Extinction – what it means for birds in Singapore

Extinction is an evocative word, with some of the world’s most iconic birds such as the Dodo Raphus cucullatus and the Passenger Pigeon Ectopistes migratorius having achieved infamy for the dubious distinction of belonging to this category. Though the term often implies a sense of permanent loss, there are scenarios where extinction is not forever.

There are a few ways to think of the term ‘Extinct’.

The most commonly understood definition of extinction describes a complete global disappearance of a species. In Southeast Asia, no bird has been officially regarded as Extinct by the International Union for the Conservation of Nature (IUCN), though some species such as the Javan Lapwing Vanellus macropterus almost certainly are. The IUCN requires the criteria—exhaustive surveys in known and/or expected habitat, at appropriate times (diurnal, seasonal, annual), throughout its historic range have failed to record an individual—to be satisfied before concluded that a species is Extinct. This is to prevent a loss of directed conservation attention for a species that may actually be very rare rather than gone forever.

A prime example of this would be the recent extinction declaration of the Ivory-billed Woodpecker Campephilus principalis, only made after 77 years after the last confirmed sighting of this conspicuous bird. Such long lag times between last sightings of a species and a formal extinction declaration is not uncommon, especially is species that have historically had large geographic distributions.

Another category is species that are Extinct in the Wild, with all known populations of the species known only from captivity. No birds from the region officially fall into this category, though the newly split Javan Pied Starling Gracupica jalla and Javan Green Magpie Cissa thalassina may qualify with further research.

In both cases, the declaration of extinction is fairly clear-cut. If the bird can no longer be found in the wild, then it will naturally qualify for one of the two categories. However, it is when we begin to incorporate national boundaries into definitions of extinction where things begin to get hazy.

Local extinction describes a scenario where a species is extinct, or no longer occurs, within a specific portion of its geographic range. In many cases, a species may entirely vanish from a country—a situation which we describe as extirpation. Many bird species are extirpated from Singapore. For instance, both the Great Slaty Woodpecker Mulleripicus pulverulentus and Moustached Babbler Malacopteron magnirostre have not had breeding populations in the country for decades (Wang & Hails, 2007). In these cases, extirpation describes a situation where a bird is no longer a Resident Breeder; even though occasional individuals may stray into our shores from elsewhere. The lack of a breeding population precludes them from being considered re-established.

Moustached Babbler in Taman Negara, Pahang. Photo Credit: Keita Sin
Moustached Babbler in Taman Negara, Pahang. Photo Credit: Keita Sin

Record Committees (RCs) are often the local authority for declaring a bird nationally extinct. However, since national boundaries do not present actual barriers to the movement of birds, this task is much more complex than it first appears. Birds that show up unexpectedly could represent a hidden, breeding population of a very rare species or merely visitors from across the border—how does one make a case either way?

Great Slaty Woodpecker in flight, Taman Negara, Pahang. Photo Credit: Keita Sin
Great Slaty Woodpecker in flight, Taman Negara, Pahang. Photo Credit: Keita Sin

In complex cases such as this, members of the RC will have to evaluate records on a case-by-case basis, taking into account the movement and breeding ecology of the species. Many RCs additionally comprise multiple people, so as to utilise a broad swathe of expertise instead of relying entirely on the knowledge of single individuals, whose judgment may be clouded by various biases.

Let us use the previously mentioned Great Slaty Woodpecker and Moustached Babbler as examples.

Great Slaty Woodpecker perches on the side of the tree in Bukit Timah Nature Reserve. Photo Credit: Dillen Ng
Great Slaty Woodpecker perches on the side of the tree in Bukit Timah Nature Reserve. Photo Credit: Dillen Ng

In 2018, a single, Great Slaty Woodpecker was sighted within Singapore’s central forests, staying for only a short while before disappearing. Though the identification of the bird is without doubt, Great Slaty Woodpeckers are conspicuous and noisy birds (Eaton et al., 2021) — it is unlikely that an undetected population has persisted unnoticed on a small island. In addition, large woodpeckers are known to move large distances when searching for suitable foraging locations (Ogasawara et al. 1994; Garmendia et al., 2006). A single bird flying the comparatively short distance from Johor to Singapore would be unremarkable when these woodpeckers are known to fly much greater distances. As such, taking the collective evidence into account makes us suspect that the Great Slaty Woodpecker presents a case where the bird is merely a visiting individual and not part of a larger, undetected population on the island.

Moustached Babbler at Panti Forest. Photo Credit: Francis Yap

However, the ecology of the Moustached Babbler and other understory babbler species such as the Fluffy-backed Tit-babbler Macronus ptilosus is far different. Anyone who has searched for babblers can attest to their penchant for hiding in thick cover and their reluctance to move into the open. This trait suggests that most babblers do not often move across large landscapes without forest cover (Yong, 2006). In addition, the relatively short, rounded wings of most understory babblers indicate that they are poor fliers and unlikely to undertake long-distance movements (Desrochers, 2010; Hermes et al., 2016). As such, if a population of a presently unrecorded babbler species were suddenly re-discovered in Singapore, we would not suspect that these birds were visitors from abroad. However, if these birds were encountered in a site that was regularly birded, we might suspect that these birds were recent releases/escapees. Babblers are highly vocal birds with distinctive calls and would surely have been recognised by local birders had they been present as a breeding population (Eaton et al., 2021).

The Fluffy-backed Tit-babbler is an understory species that is not known to undertake long-distance movements. This individual is from Lenggor, Johor. Photo Credit: Keita Sin

As you can see, nothing is ever quite so clear cut!

These examples offer some insight into the thought processes that we might undertake when confronted by new records. Though it is a rather complex and multifaceted process, we hope that this article makes what seems like a rather opaque and fuzzy process much more understandable!

References

Desrochers, A. (2010). Morphological response of songbirds to 100 years of landscape change in North America. Ecology 91: 1577–1582. doi: 10.1890/09-2202.1

Eaton, J. A., van Balen, S., Brickle, N. W., & Rheindt, F. E. (2021). Birds of the Indonesian Archipelago: Greater Sundas and Wallacea (Second Edition). Lynx Edicions, Barcelona.

Garmendia, A., Cárcamo, S., & Schwendtner, O. (2006). Forest management considerations for conservation of black woodpecker Dryocopus martius and white-backed woodpecker Dendrocopos leucotos populations in Quinto Real (Spanish Western Pyrenees). In Forest Diversity and Management (pp. 339-355). Springer, Dordrecht. Link

Hermes, C., Döpper, A., Schaefer, H. M., & Segelbacher, G. (2016). Effects of forest fragmentation on the morphological and genetic structure of a dispersal-limited, endangered bird species. Nature Conservation16, 39. Link

Ogasawara, K., Izumi, Y., & Fujii, T. (1994). The status of black woodpecker in Northern Tohoku District, Japan. Journal of the Yamashina Institute for Ornithology, 26(2), 87–98. Link

Extinction – what it means for birds in Singapore

Yong, D. L., (2006). Preliminary list of larger vertebrates in Panti Forest Reserve, South Johore. Singapore Avifauna, 20(1): 26–35. Link

 

 

 

 

 

 

An Indonesian Archipelago Wishlist: Birds to Look Out For

The recent sighting of the Javan Plover Charadrius javanicus at a reclaimed site northeast of Singapore island was exciting yet unsurprising. Exciting because it was a first for Singapore and continental Southeast Asia that caught everyone off guard (then again, none of us are really prepared for megas!) and unsurprising because this is a species whose range has been slowly expanding over the years (Iqbal et al., 2011; Eaton et al., 2021). The appearance, and likely breeding of this species is highly relevant to recent changes in regional avifauna, especially when taking into account the first breeding records for the Pied Stilt Himantopus leucocephalus and Black-winged Stilt H. himantopus that were documented at the same site in 2019 and again this year, respectively.

Apart from the Javan Plover, several other species traditionally known to be from the Indonesian Archipelago (that comprises Sumatra, Borneo, Java and other Indonesian islands west of the Wallace Line) could potentially be found in Singapore and the neighbouring regions. Here are the distinguishing features of the Javan Plover and seven other species readers can keep an eye out for!

Javan Plover Charadrius javanicus

This species closely resembles the Kentish Plover, a locally uncommon migrant. Features including warm buff ear-coverts and relatively heavier bill and longer legs point to the Javan Plover. For those keen to learn more, detailed distinguishing features are described in Iqbal et al. (2013). Other regular plovers in Singapore can be distinguished by a combination of several other features. Lesser and Greater Sand Plovers have incomplete white-bands on their neck, Malaysian Plover have more “sandy-looking” upperparts, and White-faced Plover has a plain looking face as its name suggests.

Wandering Whistling Duck Dendrocygna arcuata

Although this species used to be an uncommon introduced species (Wang & Hails, 2007), the last local sighting was in 2016 (eBird) and the feral population has likely crashed for good. Being highly dispersive, wild birds could possibly wander here in due time. In fact, there is a record from Perak, Malaysia, that may conceivably be of wild provenance (but note that the current status of this species in Peninsula Malaysia is also introduced). It can be distinguished from the locally uncommon Lesser Whistling Duck by its lack of yellow eye ring and distinct white flanks.

Sunda Teal Anas gibberifrons

A species that seems to be undergoing a rapid range expansion across Borneo, Sulawesi and Sumatra (Eaton et al., 2016; 2021; Iqbal, 2016; MNSBCC Records Committee, 2016). With records in Sumatra not too far from Singapore, this funny looking duck might make its way here in the near future. It is much darker and browner than the local Whistling Ducks, with a distinct bulge on the male’s forehead. It prefers brackish water although other wetland habitats are also possible sites to look out for this species. Although various breeds of domestic ducks have been released in Singapore, these typically look more Mallard-like, with variable amount of colouration on their heads and wingpanels. Having said that, most if not all wild ducks in Singapore are typically worth celebration, so if in doubt of identification, it’s best to share the sighting for confirmation.

Black-backed Swamphen Porphyrio indicus

Swamphen taxonomy is rather incongruent, with much left to be discovered (Garcia-R & Trewick, 2015; Callaghan et al., 2020; Eaton et al., 2021; Gill et al., 2021). Records from Singapore are thought to be the Grey-headed Swamphen viridis (Wang & Hails, 2007; Callaghan et al., 2020), but possible integrades have been recorded before locally (Wells, 1990). The distribution of the Black-backed Swamphen is also contentious especially on Sumatra, with the two forms likely mixing (Wells, 1999; Taylor, 2020; Eaton et al., 2021). The Grey-headed Swamphen is another species struggling to survive in Singapore – a common theme for local waterbirds – and was last seen in 2018 (eBird). But if you do happen to see one, be sure to check its back colour. Black-backed Swamphen can be distinguished by having darker upperparts and face.

Australasian Grebe Tachybaptus novaehollandiae

The Australasian Grebe is capable of undertaking overwater dispersals (Llimona et al., 2020). Recent new records from Sulawesi and southern Sumatra (Eaton et al., 2016; Eaton et al., 2021) suggest a possible range expansion underway. Its habitat requirements are similar to the locally rare Little Grebe Tachybaptus ruficollis from which it can be distinguished by its darker neck and ear coverts. Given that the Little Grebe is already struggling to survive in Singapore at the moment, the chances of the Australasian Grebe breeding here like the plovers did are probably low, but they’re certainly worth looking out for.

Little Black Cormorant Phalacrocorax sulcirostris

Another species that seems to be experiencing a spread across the Sumatran coast (Eaton et al., 2021). Waterbodies – both coastal and inland – are potential locations to find this species. Locally, escaped individuals of the Great Cormorant and Little Cormorant have been documented (Wang & Hails, 2007). There were apparently two local records of the Little Black Cormorant as well in August and September 1993 (Oriental Bird Club, 1994; Lim, 2009). Assessing the provenance of cormorants can be a challenge in Singapore so do try to obtain high quality images of them (especially the legs) if you find one.

Little Egret Egretta garzetta nigripes

Knowledge on the distribution of this taxon in our region is far from ideal. Present from Indonesia through eastern Australia, it seems to be spreading across Sumatra (Iqbal, 2012; del Hoyo et al., 2020; Eaton et al., 2021). Their local status varies from “uncommon”, “sparing” to “probable” (Wang & Hails, 2007; Robson, 2014; Puan et al., 2020) and there is still much for us to document. Possible integrades have been seen in Singapore too. Various bare part colouration distinguishes this taxon apart from the locally common migrant Little Egret garzetta (Bakewell, 2019), perhaps most distinct among them being their toe colour – black in nigripes, yellow in garzetta in breeding plumage (images 14 & 15). However, caution should be taken during identification as juveniles and non-breeding garzetta can have duller feet and mud can affect feet colour (Robson, 2014).

 

Sacred Kingfisher Todiramphus sanctus

This species breeds in Australia and is a highly likely contender for showing up on Singapore given that it is an Austral migrant to Borneo and Indonesia, similar to the Horsfield’s Bronze-cuckoo Chrysococcyx basalis. Multiple people have claimed an encounter with this species in Singapore and it is also listed to be present in Robson (2014). However, none of the records have been adequately substantiated and a record from Thailand in February 2019 (Round et al., 2020) is the only formal record in our region thus far. The Sacred Kingfisher can be distinguished from the Collared Kingfisher T. chloris by its turquoise upperparts (as opposed to blue), smaller overall size and bill, and buff wash on its lores and flanks. Care is required in distinguishing this species from immature Collared Kingfishers as they can show some buff wash as well, but typically with scalloped plumage on their breast.

Acknowledgements

Huge thanks to Dave Bakewell, James Eaton and Khaleb Yordan for identification discussions on the Javan Plover identification online, as well as others we had offline. I would also like to express my gratitude to Frankie Cheong for documenting and sharing pictures of Singapore’s first Javan Plover, to the Singapore Birds Project team (Dillen, Francis, Movin, Raghav, Sandra) for comments on this article and to the following for sharing their excellent photos: Dillen Ng, Geraldine Lee, Goh Cheng Teng, Khaleb Yordan and Lim Hong Yao.

Literature Cited

Bakewell, D. (2019). The Chinese Egret Egretta eulophotes: identification revisited. BirdingAsia, 31, 14-23.

Callaghan, C. T., Pranty, B., Pyle, P., & Patten, M. A. (2020). Gray-headed Swamphen (Porphyrio poliocephalus), version 1.0. In Rodewald, P. G. & Billerman, S. M. (Eds.), Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.purswa3.01

del Hoyo, J., Martínez-Vilalta, A., Motis, A., Collar, N., Kirwan, G. M., & Christie, D. A. (2020). Little Egret (Egretta garzetta), version 1.0. In Billerman, S.M., Keeney, B.K., Rodewald, P.G. & Schulenberg, T.S. (Eds.), Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.litegr.01

Eaton, J. A., van Balen, S., Brickle, N. W., & Rheindt, F. E. (2016). Birds of the Indonesian Archipelago: Greater Sundas and Wallacea. Lynx Edicions, Barcelona.

Eaton, J. A., van Balen, S., Brickle, N. W., & Rheindt, F. E. (2021). Birds of the Indonesian Archipelago: Greater Sundas and Wallacea (Second Edition). Lynx Edicions, Barcelona.

Garcia-R, J. C., & Trewick, S. A. (2015). Dispersal and speciation in purple swamphens (Rallidae: Porphyrio). The Auk: Ornithological Advances132(1), 140-155. Link: https://academic.oup.com/auk/article/132/1/140/5149144?login=true

Gill, F., Donsker, D. & Rasmussen, P. (Eds). (2021). IOC World Bird List (v11.2). doi:10.14344/IOC.ML.11.2

Iqbal, M., Febrianto, I., & Zulkifli, H. (2011). The occurrence of the Javan Plover Charadrius javanicus in Sumatra, Indonesia. Wader Study Group Bulletin, 118(2), 131-133.
Link: https://www.researchgate.net/publication/293205017_The_occurrence_of_the_Javan_Plover_Charadrius_javanicus_in_Sumatra_Indonesia

Iqbal, M., Nurza, A. & Giyanto. (2012). Breeding Records of Little Egret Egretta garzetta in Sumatra, with notes on the occurence of race E. g. garzettaKukila16, 59-63.
Link: https://www.researchgate.net/publication/315912527_Breeding_Records_of_Little_Egret_Egretta_garzetta_in_Sumatra_with_notes_on_the_occurence_of_race_E_g_garzetta

Iqbal, M., Taufiqurrahman, I., Gilfedder, M., & Baskoro, K. (2013). Field Identification of Javan Plover Charadrius javanicusWader Study Group Bulletin120(2), 96-101.
Link: https://www.researchgate.net/publication/262562330_Field_identification_of_Javan_Plover_Charadrius_javanicus

Iqbal, M. (2016). Status of Sunda Teal Anas gibberifrons in South Sumatra. Kukila19, 30-33.
Link: https://www.researchgate.net/publication/316075498_Status_of_Sunda_Teal_Anas_gibberifrons_in_South_Sumatra

Lim, K.S. (2009). The Avifauna of Singapore. Nature Society (Singapore), Singapore.

Llimona, F., del Hoyo, J., Christie, D. A., Jutglar, F., Garcia, E. F. J., & Kirwan, G. M. (2020). Australasian Grebe (Tachybaptus novaehollandiae), version 1.0. In del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (Eds.), Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.ausgre1.01

MNSBCC Records Committee. (2016). Latest News 22 November 2016. MNSBCC Records Committee. Retrieved 28 August 2021 from https://sites.google.com/site/mnsbccrecordscommittee/Home/latest-news

Oriental Bird Club. (1994). From the field. Oriental Bird Club Bulletin, 19, 65-67.
Link: https://www.biodiversitylibrary.org/item/253243#page/69/mode/1up

Puan, C.L., Davison, G. & Lim, K.C. (2020). Birds of Malaysia. Lynx Edicions, Barcelona.

Robson, C. (2014). Field guide to the birds of South-East Asia (Second Edition). Bloomsbury Publishing, London.

Round, P D., Jahan, I., Thompson, P. & James, D. J. (2020). Mainland Asia’s first record of Sacred Kingfisher Todiramphus sanctus. BirdingAsia, 34, 123-127.

Taylor, B. (2020). Black-backed Swamphen (Porphyrio indicus), version 1.0. In Rodewald, P.G. (Eds.), Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.purswa4.01

Wang, L. K., & Hails, C. J. (2007). An annotated checklist of the birds of Singapore. Raffles Bulletin of Zoology15, 1-179.
Link: https://lkcnhm.nus.edu.sg/wp-content/uploads/sites/10/app/uploads/2017/04/s15rbz001-179.pdf

Wells, D.R. (1990). Malayan Bird Report: 1986 and 1987. Malayan Nature Journal, 43, 172-210.

Wells, D. R. (1999). The birds of the Thai-Malay peninsula (Vol. 1). Academic Press, London.

Nesting Malaysian Plovers

By Goh Cheng Teng
Edited by Keita Sin & Lester Tan

The Malaysian Plover Charadrius peronii is a small shorebird that inhabits coastal sandy areas and rocky shores. It is the only resident breeding plover in Singapore island and can be reliably found along the man-made seawall at Marina East. They are classified globally as Near Threatened (BirdLife International, 2017) and locally as Threatened (Lim, 2009).

A Chick!

On the morning of Sunday 27 June 2021, Lester Tan and I were walking along the Marina East seawall when we were halted by a soft twik from a male Malaysian Plover to our front. This was highly unusual as the Malaysian Plovers at Marina East do not typically vocalise, preferring instead to scurry away in silence.

With this thought at the back of our minds, we started scanning the area, locating a female Malaysian Plover slightly behind and below us in short order. We soon spotted movement from the female’s direction, which turned out to be an extra set of legs belonging to a very new Malaysian Plover!

As we approached slowly for better photographs, the female Malaysian Plover brooded the chick for a while (image 1) before running off, presumably to distract us from the chick. We kept our distance and the chick waited a while before getting up to follow the parent (image 2).

Growing up

Over the next three Sundays, we revisited Marina East to document the chick’s progress (image 3). Each time, we were first greeted by the soft twik of the male Malaysian Plover a distance away from where we would eventually find the female and the chick.

On 4 and 11 July, the weather over Singapore was rainy and the chick was regularly brooded by an adult, probably to aid in regulating body temperature (image 4). By 18 July, the chick had grown discernibly larger. While we did not witness brooding, it still sought cover from threats. Chicks of the Malaysian Plover are precocial and are never fed by parents (Yasué & Dearden, 2008) but we also could not observe any feeding behaviour.

Camouflage and Chick Defense

When disturbed, the chick tucked itself into the nooks and crannies of the seawall. Its mottled brown, white and black plumage provided camouflage while it nestled itself against pieces of marine debris (image 5). We also observed it hiding in grass adjacent to the seawall.

As long as we remained stationary at distance, one of the adults, typically the female, would eventually approach the chick while vocalising a series of soft twiks. The chick would then get up and follow the adult. We did observe brooding by the male as well, though less frequently.

While plovers are among the group of birds known for using the “broken-wing display” in response to disturbances (Gómez-Serrano & López-López, 2017), we did not observe this behaviour. We only observed them vocalising and attempting to lead us away from the chick whenever we ventured too close. Sometimes, an adult approached us while vocalising.

On one occasion when a flock of crows roosted nearby, the chick went into hiding while the adults kept watch from a distance. We observed an adult flying out to sea when dived on by individual crows although it returned to the site shortly after. However, when disturbed by humans, the adults did not fly off and always stayed within visible distance.

Fledged?

On Sunday 25 July 2021, we made our way to Marina East again. This time however, there was no twik greeting from the male Malaysian Plover. The female was nearby bathing and preening in one of the puddles atop the seawall. The pair of Malaysian Plovers had seemingly reverted to their typical non-vocalizing and more confiding selves, and the chick was nowhere to be found. The absence of the chick had been noted the day before, with adults reportedly being skittish (Francis Yap, pers. comms.).

The chick was independently discovered by Max Khoo a day before us on 26 June (pers. comms.), and would have been at least 28 days old, within the fledging window of 27-33 days after hatching (Wiersma et al., 2020). Unfortunately, we later found out that the plovers were preyed upon by a House Crow Corvus splendens, putting the journey of the young bird to an end.

Nest Habitat and Conservation

Malaysian Plovers nest in coastal locations that typically include an intertidal mudflat for foraging, a sandy beach for nesting, and a shrubby vegetated area that can provide cover for chicks during disturbances (Yasué & Dearden, 2008). Natural habitats suitable for the nesting of the Malaysian Plover are declining locally due to developments. However, many local nesting records have been on reclaimed land and coastal defense structures – they have previously been documented laying their eggs on the seawall (image 6; Nicholas Lim, pers. comms.).

The diet of the Malaysian Plover is poorly known (Wiersma et al., 2020) but we have observed them foraging on algal cover on the seawall where they appear to feed on invertebrates, or perhaps even microorganisms. Interestingly, they are rarely observed feeding on the adjoining mudflat where other waders have been observed.

Across five weekends of observations, this was the only family of Malaysian Plovers sighted along the entire stretch of the Marina East seawall. During the migratory season, presumably a non-breeding period, there would typically be more Malaysian Plovers scattered along the seawall, including multiple male and female birds. Their highly territorial behaviour (Yasué & Dearden, 2008) likely makes it difficult for multiple pairs to share the territory when nesting.

Our observations suggest that the plovers might be adaptable to nesting on artificial structures, provided that areas necessary for food, egg-laying and cover are present. Locally, breeding has been recorded in March-April (Lim, 2009) and July-September (BESG, 2006; Goh, 2016), as well as in June this year (Raghav Narayanswamy, pers. comms.).

The presence of these pockets of breeding habitat are crucial to the continued presence of the Malaysian Plover in Singapore. Protection and management of such areas from human intrusion during the breeding season where the birds are most sensitive to disturbances can be considered.

Acknowledgements

Warm thanks to Francis, Max and Raghav for insights about their breeding, to Nicholas for sharing his photo and to the SBP team (Dillen, Movin, Sandra) for comments.

References

BESG. (2006). Malaysian Plover 2: Nesting. Bird Ecology Study Group. Retrieved 26 July 2021, from https://besgroup.org/2006/07/25/malaysian-plover-2-nesting/

Goh, C.T. (2016). Out of Season Breeding of the Malaysian Plovers in Singapore. Nature Society (Singapore) Singapore Bird Group. Retrieved 26 July 2021, from https://singaporebirdgroup.wordpress.com/2017/10/24/out-of-season-breeding-of-the-malaysian-plovers-in-singapore/

Gómez-Serrano, M.A., & López-López, P. (2017). Deceiving predators: linking distraction behavior with nest survival in a ground-nesting bird. Behavioral Ecology, 28(1), 260–269.
Link: https://academic.oup.com/beheco/article/28/1/260/2453523

BirdLife International. (2021). Species factsheet: Charadrius peronii. Retrieved 26 July 2021, from http://datazone.birdlife.org/species/factsheet/22693836

Lim, K.S. (2009). The Avifauna of Singapore. Nature Society (Singapore). Singapore.

Wiersma, P., Kirwan, G. M., & Boesman, P. F. D. (2020). Malaysian Plover (Charadrius peronii), version 1.0. In J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana (Eds.), Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.malplo1.01

Yasué, M. & Dearden, P. (2008). Parental sex roles of Malaysian Plovers during territory acquisition, incubation and chick-rearing. Journal of Ethology, 26(1), 99-112.Link: https://www.researchgate.net/profile/Philip-Dearden/publication/225332000_Parental_sex_roles_of_Malaysian_Plovers_during_territory_acquisition_incubation_and_chick-rearing/links/00b7d528dc22588a11000000/Parental-sex-roles-of-Malaysian-Plovers-during-territory-acquisition-incubation-and-chick-rearing.pdf

Gallery

 

Rufous Barn Swallows in Singapore?

TLDR;

  1. There are several records of Barn Swallows with rufous underparts in Singapore
  2. Relationships between the different Barn Swallow subspecies are still being explored – we are uncertain of which subspecies the rufous birds seen in Singapore belong to
  3. In the meantime, please share your sightings if you come across any of these rarer migrants!

Migratory birds are slowly streaming into Singapore as the Northern Hemisphere winter sets in. One of the commonest species that share the local aerospace with the resident swiftlets and Pacific Swallows Hirundo tahitica is the Barn Swallow H. rustica. The Barn Swallows are easily identifiable from their distinct clean white underparts but did you know that rufous Barn Swallows have been seen in Singapore before?

There have so far been at least three documented records of Barn Swallows with rufous underparts in Singapore, one at Punggol Barat on 3 April 2016, one at Neo Tiew on 21 December 2019 and another at Neo Tiew on 20 January 2020 (though possibly the same individual spotted a month earlier).

The usual Barn Swallows that visit Singapore during the wintering months are of the subspecies gutturalis (Chasen, 1923; Gibson-Hill, 1950) with clean white underparts along with a distinct black breast band (Figure 1). It is currently still unclear which subspecies these rufous Barn Swallows belong to, but what the local community can do in the meantime is to make sure that these records are properly documented while researchers continue to study their relationships!

Figure 1. Barn Swallow, subspecies gutturalis (taken by Keita Sin).

This article will become slightly technical from here onwards, but for those who have an interest in the biology of birds, read on!

Barn Swallow subspecies taxonomy is tricky; different authors have differing opinions on which subspecies are valid and the boundaries of their breeding ranges (Figure 2, Table 1). With regards to the subspecies that occur in Southeast Asia (and consequently Singapore), the International Ornithological Committee (IOC) recognises four subspecies, namely gutturalis, tytleri, mandschurica and saturata, while Birds of the World (BOTW) recognises gutturalis, tytleri and mandschurica too, but treats saturata as part of gutturalis instead. On the other hand, Dor et al. (2010) who has worked on Barn Swallow phylogeny lists two relevant subspecies, gutturalis and tytleri.

Figure 2. Range map of the different Barn Swallow subspecies.
Note. Reprinted from The Barn Swallow (p 21), by A. Turner, 2006, A&C Black Publishers Ltd. Copyright 2006 by Angela Turner.
Table 1. A summary of the differing treatments of the Barn Swallow subspecies according to authors.

Of the supposed four subspecies that might occur in Singapore, only one is described to have creamy white underparts (gutturalis), with the other three (tytleri, mandschurica and saturata) have some degree of rufous on the underparts (Table 2).

Table 2. Morphometrics and plumage description of relevant Barn Swallow subspecies.
Note. Adapted from The Barn Swallow (p 20), by A. Turner, 2006, A&C Black Publishers Ltd. Copyright 2006 by Angela Turner.

However, on top of the difficulty in distinguishing underpart colours (what is the difference between ochre, rufous and chestnut?), plumage can also vary with individuals and wear (Dickinson and Dekker, 2001). More significantly, there is likely to be interbreeding between different subspecies in intergrade zones within their breeding range (Dickinson and Dekker, 2001; Nazarenko, 2016; Turner, 2006). For instance, there are some interesting swallows that are within range of tytleri and/or where tytleri overlaps with other populations (such as gutturalis) that are not entirely white or rufous, and some examples are listed here: a) western Mongolia, mostly white underparts with rufous tinge; b) central Mongolia, underparts with faint rufous tinge; c) central Mongolia, pale rufous underparts d) northern Mongolia, white underparts with rufous vent. Compare these with birds found further north (that are presumably tytleri based on range) such as this and this that are clearly much more rufous in colour.

As the ornithological community continues to explore the answers to the relationships of the various Asian populations of Barn Swallows in their breeding ranges, the verdict on the “rufous” individuals in Singapore is still open to interpretation. However this doesn’t change the fact that they are quite rare locally, so please do share your sightings if you manage to spot or photograph any!

Disclaimer: The authors of this short article (Dillen and Keita) have not been involved in any of the Barn Swallow studies. We dove into this topic confused and emerged out of it even more confused – please let us know if there are any errors!

References:

Chasen, F. N. (1923). An introduction to the birds of Singapore island. Singapore Naturalist, 2, 87-111.

Dickinson, E. C., & Dekker, R. W. R. J. (2001). Systematic notes on Asian birds. 13. Preliminary review of the Hirundinidae. Zoologische Verhandelingen, 25, 127-144.

Dor, R., Safran, R. J., Sheldon, F. H., Winkler, D. W., & Lovette, I. J. (2010). Phylogeny of the genus Hirundo and the Barn Swallow subspecies complex. Molecular Phylogenetics and Evolution, 56, 409-418.

Gibson-Hill, C.A. (1950). A checklist of the birds of Singapore island. Bulletin of the Raffles Museum, 21, 132-183.

Nazarenko A.A., Pavlenko M.V., Kryukov A.P. (2016). Introgressija genov populjacii Hirundo rustica tytleri v populjaciju H. r. gutturalis na jugo-zapade Ussuriĭskogo kraja (na primere Vladivostoka): otgoloski bylyh i tekushhih istoriko-biogeograficheskih sobytiĭ [Introgression of the genes of the Hirundo rustica tytleri population in the H. r. gutturalis population in the south-west of the Ussuri region (upon the example of Vladivostok): echoes of past and current historical-biogeographical events]. Russkiĭ ornitologicheskiĭ zhurnal25, 523-536.

Turner, A. (2006). The barn swallow. T&AD Poyser.

Local extinctions of Singapore birds

There is an interesting paper recently published in the prestigious journal Conservation Biology by members of two National University of Singapore (NUS) labs titled “A robust non-parametric method for quantifying undetected extinctions” that came to our attention.

In it, they presented a novel method of estimating undetected extinction, i.e. the type of extinction events that may have taken place without humans taking note of them. They applied this new method to all 195 breeding bird species ever recorded in Singapore over the last 200 years. Of this number, 58 (~30%) are known to have gone extinct. They project probably another ~10 species have gone extinct without ever being discovered, thereby providing a more realistic extinction rate at ~33%.

The extinction of one-third of our resident bird species over the years represent a significant loss of our biodiversity. The authors also project based on the data from Singapore, an additional 14-16% loss of bird species in the region by the year 2100 with current deforestation rate. Some of our favorite birds are already extinct in Singapore. More will join their ranks without further conservation efforts, and it won’t be long before they are gone for good in the region as well.

One of the interesting side product of this new study is a new, extensively vetted list of all breeding birds ever recorded in Singapore based on thorough literature reviews going back to the 1800s. Reproduced with permission at the bottom of this post is a table containing the bird list of current and extinct species. This data represent a best effort by the authors at the time of publication. This website will use it as a starting point to update its own list in the future.

Photos of some of the birds that have gone extinct in Singapore:

Reference:
Chisholm R.A., Giam X., Sadanandan K.R., Fung T. & Rheindt F.E. (2016). A robust non-parametric method for quantifying undetected extinctions. Conservation Biology.

 

Table A1. Resident native birds of Singapore recorded since 1819. This list excludes species that were introduced by humans or for which evidence for breeding activity is too sparse. Some species for which breeding evidence is doubtful are included in the table but were excluded from the analysis described in the paper.

Common Name Name First record Last record
Blue-breasted Quail Coturnix chinensis chinensis 1819 2014
Red Junglefowl Gallus gallus spadiceus 1985 2014
Lesser Whistling-duck Dendrocygna javanica 1977 2014
Barred Buttonquail Turnix suscitator atrogularis 1819 2014
Sunda Pygmy Woodpecker Dendrocopos moluccensis moluccensis 1819 2014
Rufous Woodpecker Celeus brachyurus squamigularis 1819 2014
White-bellied Woodpecker Dryocopus javensis javensis 1819 2001
Banded Woodpecker Picus miniaceus malaccensis 1819 2014
Crimson-winged Woodpecker Picus puniceus continentis 1819 1949
Checker-throated Woodpecker Picus mentalis humii 1819 1949
Laced Woodpecker Picus vittatus vittatus 1819 2014
Olive-backed Woodpecker Dinopium rafflesii rafflesii 1819 1949
Common Flameback Dinopium javanese javanese 1819 2014
Greater Flameback Chrysocolaptes lucidus chersoneus 1819 1908
Orange-backed Woodpecker Reinwardtipicus validus xanthopygius 1819 1920
Buff-rumped Woodpecker Meiglyptes tristis grammithora 1819 1949
Buff-necked Woodpecker Meiglyptes tukki tukki 1819 1949
Great Slaty Woodpecker Mulleripicus pulverulentus 1819 1949
Grey-and-Buff Woodpecker Hemicircus concretus sordidus 1819 1949
Lineated Barbet Megalaima lineata hodgsoni 1996 2014
Red-crowned Barbet Megalaima rafflesii malayensis 1819 2014
Blue-eared Barbet Magalaima australis duvaucelii 1819 1949
Coppersmith Barbet Magalaima haemacephala indica 1957 2014
Brown Barbet Calorhamphus fuliginosus 1819 1949
Oriental Pied Hornbill Anthracoceros albirostris convexus 1819 2014
Red-naped Trogon Harpactes kasumba kasumba 1819 1921
Diard’s Trogon Harpactes diardii sumatranus 1819 1921
Dollarbird Eurystomus orientalis orientalis 1819 2014
Blue-eared Kingfisher Alcedo meninting verreauxi 1819 2014
Stork-billed Kingfisher Halcyon capensis malaccensis 1819 2014
White-throated Kingfisher Halcyon smyrnensis fusca 1819 2014
Collared Kingfisher Todiramphus chloris humii 1819 2014
Rufous-backed Kingfisher Ceyx erithacus rufidorsa 1819 1949
Ruddy Kingfisher Halcyon coromanda minor 1819 1986
Banded Kingfisher Lacedo pulchella 1819 1949
Rufous-collared Kingfisher Actenoides concretus concretus 1819 1938
Blue-throated Bee-eater Merops viridis viridis 1819 2014
Banded Bay Cuckoo Cacomantis sonneratii malayanus 1819 2014
Plaintive Cuckoo Cacomantis merulinus threnodes 1819 2014
Rusty-breasted Cuckoo Cacomantis sepulcralis sepulcralis 1819 2014
Little Bronze Cuckoo Chrysococcyx minutillus malayanus 1819 2014
Violet Cuckoo Chrysococcyx xanthorhynchus xanthorhynchus 1819 2014
Drongo Cuckoo Surniculus lugubris barussarum 1819 2014
Asian Koel Eudynamys scolopacea malayana 1819 2014
Rhinortha Rhinortha chlorophaea 1819 1895
Black-bellied Malkoha Phaenicophaeus diardi diardi 1819 1949
Chestnut-bellied Malkoha Phaenicophaeus sumatranus sumatranus 1819 2014
Greater Coucal Centropus sinensis bubutus 1819 2014
Lesser Coucal Centropus bengalensis javanensis 1819 2014
Blue-rumped Parrot Psittinus cyanurus cyanurus 1819 2014
Blue-crowned Hanging Parrot Loriculus galgulus galgulus 1819 2014
Long-tailed Parakeet Psittacula longicauda longicauda 1819 2014
Glossy Swiftlet Collocalia esculenta cyanoptila 1819 2014
Black-nest Swiftlet Collocalia maxima maxima 1819 2014
Edible-nest Swiftlet Collocalia fuciphaga amechana 1819 2014
Asian Palm Swift Cypsiurus balasiensis infumatus 1819 2014
House Swift Apus affinis subfurcatus 1819 2014
Silver-rumped Needletail Rhaphidura leucopygialis 1819 1949
Grey-rumped Treeswift Hemiprocne longipennis harterti 1881 2014
Whiskered Treeswift Hemiprocne comata 1819 1969
Barn Owl Tyto alba javanica 1970 2014
Collared Scops Owl Otus lempiji lempiji 1819 2014
Barred Eagle Owl Bubo sumatranus sumatranus 1819 1925
Buffy Fish Owl Ketupa ketupa ketupa 1819 2014
Spotted Wood Owl Strix seloputo seloputo 1985 2014
Brown Hawk Owl Ninox scutulata scutulata 1819 2014
Malaysian Eared Nightjar Eurostopodus temminckii 1819 1989
Large-tailed Nightjar Caprimulgus macrurus bimaculatus 1819 2014
Savanna Nighjar Caprimulgus affinis affinis 1988 2014
Spotted Dove Streptopelia chinensis tigrina 1819 2014
Emerald Dove Chalcophaps indica indica 1819 2014
Peaceful Dove Geopelia striata striata 1819 2014
Cinnamon-headed Green Pigeon Treron fulvicollis fulvicollis 1819 1927
Little Green Pigeon Treron olax olax 1819 2014
Pink-necked Green Pigeon Treron vernans griseicapilla 1819 2014
Thick-billed Green Pigeon Treron curvirostra curvirostra 1819 2014
Pied Imperial Pigeon Ducula bicolor bicolor 2004 2014
Green Imperial Pigeon Ducula aenea polia 1819 1970
Red-legged Crake Rallina fasciata 1819 2014
Slaty-breasted Rail Gallirallus striatus gularis 1819 2014
White-breasted Waterhen Amaurornis phoenicurus javanicus, chinensis, phoenicurus 1819 2014
Ruddy-breasted Crake Porzana fusca fusca 1819 2014
White-browed Crake Porzana cinerea 1819 2014
Purple Swamphen Porphyrio porphyrio viridis 1986 2014
Common Moorhen Gallinula chloropus orientalis 1973 2014
Greater Painted-Snipe Rostratula benghalensis benghalensis 1819 2014
Black-winged Stilt Himantopus himantopus himantopus 1992 1994
Malaysian Plover Charadrius peronii 1988 2014
Red-wattled Lapwing Vanellus indicus atronuchalis 1993 2014
Black-naped Tern Sterna sumatrana sumatrana 1819 2014
Little Tern Sterna albifrons sinensis 1987 2014
Black-winged Kite Elanus caeruleus vociferus 1986 2014
Brahminy Kite Haliastur indus intermedius 1819 2014
White-bellied Fish Eagle Haliaeetus leucogaster 1819 2014
Grey-headed Fish Eagle Ichthyophaga ichthyaetus 1950 2014
Crested Serpent Eagle Spilornis cheela bassus 1819 2014
Crested Goshawk Accipiter trivirgatus indicus 1987 2014
Changeable Hawk Eagle Spizaetus cirrhatus limnaeetus 1819 2014
Black-thighed Falconet Microhierax fringillarius 1819 1986
Little Grebe Tachybaptus ruficollis poggei 1994 2014
Pacific Reef Egret Egretta sacra sacra 1819 2014
Great-billed Heron Ardea sumatrana sumatrana 1819 2014
Grey Heron Ardea cinerea jouyi 1983 2014
Purple Heron Ardea purpurea manilensis 1940 2014
Striated Heron Butorides striatus javanicus 1819 2014
Black-crowned Night Heron Nycticorax nycticorax nycticorax 1983 2014
Yellow Bittern Ixobrychus sinensis 1986 2014
Cinnamon Bittern Ixobrychus cinnamomeus 1819 2014
Lesser Adjutant Leptoptilos javanicus 1882 1882
Mangrove Pitta Pitta megarhyncha 1819 2014
Garnet Pitta Pitta granatina coccinea 1819 1949
Dusky Broadbill Corydon sumatranus sumatranus 1819 1871
Black-and-red Broadbill Cymbirhynchus macrorhynchos malaccensis 1819 1949
Banded Broadbill Eurylaimus javanicus pallidus 1819 1927
Black-and-yellow Broadbill Eurylaimus ochromalus ochromalus 1819 1871
Green Broadbill Calyptomena viridis viridis 1819 1941
Golden-bellied Gerygone Gerygone sulphurea sulphurea 1819 2014
Asian Fairy Bluebird Irena puella malayensis 1819 2014
Greater Green Leafbird Chloropsis sonnerati zosterops 1819 2014
Lesser Green Leafbird Chloropsis cyanopogon cyanopogon 1819 2014
Blue-winged Leafbird Chloropsis cochinchinensis icterocephala 1819 2014
Long-tailed Shrike Lanius schach bentet 1969 2014
Mangrove Whistler Pachycephala grisola vandepolli 1819 2014
Large-billed Crow Corvus macrorhynchos macrorhynchos 1819 2014
Dark-throated Oriole Oriolus xanthonotus xanthonotus 1819 1941
Black-naped Oriole Oriolus chinensis maculatus 1936 2014
Bar-bellied Cuckooshrike Coracina striata sumatrensis 1819 1969
Lesser Cuckooshrike Coracina fimbriata culminata 1819 1969
Pied Triller Lalage nigra nigra 1819 2014
Fiery Minivet Pericrocotus igneus igneus 1819 1969
Scarlet Minivet Pericrocotus flammeus xanthogaster 1819 2014
Pied Fantail Rhipidura javanica longicauda 1819 2014
Bronzed Drongo Dicrurus aeneus malayensis 1819 1949
Greater Racket-tailed Drongo Dicrurus paradiseus platurus 1819 2014
Black-naped Monarch Hypothymis azurea prophata 1819 2014
Asian Paradise-flycatcher Terpsiphone paradisi affinis 1819 1990
Common Iora Aegithina tiphia singapurensis 1819 2014
Green Iora Aegithina viridissima viridissima 1819 1949
Rufous-winged Philentoma Philentoma pyrhoptera 1819 1949
Maroon-breasted Philentoma Philentoma velatum caesia 1819 1879
Large Woodshrike Tephrodornis gularis fretensis 1819 1949
Mangrove Blue Flycatcher Cyornis rufigastra rufigastra 1819 2000
Oriental Magpie Robin Copsychus saularis musicus 1819 2014
White-rumped Shama Copsychus malabaricus mallopercna 1819 2014
Asian Glossy Starling Aplonis panayensis strigatus 1819 2014
Common Myna Acridotheres tristis tristis 1935 2014
Hill Myna Gracula religiosa javana 1819 2014
Pacific Swallow Hirundo tahitica abbotti 1819 2014
Straw-headed Bulbul Pycnonotus zeylanicus 1819 2014
Black-headed Bulbul Pycnonotus atriceps atriceps 1819 2014
Grey-bellied Bulbul Pycnonotus cyaniventris cyaniventris 1819 1949
Yellow-vented Bulbul Pycnonotus goiavier personatus 1819 2014
Olive-winged Bulbul Pycnonotus plumosus plumosus 1819 2014
Cream-vented Bulbul Pycnonotus simplex simplex 1819 2014
Yellow-bellied Bulbul Alophoxius phaeocephalus phaeocephalus 1819 1924
Buff-vented Bulbul Iole olivacea olivacea 1819 1949
Spectacled Bulbul Pycnonotus erythropthalmos erythropthalmos 1819 1949
Red-eyed Bulbul Pycnonotus brunneus brunneus 1819 2014
Zitting Cisticola Cisticola juncidis malaya 1819 2014
Yellow-bellied Prinia Prinia flaviventris rafflesi 1819 2014
Oriental White-eye Zosterops palpebrosus 1819 2014
Common Tailorbird Orthotomus sutorius maculicollis 1819 2014
Dark-necked Tailorbird Orthotomus atrogularis atrogularis 1819 2014
Rufous-tailed Tailorbird Orthotomus sericeus hesperius 1819 2014
Ashy Tailorbird Orthotomus ruficeps ruficeps 1819 2014
White-chested Babbler Trichastoma rostratum rostratum 1819 2014
Abbott’s Babbler Malacocincla abbotti olivacea 1819 2014
Short-tailed Babbler Malacocincla malaccensis malaccensis 1819 2014
Black-capped Babbler Pellorneum capistratum nigrocapitatum 1819 1899
Moustached Babbler Malacopteron magnirostre magnirostre 1819 1986
Chestnut-winged Babbler Stachyris erythroptera erythroptera 1819 2014
Striped Tit Babbler Macronous gularis gularis 1819 2014
Yellow-breasted Flowerpecker Prionochilus maculatus maculatus 1819 1969
Yellow-vented Flowerpecker Dicaeum chrysorrheum chrysorrheum 1819 2014
Orange-bellied Flowerpecker Dicaeum trigonostigma trigonsostigmum 1819 2014
Plain Flowerpecker Dicaeum concolor borneanum 1819 1931
Scarlet-backed Flowerpecker Dicaeum cruentatum ignitum 1819 2014
Plain Sunbird Anthreptes simplex simplex 1819 1874
Brown-throated Sunbird Anthreptes malacensis malacensis 1819 2014
Purple-naped Sunbird Hypogramma hypogrammicum macularia 1819 1969
Purple-throated Sunbird Nectarinia sperata brasiliana 1819 2014
Copper-throated Sunbird Nectarinia calcostetha calcostetha 1819 2014
Olive-backed Sunbird Nectarinia jugularis microleuca 1819 2014
Crimson Sunbird Aethopyga siparaja siparaja 1819 2014
Little Spiderhunter Arachnothera longirostra longirostra 1819 2014
Thick-billed Spiderhunter Arachnothera crassirostris 1819 1920
Yellow-eared Spiderhunter Arachnothera chrysogenys chrysogenys 1819 2014
Grey-breasted Spiderhunter Arachnothera affinis modesta 1819 1949
Eurasian Tree Sparrow Passer montanus malaccensis 1819 2014
Paddyfield Pipit Anthus rufulus sinensis 1819 2014
Baya Weaver Ploceus philippinus infortunatus 1819 2014
White-rumped Munia Lonchura striata subsquamicollis 1883 2014
Scaly-breasted Munia Lonchura punctulata fretensis 1819 2014
Black-headed Munia Lonchura malacca sinensis 1819 2014
White-headed Munia Lonchura maja maja 1819 2014