27 July 2008

Butterfly Photography at our Local Parks

Butterfly Photography and Watching at our Local Parks
Featuring : Alexandra Hospital Butterfly Trail

About Alexandra Hospital

Alexandra Hospital is a 400-bed hospital located in the West of Singapore. Nestled on an 11 Hectare site, the hospital is a picture of tranquil setting, lined with mostly colonial style buildings built since the late 1930’s. From its humble start in 1971 when it was handed over to the Government of Singapore, the hospital underwent various transformations and enhancements of its medical services to the public.

The hospital was restructured and became a member of the National Healthcare Group on 1 Oct 2000. Under the stewardship of the CEO Liak Teng Lit, the hospital became well known for its innovation and service excellence. Besides the initiatives on the medical and services fronts, the hospital grounds were also attractively landscaped and the colourful Canna bushes welcomed visitors to the grounds of Alexandra Hospital (or AH, as we all know it)

How It all Started

It started with an article which I wrote in the July 2001 issue of Gardenwise, the newsletter of the Singapore Botanic Gardens, featuring butterflies. CEO Liak, who was then a Board Member of the National Parks Board, read the article, and invited me to give a talk at AH during their Clean and Green Week in 2001. He wondered if it was possible for AH to feature more butterfly species than the Singapore Botanic Gardens!

One of his staff, Mrs Rosalind Tan, was assigned to start the butterfly trail at AH. With a little bit of help from some NSS enthusiasts, the landscaping for an open patch of green in the valley between the main blocks of AH and Alexandra Road began. Butterfly host plants as well as nectaring plants were planted in the valley, and paths created around the lush landscaping. With Rosalind's tireless enthusiasm, and her supportive other half, retired architect Tan Wee Lee, and the AH gardeners, the rest, as they say, is history.

After about 2 years, the landscaping with a myriad of butterfly host and nectaring plants worked wonderfully, and Singapore's first free-ranging butterfly trail was born!

Fast forward to 2008. After seven years, the AH Butterfly Trail is still lush, green and full of life. In April 2007, AH recorded its 100th species - a Chestnut Angle. The checklist for AH stands at 101 at the end of 2007. (Links to ButterflyCircle Forums. Please register an account)

Butterfly Photography at the AH Butterfly Trail

The AH Butterfly Trail is an excellent location for fledgling butterfly photographers. On a typical sunny day, there would often be at least 10 species to shoot. Amongst the more common ones are the Blue and Dark Glassy Tigers, as well as the attendant Common Palmfly and Chocolate Pansy. Often seen are the Emigrants - Lemon, Mottled and Orange, the Common Mormon, Lime Butterfly, and Baron. Over the years, the tally of 101 species includes some of the rare Lycaenids and Hesperiids which visit the trail occasionally.

With the host plant Aristolochia acuminata (formerly referred to as tagala), AH Butterfly Trail often features the two butterflies which feed on this plant - the Common Birdwing, and the Common Rose. A unique subspecies, possibly antiphus also flies at this trail. It is always breathtaking to see the large and spectacular black-and-yellow Common Birdwing fly around the trail, and during a good season, up to six individuals can be seen, gliding high above the trail.

The popular spots for butterfly photography are at the sunlit areas where the Common Snakeweed, Lantana and Indian Heliotrope grow. These flowering plants are the favourites for the Glassy Tigers, Grass Yellows and many Skippers.

In the shadier areas of the trail, one can often encounter Skippers like the Chocolate Demon, Paintbrush Swift and the Grass Demon. The flowers of Pagoda Flower, and many other flowering plants along the trail also attract a variety of butterflies to feed on them.

Besides butterflies, the Trail is also home to a rich biodiversity of flora and fauna, and it is not unusual to observe the Web of Life lessons at this trail, where predators and victims of all shapes and sizes inhabit the trail. An observant enthusiast can often see butterflies mating, laying eggs, and a variety of caterpillars in various instars on the host plants at the Trail.

Other Areas for Photography at AH

Beyond the Butterfly Trail, there are also areas which are good for macro photography. Amongst these are the Medicinal Garden, the Eco Pond and all around the lushly landscaped grounds of the hospital.

What the Future Holds

It has been seven years since the start of the Butterfly Trail, and till today, the Trail has its regular weekend photography visitors, each hoping to nail a better shot of a species of butterfly. Moving on, it is sad to note that AH will be moving north to Yishun where the new 550-bed Khoo Teck Puat Hospital is currently under construction. Expected to be completed and fully operational in early 2010, the KTPH will replace AH.

What will happen to the hospital grounds after AH is vacated? It is likely that the hospital will continue to be operational for a few more years thereafter, and beyond 2014, the premises are likely to be redeveloped for other uses. It would be sad to see the AH Butterfly Trail go, as for many butterfly photographers, the Trail was the start of many years of butterfly watching and shooting, having whetted the appetites and enthusiasm of many an avid butterfly photographer.

On the positive side, many other similar trails are being planned or already in existence. The experience and knowledge gained from the experiment with AH has been shared with the National Parks Board, and many parks, park connectors and gardens have been planted with butterfly-attracting plants to increase the butterfly biodiversity in our parks and gardens. One such successful example is the Butterfly Hill at Pulau Ubin. The new KTPH hospital at Yishun will also feature its own butterfly trail around the Yishun Pond. Work has started, and it will be a matter of time before the lush landscaping and tender loving care from Mrs Rosalind Tan and other enthusiasts will re-create a new butterfly trail at the new location.

How to Get There

Getting to the AH Butterfly Trail is quite easy, as it is just off the main road (Alexandra Road), and it is very accessible. Parking is chargeable if you drive, at the prevailing rates that the hospital charges. There is also a cafeteria at AH where you can stop for refreshments after a good session of shooting butterflies at the Trail.

Map of Alexandra Hospital

Text and Photos by Khew SK

19 July 2008

Life History of the Narrow Spark

Life History of the Narrow Spark (Sinthusa nasaka amba)

Butterfly Biodata:
Genus: Sinthusa Moore, 1884
Species: nasaka Horsfield, 1829
amba Kirby, 1878
Wingspan of Adult Butterfly: 25mm
Caterpillar Host Plants:
Eurya acuminata (Theaceae)

Physical Description of Adult Butterfly:
The adults closely resemble adults of Common Tit, a larger and more common species. Above, the male is dark brown on the forewing with deep blue tinge at basal half, and the hindwing is mostly violet blue with a dark brown costal border. The female is dark brown with a white tornal area bearing black spots in the hindwing. Underneath for both sexes, the post-discal line of narrow ochreous brown stripes is mostly continued on the forewing, but broken on the hindwing. A black tornal spot is present in space 2 and another on the lobe of the hindwing, with the tornal area rather sparsely dusted with metallic green scales.

Field Observations of Butterfly Behaviour:
This small species is rather uncommon in Singapore. Sightings have been localized to a few area within the Central Catchment Reserve Area. Encounters with the adults typically take place in dim lighting condition under forest canopy.

Early Stages:
The host plant, Eurya acuminata, is a small tree with lanceolate or ovate-oblong leaves of length 4-9cm. The leaf has finely toothed margin and net-like tertiary veins. The twigs are round and glabrous (finely hairy). The flowers are minute (less than 0.5cm across) and arranged in 2-5 flowered inflorescence, axillary or along leafless twigs. Juice extract of tender leaves is drunk in some parts of the world to relieve dysentery and diarrhoea. Locally, this plant can be found in secondary forest alongside trails within the Central Catchment Reserve Area.

The host plant, Eurya acuminata, pictured with one female Narrow Spark trying to oviposit on the leaf underside

Eggs are laid singly on the a flower bud or on the stem/leaf adjacent to the buds. Each egg is green in color, small (about 0.4-0.5mm in diameter) and circular with a slightly depressed micropylar. The surface is finely sculptured with intersecting ridges. The egg is almost identical to eggs of Rapala species described in the literatures.

A female Narrow Spark ovipositing near a flower bud of the host plant

An egg of the Narrow Spark, about 0.5mm in diameter.

Three days later, the egg hatches with the young caterpillar eating away the upper portion of the egg shell to emerge. Measured at a length of about 0.8-0.9mm, it is cylindrical in shape, sporting long setae (hairs), a large dark brown head capsule and overall pale yellow body.

Mature egg (left), empty egg shell (right)

1st instar caterpillar, newly hatched, length: about 0.8mm

The 1st instar caterpillar bores into a flower bud and eats the developing flower parts within it. It feeds with its head in first, keeping its rear end close to the entrance for ejecting frass outside the bud. Usually the presence of caterpillar "hidden" in a particular hole is given away by tuffs of fine hair at the hole entrance and the presence of frass nearby.

Left to right, a 1st instar caterpillar re-entering a flower bud for its feast, length: 1.2mm

After 2 days of growth and reaching a length of about 2mm, the caterpillar moults to the next instar. Some caterpillars actually moult within a flower bud. The second instar caterpillar has numerous tubercles covering its body with short fine hairs protruding from them. There are small dark brown spots set against a light brown base color. As the caterpillar grows larger, more and more of the posterior end of its body will remain outside the flower bud as it feeds on the goodies within.

2nd instar caterpillar, late in this stage, length:4mm

The 2nd instar caterpillar reaches a length of about 4.5mm, and after 3 days in this stage, it moults again. Keeping a similar appearance as in previous instar, the 3rd instar caterpillar has more prominent dorsal markings with a brown dorsal line. Tubercles lining the body segments in the sub-dorsal and sub-spiracular locations have become enlarged with tuffs of protruding setae. The typical lycaenid nectary organs (both the dorsal nectary organ and tentacular organs) are now discernible. The 3rd instar takes 3 days to complete with the body length reaching about 8.5mm.

3rd instar caterpillar checking out a flower bud, length: 8mm

The 4th (and final) instar caterpillar still has the same dorsal markings as in earlier instars, but the white diamond-shaped prothoracic shield now has prominent black spots at its 4 corners. Initially the body base color is pale brown with the 1st thoracic segment and the anal plate yellowish green. As the caterpillar grows, as depicted in the 3 figures below, the base color changes to yellowish brown and finally to yellow in the first three days of this instar. The sub-dorsal and sub-spiracular rows of tubercles become translucent to transparent in appearance, with some of them assuming a bluish coloration. Furthermore, as the body base color changes to yellow, the 5th abdominal segment also becomes darkened from the sub-dorsal to sub-spiracular area.

4th instar caterpillar, day 1 of 5 in this stage, length: 10mm

4th instar caterpillar, day 2 of 5 late in this stage, 12mm

4th instar caterpillar, day 3 of 5 in this stage, 14mm

The dorsal nectary organ and the tentacular organs on the 7th and 8th abdominal segments respectively are rather prominent in the final instar caterpillar. On the last day of the final instar, copious amount of clear fluid was observed to be excreted from the nectary organs of the shortened and decolorized caterpillar. These functioning nectary organs suggest a strong caterpillar-ant association in the wild.

The anterior segments of a 4th instar caterpillar, the nectary organs are annotated.

After five days of growth and reaching a maximum length of around 14mm in the the final instar, the body of the caterpillar becomes shortened and decolorized caterpillar. Soon it chooses a spot on the leaf surface to remain stationary and becomes a pre-pupatary larva. At this site, it prepares for pupation by spinning a silk girdle and a silk pad to which it attaches itself via cremastral hooks.

A pre-pupa of the Narrow Spark, showing a finished silk girdle securing it to
the leaf surface, also visible is clear fluid from a final purge.

Pupation takes place after 1 day of the pre-pupa stage. The hairy pupa has a shape typical of most lycaenid species, and a length of about 7.5mm. It is light brown dotted with small dark brown specks.

Two views of a pupa of the Narrow Spark.

Seven days later, the pupa becomes darkened in color signaling the imminent emergence of the adult. The uppersides of the forewings become visible through the now transparent pupal skin, allowing one to tell the gender of the soon-to-appear adult. The next day the adult butterfly emerges from the mature pupa.

Two views of mature pupa of the Narrow Spark

A newly eclosed female Narrow Spark resting on a perch

A male Narrow Spark resting on a perch in CCA


I would like to express my gratitude to Prof Hugh Tan of NUS DBS and Ali Ibrahim of Nparks for providing confirmation of the host plant species ID.


  • The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, 4th Edition, Malayan Nature Society.
  • The Butterflies of Hong Kong, M. Bascombe, G. Johnston, F. Bascombe, Princeton University Pres 1999

Text and Photos by Horace Tan

13 July 2008

Butterfly of the Month - July 2008

The Branded Imperial (Eooxylides tharis distanti)

This pretty forest butterfly is always present to greet visitors to the nature reserves of Singapore, never failing to delight nature enthusiasts with its bright orange colouration and long white tails. It is often seen fluttering in the shady understorey and thick vegetation, and rarely moving out to bright sunny areas. The Branded Imperial is local in distribution, but is not uncommon. Frequently, a few individuals are observed, frolicking and chasing each other in shady vegetation.

The wings are blackish brown above, with a white tornal patch on the hindwing. The underside is a reddish orange, with an unmarked forewing, with the hindwings featuring large black submarginal spots on the white tornal area which is fringed by an irregular black line, separating the white tornal patch from the orange area of the hindwing.

The eyes are an opaque jet black, as are the antennae, whilst the butterfly has black-and-white banded legs. There are three pairs of tails on the hindwings, of which the one at vein 2 is the longest, often measuring about 1cm in length.

The Branded Imperial has a short skipping flight, as it flits from perch to perch at usually no more than a metre above the ground. As with many Lycaenidae, the tails and 'eyespots' on the hindwings are believed to function as illusionary decoy to fool predators into attacking the tails rather than the vital part of the butterfly. Indeed, if one is to observe the Branded Imperial at rest, individual sometimes move their hindwings up and down and their tails twirl and move in the light forest breeze, giving it an appearance that the combination of the hindwing eyespots and the tails are the head and antennae of the butterfly.

Occasionally, several individuals can be observed feeding on the sap of young shoots of various species of forest plants, where the butterflies are so busy feeding on the sugary-sweet sap that they even allow observers to touch them!

The Branded Imperial's early stages have been recorded on its preferred host plant, Smilax bracteata, a forest climber which is considered a "pest" and a threat to the trees and large bushes onto which the vine climbs and slowly suffocates.

Text by Khew SK ; Photos by Khew SK, Mark Wong and James Chia