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Once distributed all over the Philippines, the endemic Philippine Crocodile (Crocodylus mindorensis) is nowadays threatened with extinction. It is estimated that less than 140 mature individuals live in the wild. Human activities like fishing and poaching, as well as land-use change and habitat conversion cause a continuing threat to the remaining populations. Therefore, designated protected areas (PAs) were evaluated with species distribution models (SDMs) and also to see if most suitable areas are covered by PAs in order to improve future conservation efforts. For this purpose, the existing IUCN-reserves were analysed for potential habitat suitability (combining bioclimatic and remote sensing variables), wetland occurrences and the human footprint index by using MaxEnt and QGIS. Based on species records, our final SDM showed high performance and revealed the climatically most suitable areas for the species, which were mostly on Luzon and Mindanao. However, only small parts of the climatically suitable wetlands are currently covered by reserves (0.3-46.3%). In addition, none of the species' records was located within a PA. The anthropogenic pressures in the reserves measured by human footprint index (considering eight variables i.e. 'population density', 'navigable waterways', 'crop lands' and 'roads') were diverse and varied between a low and moderate level. Most of the records were found in areas with a moderate human footprint. Considering the three criteria, 'Lake Lanao Watershed Reservation', 'Angat Watershed Forest Reserve District (Metro Water District)', 'Northern Sierra Madre Natural Park', 'Talaytay Protected Landscape' and 'Agusan Marsh Wildlife Sanctuary' revealed to be the most suitable conservation areas for C. mindorensis, whereas suitable areas outside PAs are highly recommended for further surveys. We recommend to declare Ligawasan Marsh, Mindanao as a PA as this area harbours a large population of C. mindorensis. The declaration of more climatically suitable areas with low level of human footprint to PAs is a necessary step for the long-term conservation of this endemic crocodile species. The current network of existing PAs needs improvement in order to provide well-suited and long-term protection for C. mindorensis. More surveys are also necessary to find hidden, so far overlooked populations and to assess C. mindorensis tolerance level for human impacts. [ABSTRACT FROM AUTHOR]

Turtles and tortoises are one of the world's most threatened vertebrates; more than half of the 352 currently recognised species are threatened. To implement the IUCN CPSG's One Plan Approach to Conservation, we herein analyse the available information from the Zoological Information Management System (ZIMS) to provide an overview of the species already held in zoos. A total of 252 species (71.6%) are currently kept in ZIMS institutions, with 138 of them listed as threatened (76.7% of all threatened turtles). Additional 26 (15 threatened) species are listed in the database Zootierliste (Zoo Animal List). Zoos keep 152 (84.4%) of 180 threatened and 110 out of 150 not threatened species and show a preference for keeping threatened species. Concerning threatened turtle species, nine are represented with more than 500 individuals in zoo collections, while 25 are only kept as single individuals or in same-sex-groups. More than half of the held species are only represented in one to ten zoos. Most species are kept in North America, Europe and Asia, where most of the ZIMS institutions are located. A total of 92 (59 threatened) species (37.1 % of all zoo-kept species) were successfully bred in 140 zoos (15.8 % of 888 ZIMS-institutions keeping turtles) in the last 12 months. There already exists a tendency towards breeding threatened species. Still, zoos could improve both conservation breeding networking and establish further conservation breeding programs to create reserve populations, which would be in broad fulfilment with the IUCN's One Plan Approach to Conservation. [ABSTRACT FROM AUTHOR]

Invasive species, such as the mainly aquatic African clawed frog Xenopus laevis, are a main threat to global biodiversity. The identification of dispersal corridors is necessary to restrict further expansion of these species and help to elaborate management plans for their control and eradication. Here we use remote sensing derived resistance surfaces, based on the normalised difference vegetation index (NDVI) and the normalised difference water index (NDWI) accounting for behavioural and physiological dispersal limitations of the species, in combination with elevation layers, to determine fine scale dispersal patterns of invasive populations of X. laevis in Portugal, where the frog had established populations in two rivers. We reconstruct past dispersal routes between these two invaded rivers and highlight high risk areas for future expansion. Our models suggest terrestrial dispersal corridors that connect both invaded rivers and identify artificial water bodies as stepping stones for overland movement of X. laevis. Additionally, we found several potential stepping stones into novel areas and provide concrete information for invasive species management. [ABSTRACT FROM AUTHOR]

Invasive species, such as the mainly aquatic African clawed frog Xenopus laevis, are a main threat to global biodiversity. The identification of dispersal corridors is necessary to restrict further expansion of these species and help to elaborate management plans for their control and eradication. Here we use remote sensing derived resistance surfaces, based on the normalised difference vegetation index (NDVI) and the normalised difference water index (NDWI) accounting for behavioural and physiological dispersal limitations of the species, in combination with elevation layers, to determine fine scale dispersal patterns of invasive populations of X. laevis in Portugal, where the frog had established populations in two rivers. We reconstruct past dispersal routes between these two invaded rivers and highlight high risk areas for future expansion. Our models suggest terrestrial dispersal corridors that connect both invaded rivers and identify artificial water bodies as stepping stones for overland movement of X. laevis. Additionally, we found several potential stepping stones into novel areas and provide concrete information for invasive species management. [ABSTRACT FROM AUTHOR]

One principle threat prompting the worldwide decline of amphibians is the introduction of nonindigenous amphibians. The African Clawed Frog, Xenopus laevis, is now one of the widest distributed amphibians occurring on four continents with ongoing range expansion including large parts of Europe. Species distribution models (SDMs) are essential tools to predict the invasive risk of these species. Previous efforts have focused on correlative approaches but these can be vulnerable to extrapolation errors when projecting species' distributions in nonnative ranges. Recent developments emphasise more robust process‐based models, which use physiological data like critical thermal limits and performance, or hybrid models using both approaches. Previous correlative SDMs predict different patterns in the potential future distribution of X. laevis in Europe, but it is likely that these models do not assess its full invasive potential. Based on physiological performance trials, we calculate size and temperature‐dependent response surfaces, which are scaled to geographic performance layers matching the critical thermal limits. We then use these ecophysiological performance layers in a standard correlative SDM framework to predict the potential distribution in southern Africa and Europe. Physiological performance traits (standard metabolic rate and endurance time of adult frogs) are the main drivers for the predicted distribution, while the locomotor performance (maximum velocity and distance moved in 200 ms) of adults and tadpoles have low contributions. Research Highlights: This article provides the first process‐based assessment of the potential future spread of Xenopus laevis in Europe. Compared to previously published correlative models the invasion risk may be much higher than expected. [ABSTRACT FROM AUTHOR]

The distribution and occurrence of a species in its habitat are inevitably linked to its ecology. To successfully monitor and protect species, it is important to investigate which species-specific factors influence its interactions with the environment. In this study, we focus on patterns in habitat use of the Sand Lizard (Lacerta agilis). Differences in seasonal as well as sex and size class-dependent habitat use have been reported from the edges of this species' range. To verify such trends in the core area of its distribution, we analyzed the habitat factors weather, microclimate, microhabitat structures, and time dependence, which may have an impact on the use of space of the Sand Lizard. Using generalized linear models, hypervolumes, density estimations, and Chi-squared tests, we found that the movement patterns of individuals can neither be described by time differences, climatic conditions, or habitat composition, nor do they show habitat- or weather-related differences of movement between sexes or size. Here we demonstrate that in the case of a population from the core of this species' distribution area in the Dellbrücker Heide (Germany), habitat use is solely influenced to a low degree by differences related to the ontogeny of Sand Lizards and does not depend on any of the other evaluated factors. These results are in enormous contrast to findings in populations from the periphery of their distribution, i.e., the United Kingdom, Latvia, Romania, Bulgaria, and the Pyrenees. This implies that seasonal habitat shifts are more extreme at the edges of the range of L. agilis, serving to compensate deteriorating habitat conditions in the periphery. [ABSTRACT FROM AUTHOR]