American Samoa National Park Nature Page
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American Samoa National Park Nature Information
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Giant Clams (faisua) by P. Craig, NPS
Giant clams (faisua) are magnificent animals and it's always a pleasure to see one of these beauties on the reef. They are large, colorful and, surprisingly, the clams are part animal and part “plant”. That's because giant clams, like corals, have plant-like cells (zooxanthellae) in their tissues that produce free food for the clams. When a clam opens its shell and spreads out its pretty mantle, it exposes these solar panels (the zooxanthellae) to the sun to make food, like a plant unfolding its leaves.
At the same time, the clam also gets some food by drawing water through its siphon and filtering out any tiny food particles (zooplankton). Perhaps that's why giant clams grow so large – they have two very different ways to get food.
We have two native species of giant clams in our local waters, Tridacna maxima and T. squamosa, which look fairly similar. They grow to about 12-15 inches in shell length, although most found today are much smaller because the larger ones have been over-harvested. The largest and most famous species of giant clam (T. gigas), which grows as big as a large suitcase, does not occur in our waters.
Because giant clams need sunlight, they inhabit shallow, clear waters down to about 60 feet deep. They grow very slowly; one local clam was 18 years old. They spawn repeatedly over their life span and release millions of eggs each time they spawn, but most young clams do not survive, so the adults have to live a long time and spawn many times to insure that the population survives. Larval clams swim in the water for about a week, then settle permanently onto the reef to grow.
The clams are a favorite food item throughout the South Pacific and their accessibility in shallow waters and slow growth make them susceptible to overfishing. That is very much the case in American Samoa, where few remain on many of our reefs. There is a growing concern that our population of giant clams may be getting too few and far between to spawn successfully.
Partly for that reason, there has been an interest in growing these clams in hatcheries to supply markets for food and the aquarium trade. DMWR has operated a hatchery here for many years and tried to encourage local production by supplying small clams for local 'farmers' to grow them on their reefs. That effort has met with limited success for several reasons. Considerable dedication is needed because it may take years to grow the clams to a commercial size, and the clams have to be protected from poachers and predators. And there are always fa'alavelave events that call for contributions of giant clams if anyone has some. In general, giant clam mariculture here has usually supplemented family needs rather than create a commercial business.
Harvest regulations in American Samoa are: giant clams taken for personal consumption must be at least 6 inches in shell length, or if sold, a license is required and giant clams must be at least 7 inches in shell length and sold with the clam still in its shell.
Snakes In Samoa by P. Craig, NPS
Snakes in Samoa? You bet. Two kinds, one right here on Tutuila Island and the other on Ta'u Island. Fortunately, neither is the dreaded brown tree snake (more about that below). Also fortunately, neither is poisonous, both mind their own business, and they are no threat to anyone.
On Tutuila, we have an unusually small black snake that looks like a plump earthworm about 6 inches long. A closer inspection reveals that it has tiny scales. It's called the potted soil snake or blind burrowing snake (Typhlops braminus), because it has almost no eyes and it burrows through the soil. This secretive nocturnal snake is occasionally found by someone digging in their garden. It eats small soil creatures like termites and insect larvae.
This harmless snake is widely distributed around the world, but it is not a native species of our island. It was probably introduced here when its eggs were carried in the soil attached to some imported plants or machinery. In 1993, it was found in the Tafuna area. Another one was found in Pago Pago in 2001.
The other snake found on Ta'u Island is the gata or Pacific boa (Candoia bibroni). It also occurs in western Samoa. At one time it inhabited Tutuila Island (its bones were found there) but went extinct for unknown reasons. The Pacific boa is more commonly found on islands closer to Indonesia; American Samoa appears to be the eastward limit of its distribution.
This snake grows to a respectable length of 3 to 6 feet. It tends to be tan or darkly colored, but its coloration can be variable. This species is usually found in forests, it is active mainly at night, and it probably eats lizards, rats, and small birds and bird eggs.
The Pacific boa looks a lot like another undesirable snake species, the brown tree snake (Boiga irregularis), which we don't have in Samoa and hopefully never will. You may have heard that the brown tree snake invaded Guam and caused havoc there. It wiped out Guam's native bird species and helped decimate their fruit bat populations by eating the young bats left hanging in the trees when the adults flew off to find food.
Parents in Guam were even advised to keep their infants and small children away from this snake because it is somewhat poisonous and occasionally has been caught lunching on a baby's arm. How's that for a reptilian nightmare?
Well, not to fear. We do not have the brown tree snake in Samoa. So, if you see a large snake on Ta'u island, don't kill it. However, if you see one on Tutuila Island, it is very important that you send it to DMWR for identification. It is essential that we keep the brown tree snake out of American Samoa. Several of them have already slipped into Hawaii hidden in aircargo shipments from Guam. The snakes will crawl into the cargo or onto the plane's landing gear and then go wherever the plane goes.
A final note. On rare occasions, sea snakes have been seen in our coastal waters. One verified air-breathing banded sea snake (probably Laticauda columbrina) was collected here in 2000. However, most local sightings of 'sea snakes' are actually fish (eels) that are very snake-like in appearance. It would not be difficult to confuse the two:
Toads Everywhere by Gilbert S. Grant, DMWR
The marine toad (Bufo marinus) is a recent introduction to American Samoa. It was purposely brought here in 1953 to control mosquitoes or insect pests that attack taro.
The toads (lage) were brought from Hawaii and introduced into artificial ponds at Taputimu on Tutuila. From there, stocks were liberated in Tafuna and Utulei. The toads then expanded their range to include all of Tutuila, from sea level to the top of Mt. Alava. Fortunately, they have not yet been transported to Manu'a or to western Samoa.
The toads breed year-round here. All they need is standing fresh or slightly brackish water in which to lay their eggs. Thousands of eggs that look like a string of black and white pearls are laid by each female. Within a week the eggs hatch into small black tadpoles that feed voraciously on aquatic plants. The tadpoles look defenseless but are thought to be toxic to birds and other animals. Within a month these tadpoles develop legs and change into adult toads.
As adults, they typically hide under boards or vegetation during the heat of the day and emerge at night to feed on insects and other invertebrates. They eat snails, millipedes, centipedes, spiders, roaches, moths, flies, caterpillars, termites, beetles, ants, earthworms, grasses, and even an occasional small toad.
How many toads inhabit Tutuila Island and how many bugs do they consume each night? In a wildlife study conducted in 1976, biologists estimated that over 2 million toads lived here with us. Some rough calculations suggest that these toads consume about 5 tons of bugs every night!
To some people it might appear that the toad is beneficial. One must keep in mind, however, that many of those insects would have been eaten by native birds and perhaps by the small insect-eating sheath-tailed bat (pe'ape'avai) that is now extremely rare in American Samoa. No one has examined the actual impacts the toads are having on our native wildlife, but there are many examples of introduced species causing the extinction of native plants and animals by out-competing them for food or other resources.
Another concern involving the toad is its toxic skin glands. The adults have two large parotid glands on their “shoulders” that secrete a creamy white fluid when handled. These secretions are highly toxic if eaten, rubbed into the eyes, or brought into contact with mucus membranes. Dogs have died when they mouthed these toads. In addition, a high incidence of the salmonella bacteria occurs in toads, thus an abundance of toads near drinking water supplies may lead to bacterial contamination.
Sharks by P. Craig, NPS
We are quite fortunate not to have much of a “shark problem” in American Samoa. Based on conversations with long-time residents here, it appears that there have been very few shark attacks in the Territory and probably no fatalities here in the past 30 years.
The few injuries that have occurred were usually related to fishing activities, and records from the hospital's Emergency Medical Services concur with this. EMS has responded to only one or two shark incidents in recent memory – one was a somewhat humorous account of two fishermen trying to land a shark in their boat. The first fisherman brought the shark up to the side of the boat so that his partner could club it, but his partner missed. The shark then reared up and bit the first fisherman, who then got mad and clubbed his partner for missing the shark.
The sharks (malie) living in our nearshore waters are generally not dangerous to swimmers or divers. The most commonly seen species are the blacktip reef shark (Carcharhinus melanopterus) and the whitetip reef shark (Triaenodon obesus). These are not large sharks, usually about 4-5 feet in length, although everyone swears that the one they saw was bigger. They feed on fish and shellfish. The whitetip has an unusual habit of resting occasionally on the seafloor during the daytime.
These two shark species are usually not aggressive but they may swim close by to see who's in their area. But both are attracted to wounded and bleeding fish, which accounts for several shark encounters with divers who had tied speared fish around their waists. Need it be suggested that this is not a smart thing to do?
The blacktip is easily frightened away, but on rare occasions small blacktips will sometimes startle a person by swimming directly at them. They look like a little torpedo coming straight at you, but other than your brief panic attack, no harm is done. Another quirk of the adult blacktip is that, at night, it may charge at a diver's light if the light shines on them for too long.
Sightings of more dangerous sharks in our nearshore waters are rare, but over the years, a few tiger sharks have been seen or caught around Tutuila. Also, hammerhead sharks are known to swim into Pago Pago Harbor, where some give birth to young and others are perhaps attracted there by the cannery wastes.
So, yes indeed we have sharks in our shoreline waters, but most are not of serious concern. Yet, someplace deep in our brain yells Danger! whenever we see one. But it is still very exciting to see a shark swim by. Our heart rate jumps, but then the shark is quickly gone, and our only thought is wow, did you see that?
The Alogo Surgeonfish - Ruler of the Reeftop by P. Craig, NPS
American Samoa's coral reefs are truly a wonder of nature. Our sea is home to a very diverse and colorful assemblage of plants and animals. Some 890 species of fish occur here, which is about twice the number of fish species found in Hawaii.
At first glance, the reef seems to be an exotic panorama of mass confusion, complete with bizarre shapes of fish painted in psychedelic colors. It's like looking into an overstocked aquarium. But as you frequent the reef more often, you begin to notice some structure to the confusion. Each species, for example, is generally found only in certain habitats such as shallow reef flats, sandy bottom areas, or deeper waters.
Many individual fish even take up permanent residence at a particular site rather than roam around. One particular fish I watched stayed at the same coral block for 3 years (it had a unique markings on its body, so I could easily identify it). That coral block was home.
Such stay-at-home behavior is actually quite common among coral reef fishes. One abundant species on our reefs that does this is the alogo, also known as the blue-lined surgeonfish (Acanthurus lineatus) because of its knife-like blade located near its tail. The blade is usually not visible because it is folded away into a groove in the fish's skin. It is a bit poisonous, and careless handling of the fish may cause a puncture and painful swelling in your hand.
The alogo grows about 8 inches long and weighs half a pound. It is a very attractive fish, with bold yellow, blue, and black horizontal lines on its sides, although its basic color pattern can be swiftly altered depending on the alogo's mood. For example, when the alogo becomes aggressive and chases another fish, its face and fins darken and it looks angry (to me at least).
The alogo lives in the foamy surge zone where the waves crash against the reef. This is not an easy place to live, but the alogo is adept at it. When a really rough wave hits, the alogo darts down into a hole or over the reef edge into the safety of deeper water.
Like a lot of other reef fish, the alogo is a territorial animal, which means that it dwells at a particular patch of reef and protects that site from all other fish. The territory of each alogo measures about 5 x 5 feet. There it feeds on the thin film of plant material (algae) that covers the reeftop and appears as a greenish grassy turf. Because of their territorial nature, the alogo space themselves evenly across the reeftop, and as they munch away on the algae-covered rocks, they remind me of a herd of miniature cows feeding in a distant pasture.
Many other species of coral reef fish are also algae eaters, and two general patterns of feeding have evolved among these species. One is for a species to become territorial and fiercely guard its own algal patch, the other is to be non-territorial and roam around the reef looking for an unguarded patch of algae to eat. To an underwater observer, this dual approach to feeding is readily visible, most of the reef is picked clean of all edible algae and looks like bare rock, except where a territorial fish guards its lush algal plot.
The feisty alogo defends its plot from all competitors, so the turf algae grows well there and provides all the food the alogo needs. Protection of this garden doesn't come cheaply, however. The alogo must defend its territory every minute of the day from other fish that lurk nearby, waiting for a chance to sneak in and eat the alogo's garden.
That's where the alogo's sharp blade comes in handy. The alogo will threaten to viciously sideswipe an intruder with this weapon. Most other fish heed the alogo's warning and back-off quickly. It's mostly a bluffing game played repeatedly through the day.
Other aspects of the alogo's behavior are fascinating. Every evening at dusk, all the alogo migrate off the reeftop to deeper waters where they will spend the night sleeping in crevices to escape being eaten by predators like sharks (malie) and jacks (malauli, ulua). At dawn, they return by the same route. Their migrations to and from the reeftop look like rush-hour traffic on an underwater highway.
The alogo is a popular Samoan food fish and it is the singlemost important species of reef fish caught, accounting for about 30% (by weight) of all reef fish caught in the nearshore subsistence fishery. Most are caught by spear fishermen, particularly at night when the fish are sleeping in reef crevices. Daytime spear fishermen have a much harder time catching them, because the alogo tend to stay just out of spearing range.
Manini and Pone - Two Favorite Reef Fish by P. Craig, NPS
Manini and pone are two favorite food fishes found just about everywhere in shallow waters around the islands of American Samoa. Like alogo, they belong to the family of fishes called surgeonfish because of their sharp knife blades that fit into grooves near their tail. Manini and pone are rather meek fishes, however, and they do not seem to wield their weapons much.
The manini (Acanthurus triostegus) is a small fish about 5 inches long. Its coloration is yellow with vertical black bars, which looks a bit like a prisoner's uniform and that's why this fish is also called the convict tang.
Manini often swim in large schools containing hundreds or thousands of individuals. There are two good reasons for this schooling behavior, it helps them escape predators and it also helps them get access to food. First, when a large fish attacks a school of manini, the manini scatter in all directions like a shotgun blast. This commotion momentarily confuses the predator and the manini get away. Each manini thus has a better chance of not getting eaten if it stays in a group.
The manini also cleverly use their schooling behavior to get food. They like to feed on the thin green algae turf that grows on reef rocks, but these algae patches are usually guarded fiercely by alogo surgeonfish and damselfishes (tu'u'u) who are nasty to intruders.
Just the sight of a manini gets them livid with rage. A single manini would not stand a chance to get by these guards, but a large group of manini can succeed. The alogo and damselfishes are simply overwhelmed when hundreds of manini descend into their protected territory to feed. While the alogo futilely chases one manini away, a hundred others are gobbling up its garden.
Manini spawning is a spectacular event. When conditions are right, thousands will assemble to spawn at a particular time and place. They often spawn in or near the reef channel (ava) at dusk when the tide is high. Their behavior and coloration is noticeably different at this time, as they swim around in a agitated fashion and change color to white with wider black bars.
This seething mass of fish mills about until they can't take the excitement any longer. A group of them will suddenly burst upwards in the water column, spawn, and return to the seafloor again, all in a split second. Although this happens fast, you can tell that the fish actually spawned because the milt expelled by the male fish looks like a puff of smoke from a gun. When the spawning action really gets going, it looks like an underwater version of popcorn popping.
After spawning, the fertilized eggs drift away with the currents. About 1-3 months later, the small manini that survived this larval stage are ready to settle back onto the reef.
Pone (Ctenochaetus striatus, or the lined bristletooth surgeonfish) are a different type of surgeonfish in two respects. They are a dull brown color and they have funny teeth. Their lack of spectacular coloration is somewhat of an embarrassment in tropical waters which are renown for brightly colored fish. Pone are, however, one of the most abundant fishes on the reefs, so they must be doing something right.
Their teeth have evolved very differently from other surgeonfishes because what they feed upon is quite different. Instead of having actual teeth to bite off algae the way that alogo and manini do, pone have a mouthful of bristles which they use as a comb or brush to collect the sediment and detritus that lies on reef surfaces. The detritus they eat includes all the small bits and pieces of formerly living plants and animals. The detritus in your backyard, for example, might include grass clippings, old ulu leaves, decaying coconut husks, rotting papayas, and numerous unseen dead insects.
Detritus is found everywhere, but few large animals can make a meal out of it. Pone can, and that may account for their abundance and widespread distribution on coral reefs.
Every several years or so, pone have a very successful spawning event, and uncountable numbers of their young (pala'ia) settle onto the reef. Pala’ia are very pretty and look like small dark alogo. But their beauty fades as they grow, and in just a few weeks they turn brown in color.
Turtles in Trouble by P. Craig, NPS
In Samoan folklore, sea turtles were believed to have the power to save fishermen who were lost at sea by bringing them safely to shore. The Samoan word for sea turtle, “I'a sa,” translates literally to “sacred fish”, presumably because of this ability.
Samoans have traditionally harvested sea turtles for food, and the shell was often made into bracelets, combs, fishing hooks, and also was used in the headpiece worn by a princess during important dance ceremonies. Turtles were incorporated into Samoan songs and art, and there are even turtle petroglyphs (rock carvings) in Faga'itua and Leone. And, of course, there's the legend about the Turtle and Shark that appear in the sea at Vaitogi when villagers sing a special song.
It therefore seems extra unfortunate that turtle numbers in Samoa have declined so much that they are now considered endangered species. Although it is difficult to determine how many are left, it is clear that few females lay eggs each year in the whole Territory. This drop parallels the worldwide decline of sea turtles due to overharvest, loss of nesting beaches, and incidental kills in fishing gear. Pacific populations of one of our species (hawksbills) are “rapidly approaching extinction” according to a recent review.
Two turtle species, the green and hawksbill, are the most frequently found turtles in our local waters. The hawksbill or “laumei uga” (Eretmochelys imbricata) is usually the species that nests on Tutuila beaches. This is a solitary nester, and perhaps only 1 or 2 hawksbill females now use a suitable beach. The hawksbill is occasionally poisonous -- in the late 1950s, many people in Aunu'u got very sick after eating one.
Our other species is the green sea turtle (Chelonia mydas), named after the color of its fat. It is also found around our islands, but it nests primarily at Rose Atoll. These long-lived turtles have rather complicated life cycles that involve repeated long-distance migrations to and from American Samoa. They start life as eggs buried in beach sand. Once a female has laid her first group of about 100 eggs, she will return at 2-week intervals to lay more. In about 60 days, the eggs hatch and the little turtles dart into the ocean. Where they go is not known, but eventually they take up residence at some feeding area that may be far away from American Samoa.
There they remain for some 20-25 years until they become sexually mature, at which time they return to the very same beach where they came from. After laying eggs there, the adult females then turn around and go back to their distant feeding grounds. That's the basic pattern for most sea turtle species throughout the world. Swim far away to some nesting beach, then swim back to their feeding area, back and forth every few years thereafter.
We have some very interesting migration data for green sea turtles at Rose Atoll (see map below), where a tagging study was conducted in the mid-1990s. In all, 10 tagged turtles were recovered after nesting at the atoll. Eight swam 800 miles directly to Fiji (unfortunately two of them were eaten when they got there). Another went past Fiji to Vanuatu, and the last one went in the completely opposite direction to French Polynesia near Tahiti.
It's understandable why the adult turtles do not stay at Rose Atoll after nesting, because their favorite food (seagrass) is absent there. But I wonder why don't they just stay in Fiji where they have both seagrass and nesting beaches.
Anyway, this pattern of large-scale movements between a turtle's nesting area and feeding area means that turtle stocks in the South Pacific Ocean are all mixed together. While some of “our” turtles were caught in Fiji, the reciprocal is also true, turtles that feed in our waters probably originated from islands elsewhere in the South Pacific. This mixing greatly complicates conservation efforts. It means that region-wide cooperation among the island countries of the South Pacific is essential; otherwise, while we try to protect turtles in American Samoa, our turtles may be killed later when they migrate to other islands.
Tough federal and territorial laws exist in American Samoa to protect turtles and their eggs, because they are an endangered species. There is a $10,500 penalty for killing a turtle or importing any turtle product into the Territory (shells, stuffed turtles, turtle combs, etc.). Fortunately fewer turtles seem to be taken in American Samoa, probably due to their scarcity but also due to outreach programs that inform children and villagers about the endangered status of the turtles.
In addition to education efforts, we must protect both the turtles and their habitat. Sandy beaches are essential for turtle nesting areas, so hauling sand away from our beaches results in the loss of critical habitat for these species. No beaches, no nesting turtles.
Although some villagers may still like to eat turtle meat and eggs, the point to remember is that turtles are a disappearing resource in American Samoa. They are a part of Samoa's heritage and need to be vigorously protected, or they may be lost altogether. It is a sad commentary that many young Samoans have never even seen a live sea turtle.
Whales Ho by P. Craig, NPS
September and October are the peak months when humpback whales (tafola) visit our balmy waters. It's almost impossible not to get excited when one is spotted. Most of us feel inexplicably privileged for a brief glimpse into their mysterious world, and there's an uncontrollable urge to shout 'thar she blows'.
Part of our fascination with whales is their huge size, of course. Adult humpbacks (Megaptera novaeangliae) grow up to 50 feet long and weigh about 40 metric tons (which equals the combined weight of 200 sumo wrestlers). We rarely get a chance to see the whole whale, except when they make a spectacular leap (“breach”) out of the water. We usually see only their air spout or their humped back as they prepare to dive:
Humpbacks are air-breathing mammals (like ourselves) that live their complete lives in the ocean. They reproduce like all land mammals, but they do it underwater. Whales obviously have to make sure that their babies don't drown while being born. Mother whales nurse their young for about a year.
These whales eat small schooling fishes and krill (small shrimps). They feed by sucking in tons of water in a single mouthful, and then strain the food out as they expel the water. The out-going water is filtered through specialized structures called “baleen”, which looks (with a little imagination) like a mouthful of coconut fronds. Humpbacks lack real teeth because they have no need to bite or chew their tiny food items. It seems odd that the whale, which is one of the world's largest animals ever, feeds on such small things.
The appearance of humpbacks in Samoa is an important segment of their grand migration up and down the South Pacific Ocean. During the warm months of the southern hemisphere, our whales feed in the rich waters of Antarctica, located 3,200 miles to the south of us (see map). Biologists call this particular group of whales the “Group-5 Antarctic stock”. When Antarctic's bitter winter sets in, the Group-5 whales seek warmer waters. They migrate northward, with some going towards Australia and others migrating towards Tonga. Apparently most of this latter group remains near Tonga, but at least some migrate onward to Samoa. However, one of our whales was sighted near Tahiti, so their migration patterns still hold some surprises for us.
A few humpbacks might arrive in Samoa as early as July or leave here as late as December, but they are most common here in September and October. They occur in small groups of adults or in mother-calf pairs. Humpbacks have been sighted around all 7 of the islands in the Territory, but we don't know how many are actually here. They migrate here to mate and give birth to their young. And, interestingly, they stop feeding while here, only when they return to the Antarctic do they resume feeding.
While an occasional spout of whale-breath can be seen in our local waters, you can also hear the whales if you stick your head in the water. Humpbacks are famous for their unique “songs”. Yes, whales sing! During mating season, male humpbacks sing to either attract females or to defend their territory from other male whales, much like birds do with their own songs.
The whale's song is haunting and complex. It sounds like a eerie series of chirps, squeaks, whistles and grunts. I know that “grunts” don't seem like they could make much of a song, but you just have to take my word for it. It is unlike anything you have ever heard. Scuba divers can hear the singing if the they hold their breath and pay attention. Snorkelers can also hear the songs, but they have to dive at least 10 feet deep to get below the noisy surface layer of water. The song lasts about 10-20 minutes, it has a beginning, middle and end, and all males of the same stock sing the same song. Biologists can therefore identify where a whale comes from by listening to its song. For example, Hawaiian humpbacks sing a different song (than the Samoan humpbacks), because they belong to a different stock of whales that migrates between Hawaii and Alaska. The whales' song is one of the world's wonders of nature and it's at our doorstep.
Humpback whales are currently listed as an endangered species because their world-wide populations were decimated by whalers in the 1800's and 1900's. By the time commercial whaling was stopped in 1966, 95% of our stock (Group-5) had been killed. Recovery of Group-5 has been unexpectedly slow, probably due to continued whaling by Soviet factory ships as late as 1972 and a subsistence harvest of these whales occurred in Tonga up to 1978. In any event, whales in American Samoa remain few in number, and in some years hardly any are seen here.
Because humpbacks use our waters to give birth to their young, it is important to protect them when they are here. Enjoy their presence, but don't pester them. Avoid the temptation to boat right up to them or follow them at close quarters. Boaters, divers and swimmers should stay at least 100 yards away, and watch from there.
Mammal Checklist
| Common Name | Samoan Name | Scientific Name | Origin |
| Samoan fruit bat2 | pe’a vao | Pteropus samoensis | N |
| White-naped fruit bat2,3 | pe’a fanua | Pteropus tonganus | N |
| Sheath-tailed bat | pe’ape’avai | Emballonura semicaudata | N |
| Common Name | Samoan Name | Scientific Name | Origin |
| Polynesian rat | isumu | Rattus exulans | PI |
| Roof rat | isumu | Rattus rattus | MI |
| Norway rat | isumu | Rattus norvegicus | MI |
| House mouse | isumu | Mus musculus | MI |
| Common Name | Samoan Name | Scientific Name | Origin |
| Pig | pua’a | Sus scrofa | PI |
| Dogs | Canis familiaris | PI | |
| Cats | Felis domesticus | MI |
| Common Name | Samoan Name | Scientific Name | Origin |
| Humpback whale | tafola | Megaptera novaeangliae | N |
| Sperm whale | Physeter catodon | N | |
| Dolphins | N |
Footnotes:
1 N = native, PI = Polynesian introduction, MI = modern introduction
2 Also known as flying foxes
3 Also known as white-necked, Tongan or insular fruit bat
4 A juvenile was caught on longline gear near Swains in 1993.
5 Ta'u Island
6 Tutuila Island
Reptile Checklist
| Common Name | Samoan Name | Scientific Name | Origin |
| Hawksbill sea turtle | laumei uga | Eretmochelys imbricata | N |
| Green sea turtle | laumei ena’ena, fonu | Chelonia mydas | N |
| Leatherback sea turtle4 |
| Common Name | Samoan Name | Scientific Name | Origin |
| House gecko | mo'o | Hemidactylus frenatus | MI |
| Mourning gecko | mo'o | Lepidodactylus lugubris | N |
| Pelagic gecko | mo'o | Cyrtodactylus pelagicus | N |
| Polynesian gecko | mo'o | Gehyra oceanica | N |
| Stump-toed gecko | mo'o | Peropus mutilatus | N |
| Common Name | Samoan Name | Scientific Name | Origin |
| Snake-eyed skink | pili | Ablepharus boutonii | N |
| Micronesian skink | pili | Emoia adspersa | N |
| Azure-tailed skink | pili | Emoia cyanura | N |
| Lawes skink | pili oua | Emoia lawesii | N |
| Black skink | pili uli | Emoia nigra | N |
| Samoan skink | pili lape | Emoia samoensis | N |
| Moth skink | pili | Lipinia noctua | N |
| Common Name | Samoan Name | Scientific Name | Origin |
| Pacific boa5 | gata | Candoia bibroni | N |
| Blind burrowing snake6 | Typhlops braminus | MI |
Footnotes:
1 N = native, PI = Polynesian introduction, MI = modern introduction
2 Also known as flying foxes
3 Also known as white-necked, Tongan or insular fruit bat
4 A juvenile was caught on longline gear near Swains in 1993.
5 Ta'u Island
6 Tutuila Island
| Common Name | Samoan Name | Scientific Name | Origin |
| Marine toad6 | lage | Bufo marinus | MI |
Footnotes:
1 N = native, PI = Polynesian introduction, MI = modern introduction
2 Also known as flying foxes
3 Also known as white-necked, Tongan or insular fruit bat
4 A juvenile was caught on longline gear near Swains in 1993.
5 Ta'u Island
6 Tutuila Island
Bats
Bats are the only native mammals found in American Samoa. They are harmless to people. There are two species of flying fox (fruit bat) and one insect eating bat species here. The fruit bats, the Samoan flying fox and the white collared flying fox, are as large as one pound with a wing span close to three feet. They eat pollen and fruits, serving an essential role in the ecology of the native rainforest by pollinating plants and dispersing seeds. the Samoan flying fox has the habit of flying during the day as well as the night. There are several locations in the park where these bats are likely to be seen; look especially along the ridges of the Amalau Valley on north-central Tutuila.
Flying Foxes (fruit bats) by Ruth C. B. Utzurrum, DMWR
Large flying foxes, also know as fruit bats, are one of the more unusual animals in American Samoa, especially for visitors from areas where bats are small and rarely seen. Three species inhabit our islands – two large fruit bats (Pteropus samoensis, P. tonganus) and a small insect-eating bat (Emballonura semicaudata; see Swiftlets & sheath-tailed bats). These three are the only native mammals in the Samoan islands.
The two flying foxes are especially distinctive: they are renowned for being large (with a wing span up to 3 feet wide) and active both day and night. Pteropus samoensis (pe'a vao)is commonly called the Samoan flying fox. It is presently found only in the Samoan Archipelago and Fiji. It once occurred in Tonga but is now extinct there. The other flying fox,Pteropus tonganus (pe'a fanua), has several common names such as the Insular, White-naped, White-necked or Tongan fruit bat. It has a wider distribution in the Pacific, ranging from islands off Papua New Guinea to the Cook Islands.
In American Samoa, flying foxes can be seen flying, soaring, feeding, or just hanging in trees. Although individuals of the two species overlap in size (adults weigh 300-600 grams), there are ways to differentiate them from a distance. When silhouetted against the sky, the pe'a vao has a more triangular shape, with wings that are slightly scalloped and relatively dark and opaque. Their flight appears more relaxed, usually with slower wing beats and deeper wing strokes. It is not unusual to observe them soaring in the air in the day, taking advantage of rising currents of warm air (thermals) to seemingly float up and about without flapping their wings.
In contrast, pe'a fanua has a more cross-like appearance: the neck and head appear more pronounced, the wings are narrower and more scalloped, and the hind legs stretch out like a tail. In flight, pe'a fanua tend to have faster wing beats and shallower wing strokes. They are less likely to soar in thermals and generally take a directional route to and from roosting sites at dawn or dusk.
Despite these differences, it takes keen eye to distinguish the two species from a distance. Close up, the pe'a vao may sport a white to yellowish triangular patch that starts from the forehead and extends to the back of its head, or it may simply exhibit a generally grayish head with or without flecks of white hair (much like a graying man). Its neck and shoulder areas are a beautiful russet brown, while the rest of the body has a dusty black appearance. The pe'a fanua, on the other hand, has a basically black head and body. These black areas serve to set off a distinctive band of creamy yellow on the back of the neck and which extends slightly below its shoulders as if in a cape. This explains why they are called white-naped fruit bats although the color is not really white.
The two species have quite different social behaviors. During the daytime, pe'a fanua form large roosting groups or colonies of hundreds to thousands of bats. These colonies are generally organized according to their reproductive status and may be composed of bachelor males, clusters of females defended by an adult male (suggesting a harem mating system), or groups of females and their young. In any case, individuals appear to be relatively “faithful” to their roosts, usually returning to their respective colonies following foraging flights.
But the pe'a vao does not do this. Instead, these bats usually roost singly on branches, or as pairs of males and females (suggesting a monogamous mating system), or as a female with its young. When roosting, pe'a vao males tend to hang from exposed or dead branches of trees on ridge tops while females roost in more covered positions on forest slopes.
There is little information on how long flying foxes live, although some held in captivity have lived 20 years. We assume that they live shorter lives in the wild, because natural catastrophes like hurricanes may periodically reduce their numbers, as occurred in the early 1990s. With proper management and protection from hunting, the populations will generally bounce back but this requires a number of years, because females of both species probably have only one young per year and we do not know how many of their young survive to adulthood.
The care and energy that both bat species put into their young is remarkable. Pregnancy lasts approximately 5 months in both species, and once the young are born, it takes at least another 3 months before they are weaned. Even after they are capable of flight, the young continue to receive parental care, perhaps until they reach adult size or become reproductively active themselves. We know this from observations of pairs of individuals seen to alight independently on the same tree and subsequently come together with one individual (presumably the juvenile) being wrapped up in the other's wings as they settle down to roost. Sightings of pregnant females and individuals carrying young in flight indicate that pe'a vao give birth mostly between April and June. Pe'a fanua births appear to occur year-round but are more common in January and June to August.
Although their name indicates that they are fruit-eaters, both species also eat nectar, pollen, leaves, and sap. They tend to consume only the “juice” of fruits and leaves. To do this, a bat will carefully chew on food (usually eating around large seeds), press the pulp against the roof of its mouth with its tongue, squeeze and suck in the juice, then spit out most of the pulp in pellets called “ejecta.” These ejecta are especially abundant under breadfruit trees (ulu) where the bats have been feeding overnight. Among the splatter of mushy bits of the fruit, you can find these pellets of drier material that sometimes show tooth and palatal (roof of the mouth) impressions, much like a dental cast produced at a dentist’s clinic. Ejecta pellets help us to identify food items that bats eat even when we do not directly observe them feeding. In addition to direct observations and analysis of ejecta, their diets are also determined through pollen present in facial hair and in feces. These data help scientists determine which plants are important because they are preferred, nutritious and/or available year-round.
At least 42 plant species provide food for the pe'a vao and pe'a fanua in American Samoa. These consist mostly of forest tree species, such as aoa (Ficus prolixa and Ficus obliqua), asi (Syzigium inophylloides), a’amati’e (Elaeocarpus ulianus), ifi (Inocarpus fagifer), fetau (Callophyllum inophyllum), mamalava (Planchonella samoensis), and tava (Pometia pinnata). The bats also eat fruits grown by man such as mango (Mangifera indica) and ulu (Artocarpus altilis), but damage to crops is limited if fruits are harvested before they ripen on the tree. Also, when you hear the bats squealing in banana patches at night, it’s usually because they are fighting over the banana flowers, not the fruits. Despite the broad similarity in their diets, pe'a fanua exploit flower resources and feed on trees (especially domestic ones) closer to human habitations more often than do pe'a vao.
The rewards of the interaction between flying foxes and plants are certainly not one-sided, because the plants and forest also benefit from being visited by bats. When the pe'a fanua visit patches of vavae flowers (Ceiba pentandra), for example, they help transfer pollen from one tree to another and that, in turn, enhances fruit formation and production. Flying foxes are also important for seed dispersal. When they consume fruits with small seeds (such as aoa), some seeds that get swallowed do not get digested but are carried and deposited away from the tree source. In American Samoa, flying foxes are the only animals that can carry fruits with large seeds, such as ifi, over distances and uphill. Studies of bat movements on Tutuila reveal that bats may commute between feeding areas up to 40 km apart during a single night. Seeds that are transported can colonize naturally bare or cleared areas and aid in the revegetation of gaps in forests where trees may have fallen from disease, age, or bad weather.
It may bother us that flying foxes eat some of the fruit that we grow for ourselves, but these bats are tireless workers that help maintain the health of our rainforest, and they are fun to watch.
Birds
On oceanic islands, birds are usually the most abundant and diverse animals. This park is home to more than 35 species, both resident and migratory, including seabirds, water birds, forest birds, and shore birds. The cliffs and sea stacks are ideal nesting habitat for tropical seabirds, while the rainforest is home to collared kingfishers, cardinal and wattled honeyeaters, bluecrowned lories, Samoan starlings, purple capped fruit doves, many colored fruit doves, Pacific pigeons, and banded rails.
The Pacific Pigeon (lupe), Samoa's Royal Bird by Pepper Trail, Joshua Seamon, DMWR
The lupe, or Pacific Pigeon, is the king of Samoa's birds and in many ways it is the most culturally important bird in our islands. It is our largest forest bird and is the only one able to feed on, and spread, the large seeds of some of our most important rainforest trees. Its cultural significance is revealed by the many Samoan proverbs that relate to the lupe and the art of lupe-hunting. The importance of lupe is also shown by the amazing tia seulupe (star-mounds) which are massive stone platforms built by the ancient Samoans, which served at least partly as pigeon-trapping sites.
The lupe is a member of a group of birds called the imperial pigeons because of their large size and dignified appearance. Most imperial pigeons live in the islands of the Pacific, although a few reach the mainland of Asia and one occurs in Australia. These birds are closely related to the much smaller fruit-doves, like the manutagi (Purple-capped Fruit Dove) but are only distantly related to the common pigeon that waddles around the cities of the world. The lupe is found from the islands north of New Guinea east through Fiji, Tonga, Samoa, Niue, and the Cook Islands. Interestingly, throughout most of this wide range, it is usually found on small islands and atolls, not on large 'high islands'. This is most striking in Fiji, where lupe are found on the small islands of the Lau group, but not on the large islands of Vanua Levu, Viti Levu or Taveuni. A closely related imperial pigeon replaces the lupe on those high islands.
Lupe are a common sight in forested areas of American Samoa, and can be seen flying high over villages or bays. They even visit moso'oi and poumuli trees near houses, if those houses are not too far from forests. Even when not seen, they announce their presence with easy to hear calls: a low, rising and falling moo like that of a cow, or a loud, rolling prrrrrhhh. One of the benefits of American Samoa's ban on hunting lupe (and pe'a) after the hurricanes in the early 1990s is that they become less scared of people, giving us better chances to see and appreciate these spectacular birds.
Their nests are hard to find. During all our time in the forests, we have seen only a few. We have also seen evidence of nest-building (for example, lupe flying with sticks in their bills) on several other occasions. All these observations were during the months of January through September. Lupe nests are open platforms of twigs, with no lining. They are usually placed in dense clumps of leaves high up in trees, making them very hard to see.
These birds lay only a single white egg. Both parents help incubate the egg and feed the chick once it hatches. All members of the pigeon family have an amazing ability: they feed their young a sort of “milk”. This is a nutritious liquid that is a combination of digested food and other substances secreted by special glands in the bird's digestive system. Both male and female pigeons make this milk, so both parents take an equal part in feeding the young. Information from related species of imperial pigeons suggests that lupe eggs take about 27 days to hatch, and that the young spend about 28 days in the nest after hatching. It seems like lupe could nest more than once a year, but most young birds are seen from July to August, so most nesting probably occurs at just one time each year.
Lupe eat many different rainforest foods, and not just fruits from favored trees like atone, ma'ali, malili, mamala, mamalava, moso'oi or aoa. They also eat fruits from vines such as mamalupe (pigeon's mouthful) and low shrubs like toitoi. Lupe eat leaves from many different trees, including au'auli, a'amati'e and ifi, although in almost all cases they like the young leaves best. This makes sense, since young leaves are probably the most tender and easy to digest, and may have fewer poisonous chemicals than old leaves. Lupe also like flowers on occasion, both from trees like ala'a or ma'ali and from shrubs such as ti.
Obviously, the lupe is not a picky eater. This may explain why it is such a widespread and successful bird, since it will eat food from both coastal and mountain areas. In fact, after Hurricane Val in 1991, many lupe on the coast near Vaitogi survived by eating the fruits of toitoi. Thus, in times of limited food, it can find food where other birds might not. At other times, lupe may eat unusual foods (like leaves and flowers) to get certain nutrients, just the way people sometimes take vitamin pills to supplement their regular diets. Lupe are also able to eat some fruits that smaller birds cannot, and so may be important for spreading these trees to new areas or even among different islands.
Since the lupe is such an adaptable bird, and has been able to recover both from human activities like hunting and from natural disturbances like the hurricanes in the early 1990s, it may seem surprising that there are many fewer now than in earlier times. The most dramatic evidence for this are the many tia seulupe, or star mounds, that were built by ancient Samoans. A survey discovered the remains of over 60 tia in the eastern part of Tutuila alone. Each tia is a massive stone platform with one or more arms extending from it. Pigeon-catching huts were built on top of the platform, and village chiefs competed to catch the most birds, using a tame lupe as a decoy, and a long-handled net to sweep up the flocks of pigeons that were attracted. Early missionary accounts tell how whole villages would spend weeks camping out in the forest around the tia, and that pigeon-catching season was a time of feasting and partying. Lupe must have been very abundant to support this elaborate cultural activity. While the tia certainly had ritual and religious importance in addition to their use as pigeon-catching sites, the latest studies suggest that pigeon-catching was central to their role in ancient Samoan society. A well-preserved star mound, with explanatory signs, can be visited in Ottoville, next to the Fatuoaiga Catholic Church compound.
Now, though, the rainforest that once covered the Tafuna Plain have been cut down. This type of lowland forest, with its abundant mamalava, tava, maota, mamala, and aoa trees, was almost certainly the best habitat for lupe in American Samoa. Today, only scattered aoa remain, and lupe are seldom seen in Tafuna. Even though aoa is a valuable food for lupe, we can see that it was the whole forest, and not just one kind of tree, that made the Tafuna rainforest so valuable to lupe. However, this large area of habitat is gone, and it seems we will never see as many lupe as did the first Samoans. Perhaps more than any other animal, the lupe is of irreplaceable importance to Samoa, both because of its natural role in spreading rainforest seeds, and its cultural role in the stories, proverbs, and heritage of the Samoan people.
The rare Many-colored Fruit Dove (manuma) Royal Bird by Pepper Trail, Joshua Seamon, DMWR
One of the rarest birds that nest on Tutuila is also one of the most beautiful: the manuma, or Many-colored Fruit-Dove.
The manuma here is considered a different subspecies than those from Fiji and Tonga because they have a slightly different color pattern. The male manuma is creamy white below and pale yellow above, with a dark crimson band across the back, a crimson patch on the forehead, and a purplish-red blotch on the breast. The female is very different and looks like the much more common manutagi, or Purple-capped Fruit-Dove. She is mostly green above and gray below, with a crimson forehead patch. Unlike the manutagi, the female manuma doesn't have a yellow band on its tail.
The manuma was not rare on Tutuila in the 19th and early 20th centuries, according to the journals of the early scientific expeditions. It was usually found in flocks; in 1923 a collector killed 10 birds with a single shot into a feeding tree on Ta'u. However, when the first modern studies of American Samoa's birds were done in mid-1970, only a small number of manuma could be found. Follow-up in the mid-1980's confirmed the manuma's rarity. They estimated that the population size on Tutuila was only about 80 birds.
After the hurricanes in the early 1990s, even fewer manuma were seen, and perhaps less than 50 remained on all of Tutuila. Today, however, manuma are regularly seen at some locations on Tutuila, although not in very large numbers. Biologists would call their current distribution rare and local, but they are occasionally sighted at many places around American Samoa. Interestingly, manuma are much more common in Fiji, Samoa and Tonga, sometimes being found well away from mature forests.
We know very little about the biology of manuma in American Samoa, or why it is less common here than elsewhere. These are social birds, often being seen in small flocks, but they are also very protective of feeding areas, driving other manuma away from their spot in the canopy of a fruiting tree. One odd thing is that you rarely see the same numbers of each sex -- almost always there are several more males than females in any flocks. We do know that they seem to have a very strong preference for the fruits of banyan (aoa) trees, and in American Samoa it is almost always seen near or in these trees. They are also known (from Fiji and Tonga) to eat moso'oi, o'a and magele fruits, all of which occur in America Samoa. Perhaps there are still so few manuma here that they are seldom forced to eat anything but their favorite food, but would eat other fruits if necessary.
It is dangerous for animals to specialize too much on any one food, especially on remote islands like American Samoa. This can be shown with an example from business. While a store that sells only antique cuckoo-clocks might do fine in New York, Los Angeles, or another big market, it would certainly fail very quickly in American Samoa. There isn't enough business here for such a specialized service. Similarly, an island animal that concentrates on only one kind of food may find itself in trouble when that food supply fails. An animal that lives on a continent can move in search of the food it needs, but island animals have nowhere else to go. On larger islands like Upolu, Savai'i or Viti Levu, manuma may be able to travel long distances to get the food they like the best. This may be difficult on small islands like those of American Samoa, and means that animals can only specialize on very reliable food trees such as banyan trees (aoa).
These giant banyan trees, which are so important to manuma, face many problems of their own. The Tafuna Plain used to have many huge banyans, but most of these have been cut down to make way for the exploding human populations in that area. Moreover, banyans, with their large size and spreading crowns, are very vulnerable to storm damage. Many were killed or severely damaged by Hurricanes Ofa and Val in the early 1990s. Even those that survived the hurricanes had their leaves and fruit stripped off, leading to a prolonged period of famine for manuma.
There are two things that must happen if the manuma is to survive and remain a special part of Samoa's wildlife. First, the birds must be protected from hunting. Although the manuma is too rare to be sought by hunters, a few may have been killed every year by hunters out for lupe and manutagi. When a population is as small as the manuma's, even a few preventable deaths per year are a significant problem.
The second thing that must be done if the manuma is to survive is to protect banyan trees on which they depend. Without enough banyans to assure a year-round supply of its favorite food, the manuma may well become extinct on Tutuila. People need to protect these magnificent trees, which are important food sources for many other Samoan wildlife species, including the fruit bats (flying foxes).
Birds of wetland and reef: Gray Duck and Reef Heron by Pepper Trail DMWR
Two very different birds depend on Samoa's shallow water habitats. One is the familiar matu'u, or Pacific Reef-Heron, a bird that is seen nearly every day by anyone visiting Samoa's shoreline. The other is Samoa's only duck, the toloa or Gray Duck, a bird that is so rare that most young Samoans have probably never seen one.
It comes as a surprise to some people that we don't have more kinds of ducks in Polynesia. After all, ducks like water, and we've got plenty of that, right? Well, we've got plenty of salt water, but very few lakes, marshes, or large streams of fresh water. Almost all ducks prefer fresh water, and even the few kinds of “sea ducks” eat mostly seagrass and other plants that aren't found around Samoa's coral reefs. Therefore, there aren't many suitable homes for toloa in American Samoa. These suitable homes are the fresh and brackish (fresh/saltwater mix) water wetlands.
“Wetlands” is a word that we've been hearing a lot lately. It refers to areas of land that are permanently or periodically flooded or submerged in shallow water. So much wetland habitat has been lost in the United States, primarily through draining and filling, that strict federal laws have been passed protecting wetlands. Locally, the Coastal Zone Management Program is responsible for protecting our remaining wetlands, which serve vital roles as nurseries for fish and crabs, natural water purification and recharge areas, sites for taro production, and homes for rare plants and wildlife. There used to be extensive mangrove (togo) swamps bordering Pago Pago Bay, but these were filled in long ago, before the negative environmental consequences of such activities were understood. The largest remaining wetland areas here are the pala lagoons in Nu'uuli and Leone and the marshes and Pala Lake on Aunu'u Island. There are also many other small but important wetlands remaining in both Tutuila and Manu'a.
All illustrations on this page used with permission from Dick Watling from “Birds of Fiji, Tonga and Samoa” and “Birds of Fiji and Western Polynesia” (Pacificbirds.com).
All of these areas were once home to toloa. However, as wetlands were filled in and as shotguns became available, this once-popular game bird became rarer and rarer. During a major survey of Samoan birds in 1986, not a single toloa was seen, leading to the concern that this bird might be extinct in American Samoa. Happily, this is not the case. A few toloa still live in the territory, mostly on Aunu'u, where the village leaders have taken an active role in protecting their ducks. This bird, and the wetlands it depends upon, need our continued protection if it is ever to recover to healthy population levels.
The toloa is a “dabbling duck”. This means that it doesn't dive under the water to feed, but rather tips down, with its tail in the air and its neck stretching under the water, to reach the plants and small insects and snails that it feeds on. Although it sometimes swims in the sea, it does not feed there, and, like most ducks, it does not eat fish.
One interesting thing about the toloa is that is doesn't always nest near the water. It may build its nest in tall dense grass, or place it in a low tree hollow. Five to ten pale green eggs are laid. The journey of the young ducks from the nest to the safety of the water is a dangerous one, and usually only one or two ducklings make it.
The toloa is a great wanderer. The bird is found across a huge geographic area, extending from Indonesia to French Polynesia, and south to New Zealand and Australia. The toloa is a strong, fast flier, and commonly flies between islands. It seems likely that the small population on Aunu'u, which was apparently absent in the late 1980's, may have recolonized American Samoa from western Samoa, where the duck is slightly more common. This gives us reason to hope that the toloa may return to areas that it formerly used, if the wetlands are preserved, and the duck is protected from hunting. So ... if you see a toloa, consider yourself lucky, and please don't disturb it. Perhaps one day Samoa's special duck will once again be a common sight.
The matu'u, or Pacific Reef-Heron, is a common sight today. With its long legs and long neck, often curved in an S-shape, the matu'u is one of Samoa's most recognizable birds. One interesting fact about the matu'u is that it comes in two color forms, either dark gray or pure white, although almost all the matu'u in Samoa are dark gray. In other areas, particularly atolls like Swains Island or Rose Atoll, almost all the matu'u are white. It seems that in Polynesia the dark forms are found on volcanic islands, with dark lava rocks, while the white birds occur on atolls with white sandy shorelines. In many other parts of its range, however, including Fiji, both white and gray forms occur commonly in the same area. The reason for the matu'u's two color forms remains a unclear.
The matu'u is the master spear fisherman of the bird world. It stalks slowly across the reef flat, scanning for the slightest movement, and then throws its long neck forward as fast as lightning, catching its prey with its long sharp beak. It feeds on a wide variety of reef creatures, including fish, crabs, and snails.
Although the matu'u usually makes its living feeding on the coral reef, it also uses the freshwater wetlands of Samoa. Mangrove areas like the Nu'uuli Pala are frequent feeding sites, and the birds will also hunt for food in freshwater streams. These rainforest stream valleys are the matu'u's favored nesting areas, where the herons build their large nests high in the trees. Some matu'u also nest on offshore islets, and have even been reported to nest on ledges in caves. Usually three pale green eggs are laid.
Strict protection of Samoa's wetlands is essential if the toloa is to regain its place among our familiar native birds and if the matu'u is to continue to be a common resident of our shoreline villages. Please help spread the message that landfills kill a very important part of Samoa's natural environment - our wetlands.
Shorebirds (o tuli): Incredible Voyagers by Pepper Trail DMWR
April/May is the time of year when some familiar visitors leave American Samoa and begin an incredible and perilous journey home. These visitors are the shorebirds, or tuli. Three different kinds of tuli are common visitors here between the months of September and April: the Pacific Golden Plover, the Wandering Tattler, and the Ruddy Turnstone.
During the northern summer, all three tuli nest in Alaska and northern Canada. The plover and the turnstone nest in the tundra, where their neighbors are caribou and grizzly bears. The tattlers nest by icy mountain streams, sharing their world with mountain sheep and golden eagles. But when the northern days grow shorter and colder, the birds probably begin to dream of the beaches and reefs of Polynesia, for they set out on one of the greatest of all animal journeys. From gathering places on the coasts of Alaska, the tuli take off to fly non-stop over 3,000 miles of open ocean to the Hawaiian Islands. These birds cannot land on the water and take a rest -- their feathers are not waterproof, so if they land in the water, they drown. Not only is this flight an amazing physical feat, but it requires tremendous navigational abilities to find tiny specks of land lost in the featureless sea. After a well-earned rest in Hawaii, the tuli take off again for another flight over thousands of miles of ocean to reach Samoa.
Here, each kind of tuli takes up a slightly different lifestyle. The Golden Plover is often seen on the beaches, but even more commonly can be found searching for food on the short grass of malae, parks, the golf course, and the airport. We can only hope it will not be harmed from competing with the many myna birds that now occupy these areas.
Although this plover is plain brown during most of its stay in American Samoa, it gets a beautiful new set of feathers just before it heads north: a golden-spangled back and jet black underparts. The plover is the commonest tuli in Samoa, and it features in many myths and legends. Tuli the Messenger is one manifestation of Tagaloa, the supreme god of the ancient Samoans, and in one version of the Samoan creation story, Tagaloa created the first dry land as a resting place for tuli.
The Wandering Tattler is a beachcomber. It is almost always seen on beaches or the reef, using its long beak to pry small crabs, worms, and other delicacies out of the sand or coral. It is a solitary bird, soberly dressed in gray. When disturbed, the tattler's loud cries explain how it got its name.
The turnstone was named for its way of feeding. These small, energetic, sociable birds like to vigorously flip over small stones, bits of seaweed, or debris in search of food hiding beneath. They can be seen either on the beach or in grassy areas. The turnstone has a beautiful pattern of black and white patches on its back when it flies, and in breeding plumage, it is a handsome bird with orange-brown, black, and white patterning.
All these tuli can usually be seen in such places as Sliding Rock and Pala Lagoon from September to April. But in April/May, all but a few stragglers will have left Samoa to take their long, long trip back to Alaska. So, the next time you see some tuli, wish them a safe journey and try to imagine, maybe with a little envy, their great adventure.
Incredible flight of shorebirds (tuli) from American Samoa to Alaska and Canada, with a stopover in Hawaii.
Samoa's seabirds: tava'e, gogo and manu sina by Pepper Trail DMWR
The islands of Samoa are true oceanic islands: they are not riders on the skirts of any continent, but are the tops of huge mountains, rising up through the great ocean depths. Surrounded as they are by thousands of square miles of ocean, it is not surprising that the Samoan Islands have more kinds of seabirds than any other type of native wildlife. In all, 20 species of seabirds are known to nest in Samoa (and many more can be seen passing through our area), compared to 18 kinds of landbirds and only three kinds of mammals (all bat species).
Our seabirds are a diverse group. Some, such as shearwaters and petrels (ta’i’o), are rarely seen, but nest in burrows on the tops of mountains like Lata and Pioa. Their eerie calls can be heard at night in places such as Afono Pass. Others like frigatebirds (atafa) and boobies (fua'o) are seen flying around our coasts, but nest on the high cliffs of Pola or in trees on the remote north side of Tutuila. The tern family has many different looking birds living here, including the solid black and brown noddies (gogo), the beautiful blue-grey noddy (laia), the white tern (manu sina), and the grey-backed tern (gogo sina). Here we will discuss the three most common and conspicuous seabirds of Tutuila: the tava'e, manu sina, and gogo.
The tava'e (tava'esina), or White-tailed Tropicbird, is one of Samoa's most beautiful creatures. The sight of a tava'e soaring overhead is unforgettable, as its gleaming white feathers and graceful tail streamers blaze against the deep indigo of the Polynesian sky. Happily, it is also a familiar sight, as these birds are common all around Tutuila.
The tava'e, so graceful in the air, is comical and awkward on land, so much so that Samoan legends describe the bird as lazy or dim-witted. In fact, tava'e are probably as industrious and intelligent as your average bird. Their awkwardness results from the fact that their legs and feet are tiny for the size of the bird, and are placed far back on the body. Thus, all tava'e can do on land is to shuffle along, bumping their powerful chest muscles on the ground. Luckily for them, tava'e spend little time on land.
They typically nest high in rainforest trees, preferring protected sites such as large hollows or clumps of ferns or other plant material. Here they lay a single large egg. At hatching, the young tropicbird is one of the cutest of all baby birds - a completely round ball of silvery fluff. As they grow, they molt into their juvenile plumage, with black and white barred feathers across their back. This is their appearance when they leave the nest on their first flight toward the sea, often a mile or more away. The fledglings often seem to have problems with this flight, based on the number of young tava'e that are brought in to our office, unable to fly. These youngsters are usually very gentle, and with several days of feeding with sardines or other fish, they often regain their strength and are able to fly away.
Tava'e are master fishermen, making plunging dives for squid and a variety of small fish. One of their favorites are flying fish, I've often wondered whether they catch the flying fish in the air or while they're swimming. The tava'e is well known to Samoan fishermen, who watch its behavior at sea to help them locate schools of masimasi and other fish. The tava'e is important to human fishermen for another reason: its feathers are prized for fishing lures. The gleaming white breast feathers are tied to hooks and used to attract malau (squirrelfish) and other fish. It is a traditional belief that only feathers from living birds stay dry and shiny after repeated use, and it was a badge of honor for a Samoan youth to climb a tava'e nesting tree and pluck out the plumes. This supplied a lure while causing no harm to the birds.
The tava'e has a close relative, the Red-tailed Tropicbird, or tava'e'ula, that nests on Rose Atoll. This bird is larger and heavier than the tava'e, with shining pinkish-white feathers and red tail plumes. It typically nests on the ground among rocks, roots, or logs. In former times, this bird apparently nested on Tutuila, but it no longer does so. The reason may be the abundance of introduced animals such as rats, cats, and dogs that attack ground-nesting birds on Tutuila.
Our next seabird, the manu sina or manusina (also called the white tern or common fairy tern) is perhaps Samoa's most familiar bird. At almost any time of day you can lift your eyes to the mountains and see these pure white birds circling effortlessly over the green forest. I recommend contemplation of this lovely sight to anyone feeling burned out by the noise and ugliness that sometimes surround us at eye level. It's always a nice reminder of the beauty of the natural Samoan environment.
The manu sina is found throughout the tropical oceans of the world and seems able to adapt to human-altered landscapes better than do many seabirds. Those of you familiar with Honolulu may have noticed manu sina fluttering in the trees along Kalakaua Avenue, where they actually nest in the middle of Waikiki.
The nesting behavior of manu sina is remarkable indeed. In fact, “nesting” is being a bit generous, since manu sina make no nest at all. Instead, they balance their large single egg in a knothole, stub, or other more or less precarious perch in a tree. They will even accept man-made structures like rooftops and ledges. It is amazing to see a manu sina stubbornly sitting on its egg as a strong tropical storm swings its branch wildly. Risky though is seems to us, this nesting strategy certainly works, as the White Tern is a common and widespread bird.
Manu sina feed on a variety of small ocean fish, which they pluck from the surface. Unlike all the other seabirds of Samoa, the manu sina carries fish back to its chick in its beak, rather than swallowing them first. In fact, they have the incredible ability to capture several tiny fish in a row, shift them crosswise in their bill, and carry them back home, without dropping a one. How do they do it?
The final seabird to be discussed is the gogo, or Brown Noddy. Like the manu sina, this bird is a member of the tern family, but these two cousins are different in many ways. For starters, the gogo is as dark as the manu sina is light. It is dark chocolate brown all over, except for the top of the head, which is a whitish-gray cap. It is also more sociable than the manu sina, usually nesting in loose groups, or colonies. The gogo is very flexible in its nesting behavior. On Tutuila, gogo usually nest high in trees in forested stream valleys, building bulky nests of dead leaves and other plant material. They also sometimes nest on cliffs, for example at Fagatele Bay. On Rose Island and other atolls, gogo are happy to lay their eggs on the ground, making only a small scrape in the coral rubble, which they often decorate with empty seashells and even bones. Like other tropical seabirds, the gogo typically lays only a single egg.
There is another gogo here, the Black Noddy, which is smaller and blacker than the Brown Noddy, and has a different way of flying. In good light they are separated from Brown Noddies that have a distinct brown and black pattern on the wings. Black Noddies are more often seen feeding in flocks with manu sina than are Brown Noddies. The diet of the gogo is apparently similar to that of the manu sina, since both birds feed on small fish and squid captured near the surface. How do different birds with such similar food habits coexist? Maybe each catches just a particular kind or size of fish, or dives to a certain depth.
One of the most interesting sights in American Samoa is a foraging flock of seabirds. These groups can have from five or ten to hundreds of birds. They are a great chance to see the many different ways seabirds catch fish: laia flutter above the waves, sometimes dangling their feet into the water, gogo swoop low over the water, fua'o dive into the water with a huge splash, and atafa wait until a fua'o catches some fish, then chase it and take the fish from it. The birds you see in such a flock are a good indication of which fish are below the water, something Samoan fishermen use to locate schools of fish. A flock of small birds like White Terns and Black Noddies usually indicates skipjack or small tuna, while large flocks of fua'o indicate larger fish.
As fishing partners or simply as beautiful neighbors on our islands, Samoa's seabirds are a special part of our wild heritage.
Our strange winter visitor, the cuckoo (aleva) by Pepper Trail DMWR
The aleva or Long-tailed Cuckoo is a very odd bird, no doubt about it. For one thing, when the weather starts to get cold in its summer home, the aleva migrates north for the winter. For another, it has a highly unusual home life: it doesn't build its own nest or care for its own young, but abandons its eggs in the nests of other birds, to be raised not only by strangers, but by completely different kinds of birds. The aleva lives and breeds in New Zealand for half of the year. But when winter approaches, around March or April, the aleva leaves its chilly home islands, and flies north into sunny Polynesia. In fact, it is the only land bird to migrate north to spend the winter with us (although a few aleva may be found here year-round). The aleva's winter range extends all the way from Palau on the west to Pitcairn Island on the east, but the largest numbers winter in Fiji, Samoa, and Tonga. Here it can be found on any island, from the mountainous interiors of the largest high islands to the coastal vegetation of tiny atolls. Wherever it ends up, the aleva feeds mostly on large insects, including caterpillars and stick insects, but also small lizards.
The aleva is a hard bird to see, usually creeping without a sound through dense foliage. In fact, we most often see aleva because they are being chased by other birds, especially the iao (Wattled Honeyeater). Iao seem to hate aleva, and chase them vigorously, with loud scolding cries. It is very interesting to try to figure out why they do this. There are at least three possibilities. It may be that aleva will eat eggs if they get the chance; however, this has never been observed. Second, in flight the aleva looks much like a hawk, with its pointed wings and long tail. Perhaps iao mistake the aleva for a hawk, and think they are chasing a dangerous predator away. But there are no hawks in Samoa. Therefore, this explanation would mean that iao still have an instinctive fear of hawk-like birds thousands of years after they last saw a hawk (which was probably when the ancestors of our iao came here from Fiji). The last explanation seems even more far-fetched. This is that the iao chases the aleva because it is afraid that the cuckoo will lay its eggs in the iao's nest. To understand this possibility, we must discuss the strange breeding behavior of the aleva.
Like many other members of the cuckoo family, the aleva is a nest parasite. This means that it secretly lays its eggs in other birds' nests. The unlucky host birds think that the cuckoo egg is their own, and raise it alongside their own babies. Usually the baby cuckoo is much larger than the babies of its hosts, who are unable to compete and starve to death. Many New Zealand birds, including honeyeaters related to the iao, recognize the aleva and chase it away. This makes a lot of sense in New Zealand, where the aleva breeds. But the aleva never breeds on its wintering grounds in Polynesia. Therefore, the iao has no reason to fear that the aleva will lay eggs in its nest. Could there be an instinctive hatred of cuckoos in all members of the honeyeater family? Like many questions in biology, this one would be hard to answer, but it's still fun to think about.
Many older Samoans say that aleva used to be much more common than they are today. The aleva is now a rare sight on Tutuila. It's hard to know just how rare the bird really is because of its secretive habits. If you see one, consider yourself lucky, and take a moment to think about the many mysteries in the life of this strange visitor to our shores.
Barn owls (lulu) - spirit of the night by Gilbert S. Grant, DMWR
The barn owl or lulu is a highly beneficial bird in American Samoa, but some people fear it because they associate it with ghosts or aitu. Its ghostly white appearance and its preference for flying at night enhance its reputation as a mysterious bird. It is not uncommon when driving around Tutuila at night to see one perched on a telephone pole or gliding across the road. Its eerie screech pierces the night and can be frightening if you are not expecting it.
Owls are carnivores that usually swallow their prey whole. A few hours after swallowing a rat (isumu) or some other prey, owls regurgitate or spit out a pellet of indigestible bones and hair about two inches long and one inch in diameter. By examining these pellets, we can determine what the lulu eats. In the remains of 482 meals, rats made up most (81%) of those meals, followed by mice (9%), geckos (7%), and bones of a few birds (2%), which consisted of White Terns (manu sina), Wattled Honeyeaters (iao), mynas, and Samoan Starlings (fuia).
No chicken remains were found, but this was not unexpected because owls do not generally attack large prey. Chickens and fruit bats (pe'a) are too heavy for an owl to carry and too large to swallow whole. Instead, they would typically eat the meat and viscera at the site of the kill. Soft tissues such as these would be totally digested and not be found in pellets. We have other evidence that one flying fox was killed and partially eaten by an owl.
Even though lulu occasionally take a bird, bat or even a chicken, their value in controlling rat populations is tremendous. One pair of owls may catch 2-4 rats per day. Without owls, Tutuila and Manu'a would probably be over-run with rats. A lulu seen flying through a village should not be feared or hated but welcomed, because it will probably mean one less rat near your fale.
Familiar and mysterious birds - the rails by Pepper Trail DMWR
The ve'a, or “roadrunner”, is one of Samoa's most recognizable birds. It is a familiar sight tiptoeing out of the grass or running crazily across the road, its neck stretched out and its big feet trying to keep up. And its loud, screeching voice is a familiar sound, seeming to complain at the disturbance as we walk to the taro patch. However, for all its abundance, the ve'a is still a little-known bird, quickly disappearing from view when disturbed and impossible to follow in the thick grass it favors. What's more, the ve'a has two even more mysterious cousins in American Samoa, and another in western Samoa that, as we will see, is the most mysterious Samoan bird of all.
The ve'a and its cousins belong to the family of birds known as the rails (named from a old English word meaning to screech - many of these birds have loud, harsh voices). The ve'a is called the Banded Rail, because of the black and white bands on its sides and underparts. It is found all across the Pacific from the Philippines and Indonesia to Samoa, Tonga, Fiji, and on to Australia and New Zealand. It is usually common wherever it occurs, with the exception of Fiji. On Fiji this formerly abundant bird has been exterminated on the large islands of Vanua Levu and Viti Levu by an introduced predator, the mongoose. This shows how important it is to keep Samoa free from such destructive introduced animals.
The ve'a is a very useful bird, eating many insects that can harm crops. In fact, it will eat almost anything, including fruit, worms, snails, mice, and even toads squashed flat on the roads. It sometimes can be seen deep in the forest, but prefers open areas with dense grass. Therefore, taro and banana plantations are some of its favorite places. The nest of the ve'a is very hard to find, being built on the ground well-hidden in thick grass. The ve'a lays 4 to 6 eggs. Like young chickens, young ve'a can run around almost as soon as they hatch, and they leave the nest immediately. It is common to see one or two fuzzy, dark gray chicks being led into the grass by their watchful parents.
The other Samoan rail that most people know is the manu ali'i, known as the Purple Swamphen. This large and beautiful bird is a dark purple, with a bright red beak that extends up over the forehead. It is even more widely distributed than the ve'a, occurring from southern Europe through Africa and all the way to Australia and New Zealand. It is much less common than the ve'a in American Samoa, but occurs in low numbers almost everywhere, especially in more remote plantation areas. This bird is more often heard than seen; it gives a loud screech with an echoing, honking quality.
Like the ve'a, the manu ali'i prefers areas with thick undergrowth rather than true forest. It has a very wide diet, including many insects and much plant material. It sometimes gets into trouble with farmers because of its fondness for green bananas and taro tops. However, usually it does little damage, and repays it by eating soldier worms and other crop pests. In former times, the manu ali'iwas sometimes hunted, and this may be why it is so shy, usually running or flying off with loud screams as soon as it sees you. Like the ve'a, it nests in thick vegetation, either on the ground or in a low bush. It lays 3 or 4 eggs, and the young leave the nest to follow their parents as soon as they hatch.
Our third kind of rail is a real mystery bird, as shown by the fact that it has no Samoan name. In English it is called the Spotless Crake. Although its wide range in the Pacific is very similar to the ve'a, in American Samoa it has only been sighted on the island of Ta'u. The Spotless Crake is very small, only about half the size of a ve'a, and is all dark gray except for red legs and eyes. It lives in dense grass, almost never flies, and is active at dawn and dusk. All this makes it a very hard bird to find. In fact, only a single bird was seen by biologists in 1986, and another was sighted in 2001.
There is one more kind of rail to mention, and this is the most mysterious Samoan bird of all. It is the puna'e, or Samoan Woodhen. This bird was first described by scientists in 1874, and last seen in 1908. In the whole world, only 11 preserved specimens of it exist. It apparently occurred only on Savai'i in western Samoa.
Old stories tell that the puna'e lived in burrows in the mountain forests, and that it was formerly so abundant that it was hunted with nets and dogs specially trained to tell which burrows were occupied. If these stories are true, the puna'e was a very special bird indeed, since no other rails live in burrows. In the last ten years, there has been an unconfirmed report of the puna'ebeing seen in the mountains of Savai'i. These remote forests have been rarely visited by biologists, and we can hope that this unique bird may yet survive in the depths of that misty wilderness.
Swiftlets & sheath-tailed bats (o le pe'ape'a): A mosquito's nightmare by Pepper Trail DMWR
High above the villages, valleys, and mountains of Samoa flies a deadly predator, as terrifying as a tiger shark - if you're a mosquito (namu), that is. This is the pe'ape'a, the only bird in Samoa that lives entirely on a diet of insects.
But wait a minute - pe'a means bat: isn't the pe'ape'a a kind of small bat? Well, yes and no. Actually two completely different creatures share the name pe'ape'a in Samoa. One is a bird, the common White-rumped Swiftlet that is seen flying by day all over our islands. Like all birds, this pe'ape'a has feathers and lays eggs. The other pe'ape'a, more properly called pe'ape'avai, is a tiny bat, the Sheath-tailed Bat that is active only at night. This animal is now almost extinct in American Samoa. Like all bats, this pe'ape'a is a mammal and has fur and gives birth to live young that it feeds milk. The confusion arises because both creatures are tiny, active insect-eaters that are almost always in flight, and look similar as they dart and swoop after their prey.
First let's talk about the common pe'ape'a: the bird. It belongs to a family of birds that are truly creatures of the air, the swifts. They have tiny legs and feet, and never land except at nests or in their roosting caves. Capturing and eating food, drinking, gathering nesting material, and yes, even mating, are all done in flight. In fact, it is likely that the pe'ape'a is like many other kinds of swifts and actually sleeps while flying. With their long, powerful wings and perfectly streamlined bodies, pe'ape'a are beautifully adapted for a life of flight.
As they fly, pe'ape'a are continually hunting for small insects, especially mosquitoes, flies, and flying ants and termites. These are scooped up in the swift's huge mouth, which is made into an even larger trap by long bristle-like feathers around the mouth. The swiftlet is a very useful bird because of all the insects it eats.
When the pe'ape'a finally does decide that it's time to land, it heads for a cave or a protected overhang on a cliff. There it flutters in to grasp the rock, usually hanging vertically. These caves and sheltered overhangs are also the nest site for the swifts. The nest is a small platform made of moss and fine twigs cemented together with the bird's saliva, attached to the rock. Some close relatives of the pe'ape'a make their nests entirely from dried saliva, which (believe it or not) are collected and cooked up to make that famous delicacy, bird's nest soup. The nests of our pe'ape'a are not suitable for this, so anyone with a taste for bird saliva will have to look elsewhere.
Swiftlets lay one or two white eggs, and appear to nest at any time of year in Samoa. Although most nests are placed where at least a little light penetrates the cave, some are far back, where it is completely dark. How do the swifts find their way in and out? The answer is that these birds, like many small bats, have the amazing ability to echo-locate. They give loud clicking calls, and then listen to the echoes to orient themselves and avoid the walls of the cave. This ability is fairly undeveloped in birds, and the swiftlets don't use it to locate their insect prey, which is why they hunt during the daytime. In many small bats, however, echo-location is incredibly advanced, and is used to hunt tiny insects in complete darkness. One bat with this ability is the Sheath-tailed Bat, which brings us to our second pe'ape'a.
The Sheath-tailed Bat (Emballonura semicaudata) also feeds on mosquitoes and other flying insects. But unlike the swift, this small bat does not seem to accept sheltered cliffs as roosting or breeding areas, inhabiting only deep and protected caves. There are few such caves in American Samoa, and therefore few good homes for the bat. Ever since Hurricane Ofa in 1990, the known bat caves on Tutuila have been almost deserted. Hurricanes Ofa and Val swept water and debris into several caves, and the days of strong hurricane winds may have made it impossible for the bats to find food. Unless more bats survive in caves that we don't know about, the long-term survival of this useful and fascinating animal in American Samoa is doubtful. There is little we can do to help the bat except to stay away from their caves to avoid disturbing the few surviving animals. Sadly, the Sheath-tailed Bat seems to be endangered throughout most of its range, including in western Samoa and the Marianas, as well as here.
And what about the swift? Although the population of these birds was reduced by hurricanes in 1990-91, the species seems to be in no danger of extinction. It is still possible to see flocks of hundreds of swifts swirling together in areas where winds collect large numbers of insects, for example in Malaeimi Valley and in such highland areas as Aoloau and Afono Pass. There is every reason to believe that these birds will always enliven the Samoan sky - and strike terror into the
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by John William Uhler
