Effects of Environmentally Relevant Ammonium Nitrate Levels Caused by Agricultural Activities on Four Amphibian Species in The Eastern Black Sea Region

Within the scope of this research, the chronic effects of ammonium nitrate, which is the most widely used fertilizer worldwide, on the tadpoles of Marsh Frog (Pelophylax ridibundus), the Iranian Long-Legged Frog (Rana macrocnemis), the Caucasian Parsley Frog (Pelodytes caucasicus) and the Variable Green Toad (Bufotes variabilis) were examined. To assess the chronic effects of the fertilizer, the tadpoles of all the species were exposed to 0, 5, 10, 15, 20, 25 mg/L concentrations in same conditions. The chronic concentrations were applied from the 25th developmental stage to the 42nd developmental stage. It was defined at the end of the experiments that although there were some variability between different populations of the same species or between different species in the observed effects, chronic levels of ammonium nitrate caused decreased growth rate, prolonging in time to complete metamorphosis, increased abnormalities, and mortality in general. Among the 4 amphibian species, the Variable Green Toad was the most damaged one in terms of growth reduction (on average 31-41 %), abnormality rates (on average 50-75 %), prolonged time to complete metamorphose (14-21 days on average) and mortality rates (%54-100). The most adaptive species and the least damaged one was an Iranian long-legged frog for growth reduction (on average 0-15 %), prolonged time to complete metamorphose (7-9 days on average), and mortality rates (%9-15). All the harmful effects of chronic fertilizer levels caused by agricultural activities in the region had very important for examined species in our researches and it can be said that important environmental and biodiversity problems may occur if certain precautions are not taken regarding the use of the fertilizers and if the attitudes of the farmers on this issue cannot be changed.

Effects of Acute Ammonium Nitrate Levels Caused by Agricultural Activities on Four Amphibian Species in The Eastern Black Sea Region

The tadpoles of four amphibian species, namely the Marsh Frog (Pelophylax ridibundus), the Iranian Long-Legged Frog (Rana macrocnemis), the Caucasian Parsley Frog (Pelodytes caucasicus) and the Variable Green Toad (Bufotes variabilis), were exposed to acute concentrations (0 to 500 mg/L) of ammonium nitrate to assess the lethal effects (larval growth, abnormalities, mortality, and LC50 values). Eggs of each species were obtained from clean and polluted habitats in the same region and the tadpoles for experiments were provided from those eggs in the laboratory conditions. Although there was some variability between different populations of the same species or between different species in the observed effects, acute levels of ammonium nitrate caused decreased growth rate and increased abnormalities and mortality in general. Among the 4 amphibian species, the Variable Green Toad was the most damaged one in terms of growth reduction (on average 77-83%), and abnormality rates, and the most damaged one in terms of mortality rates was the Marsh Frog (on average 61-72%). Additionally, the species with the lowest concentration of ammonium nitrate, which killed half of its population, was the Marsh Frog. LC50 values for two populations of Marsh Frog were 37 and 59 mg/L. As a result of our research, it was determined that the acute fertilizer levels caused by agricultural activities in the region had very important harmful effects for all the species we examined. In this context, it can be said that very important environmental and biodiversity problems may occur if certain precautions are not taken regarding the use of the fertilizers and if the awareness of the farmers using these fertilizers cannot be raised.

Diversity of herpetofauna at restored cranberry bogs: A comparative survey of herpetofaunal diversity at a restored wetland in comparison to a retired cranberry bog to assess the restoration success

Wetlands perform critical ecological functions and provide wildlife habitats. Yet, wetland degradation continues at a global scale. In Massachusetts, USA, wetland restoration has reached remarkable heights, partly promoted by the retirement of cranberry bogs. In this study, to assess the effectiveness of cranberry-farm restoration for conservation of native herpetofauna, we surveyed both retired and restored cranberry bogs in south-eastern Massachusetts. Using both visual encounter surveys and baited aquatic traps, we documented herpetofaunal species and their relative abundance. Both survey methods combined, the cumulative herpetofaunal species richness at the restored bogs (16) exceeded that of the retired bogs (11). Our trap surveys indicated that the amphibian species richness at the retired bog was significantly greater than that of the restored bog. In contrast, reptilian species richness as well as the relative abundance of both amphibians and reptiles were significantly greater at the restored bog compared to the retired bog. Subsequent analyses we performed identified that greater habitat heterogeneity emerging from active restoration intervention was the underlying driver of elevated richness and abundance. Most frequently encountered herpetofauna at the restored versus retired bogs were habitat generalists with broader geographic ranges and are not of conservation concern. Our findings suggest that the restored bog we monitored is still in the early-recovery phase after active intervention. We urge the need for long-term herpetofaunal inventories via systematic, standard surveys to assess restoration success.

SPATIAL DISTRIBUTION AND SOCIO-ECONOMIC STATUS OF TRIBAL SETTLEMENTS IN THE WESTERN GHATS

The Western Ghats, also known as Sahyadri is a mountain range that covers an area of 140,000 square km parallel to the Western coast of the Indian Peninsula .It traverses the states of Kerala , Tamilnadu , Karnataka ,Goa ,Maharashtra, and Gujarat. It is a UNESCO world heritage site and is one of the eight hottest hot spots of biological diversity in the world. It covers 5000 species of flowering plants ,139 mammals species ,508 birds species, and 179 amphibian species ,many discovered species live in the Western Ghats . At least 325 globally threatened species occur in this region. The region glitches many anthropogenic intervention like illegal mining, the establishment of human settlement and deforestation etc. From a Historical view, the Western Ghats is the home for tribes > 50 types of tribes are living in the Western Ghats from the anecdotal period. The majority of the tribal are largely dependent on forests for their livelihood. After the implementation of the forest policy , the tribal livelihood status really worsened in the Western Ghats , they are unable to meet the daily requirement of recommended food intake >2500 Kcl. After post-independence (73years ) of India many development programs are implemented in the tribal area for improvement of livelihood status , but as of calendar date they are facing many problems like economic instability , lack of literacy , lower level of quality of life and not politically empowered . In this context , in the interest of policy implication at the tribal area , the present study was undertaken to study the socioeconomic status and spatial distribution of tribal in the Western Ghats. This study practically helps the policymakers , planners of the policy, and researcher scholars to extrapolate the tribal settlement through the geo-spacing tag of tribal , socio-economic level, Knowledge and attitude of Conservation of Western Ghats at the population level .

Near-Infrared Spectroscopy (NIRS) as a Method for Biological Sex Discrimination in the Endangered Houston Toad (Anaxyrus houstonensis)

Biological sex is one of the more critically important physiological parameters needed for managing threatened animal species because it is crucial for informing several of the management decisions surrounding conservation breeding programs. Near-infrared spectroscopy (NIRS) is a non-invasive technology that has been recently applied in the field of wildlife science to evaluate various aspects of animal physiology and may have potential as an in vivo technique for determining biological sex in live amphibian species. This study investigated whether NIRS could be used as a rapid and non-invasive method for discriminating biological sex in the endangered Houston toad (Anaxyrus houstonensis). NIR spectra (N = 396) were collected from live A. houstonensis individuals (N = 132), and distinct spectral patterns between males and females were identified using chemometrics. Linear discriminant analysis (PCA-LDA) classified the spectra from each biological sex with accuracy ≥ 98% in the calibration and internal validation datasets and 94% in the external validation process. Through the use of NIRS, we have determined that unique spectral signatures can be holistically captured in the skin of male and female anurans, bringing to light the possibility of further application of this technique for juveniles and sexually monomorphic species, whose sex designation is important for breeding-related decisions.

Improving kettle holes as habitat and reproduction areas for amphibians – a case study in organic farms in north-eastern Germany

Kettle holes are found in young moraine landscapes and serve as an important habitat for amphibians. The loss of amphibians has been dramatic in recent decades, mainly because of the increase in land use intensity and deterioration of habitats e.g., kettle holes in agricultural landscapes. We monitored amphibian species on three organically managed farms in north-eastern Germany to get an overview of their occurrence and proof of reproduction to develop effective protection strategies. From 2016 to 2020, we investigated 50 kettle holes in cultivated fields. In 2018, we implemented the nature conservation measure ‘cutting back dense wooded belts’ in six of these kettle holes. Here, we focused on seven species considering four highly endangered species. We found six to seven species in up to 17 kettle holes in the 44 kettle holes without the measure ‘cutting back dense wooded belts’. Bombina bombina occurred at the most kettle holes (57%). The number of kettle holes where amphibians reproduced differed strongly. On average, at least one species reproduced at 58% of the kettle holes. Many kettle holes become overgrown with negative effects for amphibians due to the reduction in solar irradiation and higher water consumption. The nature conservation measure increased the number of species on average from two to four and the number of species with reproduction from one to three. It is one of more than 100 measures in the ‘Farming for Biodiversity’ project that farmers can choose to receive a nature conservation certificate, which can be used for marketing purposes.

The «Empty Forest Syndrome» and the Herpetofaunal Communities in Laos (South-Eastern Asia)

Nowadays, Laos remains one of the scientifically least known countries of Asia in terms of herpetological knowledge. Here, we evaluate composition of species in freshwater ecosystems (main river courses) and terrestrial ecosystems (forests) in two distinct regions using Visual Encounter Surveys along designed transects, examination of fishers’ catches and standardized interviews. In Northern Laos, we recorded only 18 reptile individuals (2 turtle and 1 snake species). Interview surveys demonstrated that in Nam Xam River, fishers are more likely to hunt turtles and we identified one potential site where the world’s rarest turtle, Rafetus swinhoei, could be still present in the wild. In Nam Et Phou Louey National Park, we found 19 reptile species (8 lizard, 10 snake, 1 turtle species) in the different study sites, demonstrating a low species density in all different surveyed habitats. In Central/Southern Laos, we observed 30 species of reptiles (14 snake, 16 lizard, 35 amphibian species). Our study offers preliminary insights into the composition of amphibians and reptiles in Laos. The great majority of the species were non-threatened or not evaluated, and a few were threatened, suggesting that more research is needed to proper understand the conservation status of Laos’ herpetofauna. We highlighted, indirectly by interviews with local fishers, the possible presence of the turtle Rafetus swinhoei, thus providing a new hope for avoiding the extinction of this species. Finally, we observed a relatively low number of species in each habitat type, which is remarkably lower than in tropical forests of other continents or of nearby south-east Asian countries, indicating that the herpetofauna communities in Laos are depleted, reflecting an ‘empty forest syndrome’.

First record of ranavirus (Ranavirus sp.) in Siberia, Russia

Ranaviruses are a group of double-strand DNA viruses that infect fish, amphibians and reptiles. These viruses are responsible for mass fish and amphibian mortality events worldwide, both in the wild and at the fish and amphibian farms. The number of detected epizootics has grown significantly in recent years. In Eastern Europe and Northern Asia, including Russia, very few ranavirosis monitoring studies have been conducted, in contrast with Western Europe and America. In the present work, we used a qPCR assay to survey for the first time the amphibian populations of West Siberia (Russia) for the presence of ranaviruses. In total, we studied 252 tissue samples from six amphibian species, collected across West Siberia from the south to the Arctic regions. We report a single infected sample: a common toad (Bufo bufo) captured near Tyumen city. The phylogenetic analysis showed that the detected virus strain belongs to the CMTV lineage. This is only the second observation of Ranavirus in Russia.

Long distance homing in the cane toad (Rhinella marina) in its native range

Many animals exhibit complex navigation over different scales and environments. Navigation studies in amphibians have largely focused on species with life histories that require accurate spatial movements, such as territorial poison frogs and migratory pond-breeding amphibians that show fidelity to mating sites. However, other amphibian species have remained relatively understudied, leaving open the possibility that well-developed navigational abilities are widespread. Here, we measured short-term space use in non-territorial, non-migratory cane toads (Rhinella marina) in their native range in French Guiana. After establishing site fidelity, we tested their ability to return home following translocations of 500 and 1000 meters. Toads were able to travel in straight trajectories back to home areas, suggesting navigational abilities similar to those observed in amphibians with more complex spatial behavior. These observations break with the current paradigm of amphibian navigation and suggest that navigational abilities may be widely shared among amphibians.