Rodrigues Fruit Bat (Pteropus rodricensis) Fact Sheet: Behavior & Ecology

• Crepuscular (most active at dawn and dusk); nocturnal
• At dusk fly to fruit trees to feed.
  • Foraging areas well removed from roosts
• Roost on higher trees that rise above forest canopy
  • During daylight bats typically move about the roost site
  • Males actively defend roosting territory
  • Females may associate with different bats when roosting than when foraging
• For maintaining body temperature, don't use torpor ("temporary hibernation") as do small microchiropterans (McNab & Armstrong 2001)
  • To keep warm, wrap wings around body and tuck in head
  • To keep cool, fan wings gently, pant

• Home range very limited; less than 1,000 km² (386 mi²)
• Dominant males hold a roosting territory and a separate feeding territory.

General

• Strongly colonial and gregarious; crowding together in roosting tree is a favored strategy (Pierson and Rainey 1992) (West & Redshaw 1987)
• Males defend harems of up to 8 females.

Hierarchy

• Dominant males control a group of females
• Subordinate males roost together separately

Displays

•  Males thrust thumb with claw towards opponent's head in aggressive display

Vocalization

• Both sexes vocalize during mating
• Vocalization frequent during aggressive interaction.

Olfaction/Scent Marking

• Males may mark a tree with chin and neck glands during mating season. (Kulzer 1990)
• Males in managed care make perches or walls with nick and chin glands (Carroll 1979)
• In males of many Pteropus species studied, glands on the back of the neck excrete sticky substance that mats the hair in mating season (Kulzer 1990)

• "Wing shake" used by adult males, females, juveniles (Carroll 1979)
  • One or both wings thrust forward folded to position the thumb claw in front
  • Wings shaken with claw aimed toward the opponent's head while emitting harsh vocalization
• Males and females in managed care show aggression towards intruders in their territory (Carroll 1979)

• Adult males defend small territory 
  • Foraging areas defended by individual males
  • Males also actively defend roosting territory
• Males may mark tree branches with scents from glands on chin and neck. (Kuzel 1990)

Play (Carroll 1979)

• "Play chase" by immature bats flying to one location and rapidly leaving
• "Play wrestle" involves close belly contact between individuals, with restrained biting on the neck
  • A pair of bats, or even a group may wrestle together
  • Adult females often; adult males rarely
• Sometimes chase and wrestle alternate in long play sessions

(Carroll 1979)

• Not strong flyers but can take off from ground
• In a study of impacts with Australian airlines several flying foxes flew at elevations around 150 m (492 ft) (Parsons et al 2008)
  • Occasionally up to 1,500 m (4,921 ft)
• Observations from a colony under managed care at Jersey Preservation Trust
  • Moving with left hindlimb, right forelimb, right hindlimb, left forelimb; thumb claw helps front limb grasp
  • Faster moving with diagonally opposite limbs moving together (used by males defending territory)
• Occasionally flap wings in place, holding onto branch with feet; common in infants and juvenile
• Resting postures:
  • Most common when resting - one or both feet grasp perch, bat hangs head down; wings fold around body
  • When awake and alert, wings fold to sides, with belly fur visible

• Serve as vital pollinators and seed dispersers (Cox et al 1991, Cox & Elmqvist 1992)
  • Like other Pteropus species, are the only native animals or one of few that pollinate and disperse seeds
  • Diversity of island flora depends P. rodricensis
  • Without these "strong interactors" a "cascade of linked plant extinctions" may result
• Rodrigues in historic past had many more species of animals:
  • Up to 14 endemic bird species; nearby Mauritius also supported now-extinct dodo (Raphus cucullatus). (Carroll 1981)
  • Extinct birds included the large flightless Solitare, two owl species, two parrots, a rail, a flightless heron
  • Extinct reptiles included 2 or 3 giant tortoise species (over 20,000 removed from Rodrigues between 1759 and 1761)

A typical resting posture of the Rodrigues fruit bat.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

AZA (2000)
Carroll (1979, 1981)
Cox et al. (1991)
Cox & Elmqvist (1992)
Crichton & Krutzsch (2000)
Kulzer (1990)
Nowak (1999)