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101BirdingASIA 37 (2022): 101–108
The COVID-19 pandemic has taken a heavy toll on the
global birdwatching industry, as well as the physical
and mental well-being of individuals. As a result of
being confined in Singapore, many in the nat ion have
adopted birdwatching and nature photography as a
pastime. Thi s massive growt h in the local bi rdwatching
community meant that there was unprecedented
coverage of sites across the nation and this surge in
observer effort contributed to many unexpected
discoveries. There are now as many as 3,000 active
observers in Singapore, whereas three years ago that
number would have been less than 500. The calendar
year of 2021 alone brought about a remarkable 12
national first records for Singapore, with some being
the first records for the Sundaic region.
Here we highlight significant species that were
discovered from May 2020 to January 2022. For other
sightings from the 2019/2020 season, we direct
readers to Sin et al. (2020). Taxonomy and
nomenclature follow ‘IOC’ ta xonomy (Gill et al. 2022).
The initials of first sightings and the full names of
contributors to records are as follows: Alex Ka ng (AK),
Art Toh (AT), Boo (B), Cecilia Lee (CL), Choo Shiu
Ling (CSL), Dave Bakewell (DB), Daniel Loh (DL),
Dillen Ng (DN), Derrick Wong (DW), Desmond Yap
(DY), Eunice Kong (EK), Frankie Cheong (FC), Frank
Rheindt (FR), Francis Yap (FY), George Presanis (GP),
Ian Cash (IC), James Eaton (JE), Justin Jing Liang
(JJL), Julia Presanis (JP), Jan Tan (JT), Jackie Yeo
(JY), Kenneth Chow (KC), Kian Guan Tay (KGT), Koh
Tian Teck (KTT), Khaleb Yordan (KY), Lee Chien Nien
(LCN), Lim Hong Yao (LHY), Lee Lay Na (LLN), Lim
Yu Jun (LYJ), Mike Hooper (MH), Martin Kennewell
(MK), May Swales (MS), Oliver Tan (OT), Pher Thuan
Chong (PTC), Siok Khim (SK), S. M. A. Rashid
(SMAR), Sreekar Rachakonda (SR), Siti Soedarsono
(SS), Tan Hui Zhen (THZ), Theen Peng Voon (TPV),
Thomas Soo (TS), Vincent Chin (VC), Vincent Lao
(VLa), Vincent Lee (VLe), Vinod Saranathan (VS),
Vincent Yip (VY), William Khaw (WK), Yong Chee
Keita Sin (YCKS), Yong Ding Li (YDL), Yip Jen Wei
(YJW), Yeo Suay Hwee (YSH), Zahidi Hamid (ZH).
Summary of observations from Singapore
Migrants and vagrants
Second records of Gadwall Mareca strepera—a flock
of five at Sungei Buloh Wetland Reserve on 4
December 2020 (DL), the first for 31 years—and
Tufted Duck Aythya fuligula—at Marsiling Park on
12 December 2020 (DW), the previous record
coming in 1999.
First and second records of Common Swift Apus
apus pekinensis were found at Jelutong Tower on
9 October 2020 (FY, MK, RW) and Henderson
Waves on 27 October 2020 (YCKS; Sin et al. 2021)
respectively.
Third and fourth records of Asian Emerald
Cuckoo Chrysococcyx maculatus on Pulau Ubin
from 5 to 8 March 2021 (MS) and Jurong Lake
Gardens from 27 December 2021 to at least 30
January 2022 (TPV) respectively. Both sightings
were accompanied by a feeding frenzy of other
cuckoo species, including Square-tailed Drongo-
cuckoo Surniculus lugubris, Little Bronze Cuckoo
C. minutillus and Large Hawk-cuckoo Hierococcyx
sparverioides among others.
First record of Ashy-headed Green Pigeon
Treron phayrei—typically a resident of the
Indochinese region—was found among a flock of
Thick-billed Green Pigeons T. curvirostris from 9
to 11 October 2021 (YJW) in the Central Catchment
Nature Reserve (Plate 1).
NEW RECORDS
Beyond the pandemic: gems from Singapore
in 2020−2021
YONG CHEE KEITA SIN, RAGHAV NARAYANSWAMY, DILLEN NG, SANDRA J. M. CHIA, ELIZE Y. X. NG
& MARTIN KENNEWELL
Plate 1. Ashy-headed Green Pigeon Treron phayrei, Central
Catchment Nature Reserve, 10 October 2021.
YIP JEN W EI
102 Beyond the pandemic: gems from Singapore in 2020−2021
The country’s fifth record of Red Knot Calidris
canutus was found at Seletar Dam on 6 September
2021 (VY), the first for 24 years, where it stayed
for only one evening. Fifth record of Caspian Tern
Hydroprogne caspia at Mandai Mudflats on 17
November 2020 (YSH).
Second record of Wedge-tailed Shearwater
Ardenna pacifica, found grounded at Bishan Ang
Mo Kio Park on 23 June 2021 (WK), succumbed to
exhaustion despite being sent to a rehabilitation
centre. Coincidentally, Singapore's first record of
this species was also of a grounded bird found in
Woodlands almost exactly 23 years earlier on 22
June 1998 (SMAR).
A remarkable record (unsurprisingly
Singapore’s first) of Cinereous Vulture Aegypius
monachus, together with a flock of five Himalayan
Vultures Gyps himalayensis, at Singapore Botanic
Gardens from 29 to 30 December 2021 (CL, JJL,
MK). The bird was grounded on 30 December 2021
and sent to a rehabilitation centre for care before
being released on 10 January 2022 (Plate 2). The
bird was grounded again at a nearby golf course
the next day and was not seen thereafter.
First record of Long-eared Owl Asio otus at
Marina East Drive on 20 November 2021 (CSL).
This record was deemed by the Singapore Bird
Records Committee (SBRC) to be ship-assisted
based on the location—it was found along a coast
with heavy ship traffic and there have been recent
records of this species on ships in the South China
Sea (Singapore Birds Project [SBP] 2022). Fourth
record of Amur Falcon Falco amurensis at Lorong
Halus from 26 November to 14 December 2021 (LYJ;
Plate 3). First record of Eurasian Hobby F. su bbuteo
over Henderson Waves on 23 October 2020 (ZH).
Second record of Fairy Pitta Pitta nympha at
Hindhede Nature Park from 30 October to 4
November 2021 (VLa).
First and second records of the recently split
Siberian House Martin Delichon lagopodum at Neo
Tiew Harvest Lane on 3 January 2021 (MH) and
Marina East Drive on 28 December 2021 (OT)
respectively, with the first record only identified
post-hoc by FR from online photographs.
Fourth record of Dusky Warbler Phylloscopus
fuscatus at Marina East Drive from 27 December
2021 to at least 30 January 2022 (LCN). First record
of Pale-legged Leaf Warbler P. tenellipes at
Macritchie Reservoir from 12 November to 3
December 2021 (SR, YDL). This individual was
distinguished from the morphologically similar
Sakhalin Leaf Warbler P. borealoides by its
diagnostic call (Yap et al. 2014, Round et al. 2016,
Hungnon et al. 2017). A Sakhalin Leaf Warbler was
also present in the vicinity of the Pale-legged Leaf
Plate 2. Cinereous Vulture Aegypius monachus being released at Lim Chu Kang after being rehabilitated. 4 January 2022.
VINCENT NG
103BirdingASIA 37 (2022)
Warbler and vocalisations of both birds were
within earshot at some sites, allowing for recordings
of both calls. Since the first confirmed Sakhalin
Leaf Warbler in 2013, there have been at least 15
verifiable records of this species in Singapore (Yap
et al. 2014, SBP 2022). At present, it seems that the
‘default’ species from the Sakhalin/Pale-legged
Leaf Warbler complex that winters in Singapore is
Sakhalin.
Second record of White-cheeked Starling
Spodiopsar cineraceus at Holland Plain from 24 to
25 April 2021 (GP, JP). First record of Common
Starling Sturnus vulgaris at Marina East Drive from
13 to 14 December 2021 (KTT; Plate 4).
First record of Spotted Flycatcher Muscicapa
striata from 15 to 29 October 2021 at Kent Ridge
Park (AK; Plate 5). First verifiable record of Grey-
streaked Flycatcher M. griseisticta at Sembawang
from 9 to 17 November 2021 (DY); a previous record
from Poyan on 21 April 1991 was rejected due to a
lack of conclusive evidence (SBP 2022). Fourth
record of Chinese Blue Flycatcher Cyorn i s
glaucicomans came from Jurong Lake Garden on
11 October 2020 (DN, YCKS). Third and fourth
records of Narcissus Flycatcher Ficedula
narcissina, a female at Dairy Farm Nature Park on
Plate 3. Amur Falcon Falco amu rensis at Lorong Halus. This
individual was seen by over 100 birdwatchers on the day af ter
it was discovered. 27 November 2021.
GOH CHE NG TENG
Plate 4. Singapore’s rst Common Starling Sturnus vulga ris at
Marina East Drive. 14 December 2021.
ADRIA N SILAS TAY
Plate 5. Spotted Flycatcher Muscicapa striata, Kent Ridge Park,
19 October 2021.
NICHOLAS LIMFRANCIS YAP
Plate 6. Black Redstart Phoenicurus ochruros, Pasir Panjang.
7 December 2021.
104
19 to 21 November 2020 (SK) and a male at
Singapore Botanic Gardens from 2 to 6 December
2020 (VLe) respectively. First record of Black
Redstart Phoenicurus ochruros along a canal in
Pasir Panjang from 28 November 2021 (IC) to at
least 2 February 2022 (Plate 6).
First record of Tree Pipit Anthus tr ivialis from
19 October to 31 October 2021 at Ulu Pandan Park
Connector (SS). While sound-recordings of the bird
could not be obtained, numerous photographs were
taken to safely distinguish it from the similar
looking (and much less expected) Meadow Pipit
A. pratensis.
Visitors of local signicance from surrounding
regions
Second rec ord of Pied Stilt Himantopus leu cocephalus,
photographed at Pulau Tekong on 28 June 2021
among a flock of stilts (FC). This species was first
recorded—and successfully bred—at the same
location in July 2019 (Lim & Tan 2019), but no such
breeding attempts were recorded this time.
Singapore’s first Javan Plover Charadrius
javanicus was at Pulau Tekong from 20 June to 2
August 2021 (FC). Three birds photographed on
reclaimed land off Pulau Tekong were initially
assumed to be Kentish Plovers C. alexandrinus, but
from images subsequently posted online were
identified as Javan Plovers by JE, DB and KY (Plates
7 & 8). Additional photographs revealed that the
trio comprised an adult male and female, along
with a recently-fledged juvenile. The Javan Plover
was thought to be endemic to the island of Java
but has since been found along the coasts of
Sumatra and Sulawesi, suggesting an expansion
in range. Records now exist as far east as Timor-
Leste and north to the Minahasa peninsula,
Sulawesi, and it was also found breeding in
Lampung, Sumatra, in 2007 (Tebb et al. 2008, Iqbal
et al. 2011, Eaton et al. 2021). Likewise, the Pied
Stilt is known from the Indonesian Archipelago
and Australasia but has now made its way
northwards to Singapore, Malaysia, and Thailand.
Second record of Brown Fish Owl Ket upa
zeylonensis at Hindhede Nature Park from 17
February to 8 March 2021 (JY; Plate 9). Following
this sighting, it was revealed that this species, and
possibly t he same individual, was fi rst photographed
in 2019 at the same location, then thought to
be a Buffy Fish Owl K. ketupu (JT). This species is
not known to show long-distance movements and
there are few records from southern Malaysia
Plate 7. Javan Plover Charadrius javanicus, Pulau Tekong, 15
July 2021.
FRANK IE CHEONG
Plate 8. Recently-edge d Javan Plover, Pulau Tekong, 20 June
2021.
FRANK IE CHEONG
Plate 9. Brown Fish Owl Ketupa zeylonensis, Hindhede Nature
Park, 17 February 2021.
JACKIE Y EO
Beyond the pandemic: gems from Singapore in 2020−2021
105BirdingASIA 37 (2022)
(Wells 1999). The provenance of this bird remains
unclear (SBP 2022).
Three records of Black-thighed Falconet
Microhierax fringillarius represent the first sightings
for over 30 years, at Yishun on 12 February 2021
(LLN), Goldhill on 30 May 2021 (AT), and Jalan
Mashhor from 9 to 11 July 2021 (AT). The latter
two records are likely to be the same individual,
given the short distance between both locations.
Third record of Green Broadbill Calyptomena
viridis since its extirpation around 1941 (Wang &
Hails 2007), at Pulau Ubin from 6 April to 22 August
2021 (LHY, THZ; Plate 10). A record of a male
Scarlet Minivet Pericrocotus speciosus at Goldhill
on 25 February 2021 (TS), first confirmed record
since its likely extirpation nearly two decades ago.
First record of White-bellied Erpornis Erpornis
zantholeuca at Bukit Timah Nature Reserve from
16 to 17 June 2020 (RW). Despite being prevalent
in Peninsular Malaysia (Wells 2007, Puan et al.
2020), this species has surprisingly not been
recorded in Singapore before (Wang & Hails 2007).
Four records of Black-naped Monarch
Hypothymis azurea, at Pulau Ubin on 25 January
2021 (EK), Jurong Lake Gardens on 15 March 2021
(PTC, VC), Clementi Woods Park on 20 March 2021
(FR; possibly the same individual as the 15 March
record given their proximity), and at the Central
Catchment Nature Reserve from 12 to 13 October
2021 (KGT). This species was extirpated from
Singapore island around 1950 (Wells 2007), with
only a handful of records since. Intriguingly, a
population persists on Pulau Tekong, only 2 km
away from Singapore island (Wang & Hails 2007).
However, records on Singapore and adjacent
islands are equally rare (SBP 2022). Given that this
is a species tolerant of degraded habitat (Wells
2007), the overall scarcity of the Black-naped
Monarch on such a small spatial scale suggests
their poor over-water dispersal rates.
First record of Malayan Black Magpie
Platysmurus leucopterus at Hindhede Nature Park
on 9 June 2021 (VS, KC).
First verifiable record of Scarlet-breasted
Flowerpecker Prionochilus thoracicus was at Bukit
Pla te 10. Green Broadbill Calyptomena viridis, Pulau Ubin, 22
August 2021.
TAN HUI ZHEN
Figure 1. Mosaic of w intering range maps of all species found during the 2019/2020 and 2021/2022 migratory seasons with
<6 historic records in Singapore, with n referring to the total number of species included in each respec tive map. The number
of overlapping species is indicated by the intensit y of red in the legend. Species lists and shap e les were obtained from the
Singapore Bird Database and from the IUCN Red List respective ly. Maps were generated via ArcMap by removing the breeding,
resident and non-native ranges from the IUCN shape les. For 2019/2020, shape les of the Hair-crested Drongo Dicrurus
hottentottus were manuall y edited to align with the lates t taxonomy, and the ‘Resident ’ range was used. For 2021/2022, the ‘Resident ’
range was used for Ashy-headed Green Pige on Treron phayrei as it is typically a non-migratory sp ecies.
106 Beyond the pandemic: gems from Singapore in 2020−2021
Timah Nature Reserve on 29 November 2021 (B).
A previous claim from Pulau Ubin on 1 January
2015 could not be verified due to a lack of
descriptions (SBP 2022).
Discussion
Large-scale movements
Multiple unexpected species detected in the
2021/2022 season typically winter in the Middle
Eastern and/or Indian region (e.g. Black Redstart,
Spotted Flycatcher, Tree Pipit), contrasting greatly
with the 2019/2020 season where a large percentage
of vagrants to Singapore arrived from the
Indochinese region (Figure 1; Sin et al. 2020).
Weather patterns could have been one of the
factors affecting the appearance of vagrants in
Singapore. Within the last f ive years, the Indian Ocean
Dipole was in a positive phase i n the 2019/2020 season
and negative phase during the 2020/2021 and
2021/2022 season s (Saji et al. 1999, Japan Meteorologic al
Agency 2022). Such phases are associated with
changes in wind direction across the Indian Ocean
(Kripalani & Kumar 2004), which may potentially
have affected the migratory patterns of birds.
Various factors are also known to affect
vagrancy, such as population size, reproductive
success of the focal species, and climate (Pfeifer et
al. 2007, Nilsson & Sjöberg 2016, Ralph & Wolfe
2018, Zawadzki et al. 2019). While a wide array of
documentation on vagrancy is available from
Europe a nd America, such reports a re comparatively
scarce in Asia (Elkins 2008, Lees & Gilroy 2009,
Bozó et al. 2016, Ralph & Wolfe 2018).
Records of rare birds not only bring about joy
to the local community but are also data points
that greatly contribute to elucidating migratory
patterns and evolutionary changes (Lees & Gilroy
2021). Recent works have identified that the
Richard’s Pipit Anthus richardi, previously thought
to be a vagrant to south-western Europe, has
established new migratory routes due to
environmental changes over the past few decades
(Dufour et al. 2021).
Numerous studies from the past decade have
revealed different migratory routes and strategies
of Asian birds across various groups (Makalew et
al. 2015, Sander et al. 2017, Bozó et al. 2018, Heim
et al. 2018, Nourani et al. 2018, Heim et al. 2020,
Li et al. 2020, Yamaguchi et al. 2021). Uncovering
the cause of the recent high volume of vagrants
that arrived in Singapore is still difficult due to the
lack of other data points throughout the region. It
is hoped that the detailed documentation of such
vagrancy patterns will contribute to further
scientific discoveries as the wealth of data points
accumulate through citizen science platforms such
as iNaturalist and eBird.
Short distance movements
Unlike the vagrants documented in Singapore,
records of visitors from surrounding regions may
seem insignificant to those familiar with the
Sundaic avifauna. Indeed, many of the highlighted
species can be easily seen in forested areas in
neighbouring regions, some less than an hour’s
drive from the Singapore–Malaysia border (Wells
Figure 2. Number of unique records of Cinereous Bulbuls Hemixos cinereus and Streaked Bulbuls Ixos malaccensis in Singapore
from 2012 to 2022, overlaid with the number of records of locally signicant lowland Sundaic birds (species with fewer than 10
records in the past 10 years).
107BirdingASIA 37 (2022)
20 07, Pua n et al. 2020), and others on small islands
as close as 10 km from Singapore in the Riau
archipelago of Indonesia (Eaton et al. 2021). Many
of these species have been extirpated from
Singapore over the past few decades (Wang & Hails
2007, Chisholm et al. 2016). However, high observer
effort coupled with the lack of historical and
modern records for these lowland Sundaic birds
has placed Singapore in a suitable position to
accurately detect their localised mass movements.
Notably, the detection of Sundaic birds that are
sparsely recorded in Singapore seem to correspond
with irruptive events. The increased periodic
sightings of Cinereous Bulbuls Hemixos cinereus,
typically accompanied by Streaked Bulbuls Ixos
malaccensis, appear to coincide with observations
of other Sundaic species (Figure 2). These two
species are uncommon and rare visitors to
Singapore respectively, and in 2021 an influx was
observed with over 103 Cinereous Bulbuls and 6
Streaked Bulbuls detected in various locations. The
last time such a phenomenon was observed in
Singapore was during 2014/2015, when similarly
over 100 Cinereous Bulbuls were sighted, along
with Streaked Bulbul sightings scattered across the
country. In late 2014, several common lowland
Sundaic species that are generally absent from
Singapore, such as Green Broadbill, Thick-billed
Flowerpecker Dicaeum agile, Yellow-vented
Flowerpecker D. chrysorrheum and Yellow-eared
Spiderhunter Arachnothera chrysogenys, were also
seen, drawing parallels with the 2021 sightings
described above.
While altitudinal displacements of well-known
species in the region have been documented (e.g.
Rheindt 2004), such incidents of irruptive events
are not well covered. It seems that an exodus of
lowland species—presumably from Johor,
Malaysia—occasionally arrives in Singapore, and
these movements can be tracked by an increase in
the two bulbuls that serve as ‘indicator species’
(Figu re 2).
Underdetected migrants?
Species such as Common Swift and Siberian House
Martin are likely to be overlooked and closely
related species should be photographed for
confirmation when possible. The recent split of the
Siberian House Martin (Leader et al. 2021)
encouraged members of the local community to
pay attention to these fast-flying birds, which led
to the discovery of the first two national records.
So far, the majority of identifiable martins from
earlier in the season (September to mid-November)
in Singapore have been the ‘expected’ Asian House
Martin Delichon dasypus. While data points are
scarce at present, we speculate that December and
January may be a good period to look for the
Siberian House Martin (in Singapore and
neighbouring countries) based on current records.
Conclusion
While Singapore’s land area is not particularly
large, the country’s unique position at the end of
the peninsula in South-East Asia and high observer
density have allowed for robust detection of birds
passing through. Hundreds, if not thousands of
birdwatchers are paying attention to all corners of
the nation, from forests in the nature reserves to
drainage canals in residential areas. It is hoped
that continued documentation of sightings from
Singapore will contribute to an improved resolution
of vagrancy patterns in the region.
Acknowledgements
We thank the local birdwatching fraternity,
especially the discoverers of the significant records,
for finding and sharing their sightings with the
community. We are also grateful to James Eaton
for assistance with this manuscript.
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Yong Chee Keita Sin
Department of Biological Sciences
National University of Singapore
16 Science Drive 4
117558 Singapore
Email: dbssyck@nus.edu.sg
Yong Chee Keita Sin, Raghav Narayanswamy,
Dillen Ng, Sandra J. M. Chia,
Elize Y. X. Ng & Martin Kennewell
Singapore Birds Project
Email: sgbirdsproject@gmail.com
Elize Y. X. Ng
Discipline of Biological Science
School of Natural Sciences
University of Tasmania
Hobart, Tasmania
Australia
Beyond the pandemic: gems from Singapore in 2020−2021
