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1.
Glob Chang Biol ; 30(7): e17399, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39007251

RESUMEN

The ever-increasing and expanding globalisation of trade and transport underpins the escalating global problem of biological invasions. Developing biosecurity infrastructures is crucial to anticipate and prevent the transport and introduction of invasive alien species. Still, robust and defensible forecasts of potential invaders are rare, especially for species without known invasion history. Here, we aim to support decision-making by developing a quantitative invasion risk assessment tool based on invasion syndromes (i.e., generalising typical attributes of invasive alien species). We implemented a workflow based on 'Multiple Imputation with Chain Equation' to estimate invasion syndromes from imputed datasets of species' life-history and ecological traits and macroecological patterns. Importantly, our models disentangle the factors explaining (i) transport and introduction and (ii) establishment. We showcase our tool by modelling the invasion syndromes of 466 amphibians and reptile species with invasion history. Then, we project these models to amphibians and reptiles worldwide (16,236 species [c.76% global coverage]) to identify species with a risk of being unintentionally transported and introduced, and risk of establishing alien populations. Our invasion syndrome models showed high predictive accuracy with a good balance between specificity and generality. Unintentionally transported and introduced species tend to be common and thrive well in human-disturbed habitats. In contrast, those with established alien populations tend to be large-sized, are habitat generalists, thrive well in human-disturbed habitats, and have large native geographic ranges. We forecast that 160 amphibians and reptiles without known invasion history could be unintentionally transported and introduced in the future. Among them, 57 species have a high risk of establishing alien populations. Our reliable, reproducible, transferable, statistically robust and scientifically defensible quantitative invasion risk assessment tool is a significant new addition to the suite of decision-support tools needed for developing a future-proof preventative biosecurity globally.


Asunto(s)
Anfibios , Predicción , Especies Introducidas , Reptiles , Animales , Reptiles/fisiología , Anfibios/fisiología , Medición de Riesgo/métodos , Modelos Teóricos , Modelos Biológicos
2.
Conserv Biol ; 38(5): e14355, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39248765

RESUMEN

Reptiles and amphibians are popular in the exotic pet trade, where Australian species are valued for their rarity and uniqueness. Despite a near-complete ban on the export of Australian wildlife, smuggling and subsequent international trade frequently occur in an unregulated and unmonitored manner. In 2022, Australia listed over 100 squamates in Appendix III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to better monitor this trade. We investigated current trade and assessed the value of this Australian CITES listing using web-scraping methods to monitor the online pet trade in Australian reptiles and amphibians, with additional data from published papers, trade databases, and seizure records. Despite the export ban, we identified 170 endemic herpetofauna (reptile and amphibian) species in international trade, 33 of which were not recorded previously in the international market, including 6 newly recorded genera. Ninety-two traded species were included in CITES appendices (59 added in 2022), but at least 78 other traded species remained unregulated. Among these, 5 of the 10 traded threatened species were unlisted, and we recommend they be considered for inclusion in CITES Appendix III. We also recommend the listing of all Diplodactylidae genera in Appendix III. Despite this family representing the greatest number of Australian species in trade, only one genus (of 7 traded) was included in the recent CITES amendments. Overall, a large number of Australian reptile and amphibian species are traded internationally and, although we acknowledge the value of Australia's recent CITES listing, we recommend the consideration of other taxa for similar inclusion in CITES.


Escala del mercado internacional no regulado de reptiles y anfibios australianos Resumen Los reptiles y anfibios son populares en el comercio de mascotas exóticas, en el que las especies australianas son valoradas por su rareza y singularidad. A pesar de la prohibición casi total de la exportación de fauna silvestre australiana, el contrabando y el comercio internacional posterior se producen con frecuencia de forma no regulada y no supervisada. En 2022, Australia incluyó más de 100 escamosos en el apéndice III de la Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres (CITES) para controlar mejor este comercio. Investigamos el comercio actual y evaluamos el valor de esta inclusión en CITES con métodos de raspado web para monitorear el comercio virtual de reptiles y anfibios australianos como mascotas, con datos adicionales de artículos publicados, bases de datos comerciales y registros de incautaciones. A pesar de la prohibición de las exportaciones, identificamos 170 especies endémicas de herpetofauna (reptiles y anfibios) en el comercio internacional, 33 de las cuales no se habían registrado previamente en el mercado internacional, incluidos 6 géneros registrados recientemente. Noventa y dos especies comercializadas se incluyeron en los apéndices de CITES (59 añadidas en 2022), pero al menos otras 78 especies comercializadas permanecieron sin regular. Entre ellas, cinco de las diez especies amenazadas comercializadas no estaban incluidas y recomendamos que se considere su inclusión en el apéndice III de CITES. También recomendamos la inclusión de todos los géneros de Diplodactylidae en el apéndice III. A pesar de que esta familia representa el mayor número de especies australianas en el comercio, sólo un género (de 7 comercializados) fue incluido en las recientes enmiendas de CITES. En general, un gran número de especies de reptiles y anfibios australianos son objeto de comercio internacional y, aunque reconocemos el valor de la reciente inclusión de Australia en CITES, recomendamos que se consideren otros taxones para su similar inclusión.


Asunto(s)
Anfibios , Comercio , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Reptiles , Animales , Reptiles/fisiología , Anfibios/fisiología , Australia , Conservación de los Recursos Naturales/legislación & jurisprudencia , Especies en Peligro de Extinción/legislación & jurisprudencia , Internacionalidad , Mascotas
3.
N Z Vet J ; 72(6): 334-340, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39079681

RESUMEN

CASE HISTORY: In 2023, the New Zealand Department of Conservation seized 63 endemic reptiles that were being held without a permit. This group included three adult female West Coast green geckos (Naultinus tuberculatus) that had been illegally removed from the wild 2 years earlier. They had been held in an outdoor enclosure with a pair of goldstripe geckos (Woodworthia chrysosiretica). CLINICAL FINDINGS: On physical examination, all three geckos had at least two soft palpable masses in the coelom. Repeated ultrasonographic examination over several months confirmed the diagnosis of pre-ovulatory follicular stasis (POFS) in each gecko, and in subsequent weeks, more ovarian follicles developed in each animal. LABORATORY FINDINGS: All three geckos were negative on culture of cloacal swabs for Salmonella spp., and negative on PCR assay of a cloacal flush for Cryptosporidium spp., despite other reptiles in the seized group showing positive results for multiple Salmonella spp., and one other gecko being positive for Cryptosporidium parvum, subtype IIcA5G3. TREATMENT AND OUTCOME: For all three geckos, para-midline ventral coeliotomy was performed under general anaesthesia, and folliculectomy of degenerate ovarian follicles was performed. Post-operative complications were seen in all three animals, which developed suture-line infections following disruption of normal skin shedding and entrapment of shed keratin in the surgical sites. A second surgery was undertaken to remove impacted keratin and caseous inflammatory material from the surgical wounds of all three animals and buried sutures were placed to close the coelomic wounds. The geckos were treated with 20 mg/kg ceftazidime IM every second day for 2 weeks post-operatively. Subsequent ecdysis (skin shedding) occurred without complication and the geckos were released back to the wild 10 months after admission. CLINICAL RELEVANCE: The recommended treatment for POFS in reptiles is ovariectomy, which is not appropriate for wild animals. The use of folliculectomy to resolve preovulatory follicular stasis should be considered for animals where retaining reproductive ability is essential.


Asunto(s)
Lagartos , Folículo Ovárico , Animales , Femenino , Nueva Zelanda , Animales Salvajes
4.
Emerg Infect Dis ; 29(10): 1-7, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37735750

RESUMEN

The world's reptiles and amphibians are experiencing dramatic and ongoing losses in biodiversity, changes that can have substantial effects on ecosystems and human health. In 2022, the first Global Amphibian and Reptile Disease Conference was held, using One Health as a guiding principle. The conference showcased knowledge on numerous reptile and amphibian pathogens from several standpoints, including epidemiology, host immune defenses, wild population effects, and mitigation. The conference also provided field experts the opportunity to discuss and identify the most urgent herpetofaunal disease research directions necessary to address current and future threats to reptile and amphibian biodiversity.


Asunto(s)
Ecosistema , Salud Única , Humanos , Animales , Anfibios , Reptiles , Biodiversidad
5.
Glob Chang Biol ; 29(17): 4949-4965, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37401520

RESUMEN

Ecosystem disturbance is increasing in extent, severity and frequency across the globe. To date, research has largely focussed on the impacts of disturbance on animal population size, extinction risk and species richness. However, individual responses, such as changes in body condition, can act as more sensitive metrics and may provide early warning signs of reduced fitness and population declines. We conducted the first global systematic review and meta-analysis investigating the impacts of ecosystem disturbance on reptile and amphibian body condition. We collated 384 effect sizes representing 137 species from 133 studies. We tested how disturbance type, species traits, biome and taxon moderate the impacts of disturbance on body condition. We found an overall negative effect of disturbance on herpetofauna body condition (Hedges' g = -0.37, 95% CI: -0.57, -0.18). Disturbance type was an influential predictor of body condition response and all disturbance types had a negative mean effect. Drought, invasive species and agriculture had the largest effects. The impact of disturbance varied in strength and direction across biomes, with the largest negative effects found within Mediterranean and temperate biomes. In contrast, taxon, body size, habitat specialisation and conservation status were not influential predictors of disturbance effects. Our findings reveal the widespread effects of disturbance on herpetofauna body condition and highlight the potential role of individual-level response metrics in enhancing wildlife monitoring. The use of individual response metrics alongside population and community metrics would deepen our understanding of disturbance impacts by revealing both early impacts and chronic effects within affected populations. This could enable early and more informed conservation management.


Asunto(s)
Anfibios , Ecosistema , Animales , Anfibios/fisiología , Animales Salvajes , Especies Introducidas , Reptiles/fisiología
6.
Zoo Biol ; 42(5): 683-692, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37584298

RESUMEN

Modifications to UV irradiance for indoor housed herpetofauna can affect behavior and physiology. Low ultraviolet B (UVB) irradiance can result in vitamin D3 deficiency resulting in calcium metabolism disorders including metabolic bone disease and immune suppression. High UVB can result in skin and eye issues, which can be severe enough to cause shock and death. Using tools available for the assessment of UV light, including Ferguson zones and the UV working tool designed by the British and Irish Association of Zoos and Aquaria, we redesigned lighting in our indoor komodo dragon (Varanus komodoensis) habitat to better suit the UV requirements of this species, while studying changes in behavior and physiology. We measured serum vitamin 25-hydroxy D3 values in one male and one female komodo dragon before and after they were housed in indoor and outdoor habitats. We also measured behavior changes in our male komodo as he moved from an outdoor habitat, to an indoor habitat with changing UV irradiance. Our female komodo showed a 98% increase in vitamin D3 values after being moved outdoors, and laid her first clutch of eggs. Our male dragon's vitamin D3 remained consistent 200 days after moving inside. He did show increased activity when higher UV irradiance was available. Importantly, we found the UV lamps we used stopped producing desired UV irradiance within 3.5 months of regular use. We suggest all animal care facilities develop UV monitoring programs to research output and longevity of UVB lamps used in indoor herpetofauna habitats.


Asunto(s)
Colecalciferol , Lagartos , Masculino , Femenino , Animales , Rayos Ultravioleta , Animales de Zoológico , Piel , Lagartos/fisiología , Vitamina D
7.
Glob Chang Biol ; 28(24): 7217-7233, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36166319

RESUMEN

While linear infrastructures, such as roads and power lines, are vital to human development, they may also have negative impacts on wildlife populations up to several kilometres into the surrounding environment (infrastructure-effect zones, IEZs). However, species-specific IEZs are not available for the vast majority of species, hampering global assessments of infrastructure impacts on wildlife. Here, we synthesized 253 studies worldwide to quantify the magnitude and spatial extent of infrastructure impacts on the abundance of 792 vertebrate species. We also identified the extent to which species traits, infrastructure type and habitat modulate IEZs for vertebrate species. Our results reveal contrasting responses across taxa based on the local context and species traits. Carnivorous mammals were generally more abundant in the proximity of infrastructure. In turn, medium- to large-sized non-carnivorous mammals (>1 kg) were less abundant near infrastructure across habitats, while their smaller counterparts were more abundant close to infrastructure in open habitats. Bird abundance was reduced near infrastructure with larger IEZs for non-carnivorous than for carnivorous species. Furthermore, birds experienced larger IEZs in closed (carnivores: ≈130 m, non-carnivores: >1 km) compared to open habitats (carnivores: ≈70 m, non-carnivores: ≈470 m). Reptiles were more abundant near infrastructure in closed habitats but not in open habitats where abundances were reduced within an IEZ of ≈90 m. Finally, IEZs were relatively small in amphibians (<30 m). These results indicate that infrastructure impact assessments should differentiate IEZs across species and local contexts in order to capture the variety of responses to infrastructure. Our trait-based synthetic approach can be applied in large-scale assessments of the impacts of current and future infrastructure developments across multiple species, including those for which infrastructure responses are not known from empirical data.


Asunto(s)
Anfibios , Reptiles , Animales , Humanos , Vertebrados , Mamíferos/fisiología , Aves/fisiología , Ecosistema , Animales Salvajes
8.
Proc Biol Sci ; 286(1905): 20191020, 2019 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-31238850

RESUMEN

A growing body of research demonstrates the impacts of invasive alien plants on native animals, but few studies consider thermal effects as a driver of the responses of native organisms. As invasive alien plants establish and alter the composition and arrangement of plant communities, the thermal landscapes available to ectotherms also change. Our study reviews the research undertaken to date on the thermal effects of alien plant invasions on native reptiles, amphibians, insects and arachnids. The 37 studies published between 1970 and early 2019 portray an overall detrimental effect of invasive plants on thermal landscapes, ectothermic individuals' performance and species abundance, diversity and composition. With a case study of a lizard species, we illustrate the use of thermal ecology tools in plant invasion research and test the generality of alien plant effects: changes in thermoregulation behaviour in invaded landscapes varied depending on the level of invasion and lizard traits. Together, the literature review and case study show that thermal effects of alien plants on ectotherms can be substantial albeit context-dependent. Further research should cover multiple combinations of native/invasive plant growth forms, invasion stages and ectotherm traits. More attention is also needed to test causality along the chain of effects from thermal landscapes to individuals, populations and communities.


Asunto(s)
Ecosistema , Calor , Especies Introducidas , Plantas , Anfibios , Animales , Biodiversidad , Insectos , Lagartos
9.
Ecol Appl ; 29(8): e01993, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31400176

RESUMEN

Modern forest management seeks to balance multiple social, economic, and ecological goals. Different management approaches create different types of disturbances in a forest ecosystem and thus also differ in their impacts on plants, animals, and insects. Understanding these impacts is important for conservation of forest ecosystem function, but challenging due to the large spatial and temporal scale over which management occurs. Most past research has focused on relatively small areas, short time scales, and/or a small number of species. To address this, we examined the effects of two common silvicultural systems (even and uneven aged) on abundance and richness of three vertebrate taxa (birds, small mammals, and herpetofauna) over a two-decade period in a temperate hardwood forest in Missouri, USA. The two systems removed a similar amount of biomass overall, but differed in the intensity, number, and configuration of harvests applied. We found that vertebrate population responses varied by taxa, occurred at multiple spatial scales, and were concentrated in the period following the first harvest entry. Birds generally had the largest changes in relative abundance, both positive and negative, following management. Small mammals and reptiles had smaller, but generally positive, responses; amphibians were mixed. Bird species tended to respond in the same way to both silvicultural systems, while small mammals and herpetofauna did not respond consistently. Thus, for birds, the total amount of harvest disturbance across the landscape drives population responses, while for others the size and configuration of individual harvests is likely more important. Synthesizing results across the vertebrate community at large spatial and temporal scales allows managers to better understand trade-offs when making decisions that will affect wildlife in contrasting ways.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Biodiversidad , Aves , Bosques , Missouri
10.
Ecol Appl ; 29(8): e01995, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31483894

RESUMEN

Streamside management zones (i.e., riparian buffers; SMZs) are commonly implemented within managed forests to protect water quality but may also provide habitat for riparian-associated wildlife. Yet, little research has rigorously addressed the value of SMZs for wildlife, particularly for cryptic species such as amphibians and reptiles. Previous studies of herpetofauna within SMZs have focused on one or a few stream-associated species, and questions remain regarding variation among species or guilds and what role SMZs serve toward conservation of herpetofaunal diversity in managed forests. However, recent statistical advances have improved our ability to analyze large multi-species presence-absence data sets, accounting for low detection rates typical for some herpetofaunal species. Our study represents an extensive landscape-scale examination of herpetofaunal communities within SMZs using a multi-species occupancy approach. We conducted four replicate surveys at 102 headwater streams, spanning a gradient of SMZ widths and adjacent forest stand ages, within the Ouachita Mountains, Arkansas, USA. We used a hierarchical Bayesian community occupancy model to estimate species richness and species-specific occupancy responses to SMZ and overstory characteristics, accounting for variation in occupancy and detection attributable to site and sampling covariates. We documented high richness (37 species) within SMZs. Across the herpetofaunal community, occupancy and species richness were consistently positively associated with SMZ width, with maximum predicted richness of 30 species occurring at sites with buffers extending 51 m on either side of the stream. However, we documented considerable variation among groups and species within groups, underscoring the potential for different responses to forest management among taxa. Reptile predicted richness increased more rapidly up to SMZs of ~35 m, whereas maximum salamander predicted richness was not seen until an SMZ width of 55 m. Estimated salamander richness was highest within SMZs embedded in mature managed pine stands and was higher in SMZs comprised of a deciduous or mixed overstory vs. a pine overstory. Compared to salamanders, more anuran species showed high mean estimated occupancy (>75%) at narrower SMZs (<30 m). Collectively, our results indicate that SMZs surrounding small first-order streams in intensively managed forests not only protect water quality, but also can support diverse amphibian and reptile communities.


Asunto(s)
Anfibios , Reptiles , Animales , Teorema de Bayes , Biodiversidad , Tampones (Química) , Ecosistema , Bosques
11.
Parasitol Res ; 117(5): 1357-1370, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29516213

RESUMEN

Colombia is a megadiverse country with about 600 species of reptiles; however, there are few studies on species of hemoparasites found in this taxonomic group. Here, we document the presence of Plasmodium spp. in four species of reptiles from the northern part of the Orinoco-Amazon region in Colombia. Individuals analyzed in this study were captured in localities between 200 and 500 m altitude, in the department of Guaviare. Each sample was screened for haemosporidian parasites by using morphology and a nested polymerase chain reaction (PCR) protocol that targets the mitochondrial cytochrome b (cytb) gene. Four morphotypes of the genus Plasmodium were found; two of these species are re-described using morphological and molecular data (cytb). For the other two morphotypes, it was not possible to assign a described species. Among those, Plasmodium screened one species was only detected by microscopy. Considering the potential species diversity, it is possible that commonly used primers may not detect all species, reinforcing the importance of using microscopy in haematozoa surveys. There was no correspondence between the morphological traits associated with the subgenera and the phylogenetic relationships that we found in our analyses. Additionally, we found an expansion in the geographical distribution of these two species, and a new host for P. kentropyxi, demonstrating that studies of tropical herpetofauna and their parasites deserve more attention.


Asunto(s)
Citocromos b/genética , Lagartos/parasitología , Plasmodium/clasificación , Plasmodium/genética , Serpientes/parasitología , Animales , Colombia , Cartilla de ADN/genética , Lagartos/clasificación , Tipificación Molecular/métodos , Filogenia , Plasmodium/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Serpientes/clasificación
12.
Ecotoxicology ; 27(7): 819-833, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29492806

RESUMEN

Amphibians and reptiles are the two most endangered groups of vertebrates. Environmental pollution by pesticides is recognised as one of the major factors threatening populations of these groups. However, the effects of pesticides on amphibians and reptiles have been studied for few substances, which is partly related to the fact that these animals are not included in the mandatory toxicity testing conducted as part of environmental risk assessments of pesticides. Whether risks of pesticides to amphibians and reptiles are addressed by surrogate taxa used in risk assessment is currently under debate. In order to develop a scientifically sound and robust risk assessment scheme, information needs to be gathered to examine whether fish, birds and mammals are valid surrogates for amphibians and reptiles. We updated a systematic review of scientific literature that was recently published compiling toxicity data on amphibians and reptiles. The outcome of this review was analysed with the purposes to (1) compare endpoints from amphibians and reptiles with the available information from fish, birds and mammals, and (2) develop species sensitivity distributions (SSDs) for those substances tested in at least six amphibian species (no substances were found tested in at least six reptile species) to identify a candidate amphibian model species to be used as surrogate in risk assessment. A positive correlation was found between toxicity recorded on fish and amphibians, the former revealing, in general, to be more sensitive than the latter to waterborne pollutants. In the terrestrial environment, although birds and mammals were more sensitive than amphibians and reptiles to at least 60% of tested substances, just a few weak significant correlations were observed. As a general rule, homoeothermic vertebrates are not good surrogates for reptiles and terrestrial amphibians in pesticide risk assessment. However, some chemical-dependent trends were detected, with pyrethroids and organochlorine insecticides being more toxic to amphibians or reptiles than to birds or mammals. These trends could ultimately help in decisions about protection provided by surrogate taxa for specific groups of substances, and also to determine when risk assessment of pesticides needs to pay special consideration to amphibians and reptiles. The outcome of this review reflects that there is still much information needed to reduce uncertainties and extract relevant conclusions on the overall protection of amphibians and reptiles by surrogate vertebrates.


Asunto(s)
Aves , Peces , Mamíferos , Plaguicidas/toxicidad , Medición de Riesgo/métodos , Pruebas de Toxicidad , Anfibios , Animales , Reptiles
13.
Conserv Biol ; 30(2): 249-58, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26416506

RESUMEN

Habitat loss and degradation are primary threats to amphibians and reptiles, but the relative effects of common land uses on assemblages and the mechanisms that underlie faunal responses are poorly studied. We reviewed the effects of four prevalent types of habitat alteration (urbanization, agriculture, livestock grazing, and silviculture) on amphibian and reptile species richness and abundance by summarizing reported responses in the literature and by estimating effect sizes across studies for species richness in each land-use type. We then used a multinomial model to classify species as natural habitat specialists, generalists, and disturbed habitat specialists and examined variation in effect sizes for each land-use type according to habitat specialization categories. There were mixed conclusions from individual studies, some reporting negative, neutral, or positive effects of land use on species richness and total abundance. A large proportion of studies reported species-specific effects of individual species abundance. However, in our analysis of effect sizes, we found a general trend of negative effects of land use on species richness. We also demonstrate that habitat associations of common species and species turnover can explain variation in the effect of land use on herpetofauna. Our review highlights the pervasive negative effects of common land uses on amphibians and reptiles, the importance of identifying groups vulnerable to land-use change (e.g., forest-associated species) in conservation studies, and the potential influence of disturbance-associated species on whole assemblage analyses.


Asunto(s)
Ecosistema , Agricultura , Anfibios/fisiología , Animales , Biodiversidad , Conservación de los Recursos Naturales , Reptiles/fisiología , Urbanización
14.
Oecologia ; 180(1): 231-42, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26350785

RESUMEN

Grazing plays an important role in shaping ecological communities in human-related ecosystems. Although myriad studies have explored the joint effect of grazing and climate on plant communities, this interactive effect has rarely been studied in animals. We hypothesized that the effect of grazing on the reptile community varies along a climatic gradient in relation to the effect of grazing on habitat characteristics, and that grazing differentially affects reptiles of different biogeographic regions. We tested our hypotheses by collecting data on environmental characteristics and by trapping reptiles in four heterogeneous landscapes experiencing differing grazing intensities and distributed along a sharp climatic gradient. We found that while reptile diversity increased with grazing intensity at the mesic end of the gradient, it decreased with grazing intensity at the arid end. Moreover, the proportion of reptile species of differing biogeographic origins varied with the interactive effect of climate and grazing. The representation of species originating in arid biogeographic zones was highest at the arid end of the climatic gradient, and representation increased with grazing intensity within this area. Regardless of the climatic context, increased grazing pressure results in a reduction in vegetation cover and thus in changes in habitat characteristics. By reducing vegetation cover, grazing increased habitat heterogeneity in the dense mesic sites and decreased habitat heterogeneity in the arid sites. Thus, our results suggest that the same direction of habitat alteration caused by grazing may have opposite effects on biodiversity and community composition in different climatic contexts.


Asunto(s)
Biodiversidad , Clima , Ecosistema , Herbivoria , Ganado , Plantas , Reptiles , Agricultura , Alimentación Animal , Animales , Dieta , Humanos , Dinámica Poblacional , Agua
15.
Zookeys ; 1211: 29-55, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39262608

RESUMEN

In Mexico, land use changes have significantly impacted the diversity of amphibians and reptiles in a negative way. In light of this, we evaluate the alpha and beta components of the taxonomic diversity of amphibians and reptiles in a heterogeneous landscape in west-central Mexico. Additionally, we provide a checklist of amphibian and reptile species recorded over nine years of observations within the studied landscape and surrounding areas. The land cover/use types with the highest species richness and alpha taxonomic diversity differed between amphibians and reptiles. Overall beta taxonomic diversity was high for both groups, but slightly higher in reptiles. This taxonomic differentiation mainly corresponded to a difference in the turnover component and was greater in pristine habitats compared to disturbed ones. The checklist records 20 species of amphibians (ten of which are endemic) and 48 of reptiles (30 endemics). Additionally, the study expands the known geographical distribution range of one species of frog and three species of snakes. Our findings suggest that heterogeneous landscapes with diverse land cover/use types can provide essential habitats for the conservation of amphibian and reptile species.

16.
Ecol Evol ; 14(10): e70406, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39398633

RESUMEN

The Eastern Arc Mountains (EAM) and Coastal forests of Tanzania are renowned for harboring large number of threatened and endemic vertebrate species, yet most of these areas have been partially studied. The Kimboza Nature Forest Reserve (KNFR) is a small forest which is in transition between the EAM and Coastal forests, and among the poorly surveyed areas for amphibians and reptiles. We conducted systematic surveys across the KNFR in 2012 and between 2020 and 2023 using a range of approaches with the aim of establishing a comprehensive and updated list of reptile and amphibian species and assess the contribution of EAM and Coastal forests to the KNFR's herpetofauna. We identified 77 species, 29 amphibians and 48 reptiles, substantially updating previous species lists. Three of these species (Kinyongia magomberae, Trachylepis boulengeri and Philothamnus macrops) represent range extensions from previously known ranges. Fourteen species are endemic to East Africa, 11 of them being restricted to Tanzania. These results make the KNFR the richest forest reserve for herpetofauna per square km in Tanzania, and most similar in its composition to the Coastal, rather than Eastern Arc forests. With the caveats concerning taxonomic uncertainties and the inequalities of sampling intensity across the region, this study shows that the KNFR is an important area that deserves conservation attention. The KNFR, like other Coastal forests, is under significant pressure from anthropogenic activities which call for an urgent action to protect this small but rich forest.

17.
Environ Toxicol Chem ; 43(9): 1936-1949, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38967263

RESUMEN

Harmful algal blooms (HABs) are a persistent and increasing problem globally, yet we still have limited knowledge about how they affect wildlife. Although semi-aquatic and aquatic amphibians and reptiles have experienced large declines and occupy environments where HABs are increasingly problematic, their vulnerability to HABs remains unclear. To inform monitoring, management, and future research, we conducted a literature review, synthesized the studies, and report on the mortality events describing effects of cyanotoxins from HABs on freshwater herpetofauna. Our review identified 37 unique studies and 71 endpoints (no-observed-effect and lowest-observed-effect concentrations) involving 11 amphibian and 3 reptile species worldwide. Responses varied widely among studies, species, and exposure concentrations used in experiments. Concentrations causing lethal and sublethal effects in laboratory experiments were generally 1 to 100 µg/L, which contains the mean value of reported HAB events but is 70 times less than the maximum cyanotoxin concentrations reported in the environment. However, one species of amphibian was tolerant to concentrations of 10,000 µg/L, demonstrating potentially immense differences in sensitivities. Most studies focused on microcystin-LR (MC-LR), which can increase systemic inflammation and harm the digestive system, reproductive organs, liver, kidneys, and development. The few studies on other cyanotoxins illustrated that effects resembled those of MC-LR at similar concentrations, but more research is needed to describe effects of other cyanotoxins and mixtures of cyanotoxins that commonly occur in the environment. All experimental studies were on larval and adult amphibians; there were no such studies on reptiles. Experimental work with reptiles and adult amphibians is needed to clarify thresholds of tolerance. Only nine mortality events were reported, mostly for reptiles. Given that amphibians likely decay faster than reptiles, which have tissues that resist decomposition, mass amphibian mortality events from HABs have likely been under-reported. We propose that future efforts should be focused on seven major areas, to enhance our understanding of effects and monitoring of HABs on herpetofauna that fill important roles in freshwater and terrestrial environments. Environ Toxicol Chem 2024;43:1936-1949. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Anfibios , Floraciones de Algas Nocivas , Reptiles , Animales , Microcistinas/toxicidad , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad , Toxinas Marinas/toxicidad
18.
Biodivers Data J ; 12: e113770, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38314124

RESUMEN

Background: Only a few comprehensive studies have been carried out on parasites in amphibians and reptiles in Ukraine. This has resulted in identifying over 100 helminth species across these vertebrate groups. However, most of the studies were performed in the 20th century and the taxonomy of many parasites and their hosts has changed ever since, in addition to the discovery of new species and registrations of species that had not been previously known for Ukraine. In recent decades, there have been very few publications on helminths from amphibian or reptile hosts in this region. Notably, just one of these recent studies is a faunistic study, providing a list of helminths found in two species of green frogs - Pelophylaxridibundus (Pallas, 1771) and Pelophylaxesculentus (Linnaeus, 1758). Therefore, it is clear that publishing datasets of modern records of helminths in these vertebrate groups, based on modern taxonomy, is an essential step in further studies of their parasitic diversity. Additionally, such study is important in terms of global climate change, the growing number of possibilities of invasion of alien species (both hosts and parasites) that might potentially become a threat to native biota and growing anthropogenic pressure on local populations of hosts that affect the parasites as well. In future, this study is planned to be used for the creation of a checklist of helminths of the herpetofauna of Ukraine. The present dataset is an inventory of various species of helminths parasitising common species of the herpetofauna in central, northern, western and southern Ukraine recorded during field studies in the 2021-2023 period. New information: The dataset is the first one to represent the up-to-date and unified data on helminths of reptiles and amphibians of Ukraine. Previously, records of this group of organisms with reference to their hosts were presented as several separate records within the country. Currently, this is the largest dataset presenting geocoded records of non-human-related helminths in the fauna of Ukraine. It reports helminth species from 15 hosts (205 individuals), including eight amphibians and seven reptilian species found in various Ukrainian regions. A total of 47 helminth species have been documented in the research and during 2021-2023 period on the territory of northern (Kyiv and Zhytomyr), western (Lviv, Zakarpattia Ivano-Frankivsk), central (Vinnytsia, Dnipropetrovsk, Cherkasy, Zaporizhzhia and Poltava) and southern (Odesa) regions of Ukraine. The identified helminth species belong to the following phyla: Acanthocephala (Centrorhynchidae (2), Echinorhynchidae (2)); Nematoda (Acuariidae, Anisakidae, Cosmocercidae (3), Dioctophymatidae, Gnathostomatidae (1), Kathlanidae (1), Molineidae (7), Onchocercidae (1), Pharyngodonidae (1), Rhabdiasidae (6), Strongyloididae); Platyhelminthes (Diplodiscidae (1), Diplostomidae (2), Encyclometridae (1), Haematoloechidae (1), Leptophallidae (2), Macroderidae (1), Mesocestoididae, Opisthorchiidae (2), Plagiorchiidae (3), Pleurogenidae (2), Polystomatidae (3), Proteocephalidae (1), Strigeidae (1) and Telorchiidae (3)). Only some helminths in the dataset were not identified to species level. Material is stored in the collection of the department of Parasitology of the I. I. Schmalhausen Institute of Zoology NAS of Ukraine.

19.
Animals (Basel) ; 14(5)2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38473093

RESUMEN

The pervasive expansion of human-engineered infrastructure, particularly roads, has fundamentally reshaped landscapes, profoundly affecting wildlife interactions. Wildlife-vehicle collisions, a common consequence of this intricate interplay, frequently result in fatalities, extending their detrimental impact within Protected Areas (PAs). Among the faunal groups most susceptible to road mortality, reptiles and amphibians stand at the forefront, highlighting the urgent need for global comprehensive mitigation strategies. In Greece, where road infrastructure expansion has encroached upon a significant portion of the nation's PAs, the plight of these road-vulnerable species demands immediate attention. To address this critical issue, we present a multifaceted and holistic approach to investigating and assessing the complex phenomenon of herpetofauna road mortality within the unique ecological context of the Lake Karla plain, a rehabilitated wetland complex within a PA. To unravel the intricacies of herpetofauna road mortality in the Lake Karla plain, we conducted a comprehensive 12-year investigation from 2008 to 2019. Employing a combination of statistical modeling and spatial analysis techniques, we aimed to identify the species most susceptible to these encounters, their temporal and seasonal variations, and the ecological determinants of their roadkill patterns. We documented a total of 340 roadkill incidents involving 14 herpetofauna species in the Lake Karla's plain, with reptiles, particularly snakes, being more susceptible, accounting for over 60% of roadkill occurrences. Moreover, we found that environmental and road-related factors play a crucial role in influencing roadkill incidents, while spatial analysis techniques, including Kernel Density Estimation, the Getis-Ord Gi*, and the Kernel Density Estimation plus methods revealed critical areas, particularly in the south-eastern region of Lake Karla's plain, offering guidance for targeted interventions to address both individual and collective risks associated with roadkill incidents.

20.
Biodivers Data J ; 11: e98142, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37206112

RESUMEN

Even though the reptiles and amphibians of Cyprus are of scientific and conservation importance and although several books, guides and scientific reports have been published the past 30 years, there is a clear absence of a systematic recording and archiving scheme of all available data in a structural database. Towards this end, the Cyprus Herp (= reptiles and amphibians) Atlas has been developed. The Atlas constitutes the first effort to collect all existing locality data of the herpetofauna species of the island (i.e. scientific reports, books, journals, grey literature) in a single database and simultaneously promote a citizen-science approach in order to collect and constantly update the database with new records. The website of the Atlas contains basic educational and informational material for the public, along with the visibility tool of the database in the form of occurrence maps, in 5 km x 5 km grid cells, openly available for download in kmz format. The Atlas is a powerful tool for citizens, scientists and decision-makers, aiming to contribute to the study and conservation of the reptile and amphibian species of Cyprus. In this short communication, we give details on the structure of the Atlas.

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