Technical note usda natural resources conservation service pacific islands area



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HABITAT REQUIREMENTS
Fanihi mainly forage and roost in both native limestone and volcanic forest, but also secondary native-nonnative mixed forest, forest patches, and coastal strand. Tangantangan forest, farmlands, and developed areas are used infrequently (34). In Palau and Yap, mangroves and agroforests are also important (35,36). Habitat examples:



  • Cropland. Coconut groves for foraging and roosting

  • Forest land. Native limestone and volcanic forest, secondary native-nonnative mixed forests, and mangrove forest for foraging and roosting; agroforests for foraging

  • Other rural land. Rural yards for foraging

  • Rangeland. Coastal strand and savanna with trees for foraging and roosting


Food. Fanihi are primarily frugivorous, feeding on fruit, nectar, and pollen and occasionally flowers and leaves. They feed on at least 39 species of plants in the Marianas. Of these, 72% are native (37). Bats usually begin feeding about sunset and return to roosts before sunrise, but can also be seen during the day. Fanihi have well developed sensory organs and locate food by sight and smell. Foods include fruit of pandanus, breadfruit, fig, fagot, cycad, tropical almond, and false elder and the nectar of kapok, coral tree, and coconut flowers (See Appendix B).
Cover (foraging). Fanihi forage in native forests and other forests where human activity is infrequent, but may venture into rural areas in search of food particularly after typhoons have depleted regular food sources (38). In Palau and Yap, bats regularly forage in mangrove forests (35), pandanus savanna, and agroforests (36).

Fanihi foraging on (left to right) a liana flower, cycad fruit, and kapok flower (Photos © Merlin D. Tuttle, Bat Conservation International).


Cover (roosting). Large emergent trees with easy access for bats, such as banyan, ironwood, breadfruit, pengua, yoga, fagot, and chopak are regularly used for roosting. On Guam, fanihi roost primarily in native limestone forest along steep cliff faces largely inaccessible to humans (34). On Sarigan, where there’s little human disturbance, roosts are located in stands and patches of volcanic forest and isolated coconut trees in savanna (33). On Yap, bats regularly roost in mangroves and secondary forests (36). Colonies may relocate if disturbed by people, but may use favored roost sites for long periods if left undisturbed.


Fanihi roosting in a banyan tree in native limestone forest on Guam (Photo © Merlin D. Tuttle, Bat Conservation International).





Water. Moisture in ripe fruit and other foods meets water requirements. Bats also lap up rainwater from leaves.

Interspersion of habitat components. Suitable roosting habitat near suitable foraging habitat with minimal or no disturbance generally allows bats to forage efficiently and dedicate more time and energy toward successful reproduction (36).
Minimum habitat area. The species requires large areas that can encompass multiple landowners. Foraging distances are similar to other medium-sized, Pacific Island flying foxes. For instance, 2 of 3 radio-collared fanihi in primary and secondary forest commuted approximately 2-3 miles (4-5 km) from day roosts to night foraging areas (the third flew up to 11 miles [18 km]). Foraging areas ranged from 35-270 ac (14-110 ha), but bats spent most of their time in core areas of about 14-30 ac (6-12 ha). Foraging areas vary by habitat type and quality (39).

SAMOAN FLYING FOX

Federal – Species of Concern

American Samoa – Protected Species

I

Species Profile

Samoan flying fox, pe‘a vao

Photo A. Brooke


Scientific name: Pteropus samoensis

Habit: Generally solitary, diurnal and nocturnal

Average wingspan: 34 inches (86 cm)

Weight: 7.8 - 15.5 oz (220 - 440 g)

Range: Polynesia

Breeding period: Year-round

No. of pups per year: 1

Roosting habitat: Primary and secondary forests, forest edges, large trees in pasturelands

Foraging habitat: Primary and secondary forests

Food habits: Frugivorous - eats primarily fruit, also nectar, pollen, flowers, and leaves

Population estimate: 1000 - 1500 (Tutuila, American Samoa)
NTRODUCTION

The Samoan flying fox or pe‘a vao is one of two medium-sized members of the old world fruit bat family (Pteropodidae) in the Samoan archipelago. Its body is dusty black with russet-brown on its neck and shoulders. Its head can have yellowish or whitish patches or be grayish (40). While most fruit bats are nocturnal and roost in colonies, pe‘a vao is unique because it roosts alone or in small family groups and is active during the day and night (41). The long-term survival of pe‘a vao is dependent on hunting limitations and protection of primary forest tracts (42).
STATUS & DISTRIBUTION
The species distribution includes the islands of Samoa, Fiji (2 subspecies) and, based on the fossil record, formerly Tonga. In American Samoa, resident populations of pe‘a vao occur on Tutuila, Aunu‘u, and Manu‘a at a wide range of elevations (41). The population estimate for Tutuila is currently about 1000-1500 bats (19,42,43), but is uncertain for other islands. Pe‘a vao were able to rebound from being overhunted after hunting was banned in 1992. Overall, the American Samoa population is believed to be locally stable but in need of ongoing protection due to illegal hunting, habitat loss, and hurricanes (19).
REPRODUCTIVE CYCLE
Females generally bear one pup per year. Pregnancy lasts about 5 months. Most births occur April to June, however, births have been recorded March to November. Pe‘a vao pups have been observed year-round, but more often between March and October. Pups fledge (begin to fly) at about 2-3 months but remain dependent on their mother’s milk until 4-6 months of age or more. The final stages of pup-rearing may overlap with mating (40-42).


Periods of breeding activity in pe‘a vao (40-42)

Activity

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Mating

Gest




































Pregnancy





































Pup births





































Pup-rearing





































Pup fledging





































Peak Off-peak
HABITAT REQUIREMENTS
Pe‘a vao roost and forage in mainly primary forest, but also secondary forest and agroforest. Developed areas are used infrequently or not at all. Habitat examples:


  • Cropland. Coconut plantations for foraging

  • Forest land. Primary forest, secondary forest, and agroforest for foraging and roosting

  • Other rural land. Rural yards for foraging

  • Rangeland. Large trees in pasture for roosting


Food. Pe‘a vao are primarily frugivorous, feeding on fruit and occasionally nectar, pollen, flowers, and leaves. They feed on at least 32 species of plants. Of these, 91% are found in primary forest. They typically begin to forage in late afternoon and may return to the roost as late as mid-morning (44). Preferred fruit include those of the māmālava, ‘ala‘a, tropical almond, and probably banyan. Flowers of asi, māmālava, and ‘ie‘ie are frequently visited. Leaves of trees such as the Polynesian chestnut, breadfruit, and fig are eaten in small amounts year-round. Leaves also serve as a post-hurricane food when regular sources are scarce (29).

Māmālava, Planchonella samoensis (Photo A. Whistler).


Plant Families

Important for Pe‘a (29)


  • Sapodilla (Sapotaceae)

  • Myrtle (Myrtaceae)

  • Mulberry (Moraceae)

  • Indian Almond (Combretaceae)

  • Pea (Fabaceae)

  • Soapberry (Sapindaceae)

See Appendix C for a partial list of native and Polynesian plants that could be used for habitat enhancements.








Tropical almond, talie, Terminalia catappa (Photo A. Whistler).




Cover (foraging). Pe‘a vao rely on primary forest for foraging, but will also feed in secondary forest and agroforest.
C

Pe‘a vao are one of two principal pollinators of the native ‘ie‘ie, Freycinetia reineckei. In turn, ‘ie‘ie provides nutrient-rich pollen and famine food for pe‘a vao (27,46) (Photo A. Whistler).



over (roosting).
Pe‘a vao prefer to roost in mature primary forest distant from villages, but occasionally use non-primary forest near roads and houses. Bats have high roost site fidelity, often returning to the same trees, tree, or even specific branches. Roosts are typically located in large trees with exposed branches and edible fruit or flower parts, such as the banyan, asi, and malili (45).


Roost characteristics (45)

Average

Height of roost branch above ground

ca 16-66 ft (5-20 m )

Slope of site

52°

Distance to nearest house

1312-2133 ft (400-650 m)

Cover of valley in fruiting trees

45%





Water. Foods meet water requirements because fruit bats live largely on a liquid diet. Fruit bats “drink” by squeezing fruit between the roof of the mouth and tongue. The juices are swallowed, and pulp is discarded.
Interspersion of habitat components. Suitable roosting habitat that doubles as or is near protected foraging areas is preferable.


Pe‘a vao can be seen soaring above the forest canopy, taking advantage of thermal updrafts and onshore breezes (Photo © Merlin D. Tuttle, Bat Conservation International).






Minimum habitat area. Pe‘a vao require large areas that encompass multiple landowners. For example, home ranges (area a bat normally uses for foraging and roosting) for 2 young male bats radio-tracked in remote primary forest were about 432 and 2021 ac (175 and 818 ha) and core areas were 49 ac (20 ha) (42). Home range varies by habitat type and territories may overlap.
PACIFIC FLYING FOX

American Samoa – Protected Species

I

Species Profile

Pacific flying fox, pe‘a fanua

Photo NRCS file


Scientific name: Pteropus tonganus

Habit: Colonial, nocturnal

Average weight: 463 g (range 314 - 590 g)

Range: Melanesia, Polynesia

Breeding period: Year-round

No. of pups per year: 1

Roosting habitat: Primary and secondary forests

Foraging habitat: Forests, agroforests, and plantations

Food habits: Frugivorous - eats primarily fruit, also nectar, pollen, and leaves

Population estimate: 7000 - 8000 (Tutuila, American Samoa)
NTRODUCTION

The Pacific flying fox or pe´a fanua is the more common and widespread of the two old world fruit bat (Pteropodidae) species in the Samoan archipelago. Pe‘a fanua differs in appearance from pe‘a vao by its darker head and body, golden “cape” around the neck and upper back, and narrower wings. It is most active at night and roosts in colonies. Pe‘a fanua is believed to be is a keystone species, meaning that it strongly influences the structure of forests because of its dominant role in seed dispersal (29).
STATUS & DISTRIBUTION
The species is widely distributed on islands off Papua New Guinea in the west to the Cook Islands in the east (3 subspecies). In American Samoa, pe´a fanua use a wide range of elevations on Tutuila, Aunu‘u, and Manu‘a with the largest numbers on Tutuila. The population for Tutuila is estimated at about 7000-8000 bats, but is uncertain for other islands. The species was able to rebound from being overhunted after hunting was banned in 1992. Overall, the American Samoa population is believed to be stable (19), but in need of ongoing protection from illegal hunting, habitat loss, and hurricanes.
REPRODUCTIVE CYCLE
Pe‘a fanua breed year-round with possible peaks in births in winter and summer (40,46). Females generally bear only one pup per year and dedicate considerable time and energy toward raising young. Pregnancy lasts 5-6 months. Pups fledge (begin to fly) at about 3 months of age when they are 50-75% adult size, but remain dependent on their mothers until about 6 months of age. Mating may overlap with pup-rearing (47). Colonies may be organized by breeding status, and include bachelor groups, harems (females defended by a single male), and females with young (40).
Periods of breeding activity in pe‘a fanua (40,47)

Activity

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Mating

Gest




































Pregnancy





































Pup births





































Pup-rearing





































Pup fledging





































Peak Off-peak
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