Journal of Threatened Taxa |
www.threatenedtaxa.org | 26 May 2021 | 13(6): 18532–18543
ISSN 0974-7907 (Online) | ISSN 0974-7893
(Print)
https://doi.org/10.11609/jott.7269.13.6.18532-18543
#7269 | Received 12 March 2021 | Final
received 27 April 2021 | Finally accepted 04 May 2021
Legal or unenforceable?
Violations of trade regulations and the case of the Philippine Sailfin Lizard Hydrosaurus pustulatus (Reptilia: Squamata: Agamidae)
Sarah Heinrich 1, Adam
Toomes 2 &
Jordi Janssen 3
1,2 Invasion Science and Wildlife
Ecology Lab, School of Biological Sciences, The University of Adelaide, SA
5005, Australia.
1,3 Monitor Conservation Research
Society (Monitor), Big Lake Ranch, B.C., V0L 1G0, Canada.
1 sarah.heinrich@adelaide.edu.au
(corresponding author), 2 adam.toomes@adelaide.edu.au, 3 jordi.janssen@mcrsociety.org
Editor: Raju Vyas, Vadodara, Gujarat,
India. Date of publication: 26 May 2021
(online & print)
Citation: Heinrich, S., A. Toomes & J. Janssen (2021). Legal or unenforceable?
Violations of trade regulations and the case of the Philippine Sailfin Lizard Hydrosaurus pustulatus
(Reptilia: Squamata: Agamidae).
Journal of Threatened Taxa 13(6): 18532–18543. https://doi.org/10.11609/jott.7269.13.6.18532-18543
Copyright: © Heinrich et al. 2021. Creative Commons Attribution
4.0 International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by providing adequate credit to the
author(s) and the source of publication.
Funding: WWF-Netherlands.
Competing interests: The authors
declare no competing interests.
Author details: Sarah Heinrich is an independent scientist and
visiting research fellow at the University of Adelaide. Adam Toomes is a PhD student at the University of
Adelaide. Jordi Janssen is a programme
officer at the Monitor Conservation Research Society.
Author contributions: SH designed the study,
collected, curated and analysed the data and wrote
the manuscript. AT contributed to the
data collection and analysis. AT and JJ contributed critically to the
development of the drafts and writing of the manuscript and gave final approval
for publication.
Acknowledgements: We would like to thank
WWF-Netherlands for their generous support.
We are grateful to Oliver C. Stringham (the University of Adelaide) who
wrote the code for the automated data collection of online trade data. Chris R. Shepherd (Monitor) is thanked for
providing useful feedback on an earlier version of the manuscript. Jordi Janssen would like to thank a donor who
wishes to remain anonymous for supporting Monitor’s work on live reptile
trade. Adam Toomes’
PhD scholarship is funded by the Centre for Invasive Species Solutions Project
ID PO1-I-002 and the FJ Sandoz Scholarship.
Abstract: The Philippine Sailfin Lizard (Agamidae: Hydrosaurus pustulatus) is a nationally protected Philippine
endemic species. It is threatened by
habitat destruction, pollution and overexploitation for the domestic pet trade,
yet less is known about the international component of the trade. Here we investigate the international trade
in Hydrosaurus spp. (H. weberi,
H. amboinensis, and H. pustulatus)
with an emphasis on H. pustulatus. We analysed international seizures combined
with international online sales and trade data for the United States of America
(USA). The export of H. pustulatus from the Philippines has been prohibited
since 1991, except under special circumstances, yet they continue to be traded
internationally, and we found evidence for trade in Asia, Europe, and North
America. Most of these animals, however,
were declared to be captive-bred. While
imports to and exports from the US consisted mostly of other species of Hydrosaurus, H. pustulatus
was by far the most coveted species online, with prices significantly higher
for H. pustulatus than any of the other
species. While not many seizures have
occurred outside the Philippines, even wild-caught individuals were found to be
‘legally’ imported to the USA – in apparent violation of the Lacey Act. We recommend H. pustulatus
to be listed in CITES Appendix III, in order for countries other than the USA
to have a legal basis to seize wild-caught animals trafficked from the
Philippines and to monitor trade in captive-bred specimens. Further, we suggest the use of automated
cross-referencing between imported species and the national protection status
of the species’ native range states to ensure that legislation violations are
detected at the point of import.
Keywords: CITES, conservation, Lacey Act,
LEMIS, reptiles, wildlife trade.
Abbreviations: CITES—The
Convention on International Trade in Endangered Species of Wild Fauna and Flora
| DAO—Department of Environment and Natural Resources Administrative Order |
DENR—Department of Environment and Natural Resources | LEMIS—Law Enforcement
Management Information System | USA—United States of America | USD—US Dollars |
Wildlife Act—Wildlife Resources Conservation and Protection Act of 2001
(Republic Act No. 9147).
Unsustainable wildlife trade,
both illegal and legal, threatens an increasing number of species globally (Rosser & Mainka 2002;
Marshall et al. 2020). To ensure that international
trade in wildlife does not threaten their survival, the Convention on
International Trade in Endangered Species of Wild Fauna and Flora (CITES)
entered into force in 1975. Currently,
more than 38,000 taxa that are threatened by international trade are listed in
one of the three Appendices of CITES, which regulate the trade in these species
to varying levels; however, many species that are traded internationally are
not included in the CITES Appendices, often because international trade data
and/or other assessments are lacking for these species (Purcell et al. 2014; Vincent et al. 2014; Janssen
& Shepherd 2018; Janssen & Leupen 2019; Jensen et al. 2019).
The pet trade in particular has increased substantially in recent years
and reptiles are among the most heavily exploited taxa for this purpose (Herrel & van der Meijden 2014; Auliya et al. 2016;
Jensen et al. 2019; Marshall et al. 2020).
While not the largest in terms of volume, more species are traded for
the international trade for pets than for any other purpose (Janssen: in press).
Yet, as of November 2019, only ~954 reptile species are listed in the
Appendices of CITES (https://cites.org/eng/disc/species.php)
– approximately 8% of all currently recognised reptile species (Uetz et al. 2020).
Non-CITES species can usually be
traded without international restrictions that would ensure the sustainability
of the species’ exploitation, and only few national legislations protect
non-native, non-CITES species in trade (Vinke & Vinke 2015; Janssen & Leupen
2019; Jensen et al. 2019). This is
especially relevant when it comes to nationally protected species that are
found in international trade. Many of
these, such as the Borneo Earless Monitor Lanthanotus
borneensis prior to its Appendix II listing in
2017 (Janssen & Krishnasamy 2018), are illegally
extracted from the wild in their range states and exported to international
destinations, where a lack of or inadequate legislation impedes efforts to
counter this trade (Altherr
2014; Auliya et al. 2016; Altherr
& Lameter 2020).
Once these animals have entered a consumer country, they often continue
to be traded ‘legally’ (Vinke
& Vinke 2015; Heinrich et al. 2021).
Hydrosaurus spp. represent the largest
members of the Agamidae family and can grow over a
meter in length (Denzer et
al. 2020). These oviparous, omnivorous, semi-aquatic
lizards are restricted to riparian vegetation in coastal regions of different
islands in Indonesia, New Guinea, and the Philippines (Ledesma et al. 2009; Denzer et
al. 2020). Hydrosaurus
spp. are known to be threatened by habitat loss and pollution, local
subsistence hunting, as well as overexploitation for the pet trade, for which
the hatchlings and subadults are especially targeted (Ledesma et al. 2009; Siler et al. 2014; Department of
Environment and Natural Resources 2020).
One nationally protected species negatively affected by trade is the
endemic Philippine Sailfin Lizard Hydrosaurus
pustulatus (Image 1). While H. pustulatus
is classified as ‘Vulnerable’ on the IUCN Red List of Threatened Species (Ledesma et al. 2009), the remaining Hydrosaurus species have not been assessed to
date.
It has been suggested that there
are two species occurring in the Philippines, H. pustulatus
in the north and H. amboinensis in the south,
but that their exact distribution is unclear due to identification issues (Ledesma et al. 2009); however, there is a general
uncertainty regarding Hydrosaurus taxonomy and
species distribution, with more recent studies suggesting that only H. pustulatus occurs in the Philippines (Siler et al. 2014; Denzer et
al. 2020). Further, Siler et al.
(2014) suggested
that there are four species of Hydrosaurus
based on genetical analyses, but noted that further research is required. Denzer et al. (2020) conclude that there are
currently five species within the genus Hydrosaurus,
mainly based on morphological features.
Due to the unresolved nature of the genus taxonomy, there is a high likelihood
of mislabelling during trade, deliberately or otherwise. Siler et al.
(2014) also
describe at least six genetically distinct clades of H. pustulatus restricted to different Philippine
islands and note that the sailfin lizards found in the illegal domestic trade
(at least in Manila) originate from a single clade of H. pustulatus sourced from the Bicol Faunal Region,
particularly the island of Luzon.
The Philippines has strong
wildlife legislation in place, which pertaining to terrestrial wildlife, mainly
consists of the Wildlife Resources Conservation and Protection Act of 2001
(Republic Act No. 9147, hereafter also referred to as the ‘Wildlife Act’) and
its implementing Rules and Regulations.
Pursuant to Section 5 and 22 of the Wildlife Act, the preliminary ‘List
of Threatened Wildlife’ was established in 2004 by the Department of
Environment and Natural Resources (DENR) Administrative Order (DAO) No.
2004-15, which was last updated in 2019 by DAO No. 2019-09. Since 2004, H. pustulatus
is classified as ‘Other Threatened Species’ and it is illegal to collect or
trade the species (including exportation), except under special circumstances
(such as an exemption for captive-bred animals) which need to be accompanied by
a permit issued by DENR. Before 2004, H.
pustulatus was classified as a ‘Rare’ species
from 1991 according to DAO 91-48, equally prohibiting its collection and trade
(including export) unless permitted by DENR, as is the case today. Since 1991 there have only been three legal
exports of H. pustulatus from the Philippines,
all of which were captive-bred animals, and no facilities currently have a
permit to export H. pustulatus for commercial
purposes in the Philippines (DENR Biodiversity Management Bureau, in litt., April 2021).
The Philippine Sailfin Lizard is
known to be exploited for the domestic trade (Sy 2018; Sy 2021), yet less is known about its
availability on the international market.
They have been observed in low quantities, e.g., in mainland China (Yunrui et al. 2020) and Taiwan (Shiau et al. 2006), and anecdotal evidence suggests
that they were more common in the United States of America (USA) and Europe in
the 1970s and 80s, until the Philippines restricted the species’ export in
1991. Grey literature documenting the
husbandry and captive breeding of this species dates back to the 1970s (e.g., Gonzales 1974) with scattered reports on husbandry and breeding
results over time (Krasula
1988; Gábriš 2003; Wirth & Riedel 2011; Fischer
2020a,b). Yet, despite a history of being kept and bred
in captivity, its large size and resulting husbandry requirements, in
combination with export restrictions, have likely contributed to them not being
widely available on the international market to date.
Due to the relatively small captive
population and thus limited available offspring, H. pustulatus
is potentially at risk of unsustainable harvesting if emergent demand
exceeds the availability of animals.
Moreover, the unresolved taxonomy presents an opportunity for
laundering, as H. pustulatus may be labelled
as other Hydrosaurus species that are similar
in appearance yet have fewer trade regulations.
Here we investigate and characterise the scale of the international
trade in H. pustulatus and other Hydrosaurus species, with specific focus on illegal
trade in wild-caught specimens and the conservation implications.
Seizure data were requested from
the Philippines Department of Environment and Natural Resources; however, no
response was received. We thus collated
seizure data on sailfin lizards (Hydrosaurus
spp.) from open-source media reports, such as the Robin des Bois On the Trail bulletins (https://robindesbois.org;
containing seizure incidents available from 2013–2020), ad hoc online searches,
and grey literature (e.g., Sy 2021). For two incidents where no
quantity was recorded, we assumed the incidents had to involve at least one
animal, noting that the true number of animals involved may have been higher.
Data for the USA from 2000–2018
were obtained from the Law Enforcement Management Information System (LEMIS)
database through a Freedom of Information Request. LEMIS Hydrosaurus
trade data consisted almost exclusively of live animals. As we were mostly interested in the pet
trade, we excluded the 49 ‘scientific or museum specimens’ from seven trade
records, as well as the 525 mollusc or turtle shell products from one trade
record (which we also assumed must have been misclassified by the Fish and
Wildlife Service).
We collated online trade data
from English language and Japanese websites.
Japanese websites were chosen because of anecdotal reports, it being
known as a popular destination for exotic pets (Vall-Llosera & Su 2018; Wakao
et al. 2018; McMillan et al. 2020), as well as Japan being reported as a destination in
the previously recorded seizure incidents.
Following the framework of Stringham et al.
(2020) we obtained
human research ethics committee approval from the University of Adelaide
(Australia) to use automated data mining and searched a total of eight international
English language and eight Japanese websites, using the keywords ‘sailfin’ and
‘Hydrosaurus’, as well as in October 2020. For ethical reasons we keep the identities of
the websites anonymous (see also Stringham et al.
2020), however,
they are international classifieds that receive a high frequency of daily
trade. We manually checked each entry to
confirm the animals in the listings were in fact referring to sailfin lizards
of the genus Hydrosaurus, as ‘sailfin’ also
led to results for other species (e.g., chameleons, geckos, Australian water
dragons). During the data curation
process we recorded characteristics from the listing text description,
including but not limited to: i) the species (H. pustulatus, H. amboinensis,
or H. weberi); ii) price; iii) source
(captive-bred or wild-caught); and iv) life stage (juvenile, subadult, or
adult).
If the species was not
specifically mentioned in the listing text, we classified it as Hydrosaurus spp.
Due to the uncertain and changing taxonomy of the genus Hydrosaurus, it is possible that the advertised H.
amboinensis and H. weberi
may be individuals that are now recognised as H. celebensis
or H. microlophus, therefore we regard the
observed H. amboinensis and H. weberi as sensu lato. The price per
animal was recorded as described in the listing text and later transformed to
‘price per animal’ in American Dollars (USD).
If the total price was given for all advertised animals in the listing,
price was converted to price per individual.
If the price was given in a currency other than USD, the price per
animal was converted to USD in December 2020 (www.xe.com). We also recorded whether the animal for sale
was a hybrid or morph (i.e., colour variety), all of which were later
classified as ‘Hydrosaurus spp.’ and assumed
to be captive-bred, even if the source was not stated specifically in the
listing text. ‘CB’ was assumed to mean
captive-bred. ‘Captive born’ or ‘Farm
bred’ animals were also classified as captive-bred. Animals were only classified as ‘wild-caught’
if this was specifically stated in the listing text. If not otherwise stated whether the animals
were wild-caught or captive-bred, all other listings were classified as ‘unknown’
regarding the source of the animals. The
life stage of the animals was recorded as reported in the listing text, being
either ‘juvenile’, ‘subadult’, or ‘adult’.
‘Babies’ were classified as juveniles.
In n= 32 listings the size of the animals was reported in conjunction
with the life stage and following the data distribution of these listings we
later added the life stage according to the size of the animal, for instances
where only the size, but not the life stage, was reported in the listing text
(n= 34). For this we assumed that the
total length of the animals was reported in all instances and if animals were
below 45cm they were classified as juveniles, between 46 and 85 cm as
subadults, and above 85cm as adults. The
quantity of the animals per listings were recorded from the listing text
description. If not stated otherwise,
each listing was assumed to include at least one animal. If not stated otherwise and the listing text
indicated that ‘sailfins’ (i.e., more than one animal) were involved, we
assigned two animals to the listing, noting that the true number of available
animals per listing may have been higher.
If a ‘clutch’ of animals was advertised we assumed that seven animals
would be involved (Meiri et
al. 2020).
Median prices and data
distribution were displayed using the ‘ggplot2’ package (Wickham 2016). Generalised
linear models (GLMs) were used to test for effects of species, source and life
stage on market price. Advertisements of people looking to buy animals were
excluded from the price analysis.
Candidate models were selected based on the lowest Akaike’s Information
Criterion (ΔAIC > 5). New explanatory
variables, including interactive effects, were added to models in a stepwise
fashion if the inclusion of such variables sufficiently reduced the AIC. We conducted pairwise comparisons between
variable levels with the ‘emmeans’ package (Lenth et al. 2020).
Wald χ2 tests for independence were used to test for
differences in the quantity of traded animals per species recorded in the LEMIS
data, as well as between the quantity of advertised animals per species in
online listings. We used
contingency-type frequency tests to assess the independence of categorical
variables, using the mosaic function of the ‘vcd’
package (Meyer et al. 2017).
All data were curated and analysed in the R software environment for
statistical computing, version 4.0.1 (R Core Team
2020).
We found 15 seizure incidents
involving at least 233 sailfin lizards since 2010 from four countries (Table
1). In five incidents, involving 120
animals, the species was confirmed as H. pustulatus. In another nine incidents, involving at least
109 animals, the seizures occurred in the Philippines and the species was very
likely also H. pustulatus, although this was
not specifically mentioned. Only three
of the seizures occurred in countries outside the Philippines, namely
Indonesia, India, and Hong Kong (Table 1).
Reported destinations included Japan, Taiwan, and Sweden.
From 2000 to 2018 there were 421
trade records involving 12,479 live sailfin lizards. The majority of these consisted of animals of
the species H. weberi (Figure 1). During this timeframe, there were only four
imports into the USA involving 117 live H. pustulatus,
and 15 exports involving 70 H. pustulatus,
which was thereby the least traded of the three recorded species (Figure 1).
Hydrosaurus weberi was more likely to be declared
wild-caught and less likely to be captive-bred; whereas H. amboinensis and H. pustulatus
were more likely to be captive-bred and, in the case of H. amboinensis, less likely to be wild-caught (n= 421, χ2=
62.54, degrees of freedom df= 3, p <0.001; Figure
2). There were only seven shipments (one
import, seven exports) involving a total of 123 wild-caught Philippine Sailfin
Lizards. Only two of these shipments
(involving five animals) originated in the Philippines, while the remaining
five supposedly originated in Taiwan (one incident, 76 animals) and Indonesia
(four incidents, 42 animals).
We recorded a total of 369
listings involving at least 811 animals of the genus Hydrosaurus
on six of the eight English and two of the eight Japanese language
websites. Hydrosaurus
pustulatus was by far the most popular species
online with 141 listings involving at least 418 animals. It was followed by unidentified Hydrosaurus spp. (106 listings/187 animals), H. weberi (75/138), and H. amboinensis
(47/68). Of all listings, 281 (76%)
were advertising sailfin lizards for sale, while the remaining 88 listings
concerned people looking to buy sailfin lizards. Of the listings where people were searching
for sailfin lizards, 49 (56%) were looking for H. pustulatus
specifically. Most listings were
recorded from people in the USA with 295 listings (80%), followed by listings
from Japan (18 listings), the United Kingdom (UK; four), Portugal (three),
Ukraine (two), Spain (one), and Canada (one).
The country of the trader could not be identified in 45 listings.
Our selected candidate GLM
included the effects of price, life stage and source, as well as interactions
between levels of all three variables. The price per animal for H. pustulatus was significantly higher compared to H. amboinensis for captive juveniles (305.38 ± 106.1; p=
0.0209), yet lower for adults (-1169.37 ± 139.5; p <0.0001). Hydrosaurus pustulatus
were significantly higher in price than H. weberi
regardless of life stage (see Supplementary Data 1 for pairwise
comparisons). The median price per
animal for H. pustulatus (700 USD) was
significantly higher compared to H. amboinensis
(Estimate= -275.52, SE= 70.22, p < 0.001), H. weberi
(Estimate= -527.85, SE= 61.59, p <0.001), or unidentified Hydrosaurus spp. (Estimate= -347.48, SE=
57.5, p <0.001; Figure 3). Overall,
prices were lowest for H. weberi (median= 140
USD), but H. amboinensis (median= 183 USD) had
a few notable outliers, including the maximum price of any recorded listing of
2,500 USD for a single captive-bred adult animal (Figure 3). Adult H. pustulatus
were significantly less valuable than juveniles (-708.18 ± 266; p= 0.0458) if
they were wild-caught and were significantly more valuable than juveniles
(309.24 ± 107.3; p= 0.0205) and sub-adults (459.4 ± 124.2; p= 0.0012) if they
were captive-bred (Figure 4).
Hydrosaurus weberi and H. amboinensis
were more likely to be of wild-caught origin in online trade, and, in the case
of H. amboinensis, less likely to be
captive-bred (n= 369, χ2= 45.1, df= 6, p
<0.001; Figure 5). The opposite was
true for H. pustulatus in trade, which were
more likely to be captive-bred, and less likely to be of either wild or unknown
origin (Figure 5).
Of all listings, 13% noted
difficulties in keeping sailfins and reported either physical injuries of the
animals, such as nose rubbing, missing or damaged tails and digits, or
behavioural problems, such as skittishness, aggressiveness and/or fear towards
the owner or conspecifics, head bumping and/or deliberate running into cage
walls (noting that most advertisements did not include detailed descriptions of
the animals or reasons for selling).
Private owners also reported an inability to provide enough space, time,
and/or appropriate conditions for the animals as a reason for selling the
sailfins, while breeders often remarked on the special requirements that
sailfins need. For the 13% of listings
that did mention difficulties in keeping sailfins, most of these were in regard
to unidentified Hydrosaurus spp. (23 listings
/ 22% of all unidentified Hydrosaurus spp.
listings), and relatively equally distributed between H. pustulatus (14 listings/10% of all H. pustulatus listings), H. weberi
(8/11%), and H. amboinensis (4/9%). The proportion involving wild-caught animals
(23% of all listings involving wild-caught animals were noted having
difficulties in keeping the animals), however, was greater than for
captive-bred animals (11%) or animals of unknown origin (14%).
Our results demonstrate that
sailfin lizards of the genus Hydrosaurus are
coveted pets on the international market, and H. pustulatus
in particular appears to be the most popular of the Hydrosaurus
species, as shown with the online trade data.
It is possible, however, that idiosyncrasies exist between Hydrosaurus trade dynamics of online versus ‘brick
and mortar’ pet shops (e.g., Siriwat & Nijman 2020).
The USA featured most prominently in the international sailfin trade,
and while this could be due to our sampling method of collating online trade
data predominantly from English language websites, European countries were
comparatively less represented despite English-language websites being commonly
used to trade reptiles. Seizure data
revealed, however, that Sweden was one of the intended destinations for a
shipment of live H. pustulatus. Japan, a known destination country for a
variety of exotic pet species (Vall-Llosera
& Su 2018; Wakao et al. 2018; McMillan et al.
2020), was another
destination in seizure incidents, as well as Taiwan. Given that seizure data is subject to biases
due to imperfect detection (Symes et
al. 2018), illegal
trade is likely occurring at greater rates and across a greater diversity of
European and Asian countries than is currently recorded. In terms of the online advertisements, it
should be noted that more data may have been acquired using search terms from a
greater diversity of languages (see also Stringham et al.
2020).
LEMIS data revealed that the
majority of imports to and exports from the USA consisted of animals of the
species H. weberi and H. amboinensis in the last ~20 years (noting that due to
the uncertain taxonomy, species misidentifications are a genuine possibility
and individuals that were recorded as these species are also likely to include
the currently recognised species H. microlophus
and H. celebensis (Denzer et al. 2020)). In the same timeframe, only four imports
involving 117 live animals and 15 exports involving 70 live animals of H. pustulatus were recorded. Yet, H. pustulatus
is the most traded species in online marketplaces, 80% of which were recorded
on the American market, indicating that either the traded animals are bred in
captivity in the USA predominantly from stock imported prior to 1991,
captive-bred elsewhere and imported to the USA predominantly after 2018, or
that there continues to be an influx of illegal H. pustulatus
into the USA. If H. pustulatus trade is being supplied, or partly supplied,
by the illegal trade, wild-caught individuals are likely to be falsely declared
as captive-bred. Alternatively,
individuals bred in other nations may be imported without declaration, however
this is less likely, as there are no national or international regulations that
prevent legal captive-bred importations.
No online advertisements detected
in our study mention H. pustulatus to be of
wild-caught origin and H. pustulatus is
significantly more likely to be captive-bred, even compared to unknown
origins. Whether this is due to people
being aware of the illegality of their (wild-caught) pets, and fraudulently
declaring them as captive-bred, or because export restrictions from the
Philippines resulted in a captive population primarily consisting of
captive-bred animals, is unclear. We recognise
that there are genuine captive breeding efforts from specialised enthusiasts,
however, grown H. pustulatus are large animals
and can provide challenges to keep and breed in captivity when considering
husbandry requirements. Further, with
continuing demand and the comparatively high prices that can be obtained for H. pustulatus, the possibility remains that wild-caught
animals are illegally imported to the USA and elsewhere. As confirmed by the Philippine’s Biodiversity
Management Bureau, there have only been three legal exports of captive-bred
animals since 1991, and at the moment, no facilities in the Philippines have a
permit to export H. pustulatus for commercial
purposes.
It is clear that H. pustulatus is being traded internationally, and given the
high prices that can be attained with these animals and the associated high
commercial incentive to obtain and trade this species, this would suggest that
illegal trade is likely to occur. There
do not appear, however, to be many seizures of H. pustulatus,
which could be due to the fact that internationally, very few countries have a
legal framework to intercept nationally protected animals that were illegally
sourced from their origin country (Altherr 2014; Vinke & Vinke 2015). Therefore, in the case of H. pustulatus, a lack of international seizures does not
necessarily mean that there is no illegal trade, but rather that there is no
legal basis to confiscate the species once it has been smuggled out of its
origin country (see also Vinke & Vinke 2015).
This is often the case for nationally protected species that are illegal
to be exported, and exceptions usually involve CITES-listed species, countries
with legislation similar to the Lacey Act in the USA, or additional protections
such as the regulation of certain non-CITES species in the European Union
(Council Regulation (EC) No 338/97). Hydrosaurus pustulatus
is threatened domestically and largely unprotected internationally; therefore,
to address these issues, we recommend that H. pustulatus
be listed in CITES Appendix III by the Government of the Philippines.
The genus Hydrosaurus
was once proposed to be listed in CITES Appendix I at the first Conference of
the Parties in 1976 (Proposal 470); however, the proposal was rejected and no Hydrosaurus species was ever listed in any of the
CITES Appendices. Hydrosaurus
pustulatus is a nationally protected threatened
species that is evidently found in international trade, thereby fulfilling the
most important criteria for a CITES Appendix III listing (Res. Conf. 9.25 (Rev.
CoP18)). A listing of this species in
Appendix III may therefore assist in protecting wild populations in the
Philippines. For the right candidate
species, an Appendix III listing can have multiple benefits, including an
ability to monitor legal international trade (which in the case of H. pustulatus should essentially only occur in
captive-bred animals if they are traded commercially) and a legal basis
internationally to confiscate illegal specimens that are detected in
trade. Moreover, Appendix III listings have
the potential to curtail trade without rapidly increasing the perceived value
of a traded species, as is known to occasionally happen with Appendix I
listings (e.g., Janssen & Krishnasamy 2018).
The merits of a species- versus
genus-level listing should be considered carefully. Due to the unresolved taxonomy and similar
looking species with lower levels of protection, there is strong potential that
a species-level Appendix III listing may stimulate laundering via deliberate
mislabelling. A genus-level Appendix III
listing would reduce the likelihood of laundering, yet the impacts on trade of
potentially less threatened sailfin species should be weighed against the need
to protect H. pustulatus. Given the changing taxonomy of the genus, the
newly recognised Hydrosaurus species may need
to be re-assessed in terms of their conservation status, as they may be more
threatened than previously assumed.
Beyond CITES, individual nations
benefit from legislation that prevents the import of non-native wildlife if
they were illegally exported or harvested in their native range states. A well-known example of this is the Lacey
Act; under the Lacey Act, the import, export, sale, acquisition, or purchase of
wildlife taken, possessed, transported, or sold in violation of any USA or
foreign law is prohibited. Our study,
however, shows 123 wild-caught H. pustulatus
that were approved for import or export at some point into the USA despite
being in violation of the Lacey Act.
Only two of these shipments (one in 2013 and one in 2017 involving a
total of five animals) originated in the Philippines, while the remaining five
shipments supposedly originated in Taiwan (one incident, 76 animals in 2009)
and Indonesia (four incidents, 42 animals between 2003 and 2006). All shipments except the one from Taiwan were
exports from the USA, however, it remains uncertain how they were supposed to
be legally imported to the USA beforehand.
The only possibility is that these animals were imported prior to the
export restrictions from the Philippines in 1991, however, this seems
unlikely. Further, the Philippine
Sailfin Lizard does not occur in Indonesia nor Taiwan and all of these
shipments should have been seized; however, the only shipment of live Hydrosaurus spp. that was ever refused in the USA
concerned a single shipment of two H. amboinensis
that originated in Indonesia and were about to be exported to Canada. It is noteworthy that both Indonesia and
Taiwan were also found to be involved in illegal trade of H. pustulatus, as evidenced with the international seizure
data.
The approved importation of
illegally acquired wildlife, even in countries that do have a legal framework
to prevent such incidents, is not restricted to Philippine Sailfin
Lizards. Other studies have found
similar inconsistencies and violations of the Lacey Act (Altherr 2014; Auliya et al. 2016; Janssen & Leupen
2019; Janssen & Gomez 2021). Clearly, further measures need
to be taken to ensure that this valuable legislation is used effectively. We therefore propose the establishment of a
database where law enforcement officials and other interested parties can check
whether a non-CITES species is protected in its origin country/countries, and
whether wild-caught individuals are allowed to be exported. This database could be automatically cross
referenced against shipment information, including species, location of import
and captive/wild status, in order to rapidly detect violations of the Lacey Act
or other relevant legislation elsewhere.
While resources are inevitably required to establish such a database,
the long-term benefits to enforcement efficacy are likely to be
substantial. In the first instance, this
database could include only nationally protected, endemic, non-CITES species,
and subject to funding and resources, could be expanded to include other
nationally protected native non-CITES species at a later stage, as well as
further information on life history traits, and the ability to breed the
species in captivity. Such a database
could also be of value for the pet-keeping community to help in the decision
process of whether to purchase an animal.
Overall, these recommendations have the potential to curtail the trade
in wild-caught H. pustulatus, as well as other
threatened nationally protected species with international trade demand.
Table 1. International seizures
of sailfin lizards from January 2010 – February 2021.
|
Seizure date |
Species |
Seizure location |
Origin country |
Transit country |
Destination country |
Quantity seized1 |
|
18.ii.2021 |
Hydrosaurus spp. |
Philippines |
|
|
Taiwan |
15 |
|
05.vi.2020 |
H. pustulatus |
Philippines |
Philippines |
|
|
18 |
|
04.vi.2020 |
H. pustulatus |
Indonesia |
Philippines |
|
|
85 |
|
10.x.2019 |
Hydrosaurus spp. |
India |
|
Malaysia |
|
4 |
|
iii.2018 |
Hydrosaurus spp. |
Philippines |
|
|
Japan |
- |
|
26.x.2017 |
Hydrosaurus spp. |
Philippines |
|
|
Sweden |
10 |
|
28.i.2016 |
H. pustulatus |
Philippines |
|
|
Japan |
8 |
|
05.vi.2014 |
H. pustulatus |
Philippines |
|
|
|
4 |
|
viii.2013 |
Hydrosaurus spp. |
Philippines |
|
|
|
- |
|
08.ii.2012 |
H. pustulatus |
Hong Kong |
Philippines |
|
|
5 |
|
16.vii.2011 |
Hydrosaurus spp. |
Philippines |
|
|
|
3 |
|
02.vii.2011 |
Hydrosaurus spp. |
Philippines |
|
|
|
4 |
|
22.vi.2011 |
Hydrosaurus spp. |
Philippines |
|
|
|
1 |
|
19.vi.2010 |
Hydrosaurus spp. |
Philippines |
|
|
|
37 |
|
15.iii.2010 |
Hydrosaurus spp. |
Philippines |
|
|
|
37 |
1 Where the exact quantity was not
provided, we assumed the incident involved at least one animal, noting that the
true number of animals may have been higher.
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Supplementary
Data 1. Pairwise comparisons of the GLM output of the market price for all
combinations of sailfin lizard species (H. amboinensis,
H. pustulatus, H. weberi,
Hydrosaurus spp.), source (captive-bred,
wild-caught, unknown), and life stage (juvenile, subadult, adult, unknown).
|
Species = H. amboinensis, Source = Captive |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
1783.99 |
132.9 |
13.428 |
<.0001 |
|
adult - subadult |
1702.06 |
176.1 |
9.665 |
<.0001 |
|
adult - Unknown |
1843.17 |
148.9 |
12.377 |
<.0001 |
|
juvenile - subadult |
-81.93 |
135.8 |
-0.603 |
0.931 |
|
juvenile - Unknown |
59.18 |
108.5 |
0.546 |
0.9477 |
|
subadult - Unknown |
141.11 |
148.2 |
0.952 |
0.7765 |
|
Species = H. pustulatus, Source = Captive |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
309.24 |
107.3 |
2.883 |
0.0205 |
|
adult - subadult |
459.4 |
124.2 |
3.698 |
0.0012 |
|
adult - Unknown |
455.25 |
107.1 |
4.25 |
0.0001 |
|
juvenile - subadult |
150.16 |
105 |
1.43 |
0.4804 |
|
juvenile - Unknown |
146.01 |
79.3 |
1.841 |
0.2542 |
|
subadult - Unknown |
-4.15 |
105.4 |
-0.039 |
1 |
|
Species = H. weberi, Source = Captive |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
223.56 |
213.6 |
1.047 |
0.7219 |
|
adult - subadult |
169.9 |
226.7 |
0.75 |
0.8769 |
|
adult - Unknown |
298.17 |
220.2 |
1.354 |
0.5285 |
|
juvenile - subadult |
-53.67 |
110.5 |
-0.486 |
0.9623 |
|
juvenile - Unknown |
74.61 |
100.2 |
0.745 |
0.8789 |
|
subadult - Unknown |
128.27 |
129 |
0.994 |
0.7527 |
|
Species = Hydrosaurus
spp., Source = Captive |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
518.8 |
77.4 |
6.706 |
<.0001 |
|
adult - subadult |
444.56 |
99.8 |
4.453 |
<.0001 |
|
adult - Unknown |
599.18 |
85.9 |
6.979 |
<.0001 |
|
juvenile - subadult |
-74.24 |
87.7 |
-0.847 |
0.832 |
|
juvenile - Unknown |
80.37 |
71.8 |
1.12 |
0.6772 |
|
subadult - Unknown |
154.62 |
95 |
1.627 |
0.3631 |
|
Species = H. amboinensis, Source = Unknown |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
1587.73 |
137.6 |
11.54 |
<.0001 |
|
adult - subadult |
1417.57 |
159.7 |
8.875 |
<.0001 |
|
adult - Unknown |
1485.9 |
147.1 |
10.103 |
<.0001 |
|
juvenile - subadult |
-170.16 |
100.7 |
-1.69 |
0.3287 |
|
juvenile - Unknown |
-101.83 |
87.6 |
-1.162 |
0.6507 |
|
subadult - Unknown |
68.33 |
113 |
0.605 |
0.9307 |
|
Species = H. pustulatus, Source = Unknown |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
112.99 |
90.9 |
1.243 |
0.5996 |
|
adult - subadult |
174.92 |
79.9 |
2.189 |
0.1261 |
|
adult - Unknown |
97.98 |
88.2 |
1.11 |
0.6832 |
|
juvenile - subadult |
61.93 |
89.2 |
0.694 |
0.8993 |
|
juvenile - Unknown |
-15.01 |
89.7 |
-0.167 |
0.9983 |
|
subadult - Unknown |
-76.94 |
86.7 |
-0.888 |
0.8113 |
|
Species = H. weberi, Source = Unknown |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
27.31 |
189.9 |
0.144 |
0.9989 |
|
adult - subadult |
-114.59 |
197.6 |
-0.58 |
0.9381 |
|
adult - Unknown |
-59.1 |
196.5 |
-0.301 |
0.9906 |
|
juvenile - subadult |
-141.89 |
78.3 |
-1.812 |
0.2675 |
|
juvenile - Unknown |
-86.4 |
76.9 |
-1.123 |
0.6751 |
|
subadult - Unknown |
55.49 |
95.2 |
0.583 |
0.9372 |
|
Species = Hydrosaurus
spp., Source = Unknown |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
322.55 |
92.5 |
3.487 |
0.0027 |
|
adult - subadult |
160.08 |
98.6 |
1.624 |
0.3648 |
|
adult - Unknown |
241.91 |
89.5 |
2.703 |
0.0347 |
|
juvenile - subadult |
-162.47 |
78.6 |
-2.067 |
0.1639 |
|
juvenile - Unknown |
-80.64 |
67.3 |
-1.198 |
0.6281 |
|
subadult - Unknown |
81.84 |
74.2 |
1.103 |
0.6878 |
|
Species = H. amboinensis, Source = Wild |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
766.57 |
218.9 |
3.502 |
0.0026 |
|
adult - subadult |
550.43 |
218.9 |
2.514 |
0.0577 |
|
adult - Unknown |
NA |
NA |
NA |
NA |
|
juvenile - subadult |
-216.13 |
143.9 |
-1.502 |
0.436 |
|
juvenile - Unknown |
NA |
NA |
NA |
NA |
|
subadult - Unknown |
NA |
NA |
NA |
NA |
|
Species = H. pustulatus, Source = Wild |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
-708.18 |
266 |
-2.663 |
0.0388 |
|
adult - subadult |
-692.22 |
272.6 |
-2.539 |
0.0541 |
|
adult - Unknown |
NA |
NA |
NA |
NA |
|
juvenile - subadult |
15.96 |
169.7 |
0.094 |
0.9997 |
|
juvenile - Unknown |
NA |
NA |
NA |
NA |
|
subadult - Unknown |
NA |
NA |
NA |
NA |
|
Species = H. weberi, Source = Wild |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
-793.86 |
318.2 |
-2.494 |
0.0607 |
|
adult - subadult |
-981.73 |
325.2 |
-3.019 |
0.0135 |
|
adult - Unknown |
NA |
NA |
NA |
NA |
|
juvenile - subadult |
-187.87 |
143.9 |
-1.306 |
0.5591 |
|
juvenile - Unknown |
NA |
NA |
NA |
NA |
|
subadult - Unknown |
NA |
NA |
NA |
NA |
|
Species = Hydrosaurus
spp., Source = Wild |
||||
|
Contrast |
Estimate |
SE |
Z ratio |
P value |
|
adult - juvenile |
-498.62 |
260 |
-1.918 |
0.2205 |
|
adult - subadult |
-707.06 |
271.7 |
-2.602 |
0.0458 |
|
adult - Unknown |
NA |
NA |
NA |
NA |
|
juvenile - subadult |
-208.44 |
164.1 |
-1.27 |
0.5818 |
|
juvenile - Unknown |
NA |
NA |
NA |
NA |
|
subadult - Unknown |
NA |
NA |
NA |
NA |