Lesser Dawn Bat (Eonycteris spelaea)
Common Names: Lesser Dawn Bat, Dobson's Long-Tongued Fruit
Bat, Cave Fruit Bat, Cave-dwelling Blossom Bat
HB: 80-100; T:15-20; FA: 60-75; E: 18-24; HF: 20-24; W;37-82g
The fur is short and thin, with the upperparts dark to light brown and the underparts greyish; the head is darker, with a more thinly haired area at the back of the neck which is often tinged yellow. Males on average are larger than females, and adult males have a well marked ruff on the sides of the neck, which is darker than the back and chest. On each side of the anal orifice is a small kidney shaped subcutaneous gland, the function is yet unknown. The mandible is modified for nectar eating, with the front portion formed into a spout shaped depression. Tate (1942b) says this is for the attachment of the greatly developed muscles whose contraction causes the tongue to protrude. The first lower incisor as a shallow groove on the occlusal surface. The canines are long, strong, well separated and grooved on the front. The first premolars are quite small, with the second premolars dominant and the following teeth progressively lower crowned. The last molars are very small, and the lower ones may be absent.
This species ranges widely from Northern South Asia, into
Southern China, and much of Southeast Asia. In South Asia it is known from India
(Andaman and Nicobar Islands, Andhra Pradesh, Assam, Karnataka, Manipur,
Meghalaya, Mizoram, Nagaland, Sikkim, Tamil Nadu (Vanitharani et al. 2005) and
Uttaranchal) and Nepal (Far Western Nepal) (Molur et al. 2002). In China it is
found in south-western Guangxi and Yunnan (Smith and Xie 2008). In mainland
Southeast Asia, it ranges from Myanmar in the west, through Thailand, Lao
PDR, and parts of Vietnam and Cambodia to Peninsular Malaysia. In insular
Southeast Asia, it ranges from Indonesia (Sumatra, Java, Bali, Lombok, Sumba,
Sulawesi, Muna, Sanana, Halmahera, Batjan and Tidore), much of the island of
Borneo (Brunei, Indonesia and Malaysia), the island of Timor (East Timor and
Indonesia) to the Philippines where is found throughout the country, except the
Batanes/Babuyan region. It has been recorded from Biliran, Bohol, Camotes
(Paguntalan pers. comm. 2006), Carabro (Alcala and Alviola 1970), Catanduanes,
Cebu, Danjugan (Carino 2004), Ilin (Gonzalez pers. comm. 2006), Leyte, Luzon
(Abra, Cavite, Ilocos Norte, Laguna, Pampanga, Rizal, and Sorsogon provinces),
Marinduque, Maripipi, Masbate, Mindanao (Agusan del Norte, Davao del Sur, Davao
Oriental, Lanao del Norte, Misamis Oriental, Misamis Occidental [Ramayla pers.
comm.], South Cotabato, Surigao del Norte, and Zamboanga del Sur provinces),
Mindoro, Negros, Palawan, Polillo, Samar (Gonzalez pers. comm. 2006),
Sanga-sanga, Sabtang, Siargao, Sibuyan, Siquijor, Tablas, and Ticao (Paguntalan
pers. comm. 2006, Heaney et al. 1998). It occurs from sea level to 1,000 m asl.
Brunei Darussalam; Cambodia; China; India (Andaman Is., Andhra Pradesh, Assam, Karnataka, Manipur, Meghalaya, Nagaland, Nicobar Is., Sikkim, Tamil Nadu, Uttaranchal); Indonesia; Lao People's Democratic Republic; Malaysia; Myanmar; Philippines; Singapore; Thailand; Timor-Leste; Vietnam
More than 4,000 individuals were recorded from Batu
caves in Malaysia (Bates and Harrison 1997). The abundance, population size and
trends for this species are not known in South Asia although a recent discovery
of this species in Kalakkad-Mundanthurai Tiger Reserve in Tamil Nadu suggests a
comparatively rare occurrence compared to the Rousettus leschenaulti
(Vanitharani et al. 2005). In the Philippines, this species is often found in
colonies of thousands in caves, even in agricultural areas (Heaney et al. 1989;
Heideman and Heaney 1989; Lepiten 1995; Rickart et al. 1993). On Palawan Island
two populations were found, one exceeding 2,000 individuals and another that
probably exceeded 50,000 individuals (Esselstyn et al. 2004).
Population Trend: Unknown
The Dawn Bat is a small Southeast Asian rainforest bat which
lives in the mangrove and lowland forests of Malaysia, Indonesia and Borneo. Its
unique and special place in the rainforest ecosystem has only been recently
discovered. This is a cave roosting bat forming compact clusters and cohabits
with other bats. It roosts in large groups consisting of thousands of
individuals in caves in forested areas. They are more often found in disturbed
and agricultural areas, although they do occur in primary forest as well. It is
a nectar eating bat with a slow flight, and has adapted to using the flowers of
many important agricultural and orchard crops (Smith and Xie 2008). It has
been also reported living in small groups from the attics of village huts in
northeast India (Tarapada Bhattacharyya pers. comm. June 2005) and Myanmar (Khim
Maung Swe pers. comm. January 2000).
Systems: Terrestrial Dawn Bats have long and slender snouts which give them a dog-like appearance. Their ears are small and pointed and their eyes are round and small. The fur on the dawn bat's back is dark brown and lighter on their underside. Males have a ruff, or fur collar around their neck, which is a little darker in colour then their head
and chest hair. Females only have sparse hairs around their necks. The tongue of a Dawn Bat is long and can be thrust forward into flowers, while brush-like projections allow it to pick up pollen and nectar.
The male dawn bat is larger than the female. They weigh from 55 to 82 grams while females weigh 35 to 78 grams. Dawn Bats are 8.5 to 12.5 cm long from head to tail. They either have a very small tail or none at all. Their forearm length is 6 to 8 cm long. The genus Eonycteris doesn't have a claw on their index finger like most other bats.
Female Dawn Bats reach sexual maturity after one year while males become sexually mature in two years. Females can have babies at any time of the year. Gestation is a little longer than 6 months, sometimes as long as 200 days. Usually one pup is born at a time. It attaches itself to a nipple and holds on for 4 to 6 weeks. After that time it starts to take little practice flights of its own. They aren't completely weaned until after 3 months.
Dawn Bats roost in limestone caves found in Malaysia and the Indonesian archipelago. Small groups of several dozen will roost in small shelters, while tens of thousands can inhabit larger caves. Dawn Bats are nocturnal and emerge from their caves at dusk to feed on pollen and nectar of night blooming plants. Their favourite flowers are from the Mangrove Apple (Sonneratia alba)and the Durian (Durio zibethinus). The flowers of the durian tree are large and waxy and only bloom at night. As the Dawn Bat hangs onto the flower and pushes its nose deep inside to lick the nectar, pollen covers its face and chest. They are the main pollinators of these two trees and very important to their survival.
Peaches, bananas, avocados, kapok, hemp and latex are some other plants which depend on bats for pollination. In Southeast Asia some of the largest caves with bat colonies are being destroyed by limestone quarrying. Mangrove swamps, home to the Mangrove Apple, are being filled in for development, destroying one of the Dawn Bat's main food supplies. Bats have been accused of spreading disease and destroying commercial fruit crops. However, Dawn Bats prefer ripe and strong-smelling fruit. Commercial fruit is picked green for shipping and is therefore rarely damaged by these bats.
Very little is known about the importance of bats and how forests depend on them for their survival. But it is known that they are one of the main pollinators and seed dispersers for many tropical plants. Bats often make up more than half of the mammal species in a rainforest ecosystem and most species of bats have not been studied.
Although Dawn Bats are being killed by the thousands, they are not on the CITES or IUCN list as a vulnerable or protected species. Malaysia has a Wildlife Protection Ordinance (Amendment 76). However, Dawn Bats can be killed if they pose a threat to crops or property. Since many still think they are fruit pests, the ordinance does little to protect them. People need to become more educated about the Dawn Bat to understand how important they and other bats are to the forests and crops.
There are no major threats to this species as a whole. In
parts of South Asia it is locally threatened by deforestation, generally
resulting from logging operations and the conversion of land to agricultural and
other uses (Molur et al. 2002). Cave tourism and lighting is an emerging threat
in some caves, as at Borra Caves, Andhra Pradesh (Srinivasulu and Srinivasulu
2003). In China they are often under heavy hunting pressure (Smith and Xie
This species is adaptable, and is present in many protected areas throughout its range. No direct conservation measures are currently needed for the species as a whole. In South Asia, this species like most other fruit bats in India is considered a vermin under Schedule V of the Indian Wildlife (Protection) Act. The species has been recorded from protected areas like Kalakkad-Mundunthurai Tiger Reserve in Tamil Nadu (Vanitharani et al. 2005). Populations of this species should be monitored to record changes in abundance and distribution, and lobbying to remove it from vermin category are recommended (Molur et al. 2002). Awareness programmes on ill effects of cave/roost disturbance is recommended (C. Srinivasulu and Bhargavi Srinivasulu pers. comm. September, 2007).