|
|
|||
|
|
|||
| นิตยสาร สารคดี: ฉบับที่ ๒๒๑ เดือนกรกฎาคม ๒๕๔๖ | ISSN 0857-1538 | |||
|
|
|
| Story: Wiwat Pandawutiyanon Photos: Boonkit Suthiyananon | |||
|
|||
 |
|
They wait on the ground for an unknowing trekker or mammal to pass by. With their heads hanging high in the air, they are ready to launch themselves onto their prey and locate a soft spot to dig their three jaws into. There is no letting go of the prey until they are bloated with blood. They are land leeches, the squishy blood suckers of tropical forests. To many, leeches invariably add excitement and anxiety to an otherwise peaceful walk through the forest. Some may wonder how they are able to attach themselves to fast moving fearful hikers. Others, especially those hoping to avoid them, might be curious about where they live and when they come out from their hiding places. But to Thongchai Ngamprasertwong, a young researcher at Chulalongkorn University, the land leech is the research topic of choice, a study area that has so far been (understandably) left largely unexplored in Thailand. |
|
 |
Though he does not dislike them, Thongchai did not choose to study leeches out of his affection for them. Rather he seeks to answer several important unanswered questions regarding diversity, distribution, habitats and the effects of physical factors on population of terrestrial leeches. To understand diversity, distribution and habitats of leeches-Thongchai travels all over Thailand to collect samples. To determine the factors that influence leech population and life cycle, however, requires a more in depth research involving many trips to Khao Yai National Park to count leeches 5 times a day and closely observe their routines from feeding to mating. |
||
 |
Taxonomically speaking, leeches belong to the Haemadipsidae family, literally meaning "blood thirsty." Leeches have two suckers at both ends of the body and use them to move about by "looping." A leech's movement always seems quicker than expected, but when it comes to drawing blood, it takes time to choose a good soft spot and bury its jaws. Once it starts sucking , there is no stopping. A leech will suck for up to an hour until it has grown several times the original size and can barely move. A leech with a full stomach can survive up to 6 months before another meal. Thongchai's research not only brings him merit (for regularly donating blood to his subjects) but has also led to important discoveries. To date, he has found several new species of land leeches and a whole new genus of leeches in Thailand. |