Asia boasts 442 bat species, more than a third of the globe’s 1,200 species total. While many of these bats haven’t even been assessed by the IUCN, 7 are known to be Critically Endangered, 15 are Endangered and 44 are Vulnerable.
The bumblebee bat roosts in caves in Thailand and Myanmar
Bats worldwide are understudied and also unloved, partly due to poor public perceptions perpetuated by hundreds of horror movies with their portrayals of bloodsucking bats. The truth is that bats are incredibly beneficial to humans, eating prodigious amounts of insect pests.
One of the most fascinating facts about the bumblebee bat is that its two geographically separated populations in Thailand and Myanmar might currently be undergoing speciation, a process scientist would like to observe.
It’s a hummingbird… it’s a bumblebee… it’s Kitti’s hog-nosed bat. Yes, seriously, look at it: it’s a bat. A teensy, tiny, teeny, weeny bat.
Kitti’s hog-nosed bat (Craseonycteris thonglongyai) is debatably the world’s smallest mammal and most definitely the world’s smallest bat. Informally known as the bumblebee bat, Kitti’s hog-nosed bat is about the size of a large bumblebee, weighing in at just two grams and measuring between 29-33mm about the weight of two Skittles. Again, seriously the miniature size of this mammal is ridicilous. It’s also just one of around 440 bat species found in Asia, a continent that houses more than one third of the world’s 1,200 bat species.
It is an incredibly tiny creature, even smaller than my thumb (though I have small hands already). The weird little-known bat is found only in two countries Thailand and Myanmar.
The bumblebee bat is important for another reason: it’s utterly unique. This single species alone represents an entire family of bats, the Craseonycteridae, which split from the rest some 33 million years ago (Humphery and Bain, 1990; Huston, 2001; Ward, 2004).
Anatomy
The Kitti’s Hog-Nosed Bat has a strange body design to say the least. Many experts have long wondered how it is able to fly with such dimensions. However, it has been determined that they have extra webbing between the hind legs. This webbing helps this species of bat to have control over their movement while in flight (Huston, 2001).
In spite of their small size, the Kitti’s Hog – Nosed Bat have very strong legs and claws. They have toes that curl and that allows them to roost (hanging upside down) with ease. They have a tendon locking mechanism that allows this posture to occur without it consuming very much energy at all.
They use echolocation to help them be able to navigate in their environment. This process involves the use of hearing that is very tuned into their environment. They send out echoes and then wait for the echoes to come back to them. The length of time this takes and the volume of them tells them where the prey happens to be. They are able to create a type of map in their mind about the layout. Incredible if you visualize it, better than night vision if you ask me.
Behaviour
Most species of bats form extremely large colonies. However, the Kitti’s Hog – Nosed Bat doesn’t do so. The largest of their colonies have from 100 to 500 members. Most of them have much less and in some cases, there are only about 10 of them.
Another difference with the Kitti’s Hog – Nosed Bat is their spacing for roosting. They will spread out substantially while all other species of bats move very close to each other. It is believed that this species doesn’t have to rely on the body heat of each other as most species of bats do.
This particular species of bat was only discovered in the early 1970’s and there is still a great deal that we don’t know about them. Experts believe there may be more areas where the Kitti’s Hog – Nosed Bat live but that we haven’t yet identified (Surlykke, 2013).
Reproduction
Mating for the Kitti’s Hog – Nosed Bat takes place as the winter ends. By the spring time the females are ready to have a single youngster. They are extremely small when they are born. They will be attached to the body of the mother around the waist, even when she is out feeding. As they get too large they will start to be left at the roost. It can be several months before their wings are mature enough for them to fly and find their own food.
The Kitti’s Hog – Nosed Bat was a very slow rate or producing new offspring, and this is a serious problem for their future. Experts are trying to find out more about the age where these bats mature, mating rituals, and more so that they can try to get them to reproduce faster in captivity. However, it is hard to study them in the natural environment. With them being so small it is also hard to tell those that are mature for mating and those that are still too young.
Predators
Due to the small size of the Kitti’s Hog – Nosed Bat there are many different predators that they have to try to avoid. This includes birds, snakes, squirrels, and cats.
Downlisted, with caveats
I know what you’re thinking! What are caveats? When a species is downlisted with a caveat it means its population has grown but there is still a great risk affecting the population.
For 12 years, the bumblebee bat was listed as Endangered by the IUCN Red List, but in 2008 it was downlisted to Vulnerable due in part to the discovery of new populations, including ones across the Thai border in Myanmar.
Surveys from 1997-2018 counted around 10,000 bats in 44 caves in western Thailand and five caves in Myanmar. The total population may be considerably higher, however, with researchers estimating the Thai population at around 45,000 individuals in a 2009 study presented in the journal
Endangered Species Research.
No one knows how many might live in Myanmar, since a more thorough survey there could not be conducted due to security issues. But experts believe the Myanmar population is probably quite small due to the bat’s specific microhabitat requirements.
While these new higher population estimates are good news for the planet’s tiniest bat, caveats remain. Scientists believe that the populations in Myanmar and Thailand are not geographically interconnected, with both genetic and echolocation research showing them to be quite different from each other. The two groups may even represent separate subspecies or species. If that is determined to be the case someday, then the new population total would need to be split into two unequal parts.
Scientists believe that the populations in Thailand and Myanmar are undergoing speciation process. This is the process in which one species splits into two or more species. That in itself presents scientists with a fascinating opportunity. But for that to happen, of course, conservationists need to insure neither population vanishes ((Burton and Burton, 2002; Humphery and Bain, 2000; Huston, 2001; Nowak,2006; Stenseth, 2000; Vaughn, et al., 2011).
Threats
This tiny bat is threatened by human disruptions both inside its roosting caves, and in the forests where it forages. Conservationists say that monks using the caves for meditation, drug users escaping to caves for a fix, and tourists driven by the desire to see the bats, have all negatively impacted the species. Indeed, some grottos have been turned into “show caves,” leading to the destruction of bat habitat.
Ecotourism should be fine when tourists do not destroy or modify natural habitat. However, in most cases, when promoting a cave as a tourist attraction guides usually modify the cave to make it more comfortable for the tourists.
If tourists venture into the caves to see the bats, then some impact is unavoidable. The best way to mitigate this damage is to only allow tourists into some big caves where human activities will not change micro-habitat much. The number of tourists allowed into the various caves should also be regulated.
Smoke inside the caves, whether from meditating monks or drug users, could significantly harm the bats. One small piece of good news: in Myanmar, monks have become cave protectors. The monks usually only use the cave entrances, and their presence tends to keep others away, including hunters, drug addicts and even mining companies that would destroy the caves for cement production.
The bat, which was only discovered by scientists in 1974, has also been impacted by scientific collection, and also by their sale as souvenirs to tourists willing to pay for them.
Outside the caves, rapid deforestation due to logging, agricultural expansion and the growth of human communities, remains the major conservation concern, a reality for many vanishing species all across Asia.
The bumblebee bat is legally protected in Thailand, and a portion of its habitat is protected by parks. But much more needs to be done to adequately conserve the species. Conservationists have recommended improved protection and management of its roosting caves as well as broader protection of its foraging areas.
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