22 November 2014

Butterfly of the Month - November 2014

Butterfly of the Month - November 2014
The Malayan Eggfly (Hypolimnas anomala anomala)

"It's beginning to look a lot like Christmas..." as the song goes. The eleventh month of 2014 is upon us, as shopping malls and office buildings in Singapore get decorated in anticipation of the year-end holidays and Christmas season. Many shopping malls are getting in on the act early to take advantage of the end of school season and people who would like to do their Christmas shopping early. Even the theme at our Gardens by the Bay already feature Christmas decor and lights to mesmerize its visitors with the colours of the season.

It's been an interesting year of ups and downs, both in the local and global scenes, as Singapore looks ahead towards celebrating its 50th year of independence since 1965. The year 2015 looks like it's going be a pretty busy year for Singapore with many commemorative celebrations and events planned by numerous organisations, both from the public and private sectors. Even ButterflyCircle is also planning on a special 'present' for Singapore's 50th birthday, but let's leave that for later. ;)

On the butterfly conservation and research front, we are encouraged to see more people interesting in butterflies - setting up butterfly gardens and sanctuaries, as well as learning more about butterflies through observing them and photographing them. As the Lee Kong Chian Natural History Museum, one of the region's first custom-designed building for a natural history museum readies itself for completion, several exciting initiatives and projects, in collaboration with ButterflyCircle, are in the works.

A typical example of form-nivas of the Malayan Eggfly

ButterflyCircle members have continued to contribute to conservation initiatives and promoting butterfly-friendly projects in collaboration with the National Parks Board. In support of Ubin Day, ButterflyCircle will be conducting a butterfly watching and photography session next Sunday, 30 Nov 2014. The registration for participants is now closed, and we thank all the interested parties for registering and joining us. Weather permitting, we hope that you will have an enjoyable morning at Butterfly Hill on Pulau Ubin!

Upperside of a form-anomala of the Malayan Eggfly

This month, our feature butterfly is the Malayan Eggfly (Hypolimnas anomala anomala). This low-profile and relatively sombre coloured butterfly doesn't usually create much excitement amongst butterfly watchers, when compared to its more colourful and attractive cousins. In fact, it is often mistaken for one of the drab "Crows" from the Danainae family, due to its close resemblance to its distasteful models.

A form-anomala of the Malayan Eggfly feeding on the flowers of the Red Leea

The Malayan Eggfly displays mimetic behaviour, in that it mimics the Crows for protection against predators. It also flies in an unhurried and slow manner, copying the flight of the Crows to fool predators to avoid them as they would for the distasteful Danainaes. From the number of mis-identifications of this species by beginners and casual nature enthusiasts, we can almost conclude that the Malayan Eggfly is a passable mimic of the Crows (at least from the human perspective!).

The Malayan Eggfly is relatively common in Singapore. Seasonally, several individuals can be observed together at various locations, particularly in the vicinity of its caterpillar host plant, Pipturus argenteus, a secondary forest bush that grows quite commonly in the forested areas of Singapore.

A form-nivas with reduced white markings on the hindwing

The species is observed to display territorial behaviour - particularly the males. Individuals select favourite perches amongst shrubbery and low foliage, and perch with wings held upright. Whenever an 'intruder' breaches its domain, it will fly out and try to 'attack' the newcomer. At other times, it returns repeatedly to its favourite perches even when disturbed.

In the typical form, the Malayan Eggfly is reddish brown on the upperside, with a series of post-discal and submarginal white spots on both wings. The underside is usually darker and bears the white spots as on the upperside. The species is subject to considerable variation in the extent of additional white markings on the hindwings, although two distinct forms are documented for this species.

Form-anomala is the typical brown form where the hindwing post-discal area is unmarked, both on the upper- and undersides. This form is the more commonly observed one, and is quite widespread in distribution, from urban parks and gardens to the forested sanctuary of the nature reserves.

Typical form-nivas with prominent white post-discal patches of varying degrees on the hindwing on both the upper and undersides

The other form, which is slightly less encountered, features a series of white post-discal streaks on the hindwings. This is form-nivas. Between the two forms, is a wide spectrum of variations from totally no postdiscal markings, to a few obscure streaks, to a prominent white patch on the hindwings.

A female variant with iridescent blue forewings resembling a Striped Blue Crow

The two forms are passable mimics of the Danainae species that are also found in Singapore - Striped Blue Crow (for form-anomala) and Lesser Striped Black Crow (for form-nivas). However, not infrequently, a third "form", with iridescent blue forewings on the upperside, is seen. This variant is usually female, featuring the attractive blue forewings and we believe it mimics the male Striped Blue Crow. Ecologically, it also makes sense that the female has a series of alternative mimetic strategies to ensure a higher chance of survival to prolong its lifespan to be able to lay as many eggs as possible before it falls prey to a predator or dies of natural causes. However, why this is not considered a different form or documented in any research paper as such, is still not fully understood.

A female Malayan Eggfly standing guard over her eggs

Speaking of egg-laying, the Malayan Eggfly displays a very unique behaviour where the female, after ovipositing from anything between 50 to 100 eggs on the underside of the leaf of its host plant, "stands guard" over the eggs. This behaviour has been documented by researchers and papers have been written about it, but it is not really known why the female does that, because a butterfly does not possess the means nor arsenal of offensive weaponry to fend off any potential predators of her eggs.

Another shot of a form-anomala female Malayan Eggfly standing guard over her future babies

In some instances, the female stands guard over her eggs until the first instar caterpillars hatch and start eating the leaf. The adult butterfly, in at least two of our observations, died in that position, "protecting" her eggs till her last breath. In a controlled environment on one occasion, we physically removed the female butterfly from her perch, only to see it fly back the moment it was released, back to stand guard over her progeny!

The Malayan Eggfly is partial towards human sweat as can be seen here, feeding on a sweaty camera body and a sweaty finger.  The top photo shows the species puddling at sandy streambanks

The Malayan Eggfly has also been observed puddling at sandy streambanks and muddy footpaths. It also has a liking for human sweat and there have been instances where it stays on the hands and arms of ButterflyCircle members, sipping sweat.

A mating pair of form-anomala Malayan Eggfly

The life history of the Malayan Eggfly has been fully documented here in Singapore, feeding on the caterpillar host plant, Australian Mulberry (Pipturus argenteus). The detailed life history of this species can be found here.

Text by Khew SK : Photos by Sunny Chir, Goh EC, Huang CJ, Koh CH, Khew SK, Loke PF, Jonathan Soong, Horace Tan, Nelson Ong and Anthony Wong.

15 November 2014

Life History of the Full Stop Swift

Life History of the Full Stop Swift (Caltoris cormasa )

Butterfly Biodata:
Genus: Caltoris Swinhoe, 1893
Species: cormasa Hewitson, 1876
Wingspan of Adult Butterfly: 32-34mm
Caterpillar Local Host Plants: Ottochloa nodosa (Poaceae), Panicum maximum (Poaceae, common name: Guinea Grass), Ischaemum ciliare (Poaceae, common name: Smut Grass).

Physical Description of Adult Butterfly:
On the upperside, the wings are dark brown with hyaline spots in spaces 2,3 and 4, subapical spots in spaces 6 and 7 and two cell spots in the forewing. The upper cell spot is typically either absent or small in comparison to other Caltoris spp. On the underside, the wings are ferruginous brown, usually with a purplish tinge.

A close-up view of the forewing upperside, showing two small cell spots of a Full Stop Swift.

The upperside view of a newly eclosed Full Stop Swift. The upper cell spot is absent  while the lower cell spot is small.

A Full Stop Swift visiting flower in a wasteland.

Field Observations of Butterfly Behaviour:
The Full Stop Swift is moderately common in Singapore. The adults have been sighted in multiple locations including forested areas, wastelands, urban parks and gardens across the island. The adults fly with a swift, strong and darting flight.

08 November 2014

Butterflies of Pulau Ubin

Butterflies of Pulau Ubin
Butterfly Hill @ Pulau Ubin

Aerial view of Butterfly Hill @ Pulau Ubin - © National Parks Board

Pulau Ubin, an offshore island of Singapore of about 10.2 sqkm, is often considered the "last frontier" of rural ambience and rich biodiversity in Singapore. Local Malays once called it "Pulau Batu Ubin" or Granite Stone Island. In the past this small island supplied the local construction industry with granite and sand, from which coarse aggregates and the sand were used to construct roads, manufacture concrete and other building materials. The granite was also used to make floor tiles, or Jubin as it was called in Malay.

A map of Pulau Ubin - © National Parks Board

Today, the 7km long by 2km wide island is a favourite weekend destination for adventure lovers and nature enthusiasts taking a short bumboat ride from the Changi Ferry Terminal. The island is known for its rich biodiversity and rustic environment to which many weekend visitors flock to get away from Singapore's hectic urban lifestyle.

On the bumboat back from Ubin with senior government officials and nature enthusiasts

In early 2014, the Ministry of National Development, led by Minister of State Desmond Lee, visited Pulau Ubin with a group of nature enthusiasts, heritage experts and community leaders. The visit was part of the wider plan to initiate a conversation with Singaporeans on how we can all play a part to sensitively enhance the natural environment of Pulau Ubin, which was announced by Mr Desmond Lee in Parliament in March 2014.

A group photo of Friends of Ubin Network taken at Singapore Botanic Gardens

Subsequently, the Friends of Ubin Network (FUN) was set up to continue to engage the stakeholders whilst a public feedback portal and even an Ubin Symposium was organised to openly discuss possible options for Ubin. There have been numerous media articles and blog articles discussing what different groups of people want for Ubin.

Blue Glassy Tiger (Ideopsis vulgaris macrina) - a "resident" species at Butterfly Hill

On 30 Nov 2014, a public event to celebrate Pulau Ubin, will be resurrected by Ria Tan and Grant Pereira.  The event, known as Ubin Day, was previously held in 2002 and 2003, and this will be the 3rd instalment of this event, featuring different activities by various groups in many parts of the island. The event's objective is to introduce the diversity of activities that can be enjoyed by the general public on this little island, and to showcase the amazing biodiversity that we have on Ubin.

A peep at the Butterfly Hill during earthworks back in 2005

Let's come back to Pulau Ubin's Butterfly Hill. In 2005, the Jelutong Campsite was created out of a piece of wasteland reclaimed from the sea during past granite quarrying operations. Within the campsite sits Butterfly Hill – a knoll created specially to conserve and showcase butterflies. Back then, I worked with NParks' staff, Robert Teo, Choi Yook Sau, Jacky Soh and How Choon Beng to build up Butterfly Hill from scratch. I remember vividly when the hill was completely wiped clean except for a solitary tree, and the hill was just covered with red earth.

Black Veined Tiger (Danaus melanippus hegesippus) - a regular visitor at Butterfly Hill

Fast forward to 2014, it's been almost 10 years in the making, and the Butterfly Hill continues to be a good place to observe butterflies, yielding the occasional surprise in terms of rare species. Over the period since the Butterfly Hill was designed and planted with butterfly host and nectaring plants, we have recorded over 150 species (and counting!). On a typical day, one can expect to be greeted by the resident Plain Tigers, Blue Glassy Tigers, Pea Blues, Great Eggflies, Common Birdwings and others. A half day butterfly watching outing should easily yield about 20 different species.

Common Line Blue (Prosotas nora superdates) feeding on Bidens flower at Butterfly Hill

Amongst the uncommon butterflies that have been spotted and photographed at Ubin's Butterfly Hill are :

Mangrove Tree Nymph (Idea leuconoe chersonesia) - This large Danainae is very rare, previously known only from Pulau Tekong. This individual was photographed at Butterfly Hill recently.

Malayan Birdwing (Troides amphrysus ruficollis) - A large and showy Birdwing, this species was first recorded in Singapore from a caterpillar discovered at Alexandra Hospital's Butterfly Trail. This species was seen on Butterfly Hill and there have been subsequent sightings in the past year.

Great Mormon (Papilio memnon agenor) - This large swallowtail frequents Butterfly Hill because its caterpillar host plant, Pomelo (Citrus grandis) is cultivated here.

Lesser Striped Black Crow (Euploea eyndhovii gardineri) - This Crow is uncommon and often encoutered singly. Butterfly Hill is one location where this species is observed quite regularly.

Dwarf Crow (Euploea tulliolus ledereri) - The Dwarf Crow is thus far known reliably only from Pulau Ubin. Whilst it was previously seen regularly at Butterfly Hill, it has become rarer and not often seen in the past two years.

Bamboo Tree Brown (Lethe europa malaya) - A shy and skittish shade lover, this species is regularly seen amongst the bamboo clumps at Butterfly Hill.

Forest Hopper (Astictopterus jama jama) - This elusive skipper has regularly been spotted at Butterfly Hill usually flying rapidly amongst the low shrubbery.

Conjoined Swift (Pelopidas conjunctus conjunctus) - This large and fast-flying skipper has been observed at Butterfly Hill on several occasions by ButterflyCircle members.

Plain Palm Dart (Cephrenes acalle niasicus) - This skipper, though not often spotted, has been seen several times at Butterfly Hill, particularly when there are flowering Syzygiums.

So when you visit Pulau Ubin's Butterfly Hill, do look out for some of these rarities, and we hope that you can also add more to the checklist of butterflies on Butterfly Hill by spotting other new species!

On 30 Nov 2014's Ubin Day, ButterflyCircle members will be on site to share tips on butterfly watching and photography. For those who are keen to join us, please sign up here.  We look forward to an enjoyable morning with nature's flying jewels!

Text by Khew SK : Photos by Brian Goh, Khew SK, Simon Sng, Jonathan Soong, Anthony Wong, Yong Wei Hoong

07 November 2014

Butterflies Galore! : Bamboo Tree Brown

Butterflies Galore!
The Bamboo Tree Brown (Lethe europa malaya)

The genus Lethe which features some very rare butterflies in Malaysia and Thailand, is represented by only one species in Singapore. This is Lethe europa malaya or the Bamboo Tree Brown. Its common name obviously suggests that the butterfly is associated with bamboos - its caterpillars feed on certain varieties of bamboo in Singapore. It is a shy butterfly, alert and skittish, and is often found lurking at low level amongst bamboo clumps.

The underside of the Bamboo Tree Brown features cryptic markings and an attractive series of lilac ocelli on the wings. This individual was photographed by ButterflyCircle member Loke PF at Butterfly Hill on Pulau Ubin.

01 November 2014

Life History of the Lemon Emigrant

Life History of the Lemon Emigrant (Catopsilia pomona pomona)

Butterfly Biodata:
Genus: Catopsilia Hübner, 1819
Species: pomona Linnaeus, 1775
Subspecies: pomona Linnaeus, 1775
Wingspan of Adult Butterfly: 50-70mm
Caterpillar Local Host Plants: Senna fistula (Fabaceae, common name: Golden Shower), Senna siamea (Fabaceae, common name: Kassod Tree, Siamese Cassia).

A female Lemon Emigrant, -f. pomona.

Two male Lemon Emigrants, -f. alcmeone.

A male Lemon Emigrant, -f. hilaria.

Physical Description of Adult Butterfly:
Lemon Emigrant comes in a number of  forms for both sexes, but generally they are moderately large with wing upperside appearing in either white or yellow and black-bordered on the costa and termen of the forewing. There are two groups of forms; namely the 'crocale' group and the 'pomona' group.

  • The 'crocale' group is characterized by having the upperside of antennae black, and the absence of silvery spots at cell-ends on the underside. The male -f alcmeone is mostly white above but yellow in the basal third of the wings and thinly bordered at the forewing apex. The females could appear in the jugurtha or the crocale form. The -f jugurtha is creamy white above with yellow wing base and black border on the forewing costa and termen of both wings. It has a series of black submarginal markings and a black spot at cell-end on the forewing. The -f crocale has a broad black distal border with a series of whitish spots embedded on both wings.
  • The 'pomona' group is characterized by having the upperside of antennae red and the presence of red-ringed silvery spots at cell-ends on the underside. The male -f hilaria has similar upperside as the male -f alcmeone but with lesser extent of basal yellow area. The females could appear in the pomona, catilla or the nivescens form. The -f pomona has yellow wings with reduced black border and markings while -f nivescens is similar but with whitish wings. The -f catilla has large reddish patches on the underside.

A female Lemon Emigrant, -f. jugurtha.

A female Lemon Emigrant, -f. crocale.

A female Lemon Emigrant, -f. catilla.