An interesting Hawaiian Monk Seal article you might want to read:
http://www.hanahou.com/pages/magazine.asp?Action=DrawArticle&ArticleID=740&MagazineID=46
AS TAKEN FROM HAWAIIAN AIR'S HANA HOU In Flight Magazine:
On a recent Sunday, I was surprised to see a strange object moving toward the shore at Queen’s beach on the eastern end of Waikïkï. It was the pointy head of a Hawaiian monk seal, a creature that was once so rare in the main Hawaiian Islands that the first recorded sighting dates from 1928.
There were a dozen people in the water between the seal and the beach, so it turned, swam around a jetty and landed on an even more crowded beach. About fifty people gathered as the glistening black animal—7 feet long and weighing 500 pounds, I would later learn—hauled out on the beach, its blubber rolling in waves across its body as it climbed the slope (unlike sea lions,seals don’t use their fins to walk on land; they move like caterpillars). Its dark, soulful eyes surveyed a solid wall of camera-wielding spectators not 20 feet away. The crowd ignored a man urging them to step back and give the seal space. When another man got within 6 feet of the seal’s head for a closeup, it rolled languorously back into thewater and swam away.
A scene like that would have made headlines only fifteen years ago, but today, following a remarkable change in the seals’ behavior, it has become commonplace, to the delight of biologists and tourists alike.
Few animals are as studied as the Hawaiian monk seal, which became the official state mammal this year (not to be confused with the official state marine mammal, the humpback whale). More than 500 volunteers around the Islands and some two dozen state and federal officials are involved in counting, observing, protecting and, when they die, performing autopsies on them. There are tissue samples for nearly every individual seal that has lived in the last ten years. DNA from those samples tells scientists which seal is related to which, and how.
And yet the monk seal remains one of the animal kingdom’s biggest puzzles.
Typically, marine mammals thrive in pristine environments. The Northwestern Hawaiian Islands (NWHI) have been mostly undisturbed since the late 1950s, when the first count was made. Yet the monk seal population there has been dropping at an average rate of 4 percent since then. In the midst of abundance—the estimated weight of all fish in the NWHI averages 2,000 pounds per acre—the females are thin. They are unable to provide enough milk to their pups; the pups have too little fat to sustain them while they learn to find food and avoid predators. Most starve or are eaten by sharks.
Conversely, marine mammals usually fare poorly in environments like the main Hawaiian Islands, where their food—fish, octopus and lobster in the seal’s case—is growing scarce. Today, after decades of overfishing, the average fish concentration in the main Hawaiian Islands is 600 pounds of fish per acre, less than a third what it is in the NWHI. Yet the monk seals have prospered here, growing from single digits to more than 100 in a decade. The females observed in the main islands are fat and sleek, and when the pups wean, they too are bursting with health— even near overcrowded, overfished O‘ahu, where the average density is 250 pounds of fish per acre. These days, a dozen pups are born every year, and nearly all survive: an average yearly increase of 8 percent. The animals here are “absolutely massive” compared with those in the NWHI, says Charles Littnan, chief scientist for monk seals at NOAA, the National Oceanic and Atmospheric Administration.
Scientists are not just surprised; for now, they’re stumped.
The monk seal is a living fossil, the oldest of all seals, unchanged for 15 million years. It is believed to have evolved in the North Atlantic and spread to the Mediterranean (where only 400 remain today), then to the Caribbean, where it is extinct. It arrived in Hawai‘i some 10 million years ago and since evolved into a different species. That species remains endemic—unique—to Hawai‘i.
By the time the first Polynesians arrived in Hawai‘i ten to fifteen centuries ago, scientists believe the seal population was centered in the main Hawaiian Islands, which offer 940 miles of coastline and plenty of reefs. Given the abundance of food and shelter, that population may have been quite large.
But there is no mention of seals in Hawaiian mythology, nor are there any surviving artifacts made of seal bone, so scientists conjecture that the first Polynesians killed off most of the seals and drove away the rest to the less hospitable northwestern islands. There being no land mammals, let alone predators in Hawai‘i at the time, the seals would have used the beaches as safe areas to rest, sleep and pup; they apparently did not have time to evolve a defense against humans, allowing themselves to be clubbed to death with ease.
With the arrival of European and Japanese ships centuries later, the NWHI were no longer a safe haven for the seals, which became targets for sealers who sold the oil and the skins. They were also killed for food by guano miners, albatross feather collectors and shipwrecked sailors. By 1889, a ship’s crew stranded on Midway Atoll for fourteen months saw not one seal, nor did a team of surveyors in Laysan Island in 1891, nor a group of biologists who were there for six weeks in 1911. But enough seals survived the massacre to keep the species going so that in 1956 a beach count in the NWHI spotted 916 adults, which means there were probably some 4,000 seals—the rest being at sea at the time of the count.
Since then the trend has been steadily downward. In 1976, the species was officially listed as endangered, and a cottage industry to study it and stop its decline was born.
Bill Gilmartin led the first NOAA team in 1981. “My job was to monitor, but I saw that there were a number of problems that we could do something about,” he says. In Kure atoll, his team captured thirty-two underweight female pups. They fed and released them in much better shape after a few months. Another 100 female pups were taken from French Frigate Shoals, where the seals were declining, to O‘ahu, where they were fattened with herring and released at Kure. When Laysan had an excess of males whose crowding during mating killed up to a dozen females a year, thirty-six males were removed to restore balance. Some of the pup-eating sharks were culled.
Still, after numerous scientific papers and nearly $30 million spent, the number of seals in the NWHI continued to drop. Worse, the decline accelerated from an average of 4 percent over the past decade to 6 percent last year. Using the same survey methods that counted 916 seals in 1956, the latest count in 2002 found only 293, suggesting a population of some 1,200. Clearly, the conservation efforts were failing. While it’s understood that the decline is the result of pup mortality, no one knows for sure why the pups are dying, says Littnan.
Meanwhile, in the main Hawaiian Islands, a handful of females—as few as five—started trickling in during the late 1980s, and 1996 saw the first recorded births on O‘ahu and Moloka‘i. At least eighty-six more have been born since.
As the seal population in the main Islands has grown, theories have begun to emerge.
While there are more fish in the NWHI, posits Alan Friedlander, a coral reef ecologist with NOAA’s biogeography branch in Honolulu, it’s the type of fish that makes the difference. “In the main Hawaiian Islands there’s only a third of total fish mass that there is in the northwestern ones. But if you take out the big jacks and sharks, which compete with seals for food, and you look only at the smaller fish, there is not that much difference.”
Second, says Thea Johanos-Kam, a monk seal biologist, critter-cams and electronic recording tags have shown that seals primarily feed on the outer slopes of islands, mostly at depths of 150 to 350 feet, where fish populations have been much less affected by fishermen than in shallower waters. Also, the seals eat eels, wrasses and other fish not taken by man. “The potential for competition between foraging monk seal and fishermen may be lower than it may seem,” she says. The theories seem plausible, but until further research is conducted, the reappearance of monk seals in the main Islands remains a mystery.
Whatever the reasons, though, there’s cause for cautious optimism. “Given the current rates of growth in the main Islands and the decline in the Northwestern Islands,” says Friedlander, “the two populations should even out at 400 seals each in a little less than 20 years.”
As a result of the unexpected return of the monk seal to its ancestral home, we have learned a great deal more about its behavior. Most seals and sea lions congregate in large numbers, so analyzing their individual behavior is difficult. Not so for monk seals, which tend to be loners, says D.B. Dunlap, a retired fireman who observes the monk seals on Manana, an islet off O‘ahu’s windward coast also known as Rabbit Island. Dunlap has spent most of his time since 2001 observing the seals on Manana’s small beach through a telescope from the Makai Research Pier in Waimanalo.
Dunlap knows every seal by name or number; he has produced a wealth of data on their behavior that might be unequaled for any other type of seal. I met Dunlap at his observation perch two weeks after I saw the seal on that crowded Waikïkï beach; he’d already heard about it. “That was Kermit,” he said. “He’s the No. 1 admirer of Irma.” Irma is a mother of five he first \ sighted on Irma’s Beach in 2001. “I see Irma with other males, and I see Kermit with other females, but most of the time if they’re not alone, they’re with each other,” says Dunlap. “That’s interesting because there are no known life-pairings of monk seals.” As for my sighting, Dunlap says that Kermit and Irma are five seals among O‘ahu’s population of about thirty-five who show no fear of people and regularly bask on crowded beaches, usually while traveling from one coast to another. “I bet he was just looking for Irma and wouldn’t have stayed anyway,” says Dunlap.
Aside from crowds getting too close, which can stress the seals, they face another threat on O‘ahu: gill nets, floating curtains of nylon monofilament that have already snagged and drowned three seals in the main Hawaiian Islands, two in the last two years.
The deaths could mean that local fishermenand the monk seal are on a collisioncourse, says Paul Achitoff of Earth Justice: “If gill nets can’t be used without killing monk seals, then the state’s regulation of the nets makes it vulnerable to a suit under the Endangered Species Act, and it’s very possible the federal court would ban the nets.”
One of the gill-net victims got entangled just off the Makai Pier, not 100 yards from the spot from which Dunlap watches the beach on Manana, where up to nine seals might haul out at once. “People are still putting out gill nets in the same place,” he says. “It’s bound to happen again.”
David Schofield, the marine mammal response coordinator for NOAA, is more optimistic. “We’ve made enormous progress in sensitizing people to the needs of the monk seal,” he says. Though if Kermit’s experience at Waikïkï Beach is any measure, monk seal advocates have their work cut out for them in educating visitors and residents alike about giving these animals some room. Still, says Gilmartin, who headed NOAA’s first recovery effort, “It’s going to be up to all of us to learn to share our space here with monk seals if the species is going to survive.” HH
State and federal law prohibits harassing monk seals. Try to stay 150 feet away from seals if at all possible. Keep dogs leashed and away to avoid injury and the spread of disease.
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