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1.
Nature ; 605(7909): 285-290, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35477765

RESUMO

Comprehensive assessments of species' extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4-7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened-confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods-agriculture, logging, urban development and invasive species-although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles-including most species of crocodiles and turtles-require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles.


Assuntos
Conservação dos Recursos Naturais , Extinção Biológica , Répteis , Jacarés e Crocodilos , Anfíbios , Animais , Biodiversidade , Aves , Mamíferos , Filogenia , Répteis/classificação , Medição de Risco , Tartarugas
2.
Conserv Biol ; 38(5): e14336, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248777

RESUMO

Marine elapid snakes are a diverse, predominantly Indo-West Pacific species group. The persistent removal of some species has an unquantified but potentially dire impact on populations. We conducted the first comprehensive review of the trade in marine elapid snakes based on published literature (1974-2022) and trade data from the only species (i.e., Hydrophis [Lapemis] curtus) whose trade is monitored internationally. Some species and populations were subjected to targeted harvest for their meat and skins for at least the last century; fisheries are possibly the most significant threat to populations of marine elapids, with the highest numbers being exploited either accidentally, incidentally, or opportunistically in Southeast Asian fisheries targeting other seafood, including demersal trawl and squid fisheries. Southeast Asia is the core region for exploitation of marine elapids. Annual offtake is >225,000 individuals of at least 8 species in the Gulf of Thailand. Of 72 recognized marine elapids (all non-CITES [Convention on International Trade in Endangered Species of Wild Fauna and Flora] species), Hydrophis curtus and Hydrophis cyanocinctus dominate the skin trade. Skins of H. curtus are traded mainly in East and Southeast Asia and, to some extent, Europe. Despite some baseline information on the trade of these species, the sustainability of their harvests, particularly in the context of the burgeoning and unmanaged nature of fisheries in the region, remains the major challenge. In an era of declining fish stocks, there has been an increasing trend to commercialize the harvest and use marine elapids that were once considered accidental bycatch and discarded. This trend will continue to pose a significant risk to these snakes unless appropriate fisheries and trade regulations are enforced. Applying the precautionary principle to prevent the overexploitation of sea snakes is an indispensable measure in which trade in regional populations should be regulated through CITES. Accordingly, management plans to identify core distribution regions of exploited species would be crucial for assigning national responsibilities to sustain species and populations in the long term.


Retos para la regulación del uso comercial de serpientes elápidas marinas en el Indo­Pacífico Resumen Las serpientes elápidas marinas son un grupo diverso de especies, predominante en el Indo­Pacífico Occidental. La eliminación persistente de algunas especies tiene un impacto no cuantificado pero potencialmente negativo sobre las poblaciones. Realizamos la primera revisión exhaustiva del comercio de serpientes elápidas marinas con base en la bibliografía publicada (1974­2022) y en los datos comerciales de la única especie (Hydrophis [Lapemis] curtus) cuyo mercado tiene monitoreo internacional. Algunas especies y poblaciones fueron objeto de capturas selectivas por su carne y pieles durante al menos el siglo pasado, las pesquerías son posiblemente la amenaza más importante para las poblaciones de elápidos marinos, ya que el mayor número se explota de forma accidental, incidental u oportunista en las pesquerías del sudeste asiático enfocadas en otros mariscos, incluidas las pesquerías demersales de arrastre y de calamar. El sudeste asiático es la principal región de explotación de elápidos marinos. La captura anual es >225,000 individuos de al menos ocho especies en el Golfo de Tailandia. De los 72 elápidos marinos reconocidos (ninguna especie está en CITES [Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres]), Hydrophis curtus e H. cyanocinctus dominan el mercado de pieles. La piel de H. curtus se comercializa principalemnte en el este y sudeste asiático y, hasta cierto punto, en Europa. Aunque se dispone de cierta información de referencia sobre el comercio de estas especies, la sostenibilidad de sus capturas, sobre todo en el contexto del auge y la falta de gestión de la pesca en la región, sigue siendo el principal reto. En una época de disminución de las poblaciones de peces, ha aumentado la tendencia a comercializar la captura y el uso de elápidos marinos que antes se consideraban capturas accidentales y se descartaban. Esta tendencia seguirá representando un riesgo importante para estas serpientes a menos que se apliquen las regulaciones pesqueras y comerciales adecuadas. La aplicación del principio de precaución para evitar la sobreexplotación de las serpientes marinas es una medida indispensable para regular el comercio de las poblaciones regionales a través de CITES. Por lo tanto, los planes de gestión para identificar las regiones núcleo de distribución de las especies explotadas serían cruciales para asignar responsabilidades nacionales para mantener las especies y las poblaciones a largo plazo.


Assuntos
Comércio , Conservação dos Recursos Naturais , Pesqueiros , Animais , Conservação dos Recursos Naturais/métodos , Oceano Pacífico , Oceano Índico , Espécies em Perigo de Extinção , Sudeste Asiático , Elapidae/fisiologia , Hydrophiidae/fisiologia
3.
J Environ Manage ; 341: 117987, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178541

RESUMO

Exploitation of wildlife represents one of the greatest threats to species survival according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Whilst detrimental impacts of illegal trade are well recognised, legal trade is often equated to being sustainable despite the lack of evidence or data in the majority of cases. We review the sustainability of wildlife trade, the adequacy of tools, safeguards, and frameworks to understand and regulate trade, and identify gaps in data that undermine our ability to truly understand the sustainability of trade. We provide 183 examples showing unsustainable trade in a broad range of taxonomic groups. In most cases, neither illegal nor legal trade are supported by rigorous evidence of sustainability, with the lack of data on export levels and population monitoring data precluding true assessments of species or population-level impacts. We propose a more precautionary approach to wildlife trade and monitoring that requires those who profit from trade to provide proof of sustainability. We then identify four core areas that must be strengthened to achieve this goal: (1) rigorous data collection and analyses of populations; (2) linking trade quotas to IUCN and international accords; (3) improved databases and compliance of trade; and (4) enhanced understanding of trade bans, market forces, and species substitutions. Enacting these core areas in regulatory frameworks, including CITES, is essential to the continued survival of many threatened species. There are no winners from unsustainable collection and trade: without sustainable management not only will species or populations become extinct, but communities dependent upon these species will lose livelihoods.


Assuntos
Ecossistema , Comércio de Vida Silvestre , Animais , Comércio , Animais Selvagens , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais
5.
Animals (Basel) ; 10(3)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131452

RESUMO

Ball pythons (family Pythonidae) remain a commonly exploited species, readily available for purchase in North America and Europe. We assessed the housing conditions of more than 5000 Ball pythons across six exotic pet expositions and 113 YouTube videos. We scored provisions for hygiene, mobility, shelter, substrate and water provision, based on the Royal Society for the Protection of Animals (RSPCA) minimum guidelines. We found most entities involved in this commercial enterprise are not providing housing conditions that meet the minimum welfare recommendations for Ball pythons, either publicly or privately. We found that breeders and vendors typically utilised small and highly restrictive enclosures, with dimensions that prevented occupants from extending their bodies to full and unrestricted natural length. Our study also highlights that most vendors are not providing adequate written husbandry guidance to potential consumers, either at exotic pet expositions, on their commercial website, or on associated social media pages. Furthermore, our study also indicates that most potential consumers may themselves be unable to recognise unsuitable housing conditions that do not meet minimum animal welfare standards for Ball pythons. We suggest that more consistent guidance, adherence to agree principles and more potent operating models that are formally incorporated into relevant legislation would greatly aid existing and future efforts to safeguard animal welfare in this regard.

6.
Animals (Basel) ; 10(2)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979065

RESUMO

Extensive numbers of Ball pythons are caught, bred, traded and subsequently kept in captivity across the world as part of the exotic pet industry. Despite their widespread availability as pets, relatively little is known about the potential welfare challenges affecting them. We reviewed the literature for research focused on the health and welfare of Ball pythons in the international pet trade. From a total of 88 articles returned from the search criteria, our analysis showed that very few actually focused on trade (10%) or animal welfare (17%). Instead, the majority (64%) of articles focused on veterinary science. There was a considerable bias towards physical health, with most studies neglecting the four other domains of animal welfare (behaviour, nutrition, environment and mental health). Furthermore, very few studies considered Ball pythons prior to resulting pet ownership, during wild capture and transportation or captive breeding operations. Our review demonstrates that our current understanding of welfare for Ball pythons traded as exotic pets is limited. We recommend that future research should focus on aspects of the industry that are currently overlooked, including the potential consequences of genetic selection during captive-breeding and the conditions provided for snakes prior to and during international transportation.

7.
PLoS One ; 12(8): e0182049, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28817588

RESUMO

As an important economic natural resource in Southeast Asia, reticulated pythons (Malayopython reticulatus ssp.) are primarily harvested from the wild for their skins-which are prized in the luxury leather goods industry. Trade dynamics of this CITES Appendix II listed species are complex and management approaches on the country or regional level appear obscure. Little is known about the actual geographic point-of-harvest of snakes, how genetic diversity is partitioned across the species range, how current harvest levels may affect the genetic viability of populations, and whether genetic structure could (or should) be accounted for when managing harvest quotas. As an initial survey, we use mitochondrial sequence data to define the broad-scale geographic structure of genetic diversity across a significant portion of the reticulated python's native range. Preliminary results reveal: (1) prominent phylogenetic structure across populations east and west of Huxley's modification of Wallace's line. Thirty-four haplotypes were apportioned across two geographically distinct groups, estimated to be moderately (5.2%); (2) Philippine, Bornean and Sulawesian populations appear to cluster distinctly; (3) individuals from Ambon Island suggest recent human introduction. Malayopython reticulatus is currently managed as a single taxonomic unit across Southeast Asia yet these initial results may justify special management considerations of the Philippine populations as a phylogenetically distinct unit, that warrants further examination. In Indonesia, genetic structure does not conform tightly to political boundaries and therefore we advocate the precautionary designation and use of Evolutionary Significant Units within Malayopython reticulatus, to inform and guide regional adaptive management plans.


Assuntos
Filogenia , Filogeografia , Serpentes/classificação , Serpentes/genética , Animais , Sudeste Asiático , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Genética Populacional , Geografia , Haplótipos , Análise de Sequência de DNA
8.
Biol Rev Camb Philos Soc ; 92(3): 1539-1569, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27511961

RESUMO

Oil palm plantations have expanded rapidly in recent decades. This large-scale land-use change has had great ecological, economic, and social impacts on both the areas converted to oil palm and their surroundings. However, research on the impacts of oil palm cultivation is scattered and patchy, and no clear overview exists. We address this gap through a systematic and comprehensive literature review of all ecosystem functions in oil palm plantations, including several (genetic, medicinal and ornamental resources, information functions) not included in previous systematic reviews. We compare ecosystem functions in oil palm plantations to those in forests, as the conversion of forest to oil palm is prevalent in the tropics. We find that oil palm plantations generally have reduced ecosystem functioning compared to forests: 11 out of 14 ecosystem functions show a net decrease in level of function. Some functions show decreases with potentially irreversible global impacts (e.g. reductions in gas and climate regulation, habitat and nursery functions, genetic resources, medicinal resources, and information functions). The most serious impacts occur when forest is cleared to establish new plantations, and immediately afterwards, especially on peat soils. To variable degrees, specific plantation management measures can prevent or reduce losses of some ecosystem functions (e.g. avoid illegal land clearing via fire, avoid draining of peat, use of integrated pest management, use of cover crops, mulch, and compost) and we highlight synergistic mitigation measures that can improve multiple ecosystem functions simultaneously. The only ecosystem function which increases in oil palm plantations is, unsurprisingly, the production of marketable goods. Our review highlights numerous research gaps. In particular, there are significant gaps with respect to socio-cultural information functions. Further, there is a need for more empirical data on the importance of spatial and temporal scales, such as differences among plantations in different environments, of different sizes, and of different ages, as our review has identified examples where ecosystem functions vary spatially and temporally. Finally, more research is needed on developing management practices that can offset the losses of ecosystem functions. Our findings should stimulate research to address the identified gaps, and provide a foundation for more systematic research and discussion on ways to minimize the negative impacts and maximize the positive impacts of oil palm cultivation.


Assuntos
Produtos Agrícolas/fisiologia , Ecossistema , Florestas , Conservação dos Recursos Naturais , Solo
9.
Clin Toxicol (Phila) ; 50(6): 518-21, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22702902

RESUMO

CONTEXT: Envenoming by some species of cobras (Naja species) may include cardiotoxic effects including various dysrhythmias. However, dysrhythmias leading specifically to ventricular bigeminy have not been previously documented. We report a case of cardiotoxicity and the development of ventricular bigeminy following a cobra envenomation. CASE DETAILS: The patient was a 23-year-old man who presented to an emergency department following an alleged cobra bite. There was transient episode of nausea, vomiting, hypotension and tachycardia. The ECG showed infrequent ventricular ectopics that progressed to ventricular bigeminy and persisted even after the vital signs normalized. Complete resolution and resumption of normal sinus rhythm occurred following an empirical administration of monovalent antivenom against Naja kaouthia venom. The patient was discharged after 24 hours of uneventful observation. DISCUSSION: The patient's concomitant local effects, episodic cardiovascular instability and evolution of ventricular bigeminy support the likelihood of a venom-induced disease. Ventricular bigeminy can develop following a cobra envenomation. Thorough clinical evaluation, close serial observation of vital signs and early continuous cardiac monitoring are important in Naja spp. bites.


Assuntos
Venenos Elapídicos/toxicidade , Mordeduras de Serpentes/complicações , Complexos Ventriculares Prematuros/etiologia , Adulto , Eletrocardiografia , Humanos , Masculino
10.
Clin Toxicol (Phila) ; 48(3): 222-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20345298

RESUMO

INTRODUCTION: The Twin-Barred Tree Snake, Chrysopelea pelias, is a colubrine that, like other members of the genus Chrysopelea, is able to glide in the arboreal strata. Little is known about the effects of its bite. This report is the first clinically documented bite by this relatively uncommon rear-fanged species. CASE REPORT: The patient was a 19-year-old female who arrived at the Emergency Department (ED) of an urban teaching hospital 6 h after being bitten by a snake that was later provisionally identified as a C. pelias. Noted on presentation were bite marks on the right middle toe with minimal inflammation and tenderness. There was slight numbness over the dorsum of the right foot and discomforting sensation radiating up the thigh that persisted for several days. There was mild pyrexia, but no evidence of any systemic effects. The full blood count did show neutrophil leucocytosis, and transient hemoglobinuria was noted in an initial urine analysis. DISCUSSION: The properties of Duvernoy's secretion of C. pelias remain uncharacterized. In this case, the clinical course featured only the local effects noted above. However, the significant local pain reported by the patient suggests that bites by C. pelias are not necessarily trivial and do require full evaluation and observation in a medical facility. Discussed also is the importance of the establishment of a national registry for animal bites and stings in Malaysia. CONCLUSION: Such a facility could expedite safe and appropriate management of envenomed patients.


Assuntos
Colubridae , Mordeduras de Serpentes/fisiopatologia , Venenos de Serpentes/toxicidade , Animais , Serviço Hospitalar de Emergência , Feminino , Hemoglobinúria/etiologia , Hospitais de Ensino , Humanos , Leucocitose/etiologia , Malásia , Neutrófilos/metabolismo , Adulto Jovem
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