Nature Notes

We had to fell a 23-year old Hopea odorata in July as it was threatening to fall on either Kak Putih’s house or the spare staff cottage: the main trunk had split into two leaders, neither strong enough to carry the weight of branches and wind. Soon after palnting these we realised that rainforest trees must be planted well away from buildings. Girth was 2 meters, and we are keeping the trunk to mill into timber. If anyone knows of a portable mill that could come and do the necessary, do let us know!

Another smaller tree had to be felled to enable the hired cherry picker to access the Hopea odorata, manoeuvring into position in the tight space between the buildings. After Raya we will hire the cherry picker again to remove all split trunks along the driveway, retaining just the strongest.

In other news, a juvenile Asian palm civet fell into the middle well of the underground gallery at Rimbun Dahan and had to be rescued. The glass doors of the well were opened, and it escaped into the gallery, where it quickly found a nice dark space in the storage area, and was difficult to persuade to leave. Angela has given instructions that if it happens again, a ladder is to be put down into the air well. It works for snakes, so it should work for musang too!

This morning we had a snake alert: python in the hen house, again! This time three dead birds, one already consumed, two lined up ready to be eaten. When the snake was bagged, Lubis estimated its weight at 6 kilograms, including the eaten chook, as it didn’t have the amazing foresight of our last python who realized if you chuck it up, you might escape. This one was captured and released near a local stream with dinner to digest.

The otters are back, and they are bristling! Having been our occasional visitors for a few months, we are no longer surprised by the odd spraint by the side of the swimming pool, but so far direct contact between humans and otters at Rimbun Dahan has been rare. This morning Angela Hijjas had a thrilling encounter with our fish-eating friends:

“I woke with the azan this morning to hear desultory barking by Samson and Santan… I went out because it sounded a bit odd, and when I turned on the loggia light a big splash near the blue pots indicated something large in the water. It had to be an otter. I turned off the light and retreated with dogs in the house.

“I watched for the next 45 minutes and then gave up, but it was starting to get light and from upstairs I could see waves in the lower pond, so I got my camera and went down even though it was still dark. The dogs didn’t see me as I was behind the hedge, and I could see there were about 6 of the otters cruising around in formation. I think they hunt together by herding the fish into a corner and then attacking. They were catching fish but I didn’t see any eating.

“It quietened down, and I realised they were in the upper pond so I followed via the edging of the reflective pond and of course Santan and Samson saw me and followed. I thought the game would be up if the dogs got wind of the otters, but no indeed!

“The dogs went down to the divide between the ponds and the otters attacked! Four of them, heads rearing out of the water simultaneously towards the dogs, and then advancing out of the pond and onto the grass! Of course my faithful dogs retreated and were going to go home, but it would have been a huge loss of face with me there to protect. I had my SLR camera, and was clicking continuously although not with the camera to my eye, so most of the shots were out of focus but I was so close I had to get something, and I felt that if the noise of the camera continued they wouldn’t bother with me, but eventually when I was thinking I should retreat they realised I was there and disappeared.

“What an exciting morning!”

A group of otters is variously called a family, a bevy, a lodge or a romp, or, when in the water, a raft. At Rimbun Dahan, we might call ours an attack.

Over the new year, we restocked the reflective pool between the main house and the guest house with baby koi. At the time, the reflective pool was home to a vast hoard of black tilapia, as well as five or six mature koi over a foot long.

Shortly after the introduction of the baby koi, all the mature koi and a number of the baby koi disappeared. At first we suspected infection. Ragged remains of koi were found near the swimming pool, suggesting that monitor lizards — of which we have many, and some very large — had been making free with the fishy remains. However, members of the staff at Rimbun Dahan said it was the work of musang (civet cats, or mongoose). Musang? we queried, but musang don’t swim! Oh yes, replied the staff knowingly, musang swim very well, and when there is food for them they call all their friends!

Mystified and doubtful, we held onto our first infection theory. A few days later, the staff clarified: No, we didn’t mean musang, we meant memerang. Otters? Even less likely.

Then early one morning Angela caught a glimpse of massive disturbance in the swimming pool, and then spotted two very large otters, one of them devouring the last of the koi. Characteristic spraints (otter droppings) have also been discovered on the swimming pool edge. The animals are so large that the Rimbun Dahan dogs have so far left them prudently alone.

From our brief sighting, it is impossible to accurately define what species of otter these are. There are several species native to Peninsula Malaya, including the Eurasian otter (Lutra lutra), the endangered hairy-nosed otter (Lutra sumatrana), the smooth-coated otter (Lutrogale perspicillata) and the Oriental small-clawed otter (Aonyx cinerea). All are very similar, and some can only be distinguished by careful analysis of nose hairs and skull specimens.

No matter their species, the voracious animals have effectively cleaned out the fish population of the reflective pool. All the koi are now gone, and the tilapia population more than decimated. In order to cater to their enormous appetites, otters are required to have a huge territory, so it may be likely that our furry swimming visitors have come and gone… until we restock the pond for their dining pleasure.

With the La Ninya weather this year, we have had constant rain and virtually no rainy season, but a few things in the garden are flowering at the moment.

Alstonia angustiloba, the common pulai tree (left), initiated this feature on current flowering as one of our trees was laden and the fragrance permeated the plaza, but like so many tropical plants the flowers are small, short lived and either white or green. The unusual fragrance lacks the sweetness of more temperate flowers but it punctuates the experience of walking in our tropical garden.

The louvred sculpture by Darwin artist Brian Ash was destroyed in early February by strong winds that broke a branch from one of the Shorea materialis trees near the front fence. Asialink resident artist Brian Ash created this untitled work in 1999 from aluminium and mirror louvres to reflect the vertical nature of the young dipterocarp grove in the southwest corner of the garden. The long tailed macaques had repeatedly damaged the sculpture in the past, presumably because of the mirrors, or perhaps they just thought it a different kind of climbing frame.

S. materialis is an extremely heavy balau timber that used to be fairly common on the east coast of the peninsula from Terengganu to Endau, on low-lying usually sandy soil near the coast or on tidal reaches of rivers. Ten were planted at Rimbun Dahan where the soil is sandy and most have thrived. The tree which is the culprit of this artistic attack will be pruned further to reduce the canopy load, and a creeper will be planted at the foot to reinforce it and counter lightening strike.

For more information about the Shorea at Rimbun Dahan, see the plant list of Dipterocarps. For other outdoor sculptures, see selections from the permanent collection.

Breeding season is coming, and good nesting property is in short supply.

Our sole gold-whiskered barbet (Megalaima chrysopogon) industriously excavated a hole in the dead tree trunk near the main house, which is a favoured perch of all species of birds.

The family of black-thighed falconets (Microhierax fringillarius) then decided to move in, but were chased off by a pair of dollar birds (Eurystomus orientalis). However, the dollar birds found the hole too small for them and they in turn were forced off by the tenacious falconets. What is possibly the male falconet sits at the top of the tree on the lookout, with the female going in and out of the hole, resting in an adjacent tree before entering hole to make sure no one is watching.

The 16th of December was a red-letter day for birdwatching at Rimbun Dahan — we got our first good photographs of a barred eagle-owl. Our first sighting of this impressive predator had occurred at dusk several days before, when the alarm screeches of drongos alerted us to its presence in a tree in the Taman Sari. The three drongos were swooping and calling around the owl, but none dared to get very close.

The owl was very tolerant of our staring, and even more so when we finally caught it on camera a few days later while disturbing its daytime nap. We were lucky enough to have our friends Akshay Sateesh and Brooke Resh visiting with their digital SLR to take some good shots.

The eagle-owl has been seen several times resting in the same ipoh tree, Antiaris toxicaria, beside the steps of the dance studio, gripping the branches with its enormous yellow feet. Once two individuals were observed sharing the same tree, enjoying a communal snooze.

The barred eagle-owl (Bubo sumatranus) is found in Myanmar, Thailand, Malaysia, Indonesia and Brunei, and is now thought to be extinct in Singapore. It is a resident from low elevations up to 600m, and frequents forests, the forest edge, overgrown plantations and heavily wooded suburbs of towns and cities. Like other typical owls it is nocturnal, hunting from perches and flying low to locate prey after dusk. (Jeyarajasingam & Pearson, 1999)

The barred eagle-owl is the largest of several species of owl occasionally encountered at Rimbun Dahan. Other owls that have been seen include the barn owl (Tyto alba) and a smaller scops-owl.

On the same day as the owl sighting, a drongo cuckoo flew into the main house at Rimbun Dahan and became disoriented and trapped in the television room. After barging about and crashing into the walls and ceiling, it finally managed to find its way out through an open window, and flew off apparently none the worse for wear.

The drongo cuckoo (Surniculus lugubris) is a glossy black bird with a down-curved bill and a forked tail. It is a resident, passage migrant and winter visitor to Malaysia, inhabiting the forest and the forest edge. Usually keeping to the canopy and the crowns of tall trees, it does not chase insects from an open perch in the manner of real drongos. A parasitic cuckoo, it has been known to lay its eggs in the nests of the Striped Tit-Babbler, leaving the foster parents to incubate the eggs and raise the young. (Jeyarajasingam & Pearson, 1999)

The stormy season is in full sway in mid November with rain every day; often it’s dark by 5 as the clouds close in and the dogs all go to ground. It’s a wonderful time for the garden, although it has its dramatic moments.

Lightening strike is something I have long been aware of, as our trees are now the highest things around, but we are making progress there. My theory is that with creepers, big or small, going up and through the trees, any tall tree is effectively earthed. The only problem is getting them established without engulfing the tree with exuberant growth. On last week’s walk in Rimba Ilmu, we noted a terap tree that had been struck, but it was dead just at the top; where the lower branches touched adjacent trees it was still alive. That connection is what protects trees in forests, otherwise we would see far more lightening damage than there is.

I am constantly aware too that wind loosens and breaks fruits and branches, so it’s not a good idea to walk in the garden at Rimbun Dahan just before a storm hits when the wind has considerable force. A bunch of old coconuts landing on you is not a healthy proposition.

On Friday 13th, we should have been prepared. Our only Shorea sumatrana, one of our first plantings, near the staff houses, was snapped in two by a strong wind. Fortunately it fell away from Effendi’s house towards the garage, but a piece of branch from another tree fell onto the roof of the garage and skewered right through! Some of the trees have extremely heavy wood, and a fall from some height at the right angle is extremely hazardous. We considered leaving it as a natural installation, but that would have been more hazardous to my stores inside!

This is the same tree that recently flowered in a veil of pink. It was one of the first Dipterocarps planted at Rimbun Dahan, and is critically endangered in the wild. Luckily we have recently propagated 10 seedlings from this tree, when Lauren Black drew and painted its botanic features. We were also able to collect several seeds from the fallen branches. I’ll have to plant them away from the buildings and make sure they have structural support. Creepers tie the trees to each other and provide stability as well as grounding them from lightening strike.

 
Landscape design in the tropics has to factor in protecting buildings, as the plants do present danger. Similar to kampong adjacent to forest, you don’t want to be too close: snakes, wild boar, centipedes and monitor lizards have all found their way into our house, and ants are an every day problem, but these are not the only issues. In the tropics, houses are more comfortable away from overhanging trees, and this is where I have an issue with the enveloping nature of the Bali style of planting, the tropical version of an English cottage garden.

Overhanging trees do shade a house, but they don’t make it any cooler. Instead they prevent it from drying out during the day when the sun has full force and from cooling quickly at night. Humidity increases, much to the detriment of the building and things inside. Trees too limit the amount of air movement through a building, and if you want natural ventilation to substitute for air conditioning, trees in close proximity will block the little air flow there is.

Another reason for planting away from buildings relates to viewing the trees. Tropical plants do not have spectacular displays of flowers that one associates with an English garden. Flowers are small and only occasionally do they appear en mass for a dramatic display. In a forest, fragrance is more important to advertise the readiness of flowers for pollination when vistas are blocked all around. A lavish display of blossom would be wasted if it can’t be seen. When considering placing tropical trees to view any flowering, they are better positioned away from the house as flowers are on the outside of the canopy; if a tree is adjacent to a house all you see is its underside and not any display of flowers or changing foliage.

The gardens at Rimbun Dahan surround the buildings, but wherever possible there are spaces between buildings and plants, including those in pots. Early plantings though, like the Shorea sumatrana, were carelessly placed close to houses, only to crash down decades later. I guess too, I never appreciated how big they grow in relation to the domestic scale.

A Lime Butterfly, Papilio demoleus malayanus, was resting on the glass door of Rochelle and Monika’s studio, and was much admired by all. Unfortunately for the butterfly, 5 minutes after it posed for photographs, a cheeky gecko came and ate it.

This, a familiar butterfly of gardens and villages, is one of a group all of which have remarkably similar caterpillars which feed on kinds of citrus. P. demoleus is the commonest: almost every small lime bush seems to have larvae.

The eggs are usually laid upon young leaves; the larvae first resemble bird-droppings, later becoming green with grey oblique markings which effectually disguise them. The pupa, like those of many Papilionid and Pierid butterflies, is able to adapt its colour, within limits, to its surroundings.

Common and widely distributed in S.E. Asia, New Guinea and Australia, this insect is not found in Java, Sumatra or Borneo.

From Common Malayan Butterflies, R. Morrell, Malaysian Nature Handbooks

According to Wikipedia, The Black-thighed Falconet (Microhierax fringillarius) is one of the smallest birds of prey. It is typically between 14 to 18 centimetres long. It can be found in Thailand, Malaysia, Singapore and Indonesia. It breeds in tree holes. It feeds on small birds and insects. The typical habitat is forest, forest edge and wooded open area. Our pair of falconets was photographed while feasting on dragonflies.