Little yellow-shouldered bat  (Sturnira lilium)

The little yellow-shouldered bat is classified as Least Concern (LC) on the IUCN Red List (1).

Named for the conspicuous deep yellow shoulder patches that are most pronounced on large adult males, the little yellow-shouldered bat (Sturnira lilium) is a common species of Central and South America (2) (3). This medium-sized bat has short ears, a small, broad, spear-shaped nose-leaf, a blunt muzzle and a rounded forehead (2). Its tail membrane is greatly reduced compared to other bats in the family Phyllostomidae (2) (3).

The little yellow-shouldered bat has short, velvety fur, which is highly variable in colour, being orange-brown, grey, or bright orange on the upperparts and paler on the underparts. The shoulder patches on the adult male are also variable in colour, often having a reddish tinge to the hairs. The wing membranes are black (2) (3).

One of the most abundant and widespread bats in the family Phyllostomidae, the little yellow-shouldered bat is found throughout Mexico, southwards through Central America and into eastern South America, as far south as Argentina. It also occupies the Lesser Antilles of the Caribbean, but is absent from higher altitudes on the west coast of South America (1).

The little yellow-shouldered bat occupies a variety of habitats, from rainforest to dry and mountain forest, although it tends to prefer moist habitats (1) (3). It is found up to elevations of around 2,600 metres (3).

Using echolocation to find its food, the little yellow-shouldered bat feeds on a variety of different fruits (1) (2) (4), as well as pollen, nectar and insects (2) (5). It typically forages in trees but occasionally searches for fallen fruits on the forest floor (3). The little yellow-shouldered bat is an efficient disperser of seeds and an important pollinator of plants, meaning this species is vital for forest growth (1).

A gregarious species, groups of the little yellow-shouldered bat roost in the cavities of large trees, within vine tangles, among palm leaves and in caves (2) (3). There are two breeding seasons a year, which are both concentrated between the warm-rainy season and the beginning of the dry season, with births peaking between February and March and between June and July in Costa Rica (1) (2). The male has a scent gland on both shoulders that may be used in courtship. Like other bats in the genus Sturnira, the little yellow-shouldered bat probably gives birth to a single pup each year (4).

There are no known major threats to the little yellow-shouldered bat, and its populations are described as both abundant and stable (1).

Although there are currently no known conservation measures targeting the little yellow-shouldered bat, it is found in all of the protected areas of Central America where there is suitable habitat (1).

ARKive is supported by OTEP, a joint programme of funding from the UK FCO and DFID which provides support to address priority environmental issues in the Overseas Territories, and Defra

For more information on bat conservation:

• Bat Conservation International:
  http://batcon.org/
• The Bat Conservation Trust:
  http://www.bats.org.uk/
• The IUCN/SSC Bat Specialist Group:
  http://www.batconservancy.org/chiroptera-specialist-group-bat-conservation.php