Happy Valentine's Day

Flower crabs (Portunus pelagicus)
Pulau Subar Darat (Little Sister Island), 31st August 2008

Don't these two crabs look as if they're doing the waltz?

And if all goes well, here's what happens next:


Hot crab-on-crab action!

Here's a few other photos I've taken of various critters literally doing it 'like they do on the Discovery Channel'.


Left:American bullfrogs (Lithobates catesbeianus)
Khai Seng Trading & Fish Farm, 20th December 2008;
Right:Common sea star (Archaster typicus)
Cyrene Reef, 9th May 2008;


Left:Coastal horseshoe crabs (Tachypleus gigas)
Tanjung Rimau, 6th June 2008;
Right:Lined nerite (Nerita articulata)
Changi, 18th October 2008;

Before I continue, I have to apologise for conflating romance with sex, but as you're probably aware, the rest of the animal kingdom does not really share our notions of love and romance. For a great number of species, the act of courtship culminates in what is best summarised as 'Wham, bam, thank you ma'am'.

Though us prudish humans might not openly talk about sex, it cannot be denied that sexual reproduction has had an invaluable part to play in the evolution of life on this planet. If you think about it, almost everything about life on Earth has to do with sex. The staggering variety of life, both past and present, has come about partly due to species evolving their own adaptations to survive and reproduce. Many physical features, from the peacock's dazzling train of feathers, to the antlers of a stag, exist only for a sole purpose: to attract mates. The struggle between predator and prey essentially boils down to who gets to live long enough to reproduce and ensure the survival of one's genes. If a species fails to reproduce quickly enough to replace the individuals that die, it eventually becomes extinct. A great variety of animal behaviour is motivated by sex. Hell, much of the course of human history has been all about people moving into new lands and having sex with the locals. In fact, the common thread that unites a great deal of lifeforms is that they are all seeking to improve their chances of successfully reproducing. Asexual or parthenogenetic organisms are unique and interesting to us, precisely because they don't have sex. Even plants do it, just that their form of reproduction tends to be more subtle and often requires the intervention of other species.


(Image from The Perry Bible Fellowship)


In 1999, the BBC produced a 6-episode documentary series and accompanying book focusing on sexual reproduction in animals, entitled Battle of the Sexes in the Animal World. Snippets from the series have been uploaded to YouTube. The original narration has been dubbed over in Russian, although I think much of the footage speaks for itself. Here's one clip that really brings the point across: a great deal of intra-specific fighting occurs because of male competition to gain access to females.




Another book that discusses reproduction in animals is the witty and humorous Dr. Tatiana's Sex Advice to All Creation: The Definitive Guide to the Evolutionary Biology of Sex by Olivia Judson.


Gideon Defoe's How Animals Have Sex: A Guide to the Reproductive Habits of Creatures Great and Small is a decidedly tongue-in-cheek look from the perspective of a layman at some of the strange and often downright bizarre reproductive habits of other species.


Here's a few other books about animal reproduction which I haven't managed to get my hands on yet. These are A Natural History of Sex: The Ecology and Evolution of Mating Behavior by Adrian Forsyth, Promiscuity: An Evolutionary History of Sperm Competition by Tim Birkhead, and Sexual Selections: What We Can and Can't Learn About Sex from Animals by Marlene Zuk.


A very interesting book that deals with sexual behaviour of a rather different sort is Biological Exuberance: Animal Homosexuality and Natural Diversity by Bruce Bagemihl, which extensively discusses the prevalence of homosexual behaviour in a wide variety of animals.



Four books that explore reproduction from a more human perspective are Why Is Sex Fun?: The Evolution Of Human Sexuality by Jared Diamond, The Red Queen: Sex and the Evolution of Human Nature by Matt Ridley, Sperm Wars: Infidelity, Sexual Conflict, and Other Bedroom Battles by Robin Baker, and Bonk: The Curious Coupling of Science and Sex by Mary Roach.

I thought it would be appropriate to show the reproductive behaviour of some reptile species that can be found in Singapore. Many people are familiar with the mating displays of mammals and birds, but not many are aware of the fascinating displays of many reptiles.


Malayan water monitor (Varanus salvator)


Estuarine crocodile (Crocodylus porosus)


King cobra (Ophiophagus hannah)

I couldn't find any clips of reproductive behaviour in Singapore's native species of turtle, but to make up for it, here's a clip of tortoises mating:


Aldabra giant tortoise (Dipsochelys dussumieri) in Singapore Zoo

Tetrapod Zoology: Terrifying sex organs of male turtles

To conclude, it does get quite hilarious when animals get it wrong.


A male Asian toad (Duttaphrynus melanostictus) tries to get it on with a male American bullfrog (Lithobates catesbeianus).
(Original image from Wildlife Singapore)


Cane toad (Rhinella marinus) and... beer can?
(Original image from Terrapin Procrastination)

Tetrapod Zoology: Shocking inter-racial sex scenes

Now if you'll excuse me, I need to go read up more about the birds and the bees...

Fighting fish sleep above water

Look at the damage wreaked by S'pore's own bush-fire in Sengkang

YW was cycling along Upper Serangoon Road when he noticed a huge section of bushes burnt to the ground, leaving only ashes. This brings to mind the raging bushfire in Australia, which has claimed the lives at least 180 people at last count. He says:

"I was just cycling through the area, and for a moment I thought, 'Wow, the bushes all cleared, very nice. It's kind of like autumn.'

"Then I realised something, 'Oh my god it's a bushfire aftermath!'

"You can see how clear the path was after the bushfire.

"Made it kind of scary to cycle through that whole area you know?

"Oh, I pin-pointed that place, it seems like Google updated the map as well.

"By the way, the place that got devoured by flames was huge!

"Now you can even see into the cycling path from the road!

"I am not sure when it happened, I cycle through here often to my friend's place, so I would say it definitely happened two or three days ago.

"oh yeah, the smell was 'horigible', that's like terrible and horrible coming together. It was worse than charcoal!"

Go here for relevant news articles and related Seen on STOMP posts on bushfires in Singapore

I'm trying my best to ignore the cringe-worthy text. (Seriously, 'horigible'?)

Coincidentally, earlier this morning, I was discussing with one of my classes how a lack of rain can lead to bushfire. A few of my students mentioned that they had witnessed the effects of these fires, either by seeing the smoke from their homes, or travelling past the burned sites.

Although some of the wildlife living in these patches of scrub and belukar would be adversely affected by the fire, it is likely that the area will soon be quickly repopulated. In any case, the devastation and impact of these localised wildfires is nothing compared to the tragedy that has struck parts of Australia. I certainly hope that this atypical spate of hot and dry weather is not a sign of a long-term shift in our weather patterns. Unlike savanna and sclerophyll communities, I don't think our local vegetation is adapted to survive regular cycles of burning and regrowth.

By the way, I'm doubtful that Google has actually updated its satellite images

Why so many dead fish in Rochor River?

STOMPer Chan wonders why there were so many dead fish in Rochor River when he went there yesterday (Feb 10).

He said:

"Yesterday (Feb 8), I passed by the Rochor River and found many dead fish floating along the river.

"On weekends, many people go fishing there.

"Can the fish caught be eaten?"

Related Post: Dead fish clog this waterway near Toa Payoh flyover (29th January 2009)

I'm sure there is nothing that can stop people from consuming fish caught from Rochor River. It's more about whether the fish should be eaten in the first place; who knows what pollutants might have accumulated in the bodies of these fish.

Besides, I think the cleanliness of the water is a far greater concern. After all, the Rochor River drains into the Kallang Basin, which forms part of the Marina Reservoir.

My guess is that this mass death is a result of the hot and dry weather we've been experiencing lately, which would have led to a drop in the level of dissolved oxygen. In our concretised canals and rivers, the high temperatures and lack of oxygen would prove to be a lethal combination even for the hardy fish species commonly found in our urban waterways.

Monday Morgue: 9th February 2009

Spotted moon crab (Ashtoret lunaris)
Pulau Ubin, 18th October 2008


Wild Fact Sheets
Online Guide to Chek Jawa
A Guide to Seashore Life in Singapore
SeaLifeBase

Ticked off

I try my best to be a responsible dog owner, and that includes ensuring that my dog gets plenty of exercise. She is quite an active dog, and spends quite a lot of time running around the house, chasing her favourite toys and just being her usual inquisitive and curious self.

I have always had this strong desire to bring her downstairs for daily walks, so that she won't be cooped up at home all the time. There is a little park close to my block, and I did have a habit of taking her for a walk through the park for between 15 minutes to half an hour every night. She gets some exercise, and a chance to socialise with other dogs. It's always great to see how happy and excited she is when she's out on these walks.

Unfortunately, I've had to stop bringing her downstairs, because of the fact that my neighbourhood is apparently infested with ticks.

It's been a problem that we've been encountering ever since she joined our family 7 years ago. There have been times when we try to walk her daily, only to stop doing so a few weeks later after we discover all the ticks hiding in her fur. Keeping her away from grassy areas doesn't seem to help; it's as if these tiny bloodsuckers home in on her the moment she sets foot on the pavement. Whenever this happens, we end up spending a great deal of time on medication and grooming, to make sure that we remove all the ticks. And of course, it means that we stop bringing my dog downstairs, so she has to make do with running around the house, and occasional trips down the corridor to meet the yappy little pomeranian two houses away.

However, this most recent episode has proven to be especially distressing, because it now seems that the ticks are breeding in my house.



It's already been more than 2 months since the first few ticks were discovered, and since then, my dog has not gone downstairs. Yet we're still finding ticks hidden in her fur on a daily basis, so it's quite clear that the ticks have been able to lay their eggs in all the little nooks and crannies of the house.

Ticks gross me out. There's something very disturbing about the way they swell up like little blood-filled balloons after they've had a good meal. Not to mention the fact that they are important vectors for a wide variety of diseases that affect humans and domestic animals. Thank goodness Singapore is free from Lyme Disease and Rocky Mountain Spotted Fever. As if that was not bad enough, the saliva of several tick species even contains neurotoxins that can lead to Tick paralysis.

Unlike other parasites commonly found on house pets, such as fleas and mites, most tick species are unable to complete their life cycle indoors. Unfortunately, one species is capable of doing just that, the brown dog tick (Rhipicephalus sanguineus). This species is cosmopolitan, and is known to occur in Singapore. Based on the images I've been finding on the Internet, and the fact that they're breeding in my home, it's very likely that the ticks I've been finding do indeed belong to this species.

Here's some links about this species:

• Featured Creatures


• Pestproducts.com


• Urban Knowledge Master


• Tick Alert


• Green Valley Pest Control


• Illinois Department of Public Health

As its name indicates, it feeds largely on dogs (Canis lupus familiaris), although it will feed on other mammals. Humans seem to be very uncommon hosts, and considering that we haven't been finding ticks on our own bodies, I guess we're safe for now.

Although ticks cannot fly like mosquitoes, nor can they jump like fleas, they are nonetheless very good at seeking out hosts. Body heat and carbon dioxide are among the cues that ticks will use to detect prey. Hungry ticks will climb up bushes and blades of grass, and wait with their legs outstretched. If a suitable host brushes past, the tick will quickly grab on, and then crawl to a suitable spot where it can begin feeding. They can survive for extremely long periods without feeding, even up to a year, so great persistence is necessary if one is to eradicate them from the home or garden.


Deer tick (Ixodes scapularis)
(Photo by johnhallmen)

The brown dog tick requires 3 meals to complete its life cycle. In households that have only one dog (like mine), the same poor dog sustains every stage in the life cycle, from larvae to nymphs to adults.

After a tick has had its fill of blood, which can take a week, it will drop off and crawl away. In the case of an adult female, she will lay up to several thousand eggs, and then die shortly after. The larvae (also known as seed ticks) that hatch are tiny, and have only 6 legs. After their first meal, they drop off and then moult into 8-legged nymphs. These nymphs will then look for another meal, drop off, and finally turn into adults.


(Photo by loxosceles)

I love reading about parasites and their amazing adaptations, but it's not so pleasant when I have to deal with them on a personal basis.

I wonder if there's something about my dog that makes her especially attractive to ticks, or whether all the dogs living in my neighbourhood are also suffering from tick infestations.

Every day, we meticulously inspect my dog for ticks. It's quite easy to spot the fat grey bodies of the grossly bloated females. However, they have this annoying tendency to attach themselves to the skin between my dog's toes, and at the base of her nails. The smaller males and nymphs are much harder to find, and they crawl very quickly. It's not a good sign when we routinely manage to find ticks hiding in her fur every day, and have even spotted ticks crawling up our walls and cupboard doors. On an amusing note, my sister's teddy bear was also found to be infested with ticks, though I'm sure the ticks must have been frustrated at their inability to extract any blood.



Most of the ticks we find are gently removed, then immediately squeezed until they burst, leaving a splatter of blood and smashed tick bits on the tissue paper. It's disturbingly satisfying, especially with the engorged females; it's a lot like popping a huge pimple. I decided to keep a few alive in a small bottle out of curiosity.



It's amazing to see how long these ticks have managed to survive without food; most of these ticks have not fed for at least a month. They seem to go into a state of dormancy while waiting for their next meal. On more than one occasion, I've opened the bottle, breathed lightly on them, and watched as their seemingly lifeless bodies sprang into action and they raced for the rim of the bottle. So far, I've been quick enough to prevent any of them from escaping.

As if a bottle of ticks isn't bad enough, last week, the females started laying eggs.



I didn't take any more recent photos, but right now, there are even more eggs than what is shown in these photos.

I'm not sure if the females have finished laying, but they have been losing condition; first they started deflating, then their glossy grey bodies started developing yellowish patches. I guess they're going to die soon, once they're done laying all their eggs. I'm not so sure about the others though. I don't know if they're adult males or nymphs, but these smaller ones are definitely very feisty. In fact, they seem even more active lately; I think the hunger has gotten to them.



Needless to say, I am not a fan of the superhero known as The Tick.



Marcus has been bugging me to show them to him, so yesterday, during our TeamSeagrass monitoring session at Pulau Semakau, I passed him my bottle. To say that everyone else was extremely disgusted is an understatement. I hope he has fun trying to photograph them.

For now, the tick infestation seems to be dwindling, but we cannot afford to let our guard down. Regular baths, daily inspections, and frequent applications of Hartz® ADVANCED CARE™ 2 in 1® Flea & Tick Killer are the 3 main strategies we've adopted, and my poor dog is taking all this in her stride. I'm wondering if we need to get something more potent; Hartz® does have other anti-parasite products, I've read favourable reviews for Frontline®, and a friend just recommended Revolution®. I am a little apprehensive about the toxicity of these treatments, but at the same time, I want to get rid of these annoying little arachnids once and for all.

If you're brave enough, there's quite a lot of photos of ticks over on Flickr; there's even a group dedicated to sharing photographs of ticks.

But this has got to be one of my favourite photographs of a tick. It's disgusting, but you have to admit that it's an awesome shot, considering the size of the subject matter.


Rocky Mountain wood tick (Dermacentor andersoni)
(Photo by mplonsky)

I try my best to convince other people that every species on Earth has a vital role to play in the ecosystem, even those species that we consider pests, or those which spread life-threatening diseases. But even I have to admit that right now, I am not really a fan of ticks.

Snake found in Yuan Ching Sec

This slithery find was made on a drain slab in the school, and the STOMPer who spotted it alerted the security guard, before going off to work.

The STOMPer MMSed us on Feb 7, and said:

"Snake scene at Yuan Ching Sec Sch."

She added that when she chanced upon it, it was coiled up, and is hence unable to give an estimate of its size.

Nonetheless, she alerted the school's security guard, but because she had to go off, she was unable to find out what happened subsequently.

Related post: 10 ft python found at Pasir Ris HDB void deck (15th January 2009)
Beware! Snake skin spotted in Ang Mo Kio (20th January 2009)

The snake in question appears to be a young reticulated python (Broghammerus reticulatus). This is one of our most common urban snakes, and they are known to flourish in our midst, hunting rats in our drains and sewers.

The threat to human lives posed by these snakes has been grossly exaggerated. While pet cats and dogs might be at risk, pythons of this size are quite harmless to people unless cornered. I hope the python was left alone to mind its own business.

Of course, there have been more than a few cases where pythons in our sewers have crawled up and emerged from toilet bowls, which must be quite a harrowing experience for anyone using the toilet at that time.

Pythons don't have specialised fangs like cobras and vipers, but they do have rows of sharp teeth that help them get a firm grip on prey.


Reticulated python skull
(Photo by boneman_81)

I shudder to think of the damage should the python strike out at certain sensitive areas of the human anatomy...

Water in Clementi canal turns bright blue

STOMPer Lily was shocked to discover that the water in a canal at Clementi West had turned bright blue in colour. The STOMPer was puzzled by this strange phenomenon which lasted for a couple of hours.

Lily says:

"I saw this in the afternoon today(7 Feb) at around 4pm.

"I don’t know why the water turned bright blue in colour. It lasted for a couple of hours and now it is less noticeable.

"I just hope that it is not some kind of pollution as there are a lot of wildlife in this area, such as kingfishers and cranes, which drink and feed from the canal."

The canals in the Clementi area probably drain into Sungei Ulu Pandan. Further downstream, one can find one of Singapore's last few remaining patches of mangrove forest. It's always a little worrying to hear about such cases of pollution occurring in our urban waterways, since it does affect the health of the aquatic ecosystems downstream, and possibly even the marine habitats found around the river mouth.

It does make me wonder if the cleanliness of the water in the Marina Reservoir is at risk of being compromised, since the Kallang and Singapore Rivers drain quite a large area of urban and suburban Singapore, and all it takes is one irresponsible company or even a single individual to render the entire reservoir unusable.

By the way, the 'cranes' mentioned by the person who submitted the post are most probably egrets or herons (F. Ardeidae), since no species of crane is native to Singapore.

The beauty and ugliness of Little Guilin

A STOMPer shares his fondness for Little Guilin, with all of its myriad sights and sounds. Like all public places in this urban jungle, the park can be at once both beautiful and ugly.

In an email yesterday (Feb 3), the STOMPer wrote:

"Little Guilin is the only 'green lung' for the residents of the HDB flats and private condos at Bukit Batok East Avenue 5.

"The beauty of Little Guilin is reminiscent of that of its namesake in China.

"Some came to exercise their body, some came to fish and some came to create a mess for the cleaners employed by NParks.

"For those who love nature, Little Guilin has both wind and water and that is why the 'feng shui' here is superior to that of other parks.

"On weekends there are hordes of brides, bridegrooms and photographers who make a beeline for this lovely park. No wonder they say that marriages are made in Little Guilin and not in heaven.

"Photo 1: A spotted dove (Streptopelia chinensis) searching for food early in the morning.

"Photo 2: The rocks and trees of Little Guilin. Private condos can be seen in the background.

"Photo 3: Two old men sleeping in the park. One was using his boots as pillows.

"Photo 4: A man sitting on a rock. He was watching the anglers who came here to fish.

"Photo 5: A broken bottle left behind by some foreign workers."

Not much to say about this post, since I am very busy today, but it does go to show how the thoughtless actions of some park visitors can thoroughly spoil the beautiful surroundings.

The nearby Bukit Batok Nature Park is home to some Malayan colugo (Galeopterus variegatus), as shown in this older post in STOMP, and is also one of the remaining strongholds of the straw-headed bulbul (Pycnonotus zeylanicus) in mainland Singapore. A small population of the endemic Singapore freshwater crab (Johora singaporensis) has also been recorded to live in the park, although it is likely that this critically endangered species has vanished from this site.

Tree growing on old shophouse may cause pillars to give way

A STOMPer is worried about the damage caused by a sapling that is growing on the wall of a shophouse in Middle Road.

He says:

"These pictures were taken at an old shophouse in Middle Road near a Hainanese chicken rice shop.

"The sapling of a fast growing tree is growing beside a gutter of an old shophouse.

"One day when the tree is fully grown the wall of the shop may collapse and the pillars will also give way.

"It is clear nature is stronger than man-made concrete because time is not on our side."

Related post: This tree has claimed a bridge of its own (30th January 2009)

Such scenes are a reminder that if the human species should disappear one day, our cities will not remain standing for very long. Sooner or later, plants will take root in the cracks and crevices, and just as how they've been turning rocks into soil for millennia, will do the same to concrete.

I'm reminded of this short animated film, showing the vast expanse of geological time, and how the last few thousand years of human civilisation are just a blink of an eye in the Earth's history.

Ficus fruits grow on raintrees?

Monday Morgue: 2nd February 2009

Arabian cowrie (Mauritia arabica)
East Coast Park, 22nd May 2008

Wild fact Sheets
Hardy's Internet Guide to Marine Gastropods
SeaLifeBase