Protect against bites by land leeches

[teotp]

Many BC members and jungle trackers experienced the bites of leeches during their trips to Malaysian rainforest. It is difficult to avoid being bitten by these blood-sucking creatures even wearing leech-socks, spraying footwear and leggings with insecticide like "Baygon" or generously applying legs with "Tiger Balm" (Ismail & Ghazally, 2010).

Laboratory and field tests carried out by FRIM* on a collaborative study with Mosi-Guard International & Germax (Malaysia) tested on the Citriodiol TM and proved to be an excellent repellent against leeches. Heavy and moderate spray on footwear and trouser legs (tucked into socks) gave complete protection against bites by two species of leeches (Haemadipsa picta and Haemadipsa sylvestris). The repellency of "Mosi-Guard" persists over a six-hour period in the field without any decline in its effectiveness (Kirton, 2004).

Sharing the above information with BC members and jungle trackers from overseas.

Teo T P

*FRIM = Forest Research Institute Malaysia.

References:

Laurence Kirton, 2004. Leech protection - fight them off with fragrance. FRIM IN FOCUS: April-May-June Issue, page 11.

Ismail G., & S. Ghazally, 2010. The Malaysian Rainforest Realm - Facsinating Facts in Q & A.

[Silverstreak]

Thank you Thiam Peng for the infor!:)

This is the insect repellent spray Mossie Guard (http://www.mosiguard.com/)

Has anyone seen this in the Singapore market ?

LC, have you seen this in KL?

http://i35.photobucket.com/albums/d156/Schir/Bin/SNAG_Program-0000-1.jpg

[teotp]

You are welcome Sunny.

I was looking for it in pharmacies like Guardian, Unity..near to my place but they are not carry it for sale. I will look for it again when I go to other shopping complex.

Teo T P

Watsons Pharmacy (Changi Airport T3) : Not available.

[Glorious Begum]

LC, have you seen this in KL?



I have been using this for many years. You can get this in any pharmacy shop in Malaysia. Not cheap though, for spray bottle is around MYR28.

Watch this video taken in Taman Negara trip. Sorry for poor quality shot.

Sprayed on your shoes and leeches would not crawl up to you.

http://www.youtube.com/watch?v=DiHwo_rIzF0

[Silverstreak]

And if all fails and one got attached to you .......

Thanks to LC for passing this on during our previous trip up north:

To stop the bleeding tobacco tops every other known remedy in stopping the bleed.

Take a pinch of tobacco, cover over the wound and stick over with a plaster. The bleed will stop in no time.

:cheers:

[Glorious Begum]

:bsmile: For non-smoker, you can try using Melastoma malabathricum.

Crush the leaves and drip the juice on the bite. :cheers:

[teotp]

Thank you LC for the information of where to get the "Mosi-guard" and the methods to stop bleeding after leech bite.

I did a survey about mosquito repellents in few local pharmacies like Watsons, Guardian, Unity, Cold Storage.. there is a mosquito spray repellent manufactured by "Tiger Balm" contains "Citronella oil". I was wondering whether this is the same as "Citriodiol"? If yes, can this repellent subsititues the "Mosi-guard"?

Teo T P

Additional information:
"Tiger Balm" mosquito repellent (spray): active ingredients are citronella oil 9%, camphor 3% and menthol 1%.
Another mosquito repellent "Moz-away (spray)": active ingredient is citronella 15% w/v.

[MrGee]

According to the Mosi-Guard website (http://www.mosiguard.com.au/whatismosiguard.htm), Citriodiol is more effective than and longer lasting than Citronella.

We provide guided jungle treks here at Rainbow Lodge and I would love to find a supplier of Mosi-Guard. We have never seen it for sale here in Cambodia. The nearest distributor appears to be in Malaysia.

We currently use OFF! Active, which is certainly helpful. Leeches tend not to bite where it is applied but they will continue up to places where it isn't, sometimes with unpleasant results! OFF! contains DEET, which we do not really want to use (even at only 15%). Also, although the "Active" version is sweat resistant, it doesn't stay on for long in the rain or when walking through puddles or mountain streams. Having said that, I don't suppose Mosi-Guard would either.

[teotp]

N,N-Diethyl-m-toluamide (DEET) has been used as a repellent against blood-sucking insects like mosquitoes all over the world. However, DEET has many disadvantages such as unpleasant odour and skin penetration. Further more, it reacts with certain plastics and synthetic rubber and also carcinogenic (Nishimura & Satoh, 1999).

Both citronella oil and "Mosi-guard"(= Citriodiol) are essential oils. Citriodiol is a biological active natural product distilled from Eucalyptus citriodora, which tested with no or very low toxicity to human (Guenther, 1956; Nishimura & Satoh, 1999; Bruneton, 1999; Lewis, 2007). The chemicals analysed from Eucalyptus citriodora oil gave rise to p-menthane-3,8-diols (cis type 1 and trans type 2). Research works by Nishimura & Satoh (1999) on mosquitoes like Aedes albopictus and Aedes aegypti (Yellow fever mosquito) using essential oils extracted from E. globulus, E. radiata, E, citriodora, E. camaldulensis as repellents in comparison to DEET, both E. citriodora and E. camaldulensis showed excellent repelling activities and are superior to DEET. Of cause, body parts which not appling any repellent will infest with leeches and this is why Dr. Kirton recommended heavy or moderate spray on footwear, socks and trouser legs (tucked into socks to prevent the blood-sucking creature crawl up to other body parts from inner trouser legs).

I did a search in medical and science libraries about citronella oils and citriodiol oil, they are different types of essential oils. I have not tested ''Mosi-guard" in the field yet and no comments of it's efficacy.

Cheers!

Teo T P

[guldsmed]

Thx for this info - certainly useful!

[teotp]

Thx for this info - certainly useful!

You are welcome!

Teo T P

[Sunbeam]

I has been bitten by leech too. It bite through my thick hiking sock! It's hard to keep away from leech in the rainforest. The only way is don't stand still and let them have time to climb on your legs. Use urmbella to avoid leeches dropping from tree on you.

Never put away the leech by force, it will make your wound bleeding for a whole day. Just put some salt on the leech or let it fed up, then it will let you go without breeding a lot. I used to bring a small pack of salt (those available in McDonalds). Dr Lee tried to stop bleeding for our members using AA-glue. It works!

[Glorious Begum]

Interesting, I have not seen leech drops from the tree. Probably they are too tiny to be seen. I believe those from the top are Tiger leech. They used to stay at the tip of the leave. If you go too near then they will crawl up to you.

[teotp]

It is difficult to keep moving when you are doing your photography or looking for butterflies and other insects in the rainforest. Although leeches always on the ground but it will crawl up to small scrubs and waiting for the opportunities when animals like monkeys, lizards, deer... to pass by and stick on them. Once it bites, squeeze the Kaffir lime juice on it and it will immediately drop off (so keep two or three Kaffir limes in your pocket).

Teo T P

[MrGee]

We have a lot of leeches here and we always encourage our staff to use non-harmful methods of removal. This is relevant only to land leeches. Before they have bitten you, you can simply flick them off. Sometimes they can be a little stubborn so a good, strong flick is required. If they have already bitten or won't come off by flicking, put the back of your finger against your skin, with the tip pointing towards the leech. Then scrape your nail across your skin through the position of the leech. The leech will come off onto you finger tip, from where you can click it off.

[WillFolsom]

Guys: Don't have any problems with leeches here so I'm not familiar with what they do. Do they cause infection or are they just unsightly? In medieval times they used leeches for medicinal purposes. Here we have tiny ticks that drop down from above or crawl up your legs like leeches. Mostly unsightly, but deer ticks cause Lime Disease, a very debilitating disease that you must become familiar with if you visit the USA and go out into the field. William

[Painted Jezebel]

As some members here will know, I seem to have a curious affiliation with leeches, they just love me. I was lucky in Khao Sok, and only got bitten 3 times, a new record, usually, it is much more. (1Tiger and 2 normal black ones)

I simply find them annoying, they do no harm, but if you manage to flick them off, there will be an itch for a couple of days afterwards. If they have managed to bite you, put a small amount of tobacco on the bite, and the bleeding will stop in 5 - 10 minutes.

[Angiud]

From my body at Khao Sok ;-)

http://farm8.staticflickr.com/7276/7028299115_409dd2ca84.jpg (http://www.flickr.com/photos/angiud/7028299115/)
Leech (http://www.flickr.com/photos/angiud/7028299115/)

[Silverstreak]

We have a lot of leeches here and we always encourage our staff to use non-harmful methods of removal.

Leech sock is one way , but they are rather expensive on the net except those sold by Malaysia Nature society at KL , which cost around MR $25 if I remember it correctly.

If you do not go into leech infested forest often, here is another cheap way of preventing them attaching to you, Secret Anti-Leech "Weapon" (http://www.butterflycircle.com/forums/showthread.php?t=5723&highlight=leech) which cost less than SD $1 and can be used a couple of times.:) Knee length stocking is sufficient, wear it over your socks and the loose end of your trouser's legs.

Most of them stay in your shoes and try in vain to get through the stocking , but some adventurous ones will head up and go for your belly area. So tuck in your shirt , preferably T shirt as many a times they found the fold in button shirt and have a feast on you tummy area.

Do not leave your back pack on the ground on leech infested area , your sweat on the back pack is a magnet and they will head for it..........and you'll know what happen when you put your back pack on later.:whistle:

..... but Les has a problem as he is a leech magnet :bsmile: .... I remember he wore a full length panty hose and yet the leeches breached it at Selai , Endau Rompin, luckily missing his family jewels.:bsmile:



:cheers:

[Painted Jezebel]

..... but Les has a problem as he is a leech magnet :bsmile: .... I remember he wore a full length panty hose and yet the leeches breached it at Selai , Endau Rompin, luckily missing his family jewels.:bsmile:
:

So true, but it is not a problem! However, I do not seem to get bitten by Mosquitos. Which would I prefer? .... Let me get bitten by leeches every time. At least I known they are harmless!

[Psyche]

So true, but it is not a problem! However, I do not seem to get bitten by Mosquitos. Which would I prefer? .... Let me get bitten by leeches every time. At least I known they are harmless!

Lucky you. I have developed a hypersensitivity to leech bites. A bite will lead to angry red swelling, an oozy wound and a maddening itch. Even a light bite cause an itchy reaction.

More unnerving is the buffaloe leeches that live in water. These can stretch to 20cm. long.
You won't find me stepping into water at a river's edge if there are buffaloes around.
I once landed one in crystal-clear water next to a small waterfall, but I realised villagers have buffaloes further downstream & some may have wandered upstream. I don't think the leech made its way up against the current although it could do so close to the bank.

TL Seow:cheers:

[teotp]

Another concern about leech bite is other bacterial pathogens like Burkholderia pseudomallei and Leptospira interrogans may take this opportunity to enter our body and cause melioidosis or leptospirosis. This is why I used lime juice (acid to lower the pH may kill some microorganisms) and/or drinking water (reduce the microorganism numbers) to wash the bited wound and then stop the bleeding after that, although there is no report about Burkholderia pseudomallei infection or leptospirosis after leech bite but preventive mearsure is very important in the field.

Teo T P

[teotp]

The purpose of this write is to share with BC members the distribution, biology, behaviour and some preventive measures against leeches with special reference to the land leech, Haemadipsa zeylanica.

Blood sucking land leeches (Haemadipsidae) are distributed throughout much of the tropical Asia, Australasia and Oceania (Moore, 1938; Keegan et al, 1968). The best known species is Haemadipsa zeylanica which lives in mainland Asia from about 4,000 m in the Himalayas of India and Nepal to the Asian countries, southern China, as well as on offshore Asiatic Islands like Sri Lanka, Sundas, Taiwan, and Ryukyus to Japan where it confined to certain mountains (Sawyer, 1986).

The following blood sucking land leeches (Haemadipsidae) of South East Asia were documented by Professor Roy T. Sawyer:

Haemadipsa ornate (Moore, 1927): Known from the eastern Himalayas (Darjeeling, north-east Frontier, especially Assam; 500 - 1,000 m).

Haemadipsa picta (Moore, 1929): Known from the Malay Peninsula, (?) Celebes and Borneo, where it is characteristic between the range of 700 - 1,300 m.

Haemadipsa sylvestris sylvestris (Blanchard, 1894): Known from north-east India (especially abundant in Assam) throughout Myanmar to Thailand.

Haemadipsa sylvestris interrupta (Moore, 1935): Known fron Malay Peninsula, Thailand, and Indo-China and probably Java and Sumatra.

Haemadipsa cochiniana (Moore, 1927): Common in southern part of India, extending north on the western coast to Bombay from sea level to 1,100 m.

Haemadipsa montana (Moore, 1927): Known from Myanmar hills, southern India, Himalayas, usually 2,000 - 2,700 m.

Haemadipsa zeylanica subabilis (Moore, 1929): Known from Malay Peninsula and west Sarawak.

Haemadipsa zeylanica sumatrana (Horst, 1883): Known from Sumatra and Borneo, where it is the common ground leech in all parts of the island except west Sarawak.

Haemadipsa zeylanica zeylanica (Moquin-Tandou, 1826): Sri Lanka.

Haemadipsa zeylanica agilis (Moore, 1927): The common leech of western Himalayas, very abundant in region around Naini Tal, 1,700 - 2,000 m (1,000 - 3,700 m); also occurs in southern Indian hills (Palni Hill, Madras, Dhoai Forest, South Malabar); uncommon in Nepal.

Haemadipsa zeylanica montivindicis (Moore, 1927): Known from eastern Himalayas (common in Daarjeeling district, Sikkim and Assam, 1,500 - 2,200 m (600 0 3,800 m)) and Myanmar (Dawna Hills).

To determine the local and seasonal distribution of Haemadipsa zeylanica and other leeches is highly relied on the availability of moisture. In continually moist areas, such as the mountain areas of Malaysia and Borneo, land leeches are more or less active throughout the year. On the other hand in those parts of its range (e.g. northern India) subject to periodic dry and wet seasons, abundance of H. zeylanica is highly seasonal. Localities teeming with active leeches in the rainy season are virtually devoid of them in the dry season. During rainy period H. zeylanica migrate considerable distances (1 km or more) vertically up hills and horizontally into area normally too dry, such as unforested pastureland. As the rain cease the leeches retreat from drier, exposed locales and by the advent of the dry season, they by now of moderate to large size, are confined to damp areas such as near streambeds. Nevertheless they never voluntarily enter water. As the topsoil dries out the leech burrow into damp subsoil. On digging a foot or more, below the earth surface and on turning the underground buried stones, and pebbles in the vicinity of water channels, a large number of hibernating leeches were everytime found, attached to under surface of the stones. At this time the individuals are sluggish and unresponsive. With the advent of the rainy season the leeches quickly revive, couplate at the first opportunity and actively seek for a blood meal.

The normal host of H. zeylanica living deep in the undisturbed rainforest is unknown, but those living in distrubed areas feed voraciously on domestic animals, especially cattle, as well as humans. In laboratory, H. zeylanica reported to feed on frogs, snakes, mice, rabbits and even chickens. Occasionally land leeches have been found on wild birds, sometimes in their nasal passage. Undoubtedly birds represent one mechanism of dispersal which explain the widespread distribution of land leeches in Oceania (Sawyer, 1986)

Teo T P

(to be continued...)

[teotp]

Throughout the range of H. zeylanica (ground leech) lives exclusively on ground among fallen leaves on the damp forest floor, but its relatives, H. ornate and H. picta, both of which climb low-lying bushes. H. zeylanica is especially active in mornings and early evenings. It has a highly developed sensory system, including extraocular photoreceptors, and foraging individuals are very responsive to ground vibrations and overhead shadows. They are particularly sensitive to near by flow breath, of which carbon dioxide is reportedly the main detected component. Ground leeches are also attracted to warmth, at least upon physical contact with a warm object H. zeylanica moves rapidly and with great agility over leaves toward a host from a distance at least 1 or 2 metres. Once attached they probe the host skin with anterior tip of the oral sucker and select a suitable site for feeding (Keegan et al, 1968; Sawyer, 1986). Penetration of the skin is achieved in a further 80 - 90 seconds and blood sucking last for about an hour, during which an adult leech would ingest about 1 g. or more of blood. The bite of H. zeylanica is painless, unlike the "stinging leeches" H. ornate and H. picta. Various leech species solved the clotting of blood in different ways by using their salivary secretion to (1) anti-thrombin (hirudin), (2) fibrinogenolysin (hemetin), (3) plasminogen-activation and (4) inhibition of platelet aggregation. Following a meal the bite continues to bleed for about 30 minutes but coagulation time is delayed for only 10 minutes. The sated animal drops off and retreats to a protected location in the forest floor. After 4 to 7 days the leech will become progressively more active (Sawyer, 1986).

Land leeches including H. zeylanica appear to be capable of transmitting trypanosomes to their host. The best documented case of this is the transmission of Trypanosoma aunawa by Leiobdella jawarerensis to bat (Minopterus tristris) in New Guinea cave (Ewers, 1974). Similarly, active trypanosomes are known to live in the crops of Chtonobdella bilineata and H. zeylanica for at least 52 and 44 days after the last meal respectively. The latter species has been implicated as a possible vector for Trypanosoma evansi, causative agent for surra, an often fatal disease for domestic animals (Sawyer et al, 1982).

In addition, aquatic leeches like Hirudinaria manillensis is extremely voracious and aggressive animal. If one agitates the water, the leeches emerge from their resting positions in the mud and swin energetically toward the focus of water disturbance. These leeches may actually leave the water and attach to the animal or observer's foot. Upon making physical contact with the host the leech quickly attaches. A good example is a car stuck in mud and water, was spining its wheels in an attemp to become unstuck. After a few minutes of this the driver noticed a number of aquatic leeches firmly attached to the overheated tyre. Nasal leeches are encountered in the nasal passage or other external orifices of humans and animals. Juvenile nasal leeches are very small and live in water. When an unsuspecting person or animal drinks directly from infected water, a leech may quickly attach to the mouth or nares. It subsequently lodges itself deep in the nasal passage where it lives for many days or weeks. Initially in conspicuous it sucks blood periodically and grows rapidly by which time it causes considerable discomfort to its victim. A reported case is one removed from the nose of a woman from Kinarut, 24 km south of Kota Kinabalu (Hii et al, 1978). A leech species identified as Dinobdella ferox has been reported in the nasal passage of dogs at Kinabalu and also free living in mountain stream (Harrison, 1953; Walton, 1955) (Do not drink or wash your face with stream water in forest!).

Finally, I would like to mention a repellent (M-1960) used by the U. S. Army and British Colonial Office during the Second World War in Borneo. Field tests of army uniforms treated with "M-1960" by volunteers gave complete protection against land leeches H. zeylanica, H. picta and water leech Hirundinaria manillensis. A measurable and useful degree of protection remained after six cold washes (Audy & Harrison, 1954; Sharma & Fernando, 1961). The authors reported that clothing treated with "M-1960" has a distinct smell but does not seem to be offensive to majority of wearers. Land leech placed on a freshly treated sleeve showed distress, refuse to hold it with suckers, writhe and wriggle and throw out mucus. If it was not removed or did not escape as a result of its struggles and become limp, comatose after 5 to 10 minutes and would never recover. Repellent "M-1960" was developed for the U. S. Army by USDA as a general repellent against mites, fleas, ticks and mosquitoes. It consists of:

n-butylaoetanilide -----------------30%
2-butyl-2-ethyl-1.3 propanediol ----30%
benzyl benzoate -------------------30%
tween 80 (emulsifire) --------------10%

Hope the above information is useful to BC members and jungle trackers from overseas. Cheers!

Teo T P

References:

Audy, J. R. & J. L. Harrison (1954). Field tests of repellent M-1960 against leeches. Medical Journal of Malaya 8, no.3: 240-250.

Ewers, W. H. (1974). Trypanosoma aunawa sp. n. from an insectivorous bat Miniopterus tristris in New Guinea, which may be transmitted by a leech. Journal of Parasitology 60, no.1: 172-178.

Harrison, J. L. (1953). Leeches. Medical Journal of Malaya 8, no.2: 180-185.

Hii, J. L. K., S. K. P. Kan & K. S. A. Yong (1978). A record of Limnatis maculosa (Blanchard)(Hirudinea: Arhynchobdellida) taken from nasal cavity of man in Sabah, Malaysia. Medical Journal of Malaysia 32, no.3: 247-248.

Keegan, H. L., S. Toshioka & H. Suzuki (1968). Blood sucking Asian leeches of families Hirudidae and Haemadipsidae. 406th Special Report of U. S. Army Medical Command, Japan. 130pp.

Moore, J. P. (1938). Leeches (Hirudinea) principally from the Malay Peninsula with descriptions of new species. Bulletin of The Raffles Museum 14: 64-80.

Sawyer, R. T., A. Taylor & Mohd. Jaya bin Hj. Sahat (1982). The leeches of Brunei (Annelida: Hirudinea) with a checklist and key to the known and expected freshwater, terrestrial and marine leeches of Borneo. Brunei Museum Journal 5, no.2: 168-201.

Sawyer, R. T. (1986). Leech biology and behaviour volume 2: feeding biology, ecology and systematics. Clarendon Press, 374pp.

Sharma, R. E. & C. H. Fernando (1961). Leeches and their ways. Malayan Nature Journal 15: 152-159.

Walton, B. C. (1955). The 'nasal leech' Dinobdella ferox from Borneo and Malaya. Journal of Parasitology 41, no.6: 32.

[Silverstreak]

Wow!! *Salute*

Thank You Thiam Peng for taking the time to research and sharing this !!

:cheers:

[teotp]

Wow!! *Salute*

Thank You Thiam Peng for taking the time to research and sharing this !!

:cheers:

Thank you for your nice words, Sunny.

Teo T P

[Commander]

Quite a lot of useful information there, TP. :thumbsup: A good reminder not to underestimate these leeches, even though they may seem harmless when they bite us.

[Painted Jezebel]

Thanks very much for such detailed info, TP.

Much to think about when I leave my, fortunately, leech-free Island. I do usually carry limes and/or salt with me when on the mainland or abroad, but, I must admit, rarely use them.

[teotp]

Quite a lot of useful information there, TP. :thumbsup: A good reminder not to underestimate these leeches, even though they may seem harmless when they bite us.

Thank you for your kind comments, SK. I was surprised when I read the "nasal leech" article.

Teo T P

[teotp]

Thanks very much for such detailed info, TP.

Much to think about when I leave my, fortunately, leech-free Island. I do usually carry limes and/or salt with me when on the mainland or abroad, but, I must admit, rarely use them.

Not at all, Les. I just don't want to see any BC member get infestation or any disease from these creatures after they return from the field.

Teo T P

[Psyche]

What a detailed research, Teo.

I noticed the common land leech( H. zeylanica) goes as high as 4000m in some countries, as well as being found in Japan.

I am curious about the situation here in Sundaland. I recalled a botanist who wrote in his book about the relief from leeches after 3000 feet.
My own experience is that as you go past 2500 feet, where the air is distinctly cooler the leeches are rather rare.
For example, walking through the montane forest (above 3000ft.)of Gunong Ledang (Mount Ophir, at the border of Malacca & Johor, approx.4100ft.) where slipper orchids start to appear, I did not encounter any leech.
I also do not remember seeing leechs in Cameron Highlands(5000ft.).
Admittedly my experiences are rather limited.

BC members go regularly to Fraser's Hill and often are prone on the ground to get the best shots. This is at risk of inviting an ardent smoocher in the netherland.The town area is 1300m.(4000ft.), and the Jeriau Fall is 630m.(1900ft.)
Do any member noticed any difference in the number of these slimey vampires between the two spots?

The presence of leeches is of course dependent on the vertebrate hosts .
Forest trails with signs of wild pigs are likely to be swarmed with these crawlies.
Even in bright open areas, the banks of streams and canals in rural areas, where the ground is moist, are leech-infested because of cattles.
The steep trail up the side of waterfalls are leech-free (as far as I know)despite their foreboding looks.Since hardly any animal pass up the trail, any leech there could die of hunger.

TL Seow:cheers:

[Silverstreak]

BC members go regularly to Fraser's Hill and often are prone on the ground to get the best shots. This is at risk of inviting an ardent smoocher in the netherland.The town area is 1300m.(4000ft.), and the Jeriau Fall is 630m.(1900ft.)
Do any member noticed any difference in the number of these slimey vampires between the two spots?

One of the trail we dropped by last year within the town area was full of leeches. I had 5-6 of them on the boots within a few minutes of stoping by to shoot a skipper. Khew also experienced same in one of the jungle trails in the town area on one of his trip.

At Jerai waterfall , the puddling ground is too hot for leeches , but no idea about the forested area, I do not think any of us explore the trail in that area.

I think you are right on these suckers depend on the resident wild boars for their regular meals. wherever I see wild boar foot prints in an area they are always around.

During our Langkawi trip we stop near the top of Gunung Raya and I went just 30 meters into a trail, saw wild boar footprints, without stopping I turned back out and I had close to 10 on my shoes !

:cheers:

:cheers:

[teotp]

What a detailed research, Teo.

I noticed the common land leech( H. zeylanica) goes as high as 4000m in some countries, as well as being found in Japan.

I am curious about the situation here in Sundaland. I recalled a botanist who wrote in his book about the relief from leeches after 3000 feet.
My own experience is that as you go past 2500 feet, where the air is distinctly cooler the leeches are rather rare.
For example, walking through the montane forest (above 3000ft.)of Gunong Ledang (Mount Ophir, at the border of Malacca & Johor, approx.4100ft.) where slipper orchids start to appear, I did not encounter any leech.
I also do not remember seeing leechs in Cameron Highlands(5000ft.).
Admittedly my experiences are rather limited.

BC members go regularly to Fraser's Hill and often are prone on the ground to get the best shots. This is at risk of inviting an ardent smoocher in the netherland.The town area is 1300m.(4000ft.), and the Jeriau Fall is 630m.(1900ft.)
Do any member noticed any difference in the number of these slimey vampires between the two spots?

The presence of leeches is of course dependent on the vertebrate hosts .
Forest trails with signs of wild pigs are likely to be swarmed with these crawlies.
Even in bright open areas, the banks of streams and canals in rural areas, where the ground is moist, are leech-infested because of cattles.
The steep trail up the side of waterfalls are leech-free (as far as I know)despite their foreboding looks.Since hardly any animal pass up the trail, any leech there could die of hunger.

TL Seow:cheers:

Researchers like R. T. Sawyer, J. P. Moore and J. R. Harrison are specialists working only on leeches. They explored many countries looking for these blood sucking animals and also received specimens from museum workers (e.g. A. S. Pearse from Siam Museum, M. W. F. Tweedie and Prof. W.A. Young from Singapore, H. M. Pendlebury from Federated Malay States Museum, Dr. W. L. Schmitt from U. S. National Museum...etc) contributing samples to them for research purposes for many years. Numerous field trips, experiments and publications about leeches were carried out and also documented by them. My write-up is just a small abstract based from their comprehensive publications.

If leeches rely only on cattle and wild pigs to survive by now they became extinction and why they have so many species and "so" abundance at certain localities (of cause I do not know much about their ecology)? Beside the mentioned two hosts, many domestic and wild mammals, birds, reptiles, amphibians including fishes (marine and fresh water), turtles (fresh and sea water) are their hosts (some leeches also attach to fresh water crabs).

Just referred to a paper (title: Leeches from Borneo and the Malay Peninsula: Bulletin of Raffles Museum 10: 67-79, 1935) by J. P. Moore: He stated that H. picta, H. zeylanica sumatrana and H. zeylanica subagilis and two species of burrowing Erpobdellidae Gastrostomobdella monticola and Mimobdella buttikoferi were collected at elevations from 3,300 to 10,000 ft at Mount Kinabalu (if leeches like H. picta and H. zeylanica can survived as high as 10,000ft why can't they lives at 4,000 or 5,000ft). Another example: Mr. Tweedie found H. sylvestris interrupta and Gastrostomobdella vagabunde from hills of Perak.

We didn't searched (dig into the ground, overturn the soil and stones, tracking their hosts and collect samples...) for these creatures when we visited Cameron Highlands (I did not encountered leeches there too), Bukit Fraser (leeches encountered from few locations), Genting Highlands (No leeches too).. and other places like Kuala Kubu Bharu (none) and Langkawi (few locations). We are looking for butterflies and other insects up there. BC members went outing during sunny days (dry and hot) and these animals are retreated to their safe places, who went out to butterflying during rainy days? Leeches will have their favourite localities and time (at night?) and we may not there when they are active. Regarding how long leeches can survive after their last blood meal? I read somewhere in Sawyer's book, will find out when I visit the library again.

Teo T P

(Note: May I know which book written by the botanist about the relief of leeches after 3,000ft? If you can remember the title and author).

[Psyche]

Hi Teo,

I do not doubt the veracity of the papers you quote.
I was referring to the common land leech which I did not say feed only on cattles & wild pigs, but vertebrate hosts.
Neither did I say they are not found at high elevations, but that I have not seen them.
I have asked if the number seen at Fraser's Hill at 4000ft aree different than at lower down.
My intention is to see whether the cooler temperature have affected their number.

TL Seow:cheers:

[teotp]

Hi Teo,

I do not doubt the veracity of the papers you quote.
I was referring to the common land leech which I did not say feed only on cattles & wild pigs, but vertebrate hosts.
Neither did I say they are not found at high elevations, but that I have not seen them.
I have asked if the number seen at Fraser's Hill at 4000ft aree different than at lower down.
My intention is to see whether the cooler temperature have affected their number.

TL Seow:cheers:

Sorry, I misunderstand your intention, Seow.

I will find out whether any research papers discuss about the effect of temperatures on leech numbers at different altitudes, and also the survival time of leech under starvation. Cheers!

Teo T P

[teotp]

J. L. Harrison wrote in his paper (Leeches : Medical Journal of Malaya 8: no. 2, page164, Dec 1953) : "They can tolerate a considerable amount of drying, leeches which had become hard dry and motionless have been revived, but much needs to be done on this subject. Laboratory experiments suggested that they can tolerate up to about five months starvation."

Teo T P

More notes about food intake of leeches:

Generally, blood sucking leeches feed infrequently but take in large quantities of blood at one time. Hirudo species normally takes two to five times its own weight of blood and Haemadipsa species may take ten times its own weight. These large meals are digested slowly over a period of many months. Researcher carried out experiments and drew up detailed balance sheets for Hirudo species: A Hirudo leech of 128 mg took in 640 mg during one meal. The digestion of the meal took about 200 days and during that time there was a loss in weight by excretion of 524 mg. The balance of 116 mg had been incorporated into their tissues and as no further meal was taken the leech lived on its reserves for another 100 days. From this it is apparent that a leech will grow steadily if it obtains a meal every six months and it will not die of starvation (Reference: Leeches (Hirudinea) - their structure, physiology, ecology and embryology 1962, 201pp, edited by K. H. Mann; chapter 4 - nutrition: 36-43).

[teotp]

[QUOTE=teotp;112577] Land leeches including H. zeylanica appear to be capable of transmitting trypanosomes to their host. Similarly, active trypanosomes are known to live in the crops of Chtonobdella bilineata and H. zeylanica for at least 52 and 44 days after the last meal respectively. The latter species has been implicated as a possible vector for Trypanosoma evansi, causative agent for surra, an often fatal disease for domestic animals (Sawyer et al, 1982).

Trypanosoma evansi infections are quite common among horses, cattle and camels and normally does not infect humans. A case of T. evansi infection was reported by Joshi et al (2005) in a chronic patient in Maharastra state of India.

Reference:

Joshi, P.P., V.R. Shegokar, R.M. Power, S. Herder, R. Katti, H.R. Salkar, V.S. Dani, A. Bhargava, J. Jannin & P. True. (2005). Human trypanosomiasis caused by Trypanosoma evansi in India: The first case report. American Journal of Tropical Medicine & Hygiene 73: 491-495.

[teotp]

Hi Teo,
I have asked if the number seen at Fraser's Hill at 4000ft aree different than at lower down.
My intention is to see whether the cooler temperature have affected their number. TL Seow:cheers:

Population ecology of leeches is affected by factors of the environment, both living and non-living.

I. Inanimate environment:
Many factors under this category affect the distribution and abundant of leeches including H. zeylanica and H. picta. These factors include light, temperature, gravity and water.

Sunlight is a highly complex physical factor in the environment and also influences the temperature. On one hand it is harmful to leeches but on the other yields much information of condiserable usefulness to them. The useful aspects of environmental light are primarily those give information on the time of the year (photoperiodism: use as cues for leech reproductive maturation), time of day (diurnal rhythms: H. zeylanica is most active in the mornings and early evenings) and proximity of potential host (shadow reflex: see below). But light is not an essential factor for survival (this is demostrated in nature by species which lives in two sorts of continuously dark environments like caves (e.g. Dina absoloni) and ocean depths (e.g. Bathybdella sawyeri). Leeches are responsive to sudden decrease in light intensity (shadow reflex), especially in "hungry" individuals, the blood sucking H. zeylanica and H. picta both display these searching responses to an attraction toward a potential host (Sawyer, 1986a).

Many leeches spend all or part of their lives exposed to cold water. In most cases the rate of feeding decreases with water temperature, with some species more greatly affected than others. Some species are remarkablely active at low temperatures. The predaceous species Erpobdella octoculata stops feeding at very low temperature (1.5 degree C). In most cases rates of expression of elementary behaviours is directly dependent on ambient temperature. For example, the rate of inchworm crawling sequences of Hemiclepsis marginata correlates linearly with temperatures in the ecological meaningful range 5 - 25 degree C. At abnormally high temperatures there is a rapid decrease in the rate of crawling (34 - 37 degree C) leading to disorientation (37 - 41 degree C) and death (over 41 degree C). Thermoreception plays some role in host recognition in those groups with warm blood hosts (e.g. Hirodo medicinalis, H. zeylanica, Theromyzon tessulatum..). Unfed Hirudo medicinalis are strongly attracted to warm objects and display a behavioural preferrence to bite those warmed to 37 - 40 degree C objects. Specific thermoreceptors have not been identified but certain identified neurous reportedly have increases impulse frequencies when warm (35 - 45 degree C)(Mann, 1962; Sawyer, 1986a).

Some leeches give the appearance of responding to gravity. The most remarkable example of apparent negative geotaxis is that displayed by the land leech H. picta. This species has a behavioural proclivity for climbing low-lying bushes and if put into a jar they will repeatedly climb upward as the jar turned upside down. Gravity and geotaxis experiments carried out to test Hirudo medicinalis and Theromyzon tessulatum by placing them in tall glass cylinders (125 cm), both H. medicinalis (88%) and Theromyzon tessulatum (84%) showed repeatedly climb upward to the top of the cylinders. Haemadipsa zeylanica also has climbing habit, but up hills rather than bushes. Some species display positive geotaxis (e.g. Piscicola geometra and Hclobdella stagnalis). The precise cues involved on responding to gravity and geotaxis are uncertain, for some species probably oxygen plays a role on the behaviour (Mann, 1962; Bhatia & Bora, 1973; Sawyer, 1986a).

Water plays a very important role in determining the ecological distribution of leeches. In general leehces are most abundant in stagnant water and become less frequent as water current increases. Land leeches like H. zeylanica and H. picta need to keep thier entire animal moist, so their distal 17 pairs of nephridia are modified, the urinary bladder is relatively very large and opening of the terminal excretory duct (nephridiopore - instead of being in the typical ventral position) is lateral or actually dorsal to lateral margins. In addition, the last pairs of nephridia open onto a tri-lobed phlange-like structure called auricle. The middle lobe, which contains the nephridiopore, is triangular and the outer two have prolonged membranous margins which project caudally. These auricles act as damp brushes which distribute moisture over the surface and margins of sucker. This is to keep the sucker free of adhering debris on the surface. This is why land leeches are most active during or soon after rain when the substrate is moist. The differences between foraging in H. zeylanica and H. picta and their aquatic counterparts can be attributed to specialized adaptions to live on land. Both species display the behaviour of cleaning the oral and caudal suckers by rubbing the sucker against its own body or the substrate (auricles). Sucker cleaning is clearly a behavioural adaption to the sucker mode of locomotion (inchworm crawling and rarely vermiform crawling) on land and increases in frequency as the substrate become drier. Difficulty in manoeuvring on a dry substrate explains scarcity on land leeches after several days without rain, and also the distribution of these blood sucking animals on certain locations (Mann, 1962; Cameron, 1962; Sawyer, 1986a, 1986b & 1986c).

II. Animate environment:
It seems that only European leech species have been studied intensively so that conclusions can be reached about their habitat preferences. Information of land leeches is mainly confined to brief notes about their food organisms, but the following data may give some ideas about their food in relation to their distribution and abundance:

Hirudidae:
Hirudo spp (blood sucking on: Mammals, birds, reptiles, amphibians and bony fish).
Macrobdella spp (blood sucking on: Mammals, amphibians and bony fish).
Philobdella spp (blooding sucking on: Mammals).
Hirudinaria spp (blood sucking on: Mammals).
Haemopis spp (devouring: Molluscs, insects, crustaceans, worms and carrion).

Erpobdellidae:
Erpobdella spp (devouring: Molluscs, insects, crustaceans, worms and carrion).
Trocheta spp (devouring: Molluscs, insects crustaceans and worms).
Nephelopsis spp (devouring: Insects, crustaceans, worms and carrion).

Haemadipsidae:
Haemadipsa spp (blood sucking on: Mammals and amphibians).

Glossiphoniidae:
Batracobdella spp (blood sucking on: Amphibians and molluscs).
Hemiclepsis spp (blood sucking on: Amphibians and bony fish).
Theromyzon spp (blood sucking on: Birds).
Haementeria spp (blood sucking on: Mammals, birds, reptiles and amphibians).

Piscicolidae:
Piscicola spp (blood sucking on: Elasmobranchs).
Pontobdella spp (blood sucking on: Molluscs).
Branchellion spp (blood sucking on: Elasmobracchs and molluscs).
Abranchus spp (blood sucking on: Elasmobranchs).

Mann (1962) pointed out that only a few leeches are restricted to one kind of host (e.g. Hemibdella soleae to Solea spp; Callobdella lophii on angler fish). Majority of leeches while disposed to attack a particular kind of host will take meal where they can find one. For example, H. zeylanica attack mainly animals like mammals and amphibians (Mann, 1962) but they have been recorded on birds and reptiles (Sharma & Fernando, 1961). In comparison, the macrophagous forms take an even wider variety of food most of them will take any kind proteinaceous material that is offered including carrion or young of thier own species (Mann, 1962).

Undoubtedly, predators of leeches play a role on their distribution and population. The most important predators of leeches are fish, birds, aquatic insects, crayfish and other leeches (at least one leech species is a predator of other leeches). One third of the overall diets of the terrestrial garter snakes (Thamnophis elegans) are specialized predators on leeches (e.g. Haemopis spp) and earthworms (Sawyer, 1986a).

Looking over the very incomplete knowledge of the ecology of land leeches, it appears that factors influencing the distribution and abundances of these creatures are complex. Other factors like oxygen and calcium content of water, the rate of water movement and their competition with other organisms are not take into consideration.

The above abstract is dedicated to Seow. Again, my apology for the misunderstanding. Cheers!

Teo T P

Literature cited:

Bhatia, M.L. & S.S. Bora (1973). Bionomics and distribution of the land leeches of Kumaon Hill, U. P. Journal of Bombay Natural History 70, no.1: 36-56.

Cameron T.W.M. (1962). Parasites and parasitism. Methuen & Co. Ltd. London. 322pp.

Mann, K.H. (1962). Leeches (Hirudinea): their structure, physiology, ecology and embryology. Pergamon Press - London. 201pp.

Sawyer, R.T. (1986a). Leech biology and behaviour volume 1: anatomy, physiology and behaviour. Clarendon Press - Oxford. 418pp.

Sawyer, R.T. (1986b). Leech biology and behaviour volume 2: feeding biology, ecology and systematics. Clarendon Press - Oxford. 374pp.

Sawyer, R.T. (1986c). Leech biology and behaviour volume 3: Bibliography. Clarendon Press - Oxford. 226pp.

Sharma, R.E. & C.H. Fernando (1961). Leeches and their ways. Malayan Nature Journal 15: 152-159.

[Psyche]

Again an awesome amount of research in the subject matter, Teo.

Thanks for all the info.

TL Seow:cheers:

[Silverstreak]

Wow! I think we are the most well informed forum on leeches !!:)

Thank you Thiam Peng for doing all this research and sharing them with the forum!


Cheers!

[teotp]

Again an awesome amount of research in the subject matter, Teo.
Thanks for all the info.
TL Seow:cheers:

Thank you Seow for your kind comments and you are welcome.

Teo T P

[teotp]

Wow! I think we are the most well informed forum on leeches !!:)
Thank you Thiam Peng for doing all this research and sharing them with the forum! Cheers!

Thank you Sunny for your kind words.
I did suffered on many occasions bitten by the land leeches and knew the messiness have to clear up after bite. Any information that can help to prevent or against the bites from these blood suckers I will be glad to share with members. Sharing one more below:

A detailed study of the substances which evoke a reaction in leech species (Hirudo) was experimented by placing 5 leeches in 200ml of water in a dish and when they were at rest, test substances were added drop by drop. The results are shown below:

Substance (amount; 1 drop = 0.04ml): Reaction

Formic acid (1 drop): Quivering reaction, leave water.
Acetic acid (2 drops): Weaker reaction than above. After 5 mins anterior sucker out of water.
Proprionic acid (2 drops): As for acetic acid.
Iso-butyric acid (2 drops): As for acetic acid.
n-butyric acid (2 drops): Weaker reaction, leave water after 30 sec.
Oxalic acid (2 drops): Jerking and quivering, anterior sucker out of water.
Malonic acid (5-10 drops): As above.
Succinic acid (5-10 drops): As above.
Citric acid* (1 drop): As above.
Hydrochloric acid (1 drop): As above.
Phenol (1 drop): Shock reaction, leave the water.
Thymol (a crystal): No reaction.
Napthol (2 drops): Jerking and quivering, soon leave water.
Galactose; Glucose; Sucrose or Lactose (a crystal): No reaction.
Methanol; Buthanol or Glycerine (1 drop): No reaction.
Quinine; Caffeine; Atropine; Cocaine or Morphia (1 drop): Swim about restlessly then come to rest with anterior sucker out of water.
Ammonia (1 drop): Strong reaction,, leave water.
Urea (a crystal): Clear reaction.
Indol (2 drops): Leave water hastily.
Skatol (a crystal): Leave water hastily.
Champhor (1 drop): No reaction.

Leeches responded to acids with characteristic jerking and quivering movements, while various other substances evoked normal locomotory exploratory movements. Noxious substances caused the leeches to come to rest with their anterior sucker out of water but the rest of the body still immersed. This suggests that the chemoreceptors are confined to the head and the body in water and no longer aware of the noxious stimulus. Among the fatty acids the most marked effect was produced by formic acid. Sugars and alcohols produced no effect but alkaloids like quinine and caffeine gave rise to strong reactions. Substances such as ammonia and urea give rise to exploratory movements and substances which are distasteful to human, such as indol and skatol, evoked a strong reaction.

Teo T P

(Note: For sodium chloride, they reacted to a concentration of 7%).
* Agreeable with the use of lime juice to release the bite from land leeches.

(Reason of editing: Typing error and addition of "glucose".