Black Eared Flying Fox

The black-eared flying fox (Pteropus melanotus) is generally found in forests and swamps on small, oceanic islands, such as the Andaman and Nicobar Islands of India (Bompuka, Car Nicobar, Great Nicobar (including Campbell Bay), Kamorta, Katchal, Kondul, Nancowrie, South Sentinel, Tilangchong, Tressa and Trinket Islands [Pteropus melanotus melanotus] and South Andaman and Rutlans Islands [P.m. tytleri]) (4), the Mentawi Islands (Nias and Enggano [P. m. modiglianii]) of Indonesia, and Christmas Island of Australia (P.m. natalis). The population on the island of Enggano was extirpated after a severe typhoon (5). It has been recorded form sea level to an elevation of 1,000 m asl. The type locality is the Nicobar Islands.

The bat has dark brown to black fur, except for light brown fur in the chest and neck region. The male is larger than the female.

In South Asia, the bat roosts in large colonies comprising several thousands of individuals in rainforest trees in the mangrove vegetation (4). On Christmas Island, part of the population roosts in large camps at traditional locations and part roosts scattered singly and in small groups through the forest. It was recorded roosting in 11 tree species in December 2005-Feb 2006 (8). Camps are near the coast and numbers in camps fluctuate widely, possibly due to winds that aid emergence (9). The bat is relatively diurnal, emerging from camps well before dusk. It uses its keen vision in low light to navigate. It also uses olfaction to find fruits and communicate reproductive status.

It eats wild and cultivated fruit, blossoms and flowers, such as Bombax, Muntingia calabura and Sterculia (7). It helps to disperse fruit tree seeds and fertilize areas around roost trees. Domestic cats are the main predators of the bat on Christmas Island, making up 21% of their diet by weight. Humans also eat fruit bats. Occasional predators include birds of prey and arboreal snakes. The bats avoid predation mainly through communal roosting in tall trees.

In many related species, males form mating harems during temporary breeding aggregations. In P. melanotus, breeding occurs once a year and February tends to be the peak birthing time. One young is born (6), with non-flying young recorded in December and January (8,9). Females nurse and care for their young until they reach independence. In most Pteropus species, females carry their young for the first few weeks after birth, then they leave the young in a roost while foraging, returning to nurse them. Pteropus young generally become independent 2-3 months after birth. The bat reaches sexual maturity in 6 months; other Pteropus species generally reach sexual maturity in 18-24 months. Related species live 25-35 years.

The Conservaton Status is Vulnerable (1) as the species is thought likely to undergo a decline of more than 30% over the next 3 generations due to the impacts of habitat loss, hunting and possibly introduced predators. If the Christmas Island population is specifically distinct, it would be assessed as Critically Endangered as its population declined by 83% in 3 generations; the causes of the decline are not known and may not have ceased. P. melanotus was placed on low risk or least concern on the IUCN Red List. Natives hunt a limited number. There are concerns that the bat is especially vulnerable due to its restriction to small, oceanic islands and its apparent lack of fear of humans. It also tends to be active by day, making it easier to hunt than related species. Aul and Vijaykumar (7) reported a colony of more than 300 individuals in a mangrove creek on Great Nicobar Island. They also counted over 500 individuals in the mangroves and under Nypa palms on Tillangchong Island in the Nicobars; 10-15 individuals were recorded from palm fronds on Tillangchong Island, with several pups in this colony in March. On Christmas Island in 1984 the population was estimated to contain 3,500 individuals in 5 main camps and 2,500 scattered singly or in small groups (10). The camps were thought to be historical, dating to before human settlement. By 1989 one more camp had been located, bringing the total to 6 camps, with only 100 or so extra animals (11). Duncan et al. (12) interpreted Tidemann's population figures as below 10,000 animals. In 1997-1998, few camps were and these contained few individuals (13). In August 2002, 17 Individuals were recorded during 26 field days of a general fauna survey and the population was loosely estimated to be 500-1,000 individuals (14). In April 2004 only one of the original 5 known camps was found and in November 2004 that camp had 299 individuals (9). In December 2005, 2 of the 6 colonies once known were active but extensive searches for additional colonies were not successful. Counts in these 2 colonies from January-March 2006 varied from 14-500 individuals, apparently in response to local wind conditions. The number of bats roosting away from camps is probably lower than the number in camps; nocturnal surveys reveal wide distribution of foraging animals. The entire population was unlikely to number more than 1,000 individuals in March 2006 (8,9). In September 2006, 1,381 individuals were counted on Christmas Island (15). The population is decreasing. In the Andaman and Nicobar Islands, the bat is threatened by deforestation, generally resulting from logging operations and converting land to agricultural purposes. It is also threatened due to tourism related developmental activities (4) and from overhunting at daytime roosts, as the bones are crushed and used as asthma medicine (5). The bats are kept as pets on Car Nicobar, Kamorta, Katchal, Pulo Milo and Trinket Islands. The December 2004 tsunami probably damaged the mangrove habitat of the species. The population on the Indonesian island of Enggano may have been wiped out by a hurricane. Threats to the bat on Nias probably include general habitat loss. It is preyed on by feral cats on Christmas Island, where there has been some hunting, but there is no recent evidence of hunting in this part of the species range (9). Corbett et al. (14) hypothesised that a severe cyclone in 1988 initiated the decline in the Christmas Island population, but other anecdotal evidence indicates that the decline began in the mid 1990s (8). The yellow crazy ant has caused general ecological breakdown on Christmas Island since the late 1990s (16). Disease may be a factor. Threats to the Christmas Island population are likely to be a combination of factors (8). James et al. (15) detail possible threats to the species including predation or disturbance by introduced and/or native species; predation and/or persecution by humans (mostly formerly); habitat loss; storm events; accidental poisoning; light pollution, disease and parasites. The bat is listed on Appendix II of CITES., but is categorised as vermin under the Indian Wildlife (Protection) Act. There is a need to encourage the protection of the globally important Andaman and Nicobar Islands population. It occurs in the Campbell Bay protected area on Great Nicobar. On Christmas Island a National Park covers 63% of the island and invasive species must be controlled. The bats are important members of their native ecosystems, especially for dispersing tree seeds. C.R. Tidemann said the bat is an easy prey for hunters on Christmas Island: (1) it shows a diurnal shift from the usually noctural habits of congenerics; (2) it tends to feed near the ground, particularly in the exotic shrub of Muntingia calabura; (3) it shows a failure to respond in an appropriate manner to the approach of potential predators; on Christmas Island it has no predators other than man.