Seychelles Sheath-tailed Bat: where and when to see them

The Seychelles sheath-tailed bat is one of the archipelago's most threatened mammals. This small insect-eating bat survives in a few colonies associated with sheltered rock cavities and suitable surrounding feeding habitat. It is quite different from the large fruit bats commonly seen over the islands. Historical declines have left it exceptionally vulnerable to roost disturbance and environmental change, so protecting occupied shelters is more important than obtaining close views.

Size

About 5–6 cm head-and-body length

Weight

About 10–15 g

Lifespan

Not reliably established

Status

Critically Endangered

By day, individuals shelter in communal roosts within protected rock spaces. Around dusk they emerge to pursue flying insects, using echolocation to navigate and locate prey. Their movements link secure roosts with nearby feeding areas, making both parts of the landscape important. Colony attendance and emergence patterns can vary. Sensitive roosts should never be entered or illuminated by visitors, even when bats appear inactive or the entrance seems accessible. Emergence times can vary based on local weather conditions and insect availability, but generally occur shortly after sunset. These bats exhibit high site fidelity, often returning to the same roosts for many years, provided they remain undisturbed. Their social structure involves colonial living, with groups ranging from a few individuals to hundreds sharing a single roost.

• It is the Seychelles' only surviving native insect-eating bat.
• Its common name refers to the arrangement of the tail within the tail membrane.
• A small number of occupied roosts hold much of the remaining population.
• It hunts using echolocation rather than the fruit-finding strategy of flying foxes.

No reliable public viewing season is established for this extremely rare bat. Responsible observation depends on conservation advice and whether a nonsensitive public vantage is available. General island travel conditions should not be interpreted as evidence of seasonal bat abundance or permission to visit roosts. Conservation efforts prioritize minimal disturbance to these critically endangered bats, making any form of public viewing highly restricted. Any potential for observation would be entirely incidental to other activities and subject to strict no-disturbance policies. The focus remains on protecting the species rather than promoting tourism.

Sheltered granite cavities and boulder formations provide roosts, while nearby lowland woodland, clearings and coastal vegetation can support feeding. Suitable airflow and shelter make individual roosts difficult to replace. Loss of feeding habitat or disturbance at a single occupied cavity can affect a substantial colony. These bats are highly particular about their roost sites, often preferring deep, narrow crevices or small caves that offer stable microclimates. The integrity of these specific granite formations is crucial, as they provide necessary protection from predators and environmental extremes. Roost sites are typically found within a few kilometers of foraging grounds, highlighting the importance of conserving the interconnected landscape.

This is an aerial insectivore, catching small flying insects rather than eating fruit or nectar. Available evidence indicates that several insect groups are used. Maintaining healthy insect populations around occupied roosts matters, and broad pesticide use can undermine the feeding environment. They forage in open areas and along forest edges, often making repeated passes to catch insects. Studies suggest their diet includes moths, beetles, and other small dipterans, reflecting the insect diversity of the Seychelles ecosystem. This reliance on a variety of insect prey underscores the need for diverse and healthy invertebrate populations.

Common name

Seychelles Sheath-tailed Bat

Scientific name

Coleura seychellensis

Animal group

Mammals

Size

About 5–6 cm head-and-body length

Weight

About 10–15 g

Lifespan

Not reliably established

Status

Critically Endangered

Identification

It is a small, rapidly flying insectivorous bat with a tail projecting through its tail membrane, unlike the much larger, broad-winged Seychelles flying fox. Its small size and dark coloration make it difficult to distinguish from other small bats in flight, especially in low light. The free-tail characteristic is a key feature when close observation is possible, setting it apart from other local bat species. It is significantly smaller and more agile in flight compared to the fruit bats found in the Seychelles.