affected by man’s desire for beach front property; no issues of coastal development, domesticated predators, recreational activities, artificial lights, high speed boat traffic, or general coastal degradation of the habitat. Over 90% of Hawaii’s green sea turtles return to nest at the French Frigate Shoals. Turtles come from the far north end of the Northwestern Hawaiian Islands chain (Kure, Pearl and Hermes, Midway Atolls) and from outreaches of the main Hawaiian Islands to lay their eggs at French Frigate Shoals.

Special thanks to the Hawaiian Islands National Wildlife Refuge, United State Fish and Wildlife Service, Department of Interior for access to Southeast Island and an opportunity to spend a day with the NOAA Fisheries biologists to learn more about the spinner dolphin research they conduct during their field season.

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Patricia Greene, July 16, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: July 16, 2006

The ornate butterflyfish (Chaetodon ornatissimus) is one type of butterflyfish that is also a coral predator.
The ornate butterflyfish (Chaetodon ornatissimus) is one type of butterflyfish that is also a coral predator.

Science and Technology Log

When you think of the Northwestern Hawaiian Islands and predators, the first thing that comes to mind may be the apex predators; tiger sharks, Galapagos sharks and species of huge fish such as the jacks. Corallivores (an animal that feeds on corals) may include fish, sea stars or mollusks.  Generally, two types are recognized; obligate corallivores; those that feed only on corals and facultative corallivores; which feed on corals, algae, sponges, and mollusks.However, while snorkeling the Kure Atoll, I was reminded that there is another group of predators here; the corallivores. I observed a crown of thorns that appeared to be feeding on the coral and upon further research I discovered and recognized a variety of Northwestern Hawaiian Islands creatures that I have seen that also specialize in feeding on corals.

The crown of thorns feeds by inverting its stomach through its mouth, and then digests the corals externally. Human attempts at controlling populations of crown of thorns have been relatively unsuccessful and causes of these population spikes or outbreaks have been a topic of debate. Some believe they are natural occurrences and occur in cycles while other scientists believe they are due to human causes such as increased sedimentation and pollution.The crown of thorns (Acanthaster planci) has cryptic coloration and toxin-filled spines.  It prefers to feed on rice corals (Montipora), lace corals (Pocillopora), and cauliflower corals (Acropora). Ironically, the crown of thorn eggs and larvae are often fed on by the stony corals. Other natural enemies of the crown of thorns is the harlequin shrimp and the fireworm. This little shrimp does not kill the crown of thorns, but merely creates a small, open wound. This is known as “facilitated predation.” The larvae of the fireworm then enter the cavity, reproduce, and the offspring eat the crown of thorns from the inside out; eventually causing death.

The crown of thorns (Acanthaster planci) is a major predator of coral reefs.
The crown of thorns (Acanthaster planci) is a major predator of coral reefs.

We have also observed a variety of butterflyfish on the reefs; all that are also coral predators. The ornate butterflyfish (Chaetodon ornatissimus), the oval butterflyfish (Chaetodon lunulatus), the fourspot butterflyfish (Chaetodon quadrimaculatus), and the multiband butterflyfish (Chaetodon multicinctus), are all obligate corallivores. Other butterflyfish that eat both corals and invertebrates include; the threadfin butterflyfish (Chaetodon auriga) and the teardrop butterflyfish (Chaetodon unimaculatus).

We have also identified the spotted pufferfish (Arothron meleagris) hiding in the corals of Kure Atoll’s lagoon. This unique creature has a beak-like mouth with sharp frontal teeth for removing pieces of substrate and flat teeth in the back for grinding. They feed on a variety of organisms, including the stony corals and calcareous algae. They have a unique adaptation that allows them to lodge their bodies into a crevice or hole and then puff up so it is impossible for a predator to dislodge them. Their tissue is relatively toxic to humans.The shortbodied blenny (Exallias brevis) is an obligate corallivore. It prefers the lobe (Porites lobata) and finger coral (Porites compressa). The spotted color of these fish blends nicely with the colonies of coral. Removing tiny bites these fish have little impact on the health of the corals. The coral colony is able to regenerate new polyps and fill in he bite marks.

The shortbodied blenny (Exallias brevis) is an obligate corallivore, which feeds on coral.
The shortbodied blenny is an obligate corallivore, which feeds on coral.

The blue-eye damselfish (Plectroglyphidodon johnstonianus) inhabits the Northwestern Hawaiian Islands coral reefs. It feeds only on coral, preferring the lace, antler, cauliflower, finger and lobe corals. These small fish are very territorial and will defend their nests, hiding in the corals that also serve as food. Most of the coral predators do not pose any major threats to the coral reefs. They are natural inhabitants of the reefs and do little damage. The crown of thorns can cause mass devastation; during major outbreaks at other Pacific Ocean locations the coral cover was reduced from 78% to 2%. In 1970, approximately 26,000 crown of thorns were destroyed off the southern coast of Moloka`i. However, during all of dives in the Northwestern Hawaiian Islands we only observed two crown of thorns, which is good news for this remote region.

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Patricia Greene, July 13, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: July 13, 2006

Old fishing nets get piled up on the pier on Green Island at Kure Atoll waiting for the marine debris crew to pick up
Old fishing nets get piled up on the pier on Green Island at Kure Atoll waiting for the marine debris crew to pick up

Science and Technology Log

One reason the Northwestern Hawaiian Islands (NWHI) are so unique is that they contain some of the most isolated, pristine, and genetically pure coral reefs in the world.  Kure Atoll is approximately 1,200 miles from the main Hawaiian Islands. It represents one of the last intact, predator-dominated reef ecosystems. It is a critically important habitat to a wide range of species including seabirds, sea turtles, monk seals, and sharks.  The earliest creatures arrived on these islands by swimming, flying, or floating for thousands of miles and then with the passage of time, evolved into genetically different species. These species are referred to as ‘endemic’ meaning they are unique to that area.

Historically, man’s greatest impact on the ecosystems of NWHI has taken two major venues; importation of terrestrial alien or exotic species and mass slaughter or over-harvesting of existing endemic species.  Understanding the past can help us protect the future of the NWHI.Hawai`i has a very high incidence of marine endemism due to the age of the islands (Kure Atoll is approximately 28 million years old) and the relative isolation from other coral reefs. The prevailing currents generally run from east to west; keeping larvae from other reefs from reaching Hawai`i. Also, the waters here tend to be cooler and the wave action intense, deterring foreign species from colonizing. The marine ecosystems have been far less impacted by man than the terrestrial ecosystems. Only 11 aquatic invasive marine invertebrate, fish, and algal specifies have been identified in the NWHI.  The magnitude of the problem of aquatic invasive species is far greater in main Hawaiian Islands than in NWHI. Endemism and diversity in the NWHI has reportedly been higher than the main Hawaiian Islands for some corals and other reef species. However, the Northwestern Hawaiian Islands have not been free from human influence.

Early influence of man can be traced back approximately 1,000 years ago when Polynesians were the first to change the natural ecosystems of the islands. They brought to the main Hawaiian Islands animals such as boars, dogs and rats. However, the first documented evidence of mammals being introduced to the NWHI occurred in 1894 when entrepreneurs from a rabbit canning industry released rabbits that literally devoured all the vegetation on some islands; Laysan, Lisianski, and Southeast Island at Pearl and Hermes Atoll. Other alien or exotic plant and insect species (those that have been brought from other areas) drastically changed the existing ecosystems by destroying or out-competing many of the native endemic species. Until very recently the exotic Polynesian rats were major predators on Kure Atoll; eating the bird eggs and killing chicks. Today all the NWHI are completely rat free.

An old Coast Guard anchor sits deep within the Verbesina, a bright yellow flowering plant in the sunflower family that is an exotic, invasive plant on many of the atolls.
An old Coast Guard anchor sits deep within the Verbesina, a bright yellow flowering plant in the sunflower family that is an exotic, invasive plant on many of the atolls.

The Verbesina encelioides that we viewed on Kure Atoll; a bright yellow flowering plant in the sunflower family, is an excellent example of an exotic, invasive plant. This weed has literally suffocated and killed native plants as well as engulfed open space used as  nesting sites. Without weeding efforts by researchers, scientists and volunteers the birds would no longer have “runways” to allow the fledgings to run, take-off, and try their wings. Approximately 312 plant species have been identified on the NWHI. Thirty-seven species are indigenous, 12 endemic, the other remaining 267 are alien or exotic species.

Of the 485 species of insects and spiders found in the Northwestern Hawaiian Islands over 300 of them have been introduced by accident. Only 100 out of 485 are indigenous and another 80 are endemic. It is estimated over 20 new species of insects are introduced accidentally to mainland Hawai`i every year. This is just one reason why strict regulations are in place to minimize the introduction of new species to the NWHI. Exotic insects have devastating effects on the natural ecosystems. Ants on Kure Atoll have plagued the seabird chicks, who are relatively immobile during their early years and stay in the same nest area. Ants also displace native insects and can have such a major influence on ecosystems that they invade, or are introduced to, that they are called “ecosystem busters.”

In addition to the biological invasions, man has also brought other contaminants to the Northwestern Hawaiian Islands. Even though the area is thousands of miles from human inhabitation the islands remain impacted by man’s past military occupation. Kure Atoll is still recuperating from the remains of a Coast Guard station, LORAN tower and unlined dump site on the island. Contaminants may include elevated levels of copper, nickel, lead and polychlorinated biphenyls (PCB’s). Midway contamination from military operations include; petroleum, DDT, PCB’s, and heavy metals such as cadmium, lead and mercury. Over 75 million dollars were allocated by the Department of Defense for extensive clean up efforts on Midway Atoll just prior to the Naval Air Facility’s transfer to the U.S. Fish and Wildlife Service.

The remoteness of the area does not protect the islands from the prevailing ocean currents and man's trash.
The remoteness of the area does not protect the islands from the prevailing ocean currents and man’s trash.

During the Navy’s tenure at Midway,  in an effort to protect their pilots and aircraft, they would permit the deaths of thousands of albatrosses which are large enough to cause a danger to aircraft during landing or takeoff. In the short period 1957-58, over 36,000 birds were slaughtered and unknown thousands in subsequent years in an attempt to keep a major runway clear of albatross on Sand Island. When dead albatrosses began piling up on Midway, the commanding officer ordered them dumped at sea. However, with poetic justice, the prevailing currents carried an entire barge’s contents of rotting bird carcasses back to the beach at Midway and sailors had to pick them up and bury them.In the late 1800’s and early 1900’s the Northwestern Hawaiian Islands were exploited and ravished by seal hunters, whalers, feather hunters, pearl divers and guano miners. Seals, sea turtles, seabirds, sharks and whales were slaughtered en mass. In 1824 the ship Gambiamay have taken as many as 1,500 seals. The ship’s log of the Ada (1882) reported taking 103 sea turtles in just three days. Japanese feather hunters slaughtered thousands of seabirds. In the period from 1904 to 1915 counts of 284,000, 64,000, 119,000 and 200,000 dead birds and literally tons of feathers, were confiscated from Japanese poachers. These numbers represent only a fraction of the slaughter; only those who were caught poaching; many hundreds of thousands of bird deaths went undocumented and undetected.

The black-lipped pearl oyster (Pinctada margarifera) is one of the most obvious examples of the devastation man’s exploitation may cause. Masses of oyster beds were discovered at Pearl and Hermes in 1927. Within only three years of discovery estimates of over 200,000 oysters or 150,000 tons had been harvested and the oysters almost eliminated. An act was passed in 1929 making it illegal to take pearl oysters in Hawaiian waters. Later, in 1930, an expedition was sent to determine the extent of the damage to the oyster beds; only 480 oysters were found. By 1950 only six oysters were observed, and in 1969 only one oyster was found. More recent surveys in 1969, 1996, and 2000 found only a few oysters while a comprehensive 2003 NOAA study documented sightings of over 1,000 individual oysters. However, while the latter study suggests the oyster population may be starting to recover, almost 80 years have passed and the numbers do not begin to compare to the pre-exploitation levels. The pearl oyster clearly demonstrates the damage a coral reef can sustain from over-harvesting and the inordinate length of time it may take to recover even under full protection.

Fortunately, the entire reef is partially protected from many human influences by location and strict State and Federal restrictions. Existing in such a remote location the atolls and islands do not have the typical issues of coastal pollution and eutrophication from human inhabitation, tourism, development or agriculture like the main Hawaiian Islands. For the most part, the only humans to visit this isolated wilderness are researchers and scientists and they must sign and adhere to strict government permits and quarantines. All clothing or soft goods must be frozen for 48 hours to help prevent alien insects or seeds from going ashore. All dive gear must be soaked in a bleach solution after each use. Many varieties of fresh fruits and vegetables are forbidden on the islands.

However, the remoteness of the area does not protect the islands from the prevailing ocean currents and man’s trash. Currents in the North Pacific carry plastics and marine discards to the island shores. A portion of this debris may be terrestrial in origin while much of it obviously originates from fishing ships. As we walked along the shores of Kure Atoll we observed thousands of articles of domestic or household origin and items that were clearly from marine origins such as floats, nets, and other equipment connected with the industry. Based on past and current marine removal operations it is estimated that over 1,000 tons of debris has accumulated in the NWHI. Yearly accumulation rates are estimated at 40-80 tons. These amounts will continue indefinitely unless we educate and reduce the sources.

Legally, acts have been passed since the early 1900’s in attempts to protect the fragile creatures of the NWHI. Earliest efforts by Teddy Roosevelt (1909) attempted to protect the seabirds from the feather hunters by establishing the Hawaiian Islands Reservation. This reservation granted protections from Nihoa to Kure Atoll (minus Midway Atoll which at the time was owned by the U.S. military).  Since sea turtles travel from the NWHI to feeding grounds throughout the main Hawaiian Islands full protection did not occur until 1973 with the Endangered Species Act. Wild dolphins are protected under the Marine Mammal Protection Act, while the Hawaiian Monk Seals are protected under both the Endangered Species Act and the Marine Mammal Protection Act. The NWHI are of critical importance to monk seals and the sea turtles. The majority of the monk seals in existence live in the NWHI. Over 90% of green sea turtles depend upon the French Frigate Shores for their breeding grounds.  Researchers take surveys and collect information on the life cycles of the animals in an attempt to aid recovery of the populations and ensure that any of these species will not become extinct. Data is collected on monk seals, spinner dolphins, seabirds, and turtles by researchers in the NWHI.

Most recently, President Bush changed the designation of the marine area from a coral reef ecosystem reserve to include the islands as a Marine National Monument to effect more immediate change. By doing this the eight fishing permits that currently exist for the area will be phased out in five years and the entire Northwestern Hawaiian Islands will fall under more stringent long term protection.

However, legislation and presidential actions will not stop the debris that is carried from thousands of miles by ocean currents and deposited on the shores of these islands or correct some of the more subtle impacts of man that remain. We need to look deeply into the past, reflect upon our trespasses, and learn from our mistakes. Only education, protection and careful scrutiny of our environment and natural resources will accomplish this and provide future protection. Prevention is a better solution than attempts to clean-up. History tells us we must be better care-takers of our fragile coral ecosystems.

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Patricia Greene, July 7, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: July 7, 2006

Science and Technology Log

The majority of the Hawaiian monk seals are found in the Northwestern Hawaiian Islands from Nihoa Island to Kure Atoll with a small number on the main Hawaiian Islands.  Traditionally Monk seals have been killed for food by early sailors.  The species was declared depleted under the Marine Mammal Protection Act in 1976 following a 50% decline in beach counts.  Monk seals were also classified as “endangered” under the Endangered Species act in 1976.  Undersized female pups from the French Frigate Shoals were rehabilitated and released on Kure from the 1980’s until 1995 in an attempt to re-establish populations.

Most pups are born between February and July with the peak in April and May.  The newly born pup is totally black and weighs approximately 20 to 30 lbs.  By the time they are weaned (30 to 40 days) they will increase their weight to over 100 lbs.  Monk seals in the Northwestern Hawaiian Islands tend to wean their pups sooner at approximately 30 days, while seals on the Hawaiian Islands tend to nurse longer; as many as 60 days. Northwestern Hawaiian Island pups tend to be smaller in size as a result.  Females give birth on beaches with shallow water to protect their pups from sharks.  A female will not give birth until they reach five to ten years of age.  By the time the researchers arrive on Green Island most female seals will have already pupped.Approximately 90% of the monk seals remain at the island where they were born for life.  During our recent visit to Green Island, I interviewed monk seal researchers Tracy Wurth and Antonette Gutierrez from the National Marine Fisheries Service.  Tracy and Antonette have been in the field on Green Island since May 16, 2006 collecting data on the monk seal population.

Field researchers from the National Marine Fisheries Service on all the Northwestern Hawaiian Islands keep careful track of each seal in the colony; identifying individuals with applied tags and bleach marks as well as natural markings or scars.  Every seal is photographed by taking photos of all sides and flippers and are documented in a digital photo library.  New pups are tagged as soon as they are weaned at 30 to 40 days.  Plastic “temple” tags are applied to each rear flipper and injected with a micro-chip pit tag.  Flipper tags are color specific to each island; Kure uses grey tags, while Pearl and Hermes uses light blue tags.  The letter assigned will tell researchers what year the pup was born.  One pup with a bleach mark “Z26” swam close enough to our boat for us to read his marks.  Later the researchers knew exactly what seal we had seen and told us it was a “weaner;” a pup born is this year that had already weaned.Tracy and Antonette conduct seal patrols on Green Island on a daily basis.  They walk the beach collecting information on each seal observed.  Approximately every fourth day they conduct an atoll count, which is a standardized seal patrol that is time sensitive and basically captures a “snapshot” of the population at a given time.  For their atoll counts the seal team start their survey on Green Island at 1:00 pm and when finished take their boat to Sand islet and conduct a survey there.  Atoll counts take the researchers approximately three hours.

Researchers also collect marine debris such as nets on shore or in shallow water and move it to a secure location to be picked up at a later date by the National Marine Fisheries Coral Reef Ecosystem Division.  The collection of marine debris is extremely important because monk seals can become entangled in the nets.During the field season information is collected on injuries, wounds, illnesses, abnormalities, as well as deaths/disappearances, births, and any unusual events.  If a dead seal is found a necropsy is performed and samples from organs and tissues are collected.  Researchers also collect specimens of scat and spew (vomitus) in an effort to analyze the monk seal’s diet.  Tissue plugs are taken from tagged pups for DNA analysis to determine maternity.  Priorities for the Kure researchers include all of the above, while male aggression and shark predation mitigation is not a significant problem here at Kure Atoll.  However, researchers are concerned about the future seal population due to low juvenile survival.  As the current breeding females get older or die there will not be younger seals to take their place in the breeding population.

At Kure Atoll, the adult seal population in 2005 was 86 individuals with 23 pups born.  The population at Kure has been slowly decreasing over the last several years.  One major factor is the low juvenile survival rate due to lack of nutrients and resulting emaciation.  However, this year their numbers show an increase in juvenile survival with a re-sight rate of over 60 percent.  In the past the re-sight rate has been closer to only 30 percent.

While on Kure Atoll, the researchers enter their data in the field database system. When the researchers return from their assignment they will file their final report.  This information will be summarized in published papers and used by various institutions such as the Hawaiian Monk Seal Recovery Team.

The future of the protected monk seal is unclear. Today, researchers estimate the total monk seal population in existence is approximately 1,300 to 1,600 seals. Researchers are concerned if the population continues to decline the total number could fall below 1,000 within the next five years. Scientists and researchers work together to find solutions to aid the recovery of the Hawaiian monk seal.

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Patricia Greene, July 6, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: July 6, 2006

Science and Technology Log

We arrived on Green Island at Kure Atoll and observed thousands of Laysan Albatross, (Phoebastria immutabilis),chicks and fledglings.  As we walked the island we noted dead birds among the living.  To some extent this may be a natural occurrence.  Only one egg is laid and both parents nurture the chick.  In the early stages the parents return often with frequent feedings.  As the chick matures and becomes older the feedings become less frequent; at this age perhaps just once a week.  The parents may travel hundreds, even thousands of miles across the Pacific Ocean far as the Aleutian Islands to forage.  Meanwhile, the chicks wait close to their hatching spot for a parent to return.

In a perfect world untainted by man, our chick’s diet would consist of fish and fish eggs, squid, and octopus.  Yet in our world and the “age of plastics” the chick will likely be fed some amazing indigestible, synthetic products. The parent albatross has a perilous journey.  On the way one or both of parents may fall victim to long line fishing or nets, power lines, planes, sharks or other predators.  If one parent is killed, the other parent will probably not be able to provide enough food to sustain the chick; the chick will sit and wait for the parents; eventually starve to death, or if it is old enough and ready, it may try its wings and fledge.

Although a chick may be fed plastics, once they reach fledgling age they are usually able to regurgitate the indigestible material and cleanse their bodies of the plastic.  However, if the pieces are too large or in this case, large, sharp and piercing, the bird may die an agonizing death; totally impacted and/or the lining punctured.  As we walked the paths of Green Island we observed many young dead albatross.  After viewing this incredible necropsy we contemplate how many of these young birds may have met a similar fate to the one we necropsied.  Our specimen was chosen at random, selected only because we realized it had died within the last few hours.On July 1, 2006, Cynthia Vanderlip conducted a necropsy of a chick that had expired a few hours previous.  The “chick” had a wing spread of 5 to 6 feet and weighed approximately 5 lbs.  The contents of the bird’s stomach amazed and shocked the teachers and scientists.  The dead chick was severely impacted and literally full of plastics.  Some pieces were approximately 6 inches long and several were sharp and jagged.  We could conclusively state this bird was killed by the plastic debris because of the observed puncture in the lining of the proventriculus.  We removed the plastic from our bird and counted an excess of 306 pieces of plastic!

Typically, Laysan Albatrosses have a larger volume of ingested plastic than any other seabird because their favored food, flying fish eggs, are attached to floating debris, and in our modern world most of this debris is plastics, where it used to be wood or pumice.  Floating is one of the properties of plastics.  The most recent research that we had available to us on the island regarding plastics and albatross chicks was published in 1995.  According to this research by Auman, Ludwig, Geis, and Colburn: “ingested plastic probably does not cause a significant direct mortality in Laysan Albatross chicks, but likely causes physiological stress as a result of satiation and mechanical blockage.  Resulting problems may include; starvation, suppressed appetite, reduced growth rate, lower fledgling masses, obstruction of the gut, and decreased fat deposition.”

Interestingly, much of the plastic found in the Northwestern Hawaiian Islands is of Japanese origin.  As we walked the beach we observed many plastic articles with Japanese writing on them.  In the boli from chicks we observed Japanese cigarette lighters and in our specimen there was a piece of plastic with Japanese writing on it.  Some of the debris may be from Japanese fishing boats or perhaps from the warm Kuroshiro current that flows from Japan.Research suggests there is an upward trend in the volume and mass of plastics found in the Laysan Albatross chicks.  In 1966, 74% of 91 chicks contained some plastic, with 8 pieces being the greatest number found and the average mass only 1.87 grams.  In the 1994/1995 study 18.1 grams and 23.8 grams respectively.  From our recent experience, we could only imagine what the numbers look like now in 2006.

In a few days, our bird will be gone; devoured by the decomposers and scavengers.  At night the ghost crabs will come out of their burrows and feast on him; beetles and fly larvae will clean up the remains.  Soon the bird will be reduced to just a pile of feathers but the plastics we found will remain for years.Another concern is when the albatross eats burned or melted plastic parts.  These are especially toxic because of release of organochlorines; polychlorinated biphenyls (PCB’s) and phospholipid foams, which can be absorbed and harmful to both the adult birds and their chicks.  Many pieces of burnt plastics were observed on the island and in the chick Cynthia conducted a necropsy on.

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Patricia Greene, June 28, 2006

NOAA Teacher at Sea
Patricia Greene
Onboard NOAA Ship Hi’ialakai
June 26 – July 30, 2006

Mission: Ecosystem Survey
Geographical Area: Central Pacific Ocean, Hawaii
Date: June 28, 2006

Science and Technology Log

We awoke with anticipation at approximately 5:30 a.m.  Today we were scheduled to arrive at Kure Atoll and with any luck would have our first snorkel experience in the Northwestern Hawaiian Islands.  We have been in transit twenty-four hours a day for six days onboard the NOAA Ship Hi’ialakai.  We have covered a distance equal to traveling from Houston, Texas to Reno, Nevada.

Our snorkel gear is placed on deck near the loading area at 6:45 a.m. and after a quick breakfast we go up on deck with anticipation of our first view of Kure’s Green Island.  Two shade trees are in the middle of the island and appropriately a rainbow drapes the north end.  Birds; albatrosses, terns, and frigate birds fly out to greet us, while spinner dolphins play in the spray at the bow of our ship.  What an awesome welcome!

At last we are instructed to load and we pull away from the Hi’ialakai, excited and anxious to see this underwater realm that we have all been reading, researching and immersed in the last six days while transiting.At 7:30 a.m. the dive and snorkel team meet on the fantail and receive one last safety meeting from the Chief Boatswain and Dive Saftey Officer, Mark L. O’Conner.  Protocol on the ship is that the Maritime Archeology dive boat, the H1, is loaded first with supplies and people then lowered by crane into the ocean.  Next the research vessel Ahiwith the University of Hawaii and NOAA mapping crew will enter the water, also by hydraulics.  Lastly our snorkeling boat, an inflatable zodiac with a 50hp 4 stroke will be placed in the water.  The only difference is our boat is not loaded so therefore we pass supplies into the boat and then we will need to climb down a Jacob’s ladder on the side of the Hi’ialakai in order to enter the boat.

Our first reward is the sight of a Hawaiian monk seal on one of the sand spits.  Ordinary Seaman, Jason Kehn, our coxswain, is careful to take the boat far around the area so as to not disturb this rare, endangered species.  The monk seal is apparently oblivious to our presence and only when we see a flipper move and his head rise, are we sure he is not dead.

After last minute safety instructions and advice to “look predators in the eye,” we are ready to enter the reefs.  The water around us is a collage of vibrant shades of blue and turquoise.  We open our eyes and are surrounded immediately by a huge school of chubs; seemingly curious and unafraid of us.  The visibility is phenomenal, probably 80ft.; the water crystal clear with no turbidity.Jason competently maneuvers to our dive site; we are grateful that he knows the area because our GPS is telling us we are still 21 miles from the site! We tie up to a CREWS (Coral Reef Early Warning System) buoy; one that transmits temperature, turbidity, and other environmental data that can detect significant impacts to the coral reef ecosystem.

Fishes are numerous in Kure Atoll’s lagoon. Smaller species dominated our survey area. This may be explained by the coral reef habitat.  Coral cover was around 80 percent, with finger coral (Porites compressa) being the dominant species.  Living finger coral provides many hiding holes for the juveniles and adults of smaller species, and this may be the reason for the great abundance of smaller species of fish.

Ellyn, our naturalist from Hawai`i, observed that overall there is greater diversity in the fish species in the NWHI than on the main Hawaiian Islands, however, in general the fish were smaller in size for their species.  Patty, our Teacher-at-Sea from the Florida Keys noted that overall the coral appeared much healthier that many of the reefs in the keys and noted the absence of the soft corals and brain coral so common in the keys. Finger coral may be an endemic species and is quick growing, often out competing other coral species for space.  Massive continuous heads created yards of living reef on our survey site.  We observed that the sheer weight of the massive heads often forced large pieces of living reef to break off and form rubble fields below the living reef.  These rubble fields provide highly desirable substrate onto which other species of corals recruit and create many tiny hiding holes, very desirable homes for larval fish to recruit into from the water column.  Homes for the adults, homes for the recruiting juveniles…what a perfect place to live!