| Christmas Island Pipistrelle | |
|---|---|
 | |
| Information | |
| Range | Christmas Island, Australia. |
| Scientific Classification | |
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Mammalia |
| Order | Chiroptera |
| Family | Vespertilionidae |
| Genus | Pipistrellus |
| Species | Pipistrellus murrayi |
| Conservation Status | |
 Extinct | |
The Christmas island pipistrelle (Pipistrellus murrayi) is a species of vesper bat found only on Christmas Island, Australia.
It is a small bat weighing around 3 to 4.5 grams. It has sometimes been considered synonymous with Pipistrellus tenuis however, revisions of the genus based on baculum have identified Pipistrellus murrayi as a distinct species. This is supported by genetic work conducted for the Australian Government as part of its investigation into the decline of Christmas Island ecology and the pipistrelle in mid-2009; the results of this analysis indicate that the Christmas Island Pipistrelle is closely related to but distinct from other Asian pipistrelles. Grave fears are held that the species may now be extinct, with the last individual bat seen in August 2009 with no further sightings despite intensive efforts to locate the species.
Taxonomy and etymology[]
Description[]
Biology[]
Decline and extinction[]
The Christmas Island pipistrelle has declined dramatically in the last two decades. It was once commonly seen throughout the island including in the settlement. It has disappeared from at least 80% of its range and declined more than 90% in abundance since 1994. A reassessment of the number of individuals remaining in January 2009 suggested there may have been as few as 20 individuals left. The only known communal roost contained only four individuals. Three years before there had been 54 individuals in this colony and there were several other known, similar-sized colonies. The long-term monitoring data suggested that, if the rate of decline continued, this species was likely to become extinct around mid-2009. Monitoring in early 2009 showed that some bats survived in the wild, prompting the Australian government to announce on 1 July 2009, that it would attempt to rescue the bat by bringing the last remaining individuals into captivity, with assistance of volunteer bat researchers from the Australasian Bat Society. On 8 September 2009, the Australian Government announced that attempts to capture the bats had failed. A single Christmas Island pipistrelle was observed in August 2009; none have been seen since, and it is feared the species is now extinct.
Cause of Decline[]
The cause of the Christmas Island pipistrelle's decline is unknown. Several potential threats have been suggested: predation or disturbance at roost sites, and disease. Introduced species such as the common wolf snake, giant centipede, yellow crazy ant, black rat or feral cats have all been identified as potential suspects responsible for the decline either through predation or disturbance of the bats. It has also been speculated that an unidentified health threat, or poisoning from the insecticide Fipronil used to control yellow crazy ant 'supercolonies' could be responsible for the decline.