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May 14, 2013

Kitti's Hog-nosed Bat

Kitti's hog-nosed bat, also known as the bumblebee bat, is a vulnerable species of bat and the only extant member of the family Craseonycteridae. It occurs in western Thailand and southeast Burma, where it occupies limestone caves along rivers.

Kitti's hog-nosed bat is the smallest species of bat and arguably the world's smallest mammal. It has a reddish-brown or grey coat, with a distinctive pig-like snout. Colonies range greatly in size, with an average of 100 individuals per cave. The bat feeds during short activity periods in the evening and dawn, foraging around nearby forest areas for insects. Females give birth annually to a single offspring.

Although the bat's status in Burma is not well known, the Thai population is restricted to a single province and may be at risk for extinction. Its potential threats are primarily anthropogenic, and include habitat degradation and the disturbance of roosting sites.

Description


Kitti's hog-nosed bat is about 29 to 33 mm (1.1 to 1.3 in) in length and 2 g (0.071 oz) in mass, hence the common name of "bumblebee bat". It is the smallest species of bat and may be the world's smallest mammal, depending on how size is defined. The main competitors for the title are small shrews; in particular, the Etruscan shrew may be lighter at 1.2 to 2.7 g (0.042 to 0.095 oz) but is longer, measuring 36 to 53 mm (1.4 to 2.1 in) from its head to the base of the tail.

The bat has a distinctive swollen, pig-like snout with thin, vertical nostrils. Its ears are relatively large, while its eyes are small and mostly concealed by fur. Its teeth are typical of an insectivorous bat. The bat's upperparts are reddish-brown or grey, while the underside is generally paler. The wings are relatively large and darker in colour, with long tips that allow the bat to hover. Despite having two caudal vertebrae, Kitti's Hog-nosed Bat has no visible tail. There is a large web of skin between the hind legs (the uropatagium) which may assist in flying and catching insects, although there are no tail bones or calcars to help control it in flight.

Range and distribution


Kitti's hog-nosed bat occupies the limestone caves along rivers, within dry evergreen or deciduous forests. In Thailand, Kitti's hog-nosed bat is restricted to a small region of the Tenasserim Hills in Sai Yok District, Kanchanaburi Province, within the drainage basin of the Khwae Noi River. While the Sai Yok National Park in the Dawna Hills contains much of the bat's range, some Thai populations occur outside the park and are therefore unprotected.

Since the 2001 discovery of a single individual in Burma, at least nine separate sites have been identified in the limestone outcrops of the Dawna and Karen Hills outside the Thanlwin, Ataran, and Gyaing Rivers of Kayin and Mon States. The Thai and Burmese populations are morphologically identical, but their echolocation calls are distinct. It is not known whether the two populations are reproductively isolated.

Behaviour


Kitti's hog-nosed bat roosts in the caves of limestone hills, far from the entrance. While many caves contain only 10 to 15 individuals, the average group size is 100, with a maximum of about 500. Individuals roost high on walls or roof domes, far apart from each other. Bats also undertake seasonal migration between caves.

Kitti's hog-nosed bat has a brief activity period, leaving its roost for only 30 minutes in the evening and 20 minutes at dawn. These short flights are easily interrupted by heavy rain or cold temperatures. During this period, the bat forages within fields of cassava and kapok or around the tops of bamboo clumps and teak trees, within one kilometre of the roosting site. The wings seem to be shaped for hovering flight, and the gut contents of specimens include spiders and insects that are presumably gleaned off foliage. Nevertheless, most prey is probably caught in flight. Main staples of the bat's diet include small flies (Chloropidae, Agromyzidae, and Anthomyiidae), hymenopterans, and psocopterans.

Late in the dry season (around April) of each year, females give birth to a single offspring. During feeding periods, the young either stays in the roost or remains attached to the mother at one of her two vestigial pubic nipples.

Conservation 


As of the species' most recent review in 2008, Kitti's hog-nosed bat is listed by the IUCN as vulnerable, with a downward population trend.

Soon after the bat's discovery in the 1970s, some roosting sites became disturbed as a result of tourism, scientific collection, and even the collection and sale of individuals as souvenirs. However, these pressures may not have had a significant effect on the species as a whole, since many small colonies exist in hard-to-access locations, and only a few major caves were disturbed. Another potential risk is the activity of local monks, who have occupied roost caves during periods of meditation.

Currently, the most significant and long-term threat to the Thai population could be the annual burning of forest areas, which is most prevalent during the bat's breeding season. In addition, the proposed construction of a pipeline from Burma to Thailand may have a negative impact. Threats to the Burmese population are not well known.

In 2007, Kitti's hog-nosed bat was identified by the Evolutionarily Distinct and Globally Endangered (EDGE) project as one of its Top 10 "focal species".

Slender loris

The slender lorises (Loris) are a genus of loris native to India and Sri Lanka. Its local name is "Kutti thevangu". There are two known species:

  • The red slender loris, Loris tardigradus
  • The gray slender loris, Loris lydekkerianus
Some sources list only one species, Loris tardigradus and regard subspecies of lydekkerianus as subspecies instead of tardigradus.

The slender loris is a species of primate in the family Loridae. It is found in India and Sri Lanka. Its natural habitats are subtropical or tropical dry forests and subtropical or tropical moist lowland forests. It is threatened by habitat loss. The species used to be considered as Loris tardigradus lydekkerianus but Loris tardigradus is now a separate species found in Sri Lanka. This species has been divided into several geographically separated subspecies.

Physical description


This small, slender primate is distinguished by large forward-facing eyes used for precise depth perception, long slender limbs, a well-developed index finger, the absence of tail, and large prominent ears, which are thin, rounded and hairless at the edges. The soft dense fur is reddish-brown color on the back, and the underside is whitish-grey with a sprinkling of silver hair. Its body length on average is 7–10 in (180–250 mm), with an average weight of a mere 3–13 oz (85–370 g). This loris has a four-way grip on each foot. The big toe opposes the other 4 toes for a pincer-like grip on branches and food. It has a dark face mask with central pale stripe, much like the slow lorises.

Behavior 


The red slender loris favors lowland rainforests (up to 700 m in altitude), tropical rainforests and inter-monsoon forests of the south western wet-zone of Sri Lanka. Masmullah Proposed Forest Reserve harbors one of few remaining red slender loris populations, and is considered a biodiversity hotspot. The most common plant species eaten was Humboldtia laurifolia, occurring at 676 trees/ha, with overall density at 1077 trees/ha. Humboldtia laurifolia is vulnerable and has a mutualistic relationship with ants, providing abundant food for lorises.[5] Reports from the 1960s suggest that it once also occurred in the coastal zone, however it is now thought to be extinct there.

The red slender loris differ from its close relative the gray slender loris in its frequent use of rapid arboreal locomotion. It forms small social groups, containing adults of both sexes as well as young animals. This species is among the most social of the nocturnal primates. During daylight hours the animals sleep in groups in branch tangles, or curled up on a branch with their heads between their legs. The groups also undertake mutual grooming and play at wrestling. The adults typically hunt separately during the night. They are primarily insectivorous but also eat bird eggs, berries, leaves, buds and occasionally invertebrates as well as geckos and lizards. To maximize protein and nutrient uptake they consume every part of their prey, including the scales and bones. They make nests out of leaves or find hollows of trees or a similar secure place to live in.

Reproduction 


Females are dominant. The female reaches her sexual maturity at 10 months and is receptive to the male twice a year. This species mates while hanging upside down from branches; individuals in captivity will not breed if no suitable branch is available. The gestation period is 166–169 days after which the female will bear 1–2 young which feed from her for 6–7 months. The lifespan of this species is believed to be around 15–18 years in the wild.

Threats


This slender loris is an endangered species. Habitat destruction is a major threat. It is widely trapped and killed for use in supposed remedies for eye diseases and get killed by snakes, dogs, and some fish. Other threats include: electrocution on live wires, road accidents and the pet trade.

Conservation 


The red slender loris was identified as one of the top-10 "focal species" in 2007 by the Evolutionarily Distinct and Globally Endangered (EDGE) project.

One early success has been the rediscovery of the virtually unknown Horton Plains slender loris (Loris tardigradus nycticeboides). Originally documented in 1937, there have only been four known encounters in the past 72 years, and for more than 60 years until 2002 the sub-species had been believed to be extinct. The sub-species was rediscovered in 2002 by a team led by Anna Nekaris in Horton Plains National Park. The late 2009 capture by a team working under the Zoological Society of London's EDGE programme has resulted in the first detailed physical examination of the Horton Plains sub-species and the first-ever photographs of it. The limited available evidence suggests there may be only about 100 animals still existing, which would make it among the top five most-threatened primates worldwide.

Miyakejima Island Wedding


One may be tempted to believe that this picture comes from some post-apocalyptic movie, but fact can sometimes be stranger than fiction. Miyakejima Island lies on an active volcanic chain in the Izu Islands and it has one of the highest concentrations of poisonous gasses (mostly sulphur) in the world. After a series of eruptions in 2000, these levels became so high that mass evacuations were instituted and flights were cancelled over the area for many years. In 2005, the residents of Miyakejima Island were allowed to return to their homes but to this day they are required to carry their gas masks with them at all times.

Intersections Without Traffic Lights

Intersections Without Traffic Lights
A postmodern look at idealistic major city intersections that work without traffic lights, and thus without stopping. Ramps remove the need for stop signs or traffic lights.