International Vulture Awareness Day: Vultures in Singapore

(Photo by reurinkjan)

Today is International Vulture Awareness Day, and I thought it would be appropriate to write about records of vultures in Singapore.

But why do we need a day to celebrate vultures? As stated on the International Vulture Awareness Day website:

Vultures are an ecologically vital group of birds that face a range of threats in many areas that they occur. Populations of many species are under pressure and some species are facing extinction.

The International Vulture Awareness Day has grown from Vulture Awareness Days run by the Birds of Prey Programme in South Africa and the Hawk Conservancy Trust in England, who decided to work together and expand the initiative into an international event.

It is now recognised that a co-ordinated international day will publicise the conservation of vultures to a wider audience and highlight the important work being carried out by the world's vulture conservationists.

Yikes! Yishun home invaded by breeding wasps

Monkey problem getting worse: One even invades Khatib MRT Station

Weird spiky bug spotted near Yishun block gives passerby the creeps

Caught on camera: Rat scurries across supermarket's dairy section

STOMPer Sharon was surprised to see a rat scurrying across the supermarket's dairy section while she was shopping for ice-cream at Cold Storage in North Point yesterday.

When contacted, Sharon said:

"I saw a rat ran across the dairy section counters just as I was about to buy my ice-cream.

"This happened at about 4pm yesterday. There were a few Cold Storage staff looking into the rat problem but they did not stop us from taking any pictures.

"I always shop at Cold Storage for its fresh produce but now, I wonder how clean can this place be?"

Based on the apparently large size and heavy build of the rat in the photo, I would hazard a guess and say that it is a brown rat (Rattus norvegicus). This is the familiar urban rat seen in cities around the world, and goes by many other names; common rat, sewer rat, and Norwegian rat have all been used at one point or another to refer to this species.


(Photo by andrewsteeleuk)

Supposedly once native to the plains of China and Mongolia, this species has become extremely successful, colonising every continent except for Antarctica. Selective breeding of the brown rat has also given us the laboratory rats that are so vital in research, as well as the fancy rat varieties kept as pets.


Left: Laboratory rat;
(Photo by jepoirrier)
Right: Fancy rat;
(Photo by P a c i a)

Unlike many other rat species, the brown rat is a poor climber. It is an excellent swimmer, which has helped it to colonise many parts of the world, stowing away on ships and boats and disembarking or swimming for shore whenever an opportunity presented itself.


(Photo by natalija2006)


(Photo by Armando Caldas)

As can be expected, this species is very flexible and adaptable, and readily feeds on whatever food is available, whether it is trash, grain, birds' eggs (or even adult birds), or molluscs. This adaptability has inadvertently created ecological disasters for many species ill-prepared against such an adaptable and intelligent predator.

Predation, competition, and disease spread by the brown rat and other non-native commensal rodents has devastated the fauna and flora of many islands. In recent years, Campbell Island in New Zealand and Rat Island in Alaska have stood out as 2 examples of successful rat eradication efforts to restore threatened native wildlife, especially birds.


(Photo by Armando Caldas)

The story of Christmas Island is particular ironic, in that 2 species of native rat, Maclear's rat (Rattus macleari) and bulldog rat (Rattus nativitatis) became extinct at the turn of the 20th century, not long after the black rat (Rattus rattus) was introduced to the island. It is strongly suspected that the native rats were wiped out by disease spread by the foreign invader.

Apart from the brown rat, there are several other rat species that may be encountered in Singapore. I briefly discussed these species in this post from last year.

Among those other rat species which may be found in urban Singapore are the Asian house rat or Tanezumi rat (Rattus tanezumi) and Polynesian rat (Rattus exulans).

The Asian house rat was once confused with the black rat (Rattus rattus), which has been widely introduced around the world. The Asian house rat itself is possibly native to the Himalayan region, China, and Indochina, but has apparently been introduced to the Malay Peninsula, Indonesia, Philippines, and various island groups in the western Pacific.

Genetic research has indicated that many populations of black rat actually form a separate species, which has been split off and given the name of Asian house rat. Whether or not the black rat itself is found in Singapore remains to be seen, and requires further study; both species do not hybridise readily, even in places where both species are sympatric.

Like the brown rat, the black rat itself also goes by many names; some synonyms include house rat, roof rat, and ship rat. It is considered to be a poor swimmer, but a much better climber compared to the brown rat.


(Photo by Doug Greenberg)

Where both species meet, especially in temperate parts of the world, the larger brown rat is said to be more aggressive, displacing the black rat. Apparently, if both species are occupying the same building, an interesting partitioning of niches occur; the more terrestrial brown rat occupies the sewers and ground floors, while the more arboreal and agile black rat colonises the ceilings and upper floors. In the tropics, however, the black rat is generally more common and more widespread than the brown rat.


(Photo by Sexecutioner)

Formerly native to the Indian subcontinent, the black rat is also the rat species responsible for the spread of the Black Death across Eurasia during the Middle Ages. Fleas carrying the plague bacterium (Yersinia pestis) after biting infected rats transmitted the disease to humans, resulting in the death of millions of people. Even today, the threat of plague epidemic is still ever present, with the last major outbreak occurring in India in 1994.


(Photo by nrdsquash)

The Polynesian rat is probably native to mainland Southeast Asia, and has followed Polynesian settlers as they populated far-flung island chains; it is now found throughout the western Pacific, from the Philippines and New Guinea to New Zealand and even as far as Hawaii and Easter Island. Compared to the brown rat and black rat, it is much smaller in size.

There are numerous other commensal rat species found throughout Asia; these include the Indochinese forest rat (Rattus andamanensis), rice-field rat (Rattus argentiventer), lesser rice-field rat (Rattus losea), Himalayan field rat (Rattus nitidus), and Himalayan rat (Rattus pyctoris), not to mention several species of mice (Mus spp.) and the bandicoot rats (Bandicota spp.).

These commensal rodents can be serious pests in agricultural areas, and can pose a significant health risk. Here in urban Singapore, they fulfill a role as scavengers, feeding on our food waste, and in turn are prey for carnivores such as reptiles and birds of prey; research has shown that rats are the main prey of urban reticulated pythons (Broghammerus reticulatus). Like it or not, rodents are part and parcel of urban life, and controlling their numbers is often very much linked to how we manage and dispose of potential food sources.

Huge rats seen at Yishun Park

Something must be done to prevent a rat infestation, says STOMPer altonlsg, who was shocked to see huge rats and several burrows at Yishun Park.

This STOMPer says:

"These pictures was taken after a run on a bright morning, around the nearby Yishun Park when I was walking back home.

"I was looking at the scenery when I saw something odd.

"I saw a rat, not moving but still alive. Its size was quite big and from what I saw, it should be an adult one.

"This could be seen as trivial but I hope the relevant authorities can look into it as this area is a huge piece of land and easily neglected.

"I like the area as it provides a good running route but if I can see one rat there in the morning, I do not know what happens at night.

"Also, a few burrows were seen. Hope something can be done before they continue to breed."

Two trees in Yishun Park share one root

How did these two trees come to share a single root? That's what STOMPer Jerry wants to know after spotting the conjoined trees in Yishun Park.

He says in an e-mail dated February 20:

"Please see these pictures.

"I found these two trees in Yishun Park.

"It seems like both tall old trees have merged their roots. Or were they twins in the first place?

"How is the water distributed within the roots?

"Not sure how this could have happened."

Do you have any idea? Let us know.

The explanation is very simple: these trees are most likely part of a single organism.

Many plants have an extensive network of roots or underground stems that will send up new shoots at intervals. Thus what appears to be a grove of several trees may actually turn out to be a single "supertree", with the individual trees being clones of one another, having sprouted from the same root system. The quaking aspen (Populus tremuloides) is a North American tree well-known for this trait. Huge colonies may extend over several hectares, and collectively weight several tonnes. One such quaking aspen colony, nicknamed "Pando", which grows in the state of Utah in the United States of America, is estimated to encompass 43 hectares and weigh 6,000 tonnes, making it the heaviest known organism.


Quaking aspen grove in Utah. This grove is a part of "Pando"
(Photo taken from Wikipedia)

In Southeast Asia, the Nipah palm (Nypa fruticans) is similar in this regard; this palm appears to lack a trunk, but what's actually happening is that the trunk grows horizontally underground, with leaf fronds sprouting from it at intervals. Hence, dense stands of this palm growing in mangroves are often sprouting from a single trunk.