ArticlePDF Available

Biology, taxonomy and conservation status of the Short-tailed Green Magpie Cissa [t.] thalassina from Java

Authors:

Abstract and Figures

Summary The Short-tailed Green Magpie Cissa thalassina, a member of an Asian lineage of uniquely coloured corvids, is represented by two subspecies, thalassina and jefferyi, that occur on the islands of Java and Borneo, respectively. The distinct Javan nominate form is poorly described in the literature and next to nothing is published on its biology and occurrence in the wild. We here document the biology and distribution of this taxon based on hitherto unpublished historical data and on our own fieldwork. We also analyse vocal data of jefferyi, thalassina and two other Cissa species and show that jefferyi and thalassina are well-differentiated, and that thalassina is bioacoustically more similar to another Cissa species from the Asian mainland. We also demonstrate important and significant biometric differences between jefferyi and thalassina that may reflect divergent adaptations to the environment, as well as plumage differences that may serve signalling functions. Finally, the application of a novel species delimitation test to our data suggests that jefferyi and thalassina deserve to be classified as biological species because their phenotypic divergence exceeds that found in many sympatric species. The revised taxonomic status of Javan thalassina invites a reconsideration of its threat status. Based on its restricted range, extreme rarity and threats by bird trapping and habitat destruction, we consider the Javan Green Magpie as globally Critically Endangered.
Content may be subject to copyright.
Bird Conservation International, page 1 of 19. © BirdLife International, 2011
doi:10.1017/S0959270911000360
Biology, taxonomy and conservation
status of the Short-tailed Green Magpie
Cissa [t.] thalassina from Java
S. (BAS) VAN BALEN, JAMES A. EATON and FRANK E. RHEINDT
Summary
The Short-tailed Green Magpie Cissa thalassina, a member of an Asian lineage of uniquely
coloured corvids, is represented by two subspecies, thalassina and jefferyi, that occur on the
islands of Java and Borneo, respectively. The distinct Javan nominate form is poorly described in
the literature and next to nothing is published on its biology and occurrence in the wild. We here
document the biology and distribution of this taxon based on hitherto unpublished historical data
and on our own eldwork. We also analyse vocal data of jefferyi, thalassina and two other Cissa
species and show that jefferyi and thalassina are well-differentiated, and that thalassina
is bioacoustically more similar to another Cissa species from the Asian mainland. We also
demonstrate important and signicant biometric differences between jefferyi and thalassina that
may reect divergent adaptations to the environment, as well as plumage differences that may
serve signalling functions. Finally, the application of a novel species delimitation test to our data
suggests that jefferyi and thalassina deserve to be classied as biological species because their
phenotypic divergence exceeds that found in many sympatric species. The revised taxonomic
status of Javan thalassina invites a reconsideration of its threat status. Based on its restricted
range, extreme rarity and threats by bird trapping and habitat destruction, we consider the Javan
Green Magpie as globally Critically Endangered.
Introduction
The Asian genus Cissa Boie, 1826 is a complex of twelve taxa of green magpies. Although
sometimes lumped with the ve predominantly blue species of Urocissa into one genus
(dos Anjos 2009), they form a discrete lineage, members of which look uniform with a green
plumage, unique amongst corvids. Their present taxonomic relationships are still insufciently
studied, and in particular the taxonomic status of both races of Short-tailed Green Magpie Cissa
thalassina needs to be elucidated (Wolters 1977, Dickinson et al. 2004).
To date the following taxa have been described: (1) chinensis Himalayas and northern
Indochina, (2) minor Sumatra and Borneo, (3) robinsoni extreme south-west Thailand and
peninsular Malaysia, (4) klossi central Annam (Vietnam) and central Laos, (5) margaritae Mt
Lang Bian (central-southern Vietnam), (6) hypoleuca south-east Thailand, central and southern
Laos, southern Vietnam (southern Annam and Cochinchina), (7) chauleti central Annam
(Vietnam), (8) concolor eastern Tonkin and northern Annam (north Vietnam), (9) jini south-
central China, (10) katsumatae Hainan Island, (11) thalassina west and central Java,
(12) jefferyi northern Borneo.
Various arrangements have been described on geographical and morphological grounds. The
most speciose was by Delacour (1929) who recognised six species: C. chinensis (taxa 1
5),
C. hypoleuca (taxa 67), C. jefferyi, C. katsumatae, C. concolor (taxa 89) and C. thalassina.
Kuroda (1933) and Chasen (1935) lumped all forms into one species. Vaurie (in Peters 1962)
recognised two species: Green C. chinensis (taxa 15) and Short-tailed Magpie C. thalassina (taxa
612). This system was followed by Sibley and Monroe (1990), who, however, considered the
latter as having three distinct subspecies: Yellow-breasted, Bornean and Short-tailed Magpie.
Goodwin (1976, 1986) grouped the forms into three species: Common C. chinensis (taxa 15),
Indochinese C. hypoleuca (taxa 610) and Short-tailed C. thalassina (taxa 1112), and this is
followed by many subsequent standard works, such as Walters (1980) and Howard and Moore
(1980). These three species are considered a superspecies by dos Anjos (2009), an arrangement
that is obviously mistaken in view of the sympatry between Common Green Magpie and both
other species.
The (sub)specic distinctions are based on body size, tail length and shape, colour pattern of
tertials and tail, and yellow wash on body and crown (see Table 1). Both Short-tailed Magpie taxa
(thalassina and jefferyi) are mainly distinguished by their short tails. Not surprisingly,
vocalisation has never been used as a taxonomic character as this aspect of the genus is complex,
and rather intangible as in most corvids, due to intergradation, individual variation, frequent
vocal mimicry, etc. (dos Anjos 2009). Cissa thalassina was rst described by Temminck in 1826.
Although being lumped with the other green magpies, the race thalassina is described as a very
distinct form by Kuroda (1933). In this paper we use morphological characters as well as vocal
characters to examine the level of differentiation between jefferyi and thalassina. We also use
a novel phenotypic species delimitation test (Tobias et al. 2010) to evaluate if phenotypic
differences between jefferyi and thalassina are comparable to other pairs of sister taxa that are
ranked at the biological species level.
Very little is published on the natural history of the distinct Javan race of Short-tailed
Green Magpie (Madge and Burn 1994
, dos Anjos 2009), and its specic name thalassina (meaning
sea-green or bluish-green, the general colour of preserved skins or of birds kept in captivity)
given by its describer, C. J. Temminck in 1826, is symptomatic of the status of knowledge of
these birds in their natural environment, described as rugged and inaccessible (de Visard de
Bocarmé 1829).
This paper summarises all that is presently known about the biology and status of the Javan
Short-tailed Green Magpie. Once listed as near-threatened in Collar et al. (1994), Short-tailed
Green Magpie was not considered in BirdLife International (2001). New insight into its taxonomy
necessitates a reassessment of its global status.
Table 1. Measurements and plumage characteristics for three Cissa taxa (from Madge and Burn 1994).
thalassina/jefferyi hypoleuca chinensis
Tail length (mm) 97110 [114]157 171210
Body length (cm) 3133 3435 3739
Tail shape short, bluntly
graduated
intermediate,
central feathers hardly
project beyond next pair
strongly graduated
Tertials no obvious
pattern
Plain, broadly tipped &
fringed green, no spotting
tipped with black-
and-white spots
Underparts green strongly washed lemon-
yellow
pea or leaf green
Crown colour green green yellowish green (most races)
to bright golden yellow
Crown structure shorter feathers intermediate? elongated rear crown &
nape feathers
S. van Balen et al. 2
Material and methods
Data acquisition
We gathered sound recordings for both currently recognised subspecies of C. thalassina as well as
for a number of individuals each of C. chinensis and C. hypoleuca. Recordings of different
subspecies of C. hypoleuca and C. chinensis were each pooled for vocal analysis. We recorded
vocalisations in the eld in Indonesia, Cambodia and Vietnam and supplemented our own
recordings with those made by colleagues and deposited in the xeno-canto ornithological sound
collection (www.xeno-canto.org). Details of all 18 recordings, including localities, dates and
names of the sound recordists, can be found in Table S1 in the online Supplementary Materials.
Two major collections, National Museum of Natural History (Nederlands Centrum voor
Biodiversiteit (NCB) Naturalis, Leiden, Netherlands) and the Natural History Museum (Tring,
UK) provided the skins that were examined for a mensural analysis. In the analyses, 21 skins of
Cissa t. thalassina and 10 Cissa t. jefferyi were measured, with near-equal numbers (1:1) for
males and females for each taxon (Table S2).
Field observations were made during general and more specialised forest bird surveys on Java
between 1980 and 1997 (S. v. B), and excursions in 20022010 (J. A. E). Data on museum
specimens, publications in often obscure journals, and birding reports provided historical data on
distribution and biological information. Requests for eld data yielded a small additional number
of eld observations.
Bioacoustic analysis
Both analogue and digital recordings were converted into WAV format if they had not been initially
created in that format. Recordists used different equipment for sound recordings. However, we
consider any bias caused by equipment differences on parameter measurements to be negligible. For
instance, the level of variability in background noise and slight differences in note shape among
recordings from the same recordist are equivalent to the variability among recordings from different
recordists, indicating that differences in recording quality are much more important than equipment
differences. Furthermore, in many cases we analysed multiple recordings from several different
recordists for each taxon, which should remove any such bias. In each case, we made an attempt to
account for levels of sound pollution in our measurements by setting the background level equal.
We prepared and analysed sonograms of vocalisations using the program Syrinx version 2.6hby
John Burt (available at www.syrinxpc.com). Levels of background noise were set to an equal level,
otherwise default settings were employed. Cissa vocalisations are characterised by great variability and
a large individual repertoire of notes and song motifs. In order to carry out meaningful comparisons
among taxa, we classied sounds in each recording into one of twelve different motif types, each
designated by a unique letter ranging from A to L. Each motif type consists of one to several notes.
For each motif type in each recording, we then counted the number of times the motif was uttered, as
well as the number of notes the motif contained. We compared overlap in the presence of motif types
among taxa as well as overlap in the number of notes per motif type in each taxon.
Since many motif types in Cissa, especially the non-melodious ones, are characterised by
harmonics (component frequencies of waves that are an integer multiple of the fundamental
frequency), we also noted their presence or absence in the motifs of each recording and used
a binomial test to compare taxon-specic incidence of harmonics. In poor recordings, harmonics
can be difcult to detect even when present. However, virtually all our recordings were loud
enough for harmonics to show up on the sonogram in the presence of several multiples, and
multiple recordings were sampled for each taxon so we rule out recording quality as
a confounding factor in comparisons of harmonics. We measured three different frequency
parameters (highest frequency, lowest frequency and frequency range) as well as the duration for
each motif and compared them among all taxa.
Biology and conservation of Short-tailed Green Magpie in Java 3
One set of comparisons involved an across-taxon Kruskal-Wallis test and pairwise two-tailed
Mann-Whitney U-tests of the frequency parameters (not the duration) of all motifs measured for
each taxon, regardless of motif type, to test for taxon differences in general vocal pitch. In another
set of inter-taxon comparisons, we contrasted frequency parameters and duration of shared motifs
among taxa to check for overlap in measurements. Since only six motifs were shared amongst 23
taxa, and there were only 16 sample recordings per taxon per shared motif, sample size for this
second set of comparisons was too low for statistical analysis and overlap was only evaluated in
comparisons involving more than one sample recording in at least one taxon. All statistical
analysis was carried out using the program SPSS (SPSS Institute Inc., Chicago).
Biometric analysis
We measured eight biometric traits for 21 individuals of thalassina and 10 individuals of jefferyi
(each 50%maleand50% female): tail length, wing length, bill height, bill length, total length,
tarsus, tail/wing ratio and tarsus/wing ratio. Table 4 lists all measurements and specimen details
including museum voucher numbers. Female and male specimens were pooled for each species,
because sample sizes for signicance testing of sex-specic groups were too low, and because we did
not detect any sexual dimorphism. For each trait, we performed a two-tailed Mann-Whitney U-test
to examine differences between the two taxa. To increase the stringency of this test, we considered
a difference signicant at P # 0.01.Oncesignicant differences were detected between the two taxa,
we additionally examined if the measurements for a particular trait passed a second more stringent
signicance hurdle by assessing if the ranges of measurements for either taxon overlapped.
Phenotypic species delimitation test
We used the species delimitation criteria recently proposed by Tobias et al. ( 2010) to assess the
biological species status of thalassina and jefferyi based on the biometric, ecological, behavioural,
and plumage characters presented in this paper. This species delimitation test assesses phenotypic
differences between two taxa by assigning each character difference a score of 14, based on
whether the difference can be considered minor, medium, major or exceptional. The nal
score of a comparison is then applied against a threshold generated from a large global sample of
sympatric bird species; if it exceeds the threshold, phenotypic evidence can be seen to support
species status. For exact denitions of categories and assignment rules, see Tobias et al. (2010).
Results
Bioacoustics
For the Bornean jefferyi the call is described as not nearly so clear as that of C. minor, but is still
a feeble attempt at Ton-ka-kis’” (Whitehead 1893: 206). Interestingly, the main calls of the Javan
taxon thalassina appear to show a greater resemblance to the hypoleuca and chinensis complexes,
than to its present congener jefferyi. On Java, the Sundanese names èkèk gêling, kèkèt gêlèng,
dèrètdèt kêlèng , kèrèkèk kêlèng, cucak keling (WJ), and Javanese names dingdingbak (CJ), and
kekek kelang (Yogya) and variations (Bartels 1897-1931, Koningsberger 1907, van Oort 1910,
S. v. B. unpubl. data) closely describe the most stereotypic call of its large repertoire, which also
includes mimicking, and is accurately described as a nasal chiuu chiuu kèkèng ê ngliéng,
also uttered in ight (Bartels 1897-1931, J. H. Becking unpubl. data).
Vocal parameters for each taxon are specied in Table S1 in the online Supplementary
Materials. In our 18 recordings of four taxa, we found 12 different motif types (A-L), six of which
(A-F) were shared amongst more than one taxon. Fig. 1 depicts a typical example of each motif
type, and Fig. 2 shows the overlap in motif types among taxa, indicating that C. t. thalassina and
S. van Balen et al. 4
Figure 1. Twelve motifs found in Cissa vocalisations.
Biology and conservation of Short-tailed Green Magpie in Java 5
C. t. jefferyi only share a single motif type (D) that is also present in C. hypoleuca. On the other
hand, overlap between C. t. thalassina and C. hypoleuca is particularly pronounced, with four
shared motif types, three of which are exclusive to these two taxa.
In our assessment of whether the number of notes given by each taxon for each shared motif type
(i.e. motifs A-F) is approximately equal, we found that there is complete overlap in the number of
notes given by each taxon for motifs A, B, D, E and F. The only shared motif that showed no overlap
is C, which is characterised by 34 notes in C. t. thalassina and two notes in C. hypoleuca. However,
an increased sample size could easily establish overlap for the number of notes given for motif C by
these two species. All in all, we interpret the lack of inter-taxon differences in the number of notes
given for each motif type to corroborate that our denition of shared motif types is robust and that
only homologous vocalisations were grouped into common motif types.
Each vocalisation was scored for the presence or absence of harmonics, and a binomial test
showed that there is a signicant propensity for C. t. jefferyi to lack harmonics in its vocalisations
(two-tailed P-value , 0.001). No such propensity was found in the other taxa, although
C. hypoleuca exhibited a near-signicant propensity for uttering vocalisations containing
harmonics (two-tailed P-value 5 0.09), which with increased sampling may well turn out
to be a real vocal characteristic that sets this taxon apart.
We compared three frequency parameters in the overall vocal repertoire amongst each taxon,
regardless of motif type. A Kruskall-Wallis test (P 5 0.418) and pairwise Mann-Whitney U-tests
(results not shown) yielded no signicant differences among taxa in the highest vocal frequencies
of motif delivery. Equally, taxa did not differ signicantly in terms of the frequency range of
overall motifs uttered (Kruskal- Wallis: P 5 0.314; pairwise Mann-Whitney U-test: not shown).
The only frequency differences detected refer to the lowest frequencies (Kruskal-Wallis:
P 5 0.075) of overall motif delivery in C. t. thalassina, which were signicantly lower than in
C. t. jefferyi (two-tailed Mann-Whitney U-test: P 5 0.016), and almost signicantly lower than
in C. hypoleuca
(P 5 0.079) and C. chinensis (P 5 0.12). In contrast, no differences in lowest
Figure 2. Motif types unique to each taxon or shared among taxa; letters refer to motif types as
shown in Fig. 1.
S. van Balen et al. 6
frequencies were found in comparisons involving C. t. jefferyi, C. hypoleuca and C. chinensis, but
to the exclusion of C. t. thalassina.
As only six (AF) out of twelve motif types were shared among a range of 23 taxa, and since
motifs were represented only 16 times in each taxon (Table 2), sample size for motif-specic vocal
comparisons was too low for statistical analysis. Nonetheless, we performed a crude comparison
among taxa using all three frequency parameters and motif duration to check for general overlap in
these measurements. Wherever a shared motif was represented by more than one measurement in at
least one taxon in our sampling regime (i.e. in motifs A, B, D, E and F; Table 2), we ascertained
whether the value(s) for the other 12 taxa overlapped with this range. We found a complete overlap
of measurements for motifs D and E in all three frequency parameters and in motif duration
(Table 2). For motifs A and B, there was measurement overlap between the two taxa involved
(C. t. thalassina and C. hypoleuca) only at the highest frequency, but not in the other three vocal
parameters (Table 2). Similarly, in motif F, there was overlap among C. t. jefferyi, C. hypoleuca and
C. chinensis only at the lowest frequency, but not in the three remaining parameters. It is important
to note that a higher sample size may lead to the detection of ne-scale vocal differences between taxa
in overlapping parameters or conversely may show vocal overlap in parameters that seem to differ
among taxa using the current dataset. Overall, we expect many motifs to share the same vocal
properties among taxa, and we interpret this result as conrmation that we have generally classied
homologous vocalisations into equal motif categories. Even in homologous vocalisations that are
appropriate for comparative analysis, taxon-specic differences in some vocal parameters are expected
to involve at least a number of motif types, so differences in motifs A, B and F may well be real
indicators of vocal differentiation between Cissa taxa.
Morphology
Biometrics
Table 3 shows the measurements of eight biometric parameters of 21 specimens of thalassina and
10 jefferyi. Table 4 gives the mean values and P-values using a two-tailed Mann-Whitney U-test.
Bornean jefferyi has a signicantly shorter wing length than thalassina (although their
measurements display some overlap), and a comparatively even shorter tarsus length with no
overlap in measurements. Accordingly, the tarsus-wing ratio showed signicant differences
although measurements overlapped. In terms of tail length, size dimensions are reversed, as
jefferyi displays signicantly longer measurements than thalassina, with no apparent overlap,
and intermediate between thalassina and the other species of green magpie (Tables 1 and 3).
Consequently, tail-wing ratios also differ signicantly between both taxa, with no overlap in
measurements. Whilst bill length does not differ signicantly between the two taxa, bill heights
are signicantly different between the two species with no overlap in measurements, resulting in
Table 2. Biometrics of two taxa of Short-tailed Green Magpie (all measurements in mm, unless indicated
otherwise; from skins stored in the Leiden Museum, mostly thalassina, and Tring, mostly jefferyi).
Mann-Whitney U-test P-values are given.
Wing L Tail L Bill L Bill H Tarsus Total L
(cm)
Tarsus/
wing
Tail/
wing
thalassina
(n 5 21)
mean 137.2 107.235.915.442.326.30.31 0.78
SD 3.04.82.10.81.41.50.01 0.04
range 133-142 101-118 32.5-41.013.9-17.040.1-45.024.5-30 0.29-0.33 0.75-0.87
jefferyi
(
n 5 10)
mean 132.8 124.934.312.739.427.40.30 0.94
SD 2.14.11.60.81.30.50.02 0.02
range 130-136 118-129 32.2-36.711.0-13.637.7-42.327-28 0.29-0.32 0.90-0.97
P 0.0006 ,0.0001 0.0404 ,0.0001 0.0001 0.0193 0.0099 ,0.0001
Biology and conservation of Short-tailed Green Magpie in Java 7
an obviously ner bill in jefferyi (Fig. 3b). This divergence in tail length and bill shape may
indicate slight differences in ecological adaptations. Finally, there is no signicant difference in
total length between jefferyi and thalassina. Male and female measurements were always pooled
in each taxon, since limited sexual differences were detected (data not shown).
Table 3. Descriptive notes of the plumage and soft parts of C. t. thalassina and C. t. jefferyi.
Trait thalassina jefferyi Interpretation of
difference (as per
Tobias et al. 2010)
Score
Tertials more extensively
light green (white
in museum specimens);
base of outer webs
reddish brown, outermost
tertiary with the outer web
near tip also reddish brown,
in some cases with only two
pale spots at the tip (Kuroda
1933; pers. obs.)
Inner secondaries
greenish white,
except on outer web,
which is for the most
part claret-red, the
outermost one with a
oblique pale tip (Whitehead
1893; pers. obs.)
Considerable variation
in pattern in both
taxa is not gender-
specic but individual
or age-related. This
difference is medium,
as it involves a different
tone of a distinctly-
demarcated body part
2
Rectrices uniform bluish green, with
diffusely pale tips only to
the outermost rectrices
rectrices have white tips
and dark subterminal bars.
major, as it involves a
different pattern
(barring versus no
barring) in a tract
of feathering
3
Eyes red (Vorderman 1886a) to
bright coral red
(Kuroda 1933)
white with a faint pink
tinge round the pupil
(Whitehead 1893)
Note that contra dos
Anjos (2009) orbital
ring in jefferyi is not
light blue but crimson
red as in thalassina
(see photos www.oriental
birdimages.org. Iris colour
difference is major as it
involves a different
bare-parts coloration
3
Table 4. Interpretation of biometric differences according to criteria in Tobias et al. (2010); note that body
ratios are not listed since they co-vary with their constituent parameters.
Biometric difference
between jefferyi and thalassina
Effect size (Cohensd)
and interpretation (as per
Tobias et al. 2010)
Score
Tail longer in jefferyi d 5 3.99, i.e. medium 2
Tarsus longer in thalassina d 5 2.14, i.e. medium 0
Wing longer in thalassina d 5 1.64, i.e. minor (score 1),
but cap on # 2 biometric traits
0
Bill higher in thalassina d 5 3.47, i.e. medium (score 2),
but cap on # 2 biometric traits
2
Bill longer in thalassina d 5 0.89, i.e. minor (score 1),
but co-varies with bill height
0
Body longer in
jefferyi d 5 1.38, i.e. minor, but co-varies
with tail length
0
S. van Balen et al. 8
Weight of all taxa is about the same, 120133 g(chinensis), 125 g(hypoleuca), 125 g
(thalassina / jefferyi), although this dataset is far too small for statistical analysis.
Plumage and soft parts
Fig. 3 shows representative adult specimens of both Javan and Bornean Short-tailed Green
Magpie. Table 3 provides descriptions of the body parts that are most strikingly different between
these two taxa.
Figure 3. a-c. Specimens (in NCB Naturalis, Leiden) of Cissa t. thalassina (above) and
C. t. jefferyi (below) showing the differences in tail length and tertial pattern (a, dorsal), bill
shape and size (b, lateral), and pattern of under tail (c, ventral.) (Photos: S. v. B).
Biology and conservation of Short-tailed Green Magpie in Java 9
Phenotypic species delimitation test
We carried out a novel species delimitation test introduced by Tobias et al. (2010) that interprets
phenotypic taxon differences related to biometrics, coloration, bioacoustics, ecology and
behaviour, and assigns scores from zero to four according to strict criteria on the level of
differentiation in those traits. Based on a comparison with a large pool of pairs of known sister
species, Tobias et al. (2010) consider the score of 7 a threshold for recognition as a biological
species. Table 3 lists the differences in coloration between thalassina and jefferyi and indicates
a total score of 8 for colour traits, which already surpasses Tobias et al.s(2010) species threshold
and indicates that the two taxa merit recognition as species based on coloration alone.
A fourth trait has been given by dos Anjos (2009) as subspecically diagnostic, i.e. a yellow
wash on crown and underparts of the Javan birds. As there is only a very slight difference in green
between the two taxa, mainly on the head (see Figure 3) we did not consider it in our analysis.
Moreover, Vorderman (1886) who described a freshly killed bird from Mt Salak, west Java, makes
no mention of a yellow wash: ...plumage bright pale blue-green, that has a pronounced green
wash on head, belly and anks.
Table 4 lists the interpretation of biometric differences according to the criteria set forth by
Tobias et al. (2010 ) and indicates an additional score of 4, which adds up to a score of 12, well
beyond the species threshold. Ecological or behavioural differences between the two taxa appear
to be insignicant, although there is a difference in altitudinal range (see below), and the Javan
birds seem to venture out of the forest (see below), resembling Cissa chinensis rather than the
Bornean Short-tailed, that never leaves true forest (Whitehead 1893).
As far as vocal differentiation between jefferyi and thalassina is concerned, the extensive
complexity of vocal characters and the abundance of motif types as well as the difculty in
classifying motif types into songs and calls make the application of Tobias et al.s(2010)
criteria to bioacoustic data in the genus Cissa challenging. In our vocal analysis of taxon
differences (see above), we have dealt with these difculties by showing that thalassina
is vocally
closer to C. chinensis than to jefferyi, and by focusing on a comparison of motif types, but it is
not straightforward to adjust this type of analysis to the methodology put forth by Tobias et al.
(2010). Therefore, we here abstain from applying their phenotypic test to vocal characters in
jefferyi and thalassina, while noting that inclusion of the extensive vocal differences between
homologous vocalisations detected by us (see above) would certainly further increase the test
score. Since the test diagnostic is already at 12 and well beyond the species threshold at 7 after
only biometric and colour characters are included, we deem the incorporation of vocal characters
unnecessary for the purposes of this test.
Discussion
Vocal differences
Cissa magpies belong to the oscine songbirds, in which vocalisations are a learned rather than an
inherent trait. In addition, they are great vocal imitators and are characterised by an astounding
vocal repertoire. Consequently, they are a difcult subject for vocal analysis, since bioacoustic
parameters must be compared amongst homologous vocalisations only. With the wide range of
different motifs given by each Cissa taxon, the difculty lies in the assignment of vocalisations to
correct homologous motif classes. Using a range of 18 recordings from four taxa, but with
a special emphasis on C. t. thalassina, C. t. jefferyi and C. hypoleuca, we have classied Cissa
sounds into 12 motif types (AL) depicted in Fig. 1 six of which (AF) we believe to be shared
amongst 23 Cissa taxa. We believe that our assignment of vocalisations into homologous motif
types has been successful, because we have detected almost no discrepancies in the number of
notes given per motif type amongst different taxa. Equally, when comparing each shared motif
type (A F) among different taxa in terms of motif durations and three different frequency
parameters, we found substantial overlap in measurements between taxa (Table 1). No such
S. van Balen et al. 10
overlap would be expected in categories that consist of non-homologous vocalisations
inaccurately classied into the same motif types. Even so, vocal differentiation amongst taxa is
expected to produce measurement differences in at least a number of parameters and motif
classes, which conforms to our observation of limited overlap between taxa in some vocal
parameters in motifs A, B and F.
C. t. jefferyi and C. t. thalassina were found to share only one motif type (D), which is
probably ancestral because it is not exclusive to them, having been found also in C. hypoleuca
(Fig. 2). In contrast, sharing of motif types was greatest between C. t. thalassina and C. hypoleuca
(Fig. 2). Further vocal evidence that C. t. jefferyi and C. t. thalassina exhibit substantial vocal
differences is the nding that C. t. jefferyi was the only one of all four taxa that is characterised
by a signicant lack of harmonics in its vocal delivery. Harmonics create a particular vocal timbre
that often sounds scratchy or non-melodious to the human ear, and they are regularly employed
by C. t. thalassina as well as the two other Cissa species investigated. Therefore, C. t. jefferyi
sounds considerably more melodious than the other taxa in its overall motif delivery. Last but not
least, we found that the overall lowest frequency in motif delivery regardless of motif type is
considerably lower-pitched in C. t. thalassina than in the other species, especially (and
signicantly so) in comparison to C. t. jefferyi.
Although the vocal complexity of Cissa vocalisations renders bioacoustic analysis challenging,
it is clear that the vocal repertoire and a number of general vocal qualities of C. t. thalassina differ
greatly from its supposed conspecic C. t. jefferyi, and that C. t. thalassina may in fact be vocally
more similar to C. hypoleuca. This similarity between the Javan and the Indochinese taxa
supports biogeographic ndings in other bird species that Javan fauna may be more closely related
to species from the subtropical monsoon forests north of the Sundaic rainforest zone (Medway
and Wells 1976, Wells 1985, Holmes 1985). Whereas these are exclusively lowland species, there
are examples of montane bird species that have also been separated sufciently long for speciation
and whose distributions show analogies with that of the magpie, i.e. Javan Tesia Tesia
superciliaris, and Spotted Crocias Crocias albonotatus, all restricted to the western half of Java
and with their closest relatives in mainland Asia, not on Sumatra or Borneo. Other west Javan
endemics have allospecies on Sumatra (e.g. Javan Trogon Apalharpactes reinwardti and Javan
Cochoa Cochoa azurea).
Morphological differences
Statistical analysis of biometric differences demonstrates that thalassina is a signicantly shorter-
tailed bird than jefferyi, even though its tarsus and wings are signicantly longer. In addition, the
two taxa exhibit an important divergence in bill morphology, with thalassina having a slightly
longer and distinctly more massive bill than jefferyi. These biometric differences may reect
adaptations to slightly different life histories, but more research is needed to conrm this. We also
document important differences in coloration, especially in brightly-coloured parts of the body (iris,
wing panel, tail) that may serve a signalling function. In summary, our morphological data support
our bioacoustic analysis in that jefferyi and thalassina should be afforded biological species rank.
Phenotypic species delimitation test and taxonomic recommendation
Even though our application of Tobias et al.s(2010) species delimitation test did not include our
bioacoustic dataset (see Results), and despite the fact that its inclusion would have further
increased the test diagnostic, we arrived at a score of 12, well beyond the species threshold of 7.
This high score conrms our conclusion that jefferyi and thalassina are well-differentiated taxa
that deserve to be recognised at the biological species level. Perhaps most importantly, this
conclusion is based on the independent documentation of profound differences in vocalisations,
visual cues as well as structural parameters that may reect adaptations to the environment.
Biology and conservation of Short-tailed Green Magpie in Java 11
Ecology
Distribution and habitat
The elevational distribution of C. t. thalassina of 1,000 - 1,200 m as reported in the latest standard
works (dos Anjos 2009) does not fully match our ndings. Although occasionally encountered in
lowland forest (Koningsberger 1915), the main distribution is in submontane and montane forests
at 5002,000 m (Sody 1956). Appendix S1 in the online Supplementary Materials lists all records
of Cissa t. thalassina that we could nd. Three specimens in RMNH and MZB without dates or
exact localities (Bogor, Sukabumi and Priangan) have been omitted.
Bornean and Javan Green Magpies occupy largely overlapping altitudinal ranges, respectively
3052,735 and 5002,000 m. The former seems to occur higher up in the hills, possibly because of
competitive exclusion with its congener C. chinensis in the lowlands, as nowhere do they seem to
co-occur (Whitehead 1893). There is no obvious reason why the apparently more stenotopic
Javan birds do not occur above 2,000 m, where no competitors occur, and theoretically its larger
size should actually be in its favour (James 1970). This anomaly may be partly explained by the
massenerhebung effect of the 4,101 m high Mt Kinabalu, as compared to the smaller mountains
in western Java, the highest of which is the 3,418 m Mt Slamet, but most are c.3,000 m or lower.
Bartels (1931) described its habitat in and around a tea plantation on the south-western slopes of
Mt Patuha, where during their raiding parties the magpies venture out far into the tea gardens;
they prefer the forest fringes along the rivers.
Food
The old names Hunting Crow or Hunting Cissa (Madge and Burn 1994) very aptly describe its
voracious nature. They are found in troops, or seasonally in pairs (Koningsberger 1915), not
uncommonly accompanied by Rufous-fronted Laughingthrush Garrulax rufrons (Konings-
berger 1907), and often found near mixed bird parties (Delsman 1927).
Table 5 shows the items found in the stomach content of 34 specimens (Vorderman 1886,
Bartels 1897-1931, Sody, in Becking 1989). Throughout the year invertebrates form the most
important element. A variety of prey items has been found in stomachs: snails; crustaceans:
craysh Astacidae (Decapoda), pill bugs Armadilliidae (Isopoda); insects: cockroaches Blattidae
(Dyctyoptera), grasshoppers (Orthoptera), may-beetles Scarabaeidae, weevils Curculionidae,
Chalcothea spp. Cetoniidae, horned beetles Cerambycidae, click beetles Elateridae (Coleoptera),
cicadas (Homoptera), caterpillars (Lepidoptera), large ants Formicidae (Hymenoptera). Larger
vertebrate prey (small birds, lizards, including their eggs, tree frogs, and snakes) constitutes
a large part in rst three months of the year only, largely coinciding with the breeding season.
Breeding
Although data are scarce and conclusions cannot be reliably drawn, it appears that breeding takes
place during most of the year with a preponderance for the wettest months, i.e. October April in
Table 5. Food items in stomach content of Cissa thalassina (from Vorderman 1886; M. Bartels 1897-1931).
I: Jan-Mar, II: Apr-Jun; III: Jul-Sep; IV: Oct-Dec.
I II III IV
n samples 10 11 2 12
Invertebrates 18 24 7 20
Vertebrates 13 1 1 5
Fruits 100 2
S. van Balen et al. 12
west Java (Voous 1950): Jan (3), Feb (1), Mar (1), Apr ( 3), Sep (1), Dec (2) (after data from Bartels
1897-1931, Hoogerwerf 1949, 1950, Hellebrekers and Hoogerwerf 1967, J. H. Becking unpubl.
data). Birds are freshly moulted at the end and beginning of the year (Bartels 1902).
Meyer (1884) reported a ...cup-shaped nest on the thin twigs of a large-leaved tree, consists of
a base of stronger stalks or branches, then tendrils and thin twigs, intertwined with many dry
leaves of bamboo, rice etc; inside lined with black thin roots; 80 mm high, 170-180 mm wide,
inner cup 65 mm deep and 110 mm wide.. Bartels (1897-1931) ... found its nest twice on thin
trees in a tree fork close to the trunk, of rather solid built, but not very large in relation to birds
size .... Hoogerwerf (1950):...usually not high above the ground (36 m)...in not thick
branches...base and outside consists of dry leaves, both from trees and rattan etc. Nest cup lined
with plant parts looking like thin, dark rootlets, and petioles, stems, etc.... Becking (unpubl. data)
reported a nest in a Tarenna incerta tree at 2.5 m above the ground in a Manglietia experimental
plot, another in a small tree in undergrowth at 3 m above the ground in primary forest.
Clutch size is one egg (n 5 1) or two (n 5 7) (Hoogerwerf 1949, Hellebrekers and Hoogerwerf
1967). The egg is described as oval, coarse-grained, smooth, and moderately glossy, with
yellowish-white ground colour with few grey violet primary stains, and marked on the entire
surface with uniformly distributed smaller reddish-yellow secondary stains; also this egg shows
the close relationship with
Cissa chinensis (Kuschel 1895). Eggs of C. t. thalassina (n 5 17;
Hoogerwerf 1949, Hellebrekers and Hoogerwerf 1967, Becking unpubl. data) average 32.78 mm
(31.1-34.3 mm) x 22.61 mm (range 22.023.30).
It has been frequently reported that incubating birds with young or eggs are very steady,
... leaving their nest only when the nest tree is climbed... (Bartels 1897-1931; J.H. Becking
unpubl. data); this certainly makes them vulnerable to bird trapping.
Conservation
Bird trade
According to Rutgers and Norris (1977), they do not appear often in collections, and in 1861 the
taxon was rst imported to London. The magpie is a moderately popular cage bird on Java, despite
the quick loss of its bright green colour in captivity, but possibly compensated by its loud and clear
calls, making it attractive for local bird fanciers. Numbers seen on local bird markets have always
been small and during 19791986 they were rather erratically seen for sale on the bird markets in
Bandung and Bogor (S. v. B pers. obs.), i.e. not always present and mostly in singles: (i) Many
(25125 birds, relatively expensive) in October-May 1978, Bandung (Iskandar 1980). (ii) A
comprehensive survey of the Yogya bird market in February 1979 counted a single bird (van
Balen et al. in prep.). (iii) Regular visits to the bird market in Bogor in 1979-81 yielded only few
records; in Bandung 198186, few each time. (iv) None were seen among 150,000 birds on
a Jakarta bird market in December 1987 (Basuni and Setiyani 1989). (v) A study into the bird
trade in Indonesia in 199293 found C. t. thalassina in 25 of 39 surveys of mainly Javan bird
markets; it was also reported that 320 were authorised for export between August-December
1992 (Nash 1993). (vi) Often seen on bird markets in the past, but now very rarely, and currently
prices have been sky-rocketing to Rp 1,200,000 per bird (R. Sözer in litt. 2011), which is more
than the local minimum wage per month (Wordpress 2011).
The relative popularity of green magpies in general is indicated by the moderately large
numbers of Cissa chinensis found during a bird market survey in 19972001 in Medan: between
121 and 264 (Shepherd et al. 2004) meaning an average of 1020 birds each survey, suggesting
a certain popularity of green magpies, and in February 1995, three
Cissa chinensis were seen
offered for sale in the west Javan town of Purwakarta (S. v. B. unpubl. data).
For Mt Halimun, Riffel (1991) reports that many are caught, as also communicated in April
1995 by Suandi (Carucub village) to S. v. B. In the Lumping (Dieng Mts) in the mid 1990s bird
catchers were mostly people of the village, but also a trapper from western Java who specialised in
Biology and conservation of Short-tailed Green Magpie in Java 13
green magpies was reportedly active in the area. These trappers were only active in October and
November when the main bait to catch forest birds, winged termites (laron), were available in
abundance.
Habitat fragmentation
Most forest up to 1,000 m and locally up to 1,500 m has disappeared on Java (van Balen 1999), thus
largely affecting the range of the magpie. No magpies are known from montane forest patches that
are small and have been isolated since prehistoric times, such as Mts Karang, Muriah, Ciremai, and
Ungaran, indicating that the species is sedentary. This might also explain why this species never
occurred in the eastern half of Java.
Although classied by Wells (1985) as dependent on montane habitat, they might be better
regarded as one of his lowland slope specialists. With the near-total deforestation of Javas
lowlands and ongoing encroachment beyond 1,000 m and even 1,500 m, this taxon faces a real
risk of local or even overall extirpation, as it is being locked up in increasingly narrow forest
bands (van Balen 1988). Interestingly, the Bornean jefferyi has a considerably wider range, from
305 to 2,735 m, though rarely below 1,400 m, where it overlaps at lower altitudes, 305-1,530 m,
with the Common Green Magpie Cissa chinensis minor, but both species appear to be mutually
exclusive on Mt Kinabalu (Whitehead 1893) above and below 1,000 m.
Status assessment
The taxon jefferyi appears to be secure in its remote haunts in the interior of Borneo, especially in
well-protected reserves such as Kinabalu National Park. The following discussion on conservation
therefore solely refers to the Javan Green Magpie.
Three parameters for IUCN threatened category thresholds (Collar et al. 1994, IUCN 2001,
BirdLife International 2001) were assessed for the Javan Green Magpie: (i) population decline,
(ii) population size, and (iii) small range size. (i) The observation that few or no green magpies
have been seen in the past 25 years, even in areas where they used to be seen quite regularly (Mts
Halimun-Salak, and Mts Gede-Pangrango), and the nearly total disappearance from local bird
markets where they were seen more or less frequently in the past, suggests a serious decline in
numbers, which certainly exceeds 80% in the past 10 years. As shown, they have probably been
completely extirpated from many of the sites where they were last recorded in the 20
th
century.
(ii) Populations at the 14 sites where there is a potential chance of their present survival must
certainly be very small, probably not exceeding one or two dozen individuals. The global wild
population size therefore probably does not exceed 100 and is quite possibly below 50 individuals.
Excessive capture for the bird trade and habitat destruction are the ultimate causes of the extreme
rarity of the magpies. The survival of small remaining populations is now jeopardised by the fact
that catchers specialise in one or more species. This inevitably means that local populations are
specically targeted, with an increased risk that the last remaining birds in the wild are extirpated
sooner or later. (iii) Their extent of occurrence (global range) is probably c.2,410 km
2
. The
ongoing deterioration of suitable habitat has undoubtedly caused the shrinking of its range from
nine to four, or fewer, localities.
The area of occupancy (actual area inhabited) of 1,680 km
2
is calculated from the total area of
localities where the magpie has been seen since 2000 (Table 6). This gure is more than likely too
optimistic, given the lack of more recent records, and the fact that only part of these areas consists
of suitable habitat. Moreover, only four localities are reserves that are moderately or hardly
fragmented, enjoy sufcient protection against hunting and habitat destruction, and where
observations date from this century.
Based on the above observations, we note that the Javan Green Magpie fulls four criteria for
Critically Endangered status:
S. van Balen et al. 14
- Criterion A2a: a projected decline of $ 80% over 10 years based on observation;
- Criterion C1: a global population size of # 250 mature individuals that are
declining at $25%;
- Criterion C2a: a global population size of # 250 mature individuals that are
severely fragmented, with # 50 individuals per sub-population;
- Criterion D: a global population size that may well be # 50 mature individuals.
Measures taken
Cissa thalassina has been observed in only four localities in the last 10 years. These are Mts
Halimun-Salak, Mts Gede-Pangrango, Gunung Simpang and Mt Merapi. The rst and second
sites are more or less well-established national parks, where despite the huge importance of the
endemic biodiversity they support, much encroachment (agriculture, logging, mining, bird-
catching) occurs along their borders. Gunung Simpang is a strict nature reserve, whereas Mt
Merapi was given national park status a few years ago, but its efcacy is debatable, as there is
much resistance from local communities, and recent volcanic eruptions have destroyed much of
the natural forest.
Measures proposed
(i) The Javan Green Magpie qualies for immediate protection because of its precarious current
situation. Any ofcial protection measures however have to be taken with the greatest care, as
drawing too much attention could easily boost its market price as a cage bird, as has happened
previously with endangered species (Nijman et al. 2009). (ii) Law enforcement and awareness
programmes in the last refuges of the magpie, Mts Halimun-Salak, Mts Gede-Pangrango,
Gunung Simpang and Mt Merapi protected areas should be intensied, and focused on proper
protection of the forest at the lower to mid-elevations. (iii) Any Javan Green Magpies that are
encountered in captivity should be immediately rescued for either a captive breeding programme
or release into the wild. Only birds that are unsuitable for release, for instance by having been in
captivity too long (as indicated by fading of the green plumage into blue) should be considered for
a captive breeding programme. Currently a feasibility study for a breeding programme in the
Cikananga wildlife rescue center at Sukabumi, West Java, is supported by Chester Zoo (UK)
(R. Sözer in litt. 2011). Release attempts should be undertaken into their areas of origin, or in
areas where re-stocking is preferable, but only provided that these actions are backed by increased
law enforcement and awareness programmes, as otherwise the released individuals may well be
Table 6. Forest blocks in West and Central Java with recent and historical records of Cissa thalassina.
Abbreviations: NP, National Park; NR, Nature Reserve; PF, Protection Forest. Fragmentation score: 1, one
large compact area; 2, several medium-sized, interconnected forest areas; 3, several small to intermediate
areas, with or without adjacent smaller areas.
Status Area (km
2
) Alt. range (m asl) Fragmen-
tation
Most recent
record
Mts Halimun-Salak NP 500 400 2,210 1 2005
Jampang Kulon - 100 0 400 3 1906
Mts Gede-Pangrango /
Megamendung
NP 200 500 3,019 2 2002
North Parahyangan PF/NR 100 900 2,018 3 1941
South Parahyangan PF/NR 900 300 2,622 2 2006
Pembarisan Mts PF 130 300 1,351 2 1994
Mt Slamat PF 150 700 3,418 1 1917
Dieng Mts PF 250 250 2,565 2 1995
Mt Merapi NP 80 1,000 3,142 2 2005
Biology and conservation of Short-tailed Green Magpie in Java 15
illegally captured again shortly after release. (iv) Surveys should be undertaken in remaining
forest patches with extensive suitable habitat, that have been undersurveyed but where the
presence of green magpies is expected, e.g. Gunung Sawal (5,400 ha, 6001,764 m) and Gunung
Ciremai (12,000 ha, 1,0003,078 m). Areas where magpies were historically known to occur
should also be surveyed.
Conclusion
The signicant differences in biometrics and coloration as well as strong vocal differences warrant
an upgrading of both the Bornean and Javan subspecies of Short-tailed Green Magpie to species
status. We propose the English names Bornean Green Magpie Cissa jefferyi and Javan Green
Magpie Cissa thalassina.
Only four or fewer localities in western Java appear to harbour Javan Green Magpie. Their
numbers must have seriously declined in the past 25 years; and its present extent of occurrence is
little more than 2,100 km
2
, whereas in its area of occupancy only a fraction of the original
population may remain. Pending specialised surveys in potential areas, we propose the status of
globally Critically Endangered for the Javan Green Magpie, based on IUCN criteria.
Supplementary Material
The supplementary materials for this article can be found at journals.cambridge.org/bci
Acknowledgements
Thanks are due to Vincent Nijman, Pupung Nurwatha, Adhy Maruly, Prayudhi, Indra Ferdinand,
Nick Brickle, Pete Wood, David K. Bishop, Frank Lambert and Resit Sözer for sharing their
records of Green Magpie on Java. Thanks also go to Steven van der Mije (NCB Naturalis, Leiden),
Mohammad Irham (Museum Zoologicum Bogoriense at Bogor, Indonesia) and Mark Adams
(British Natural History Museum at Tring, UK) for access to their bird collections. Dave Farrow,
Craig Robson, David Edwards, Brian Cox, Arnold Meijer, Nick Athanas, Rob Hutchinson, Mike
Nelson and Frank Lambert are thanked for providing their sound recordings through the online
database http://www.xeno-canto.org.
References
Andrew, P. (1985) An annotated checklist of
the birds of the Cibodas-Gunung Gede
Nature Reserve. Kukila 2: 1028.
dos Anjos, L. (2009) Family Corvidae
(Crows). Pp. 494640 in J. del Hoyo,
A. Elliott and D. A. Christie, eds. Handbook
of the birds of the world. Volume
14
. Bush-
shrikes to Old World sparrows. Barcelona:
Lynx Edicions.
van Balen, J. H. (1918) De dierenwereld van
Insulinde. II. De vogels. Zutphen, The
Netherlands: Thieme.
van Balen, S. (1984) Comparison of bird counts
and bird observations in the neighbourhood
of Bogor (Indonesia). Student Report.
Utrecht: State University of Utrecht.
van Balen, S. (1988) Forest fragmentation and
the survival of forest birds in Indonesia:
a preliminary report. Pp. 115165 in Proc.
Seminar Nachkontakt DAAD, Bogor 9-11
December 1987.
van Balen, S. (1999) Birds on fragmented
islands: persistence in the forests of Java
and Bali. PhD dissertation. Wageningen:
Wageningen University.
Bartels, M. E. G. (1902) Zur Ornis Java.
Natuurk. Tijdschr. Ned-Indië 61: 129172.
Bartels, M. (1906) Systematische Übersicht
meiner Java-Vögel. J. Orn. 54: 383407,
497519.
Bartels, E. (1897-1931) Vogels van Kole Beres.
Natuurk. Tijdschr. Ned-Indië 91: 308348.
S. van Balen et al. 16
Basuni, S. and Setiyani, G. (1989). [Bird
trading at the Pasar Pramuka, Jakarta and
the bird catching techniques] Media Kon-
servasi 2 (2): 918. (In Indonesian, with
English summary).
Becking, J. H. (1989) Henry Jacob Victor Sody
(
1892-1959
). His life and work. Leiden, The
Netherlands: Brill.
BirdLife International (2001) Threatened
birds of Asia. The BirdLife International
Red Data Book. Cambridge, UK: BirdLife
International.
Collar, N. J., Crosby, M. J. and Statterseld,
A. J. (1994) Birds to watch
2
. The world list
of threatened birds. Cambridge, UK: Bird-
Life International. (BirdLife Conservation
Series 4).
Chasen, F. N. (1935) A handlist of Malaysian
birds. Bull. Rafes Mus. 11: 1389.
Delacour, J. (1929) Révision du genre Cissa.
LOiseau et R.F.O. 10: 112.
Delsman, H. C. (1927) Vogelleven in het
oerbosch II. Trop. Nat. 16: 8289.
Dickinson, E. C., Eck, S. and Martens, J.
(2004) Systematic notes on Asian birds.
44. A preliminary review of the Corvidae.
Zool. Verh. Leiden 350: 85109.
Forbes, H. O. (1885) A naturalists wander-
ings in the Eastern Archipelago. London:
Sampson Low, Marston, Searle &
Rivington.
Goodwin, D. (1976) Crows of the world.
London, UK: British Museum (Natural
History).
Goodwin, D. (1986) Crows of the world. 2
nd
edition. London, UK: British Museum
(Natural History).
Hellebrekers, W. P. J. and Hoogerwerf, A.
(1967) A further contribution to our
oological knowledge of the island of Java
(Indonesia). Zool. Verh. Leiden 88: 1
164.
Holmes, D. A. (1985) Ornithological reec-
tions: the Thai connection. Voice of Nature
28: 1315.
Hoogerwerf, A. (1948) Contribution to the
knowledge of the distribution of birds on
the island of Java. Treubia 19: 83137.
Hoogerwerf, A. (1949) Bijdrage tot de oölogie
van Java. Limosa 22: 1279.
Hoogerwerf, A. (1950) The avifauna van
Tjibodas en omgeving, inclusief het natuur-
monument Tjibodas-Gn. Gede (West-Java).
Limosa 23: 1156.
Howard, R. and Moore, A. (1980) A complete
checklist of the birds of the world. London,
UK: Macmillan.
Iskandar, J. (1980) [Study of birds in several
village areas in the Citarum catchment
area]. Student Report. Bandung: Padjad-
jaran University. (In Indonesian).
IUCN (2001) IUCN Red List categories and
criteria version
3.1
. URL: http://www.iucn
redlist.org/technical-documents/categories-
and-criteria/2001-categories-criteria
James, F. C. (1970) Geographic size variation
in birds and its relationship to climate.
Ecology 51: 365390.
Koningsberger, J. C. (1907) Zoologische wan-
delingen te Tjibodas. II. Boschvogels. Teys-
mannia 18: 6776.
Koningsberger, J. C. (1915). Java, zoölogisch
en biologisch. Buitenzorg, The Netherlands:
Department Landbouw, Nijverheid & Handel.
Kuroda, N. (1933) Birds of the island of Java
1. Passerines
. Tokyo: published by the
author.
Kuschel, M. (1895) Zur Oologie Javas. Orn.
Monatsber. 3: 153156.
Madge, S. and Burn, H. (1994) Crows and
jays. London, UK: Helm.
Medway, Lord and Wells, D. R. (1976) The
birds of the Malay Peninsula. Volume
5
Conclusion, and survey of every species.
London and Kuala Lumpur: Witherby &
Penerbit Universiti Malaya.
Nash, S. V. (1993) Sold for a song. The trade
in Southeast Asian non-CITES birds. Traf-
c Southeast Asia.
Nicholson, F. (1882) Supplementary notes to
the list of birds collected by Mr. H.O.
Forbes in the island of Java. Ibis 24:
6671.
Nijman, V., Shepherd, C. R. and van Balen, S.
(2009) Declaration of the Javan Hawk-eagle
as Indonesias National Rare Animal im-
pedes conservation of the species. Oryx 43:
17.
van Oort, E. D. (1910) List of a collection of
birds from western Java and from Krakatau.
Notes Leyden Mus. 32: 105166.
Peters, J. L. (1962) Check-list of birds of the
world. Vol. 15. Cambridge, MA: Harvard
Museum of Comparative Zoology.
Biology and conservation of Short-tailed Green Magpie in Java 17
Riffel, M. (1991) Gunung Halimun - ein
positives Naturschutzbeispiel. Mitt. Zool.
Gesellschaft für Arten- und Populations-
schutz e.V 7 (2): 12.
Robinson, H. C. and Kloss, C. B. (1924)A
nominal list of the birds collected on Java.
Treubia 5: 267298.
Rutgers, A. and Norris, K. A. (1977) Ency-
clopaedia of aviculture. Vol. 3. Poole,
Dorset, UK: Blandford Press.
Scharringa, J. (2005) Birds of tropical Asia
3
.
Enschede, The Netherlands: Bird Songs
International.
Shepherd,C.R,Sukumaran,J.andWich,S.A.
(2004). Open season: an analysis of the pet
trade in Medan, Sumatra
1997-2001
. Trafc
Southeast Asia.
Sibley, C. G. and Monroe, B. L. (1990).
Distribution and taxonomy of birds of the
world. New Haven, CT and London, UK:
Yale University Press.
Sodhi, N. S., Soh, M. C. K., Prawiradilaga,
D. M., Darjono and Brook, B. W. (2005)
Persistence of lowland rainforest birds in
a recently logged area in central Java. Bird
Conserv. Internatn. 15: 173191.
Sody, H. J. V. ( 1956) De Javaanse bosvogels
(Javanese forest birds). Indonesian J. Nat.
Sci. 112: 153170.
Sözer, R. and Nijman, V. (1995) Behavioural
ecology, distribution and conservation of
the Javan Hawk-eagle Spizaetus bartelsi
Stresemann,
1924
. Amsterdam, The
Netherlands: Zoologisch Museum, Univer-
siteit van Amsterdam. (Verslagen en Tech-
nische Gegevens 62).
Stresemann, E. (1930) Eine Vogelsammlung
vom Vulkan Papandajan (West-Java).
Treubia 12: 425430.
Tobias, J. A., Seddon, N., Spottiswoode, C. N.,
Pilgrim, J. D., Fishpool, L. D. C. and Collar,
N. J. (2010) Quantitative criteria for species
delimitation. Ibis 152: 724746.
de Visard de Bocarmé, J. (1829) Quelques
observations faites à Java par le comte J.
de Visard de Bocarmé sur les moers et
habitudes doiseaux déjà projurés ou décrits
dans divers ouvrages. Manuscript in NCB
Naturalis Leiden, The Netherlands.
Vorderman, A. G. (1886) Bijdrage tot de
kennis der avifauna van den berg Salak.
Natuurk. Tijdschr. Ned-Indië 46: 304414.
Vorderman, A. G. (1887) Bijdrage tot de kennis
van de avifauna der Preanger Regentschap-
pen langs de Wijnkoopersbaai (West-Java).
Natuurk. Tijdschr. Ned-Indië 46: 6590.
Walters, M. (1980) The complete birds of the
world. London, UK: David and Charles.
Wells, D. R. (1985) The forest avifauna of
Western Malesia. Pp. 213232 in A. W.
Diamond and T. E. Lovejoy, eds. Conser-
vation of tropical forest birds. Cambridge
UK: International Council for Bird Preser-
vation. (ICBP Technical Publication 4).
Whitehead, J. (1893) Exploration of Mount
Kina Balu, North Borneo. London, UK:
Gurney & Jackson.
Wind, J. and Soesilo, B. K. (1978) Proposed
Halimun Nature Reserve management
plan
1979-1982
. Bogor, Indonesia: FAO.
Wolters, H. E. (1977) Die Vogelarten der
Erde. Hamburg and Berlin, Germany: Paul
Parey.
Wordpress (2011). [Information on regional
minimum wages, 2010, 2011]. URL: http://
allows.wordpress.com/2009/01/12/informasi-
upah-minimum-regional-umr. Accessed on
20 July 2011. (In Indonesian).
S. (BAS) VAN BALEN*
Basilornis Consults, Roompotstraat 44, 6826 EP, Arnhem, The Netherlands.
JAMES A. EATON
17 Keats Avenue, Littleover, Derby, DE23 4EE, UK.
S. van Balen et al. 18
FRANK E. RHEINDT
Harvard University, Center for Organismic and Evolutionary Biology, 26 Oxford Street,
Cambridge MA 02138, USA.
*Author for correspondence; e-mail: bvanbalen001@hotmail.com
Received 17 February 2011; revision accepted 29 July 2011
Biology and conservation of Short-tailed Green Magpie in Java 19
... Examples of such victims of unrecognized cyptic diversity include the Critically Endangered Javan Green Magpie (Cissa thalassina) that was once lumped with the non-threatened Bornean Green Magpie (C. jefferyi) (van Balen et al., 2013); the Critically Endangered Javan Leafbird (Chloropsis cochinchinensis) was previously considered a species with the widespread Blue-winged Leafbird (Chloropsis moluccensis) (BirdLife International, 2017); the Critically Endangered Javan Pied Starling (Gracupica jalla) was recognised as a species with its Least Concern northern sister taxon Asian Pied Starling (Gracupica contra) (BirdLife International, 2019). ...
... Critically Endangered species such as the Javan Green Magpie (Cissa thalassina) (van Balen et al., 2013) and the Aceh Bulbul (Pycnonotus bimaculatus) . ...
Article
Full-text available
Southeast Asian avifauna is under threat from both habitat loss and illegal poaching, yet the region’s rich biodiversity remains understudied. Here, we uncover cryptic species-level diversity in the Sunda Blue Robin (Myiomela diana), a songbird complex endemic to Javan (subspecies diana) and Sumatran (subspecies sumatrana) mountains. Taxonomic inquiry into these populations has previously been hampered by a lack of DNA material and the birds’ general scarcity, especially sumatrana which is only known from few localities. We demonstrate fundamental bioacoustic differences in courtship song paired with important distinctions in plumage saturation and tail length that combine to suggest species-level treatment for the two taxa. Treated separately, both taxa are independently threatened by illegal poaching and habitat loss, and demand conservation action. Our study highlights a case of underestimated avifaunal diversity that is in urgent need of revision in the face of imminent threats to species survival.
... Based on empirical data, in the last decades, some birds that are predominantly contested in the bird song competition and intensively hunted by village people have dramatically decreased of songbird populations; the cucak rowo/straw-headed bulbul (Pycnonotus zeylanicus) is a case in point . Therefore, in last several decades, it has been revealed that change or loss habitat and capturing wild birds for commercial purposes across culture in the world have been the principal causes of population decrease among many bird species (Bennet 2002;Suba et al. 2011;van Balen et al. 2011;Harris et al. 2015;Chng et al. 2015;Ayat and Tata 2015;Irawati et al. 2015;Iskandar 2014;Iskandar et al. 2016;Partasasmita et al. 2016;Dai and Hu 2017;Shepherd and Cassey 2017;Setioko 2019;Hakim et al. 2020). ...
... Therefore, if the hunting rate of rare or endangered species is higher than the natural rate of regeneration of these birds species, then, in the long run, these species will become extinct (Bennett and Robinson 2000). Indeed, based on the results of cross-studies culture in Indonesia and other countries shows that the factors of hunting and trade in bird species, in addition to habitat destruction or extinction, have been the main causes of the scarcity and even extinction of bird species in nature (Bennett and Robinson 2000;Bennett et al. 2002;van Balen et al. 2011;Fernandez-Ferreira et al. 2012;Chng et al. 2015;Harris et al. 2015;Irawati et al. 2016;Dai and Hu 2017;Shepherd and Cassey 2017;Setioko 2019;Hakim et al. 2020). ...
Article
Full-text available
Iskandar J, Iskandar BS, Mulyanto D, Alfian RL, Partasasmita R. 2020. Traditional ecological knowledge of the bird traders on bird species bird naming, and bird market chain: A case study in bird market Pasty Yogyakarta, Indonesia. Biodiversitas 21: 2586-2602. The bird-keeping in Indonesian society has been popular for a long time. Because the demand for birds has increased in an urban area, plenty of bird species are predominantly traded in urban bird markets. Bird market is a place for selling and buying various birds. The rise of bird trade in the bird markets in many regions of Indonesia has provided social and economic benefits for many people. But in addition to providing many benefits, the plentiful bird trade in bird markets that are not well managed is very worrying about the extinction of various bird species in rural ecosystems. This paper aimed to elucidate the Traditional Ecological Knowledge (TEK) of bird traders on bird species traded, bird naming and folk classification of bird species, and market chain system based on a case study in bird market of Pasty, Yogyakarta. The method used in this study was a qualitative method with the ethnoornithological approach. The results of the study showed that it was documented 106 bird species representing 40 families traded in the Pasty bird market. The common local names and folk bird classification are culturally based on bird vocalization, special colors, morphological characteristics, special habitats, involvement in bird song contests, flying racing competitions, selling prices, and wilderness. Most wild and semi-bird species are traded in the Pasty bird market are predominantly supplied from a rural ecosystem.
... Bioacoustic information, which is otherwise so indispensable in judging species limits in songbirds (e.g. van Balen et al. 2013), has been nearly impossible to analyse given these birds' renowned vocal variability even within populations or individuals. ...
Article
Unsustainable wildlife trade across South-East Asia has contributed significantly to the extinction threats faced by many songbirds. The Barusan Shama Copsychus (malabaricus) melanurus, a highly-prized songster from the West Sumatran Archipelago,is one of the most threatened taxa in Asia’s songbird trade crisis, yet its predicament is often overlooked because some taxonomists treat it as a mere subspecies of the widespread White-rumped Shama C. malabaricus. Here, we provide the first modern comprehensive assessment of the on-the-ground status of Barusan Shamas across all major islands of the West Sumatran Archipelago based on visual and bioacoustic surveys, mist-netting activity, as well as community interviews covering approximately the last five years. A lack of ornithological field records across many years as well as documented drops in local capture rates indicate that increasing poaching pressure and market value have likely driven the Barusan Shama to extinction in the wild on all islands except Siberut. Even on Siberut, we document a drastic population crash and estimate impending extinction in the wild within perhaps five years in the absence of considerable changes in human behaviour. The decline and presumed extermination of some Barusan Shama island populations was so precipitous that it became evident even within our five-year monitoring period. Although our field efforts and those of others must continue, this bird’s future now likely hinges on ex situ conservation efforts. The Barusan Shama occurs in four described subspecies, each endemic to its own island group, further complicating conservation efforts. Although the nominate subspecies melanurus remains relatively common in captivity on Nias and Mentawai, the other three subspecies are currently known from captive populations of a magnitude of about 100 for hypolizus, a handful for opisthochrus and zero for mirabilis, casting doubt on whether ex situ efforts can be initiated fast enough to assure the survival of individual subspecies.
... Our analysis revealed deep genomic and mitochondrial divergence as well as important phenotypic differences within some Southeast Asian babbler and bulbul species complexes and adds to previous research documenting a high incidence of cryptic diversity in tropical Southeast Asian forest and woodland birds (Garg et al., 2016;Lohman et al., 2010;Rheindt & Eaton, 2010;Van Balen, Eaton, & Rheindt, 2012). ...
Article
Quaternary climate oscillations are a well‐known driver of animal diversification, but their effects are most well studied in areas where glaciations lead to habitat fragmentation. In large areas of the planet, however, glaciations have had the opposite effect, but here their impacts are much less well understood. This is especially true in Southeast Asia, where cyclical changes in land distribution have generated enormous land expansions during glacial periods. In this study, we selected a panel of five songbird species complexes covering a range of ecological specificities to investigate the effects Quaternary land bridges have had on the connectivity of Southeast Asian forest biota. Specifically, we combined morphological and bioacoustic analysis with an arsenal of population‐genomic and modelling approaches applied to thousands of genome‐wide DNA markers across a total of hundreds of individuals. Our analyses show that species dependent on forest understorey exhibit deep differentiation between Borneo and western Sundaland, with no evidence of gene flow during the land bridges accompanying the last 1‐2 ice ages. In contrast, dispersive canopy species and habitat generalists have experienced more recent gene flow. Our results argue that there remains much cryptic species‐level diversity to be discovered in Southeast Asia even in well‐known animal groups such as birds, especially in non‐dispersive forest understorey inhabitants. We also demonstrate that Quaternary land bridges have not been equally suitable conduits of gene flow for all species complexes, and that life history is a major factor in predicting relative population divergence time across Quaternary climate fluctuations.
... Indeed, these problems have proven substantial enough to prevent most taxonomists from adopting it (Rheindt et al. 2011; but see e.g. Balen et al. 2013;Schuchmann et al. 2016). However, most of these problems do not concern the measurement approach, but the particular way the Tobias criterion implements it. ...
Article
Full-text available
After decades of debates about species concepts, there is broad agreement that species are evolving lineages. However, species classification is still in a state of disorder: different methods of delimitation lead to competing outcomes for the same organisms, and the groups recognised as species are of widely different kinds. This paper considers whether this problem can be resolved by developing a unitary scale for evolutionary independence. Such a scale would show clearly when groups are comparable and allow taxonomists to choose a conventional threshold of independence for species status. Existing measurement approaches to species delimitation are typically shot down by what I call the heterogeneity objection, according to which independently evolving groups are too heterogeneous to be captured by a single scale. I draw a parallel with the measurement of temperature to argue that this objection does not provide sufficient reasons to abandon the measurement approach, and that such an approach may even help to make the vague notion of evolutionary independence more precise.
... 2. The strongest line of evidence for species status is our vocal dataset. In many songbirds, vocalizations have been shown to be better indicators of taxonomy than plumage characters (Rheindt et al. 2008), and the use of vocalizations in passerine species delimitation has become routine (Alström and Ranft 2003), including in Indonesian birds (Rheindt and Hutchinson 2007;Van Balen et al. 2013;Ng et al. 2016;Gwee et al. 2019). Our analyses showed that the song of the Alor Myzomela is a slower, lower-pitched series of notes than that of the Wetar taxon ( Fig. 4; Table 2). ...
Article
Full-text available
We here describe a new species of Myzomela honeyeater from the Lesser Sunda island of Alor (southeast Indonesia). The new species is phylogenetically most closely related to Myzomela kuehni from the adjacent island of Wetar and most closely resembles that species in plumage. However, it differs in important morphological, bioacoustic and ecological characteristics. The discovery of a new bird species on Alor is of great biogeographic importance and elevates this island to the status of an Endemic Bird Area. The new Alor Myzomela is restricted to montane eucalypt woodland mostly above 900 m elevation and is currently known from few sites across the island. Based on its occurrence records and human population trends in the highlands of Alor Island, we recommend classification under the IUCN threat status endangered.
... In oscine songbirds, such as Cyornis flycatchers, juveniles are capable of learning acoustic motifs from adult conspecifics and from the external environment (Clayton, 1990;Beecher & Brenowitz, 2005), rendering their songs among the most vocally complex bioacoustic signals in nature. Nevertheless, the need for successful communication generates selective pressure to keep vocalizations sufficiently homogeneous within oscine species so as to render them excellent tools for species delimitation (van Balen et al., 2013;Cros & Rheindt, 2017;Prawiradilaga et al., 2017;Alström et al., 2018). To deal with the extensive bioacoustic flexibility of oscines, recordings containing heterospecific song structures were removed to ensure homologous comparisons among taxa. ...
Article
Full-text available
Despite the ongoing taxonomic revolution incorporating multiple species delimitation methods, knowledge gaps persist in the taxonomy of comparatively well-studied animal groups such as birds. Morphologically cryptic species risk slipping under the conservation radar, as they get mistakenly united with other species. Here, we employed six to 11 vocal parameters of each population to examine the species delimitation of nine Cyornis jungle-flycatcher species complexes distributed across Asia. We found moderate to strong vocal evidence for the taxonomic elevation of ten cryptic Cyornis species. Additionally, we conducted mitochondrial and genome-wide SNP analyses for two of the Cyornis complexes to examine the effectiveness of bioacoustics as a tool for avian species delineation and found congruent results between vocal and molecular data. Therefore, we propose a taxonomic reclassification of the complicated Cyornis species complexes and recommend routine application of bioacoustics in avian taxonomic classification.
... Even though several species have been described based on solely phenotypic characters (e.g., van Balen et al. 2011, Sangster et al. 2013, Eaton & Collar 2015, Sangster et al. 2016, a thorough molecular analysis of P. georgicus would provide useful insights. Such an analysis would provide further information on the status of the SIO and SAO populations and would also complement the preliminary results by Paterson et al. (2000). ...
Thesis
Full-text available
Procellariiformes diverse order of seabirds under considerable pressure from onshore and offshore threats. New Zealand hosts a large and diverse community of Procellariiformes, but many species are at risk of extinction. In this thesis, I aim to provide an overview of threats and conservation actions of New Zealand’s Procellariiformes in general, and an assessment of the remaining terrestrial threats to the South Georgian Diving Petrel (Pelecanoides georgicus; SGDP), a Nationally Critical Procellariiform species restricted to Codfish Island (Whenua Hou), post invasive species eradication efforts in particular. I reviewed 145 references and assessed 14 current threats and 13 conservation actions of New Zealand’s Procellariiformes (n = 48) in a meta-analysis. I then assessed the terrestrial threats to the SGDP by analysing the influence of five physical, three competition, and three plant variables on nest-site selection using an information theoretic approach. Furthermore, I assessed the impacts of interspecific interactions at 20 SGDP burrows using remote cameras. Finally, to address species limits within the SGDP complex, I measured phenotypic differences (10 biometric and eight plumage characters) in 80 live birds and 53 study skins, as conservation prioritisation relies on accurate taxonomic classification. The results from the meta-analysis revealed that New Zealand’s Procellariiformes are at risk from various threats (x̅ = 5.50 ± 0.34), but species also receive aid from several conservation actions (x̅ = 7.19 ± 0.33). Results from a logistic regression showed that smaller species are more threatened onshore than offshore. The majority of the conservation actions appear in place where needed. However, habitat management, native predator control and the mitigation of risks associated with environmental stochasticity may need improvement. Analysis of SGDP nest-site selection showed dependency on mobile, steep, seaward-facing foredunes. Invasive plant species, the presence of conspecifics, or the presence of other seabird species did not influence SGDP nest-site selection. Assessment of interspecific interactions at SGDP burrows showed seven species occurring at burrows, but only Common Diving Petrels (P. urinatrix; CDP) interfered with SGDP breeding success. Assessment of phenotypic differences within the SGDP revealed that the New Zealand SGDP population differs in five biometric and three plumage characters from all other populations and warrants species status based on a species delimitation test with quantitative criteria. I propose to name this Critically Endangered species Pelecanoides taylorii sp. nov. These findings indicate that P. taylorii is of considerable conservation concern and additional measures, even after successful eradication of invasive species, may be required to safeguard this species. Based on the habitat preference, stochastic events, such as storms and storm surges, appear a major threat to P. taylorii. The assessed interspecific interactions at nest-sites, indicate competition with CDPs to be a minor threat. I propose a translocation as a potential strategy to relieve the pressure on P. taylorii, but further monitoring and research is needed to enable the implementation of such a conservation strategy.
Article
Full-text available
Designating protected areas remains a core strategy in biodiversity conservation. Despite high endemism, montane forests across the island of Java are under-represented in Indonesia's protected area network. Here, we document the montane biodiversity of Gunung Slamet, an isolated volcano in Central Java, and provide evidence to support its increased protection. During September–December 2018, we surveyed multiple sites for birds, primates, terrestrial mammals, reptiles, amphibians and vegetation. Survey methods included transects, camera traps and targeted searches at six sites, at altitudes of 970–2,512 m. We used species distribution models for birds and mammals of conservation concern to identify priority areas for protection. We recorded 99 bird species (13 globally threatened), 15 mammals (five globally threatened) and 17 reptiles and amphibians (two endemic). Our species distribution models showed considerable cross-taxon congruence between important areas on Slamet's upper slopes, generally above 1,800 m. Particularly important were records of the endemic subspecies of the Endangered Javan laughingthrush Garrulax rufifrons slamatensis , not recorded in the wild since 1925, the Endangered Javan gibbon Hylobates moloch and Javan surili Presbytis comata , and the Vulnerable Javan lutung Trachypithecus auratus and Javan leopard Panthera pardus melas . Recent forest loss has been modest, at least 280 km ² of continuous forest remain above 800 m, and our surveys show that forest habitats are in good condition. However, the mountain is widely used by trappers and hunters. Given its importance for biodiversity conservation, we discuss different options for improving the protection status of Gunung Slamet, including designation as a National Park or Essential Ecosystem.
Article
Full-text available
The genus Pygocentrus contains three valid piranha species (P. cariba, P. nattereri and P. piraya) that are allopatric in tropical and subtropical freshwater environments of South America. This study uses acoustic features to differentiate the three species. Sounds were recorded in P. cariba, two populations of P. nattereri (red-and yellow-bellied) and P. piraya; providing sound description for the first time in P. cariba and P. piraya. Calls of P. cariba were distinct from all the other studied populations. Red-and yellow-bellied P. nattereri calls were different from each other but yellow-bellied P. nattereri calls were similar to those of P. piraya. These observations can be explained by considering that the studied specimens of yellow-bellied P. nattereri have been wrongly identified and are actually a sub-population of P. piraya. Morphological examinations and recent fish field recordings in the Araguari River strongly support our hypothesis. This study shows for the first time that sounds can be used to discover identification errors in the teleost taxa.
Article
Full-text available
This is the first thorough investigation into the very large and diverse trade in live wild animals for pets in Medan, Sumatra, Indonesia. Monthly surveys of the wildlife markets conducted between 1997 and 2001, supported by interviews with various stakeholders (harvesters, merchants and consumers), were used to produce a comprehensive inventory of the bird, mammal and reptile species found in the live animal trade in Medan, as well as information regarding harvest methods and consumer uses. A total of 300 species of birds from 54 families, 34 species of mammals from 15 families and 15 species of reptiles from 11 families were recorded during the five years of this study. Legislative analysis determined that a significant portion of the trade was illegal, violating Indonesian wildlife protection laws. It was also found that the bulk of the trade fell outside the scope of CITES1, either because it was of domestic origin and not destined for export, or because the species concerned were not listed under the Convention, or both. Much of the wildlife was harvested locally, especially from the nearby Gunung Leuser National Park, and the trade has likely had some adverse impacts on Indonesia’s biological diversity – although very little is known about the status of wild populations in Sumatra. This report documents the large volume of wild-caught specimens traded in the markets, and makes indirect conclusions concerning the impact on wild populations, with the understanding that further research is required to better quantify this impact. Improved protection under national legislation or by listing in the CITES Appendices is required for certain species. Furthermore, enforcement agencies should be encouraged to better enforce national legislation and CITES regulations. While legislation in Indonesia is relatively comprehensive, enforcement effort and efficiency remain insufficient to combat the current levels of wildlife trade. More comprehensive law enforcement at ports of entry (airports and seaports) and exit is crucial, and therefore capacity building is essential for enforcement personnel based at all entry and exit-points. Lack of species identification skills within the local enforcement agencies greatly restricts law enforcement efforts. Regular monitoring of the wildlife markets in Medan should continue so that further trends in the trade may be identified. Establishment of an efficient and accurate monitoring mechanism would facilitate management and law enforcement, leading to better compliance with national and international legislation, and by extension, greater conservation benefit.
Article
The present authors independently from one another studied oological material from Java. The results of their studies are combined in the present paper. Hellebrekers deals with three collections, held by the Rijksmuseum van Natuurlijke Historie at Leiden, brought together (a) by M. E. G. Bartels and his sons (4770 shells), (b) by J. G. Kooiman (280 shells), and (c) by H. J. V. Sody (175 shells). Of these collections those made by Bartels and Sody consist almost exclusively of eggs from West Java, while that made by Kooiman originates from East Java. Hoogerwerf gives details of 1020 shells of his own collection, almost all of which originate from West Java. These were obtained after the appearance in 1949 of a paper in which he published the colour descriptions and measurements of 5680 Javanese eggs which, however, were not weighed (Hoogerwerf, 1949). In the present paper the weights of 2200 of these previously discussed shells are published by Hoogerwerf. The remainder of the 1949 material (including the Bouma collection from Central Java) is in the Zoological Museum at Bogor, Indonesia, and therefore could not be weighed for the present study. In total, below are published the measurements of 6245 and the weights of 8240 shells. A large number of eggs of the families Phalacrocoracidae, Ardeidae, Ciconiidae, Threskiornithidae and Plataleidae of which Hoogerwerf gives details here, were not collected, but put back into the nests after being measured, as this was done also with part of the material reported by him in 1949. In Hoogerwerf's part it often happens that the number of measured shells is not in accordance with that of the weighed ones. This is caused by the fact that weights of previously examined shells — of which the measurements are not included in the present paper — are added; also the measurements