Frog eat frog: exploring variables influencing anurophagy

Background. Frogs are generalist predators of a wide range of typically small prey items. But descriptions of dietary items regularly include other anurans, such that frogs are considered to be among the most important of anuran predators. However, the only existing hypothesis for the inclusion of anurans in the diet of post-metamorphic frogs postulates that it happens more often in bigger frogs. Moreover, this hypothesis has yet to be tested

Assessing the effects of climate change on distributions of Cape Floristic Region amphibians

Climatic changes have had profound impacts on species distributions throughout time. In response, species have shifted ranges, adapted genetically and behaviourally or become extinct. Using species distribution models, we examined how changes in suitable climatic space could affect the distributions of 37 endemic frog species in the Cape Floristic Region (CFR) – an area proposed to have evolved its megadiversity under a stable climate, which is expected to change substantially in future. Species distributions were projected onto mean climate for a current period (1950 to 2000), hindcasted to palaeoclimate (Last Glacial Maximum; LGM ≈ 21 kya and Holocene Glacial Minimum; HGM ≈ 6 kya) and forecasted for two emissions scenarios (A2a and B2a) for the year 2080. We then determined the changes in area sizes, direction (longitude and latitude), fragmentation index and biotic velocity, and assessed if these were affected by life-history traits and altitude. We found that the biotic velocity at which the CFR amphibian community is expected to shift north (A2a ≈ 540.5 km/kya) and east (B2a ≈ 198 km/kya) far exceeds historical background rates (≈1.05 km/kya, north and west ≈ 2.36 km/kya since the LGM). Our models further suggest that the CFR amphibian community has already lost about 56% of suitable climate space since the LGM and this loss is expected to accelerate under future emission scenarios (A2a ≈ 70%; B2a ≈ 60%). Lastly, we found that highland species were more fragmented than lowland species between the LGM and current period, but that the fragmentation of lowland species between current and future climates is expected to increase

Characterising wetland hydrology and water quality in streams and wetlands of Khalong-la-Lithunya, Lesotho

Wetland hydrology is important in understanding wetland systems, evaluating wetland functions and processes and assessing wetland conditions. Wetlands assimilate and transform pollutants and nutrients ensuring that quality water is discharged from the wetland into streams. The objective of this study was to characterise wetland hydrology and evaluate the water quality so as to determine the ecological functioning of the Khalong-la-Lithunya wetland. Wetland hydrology and water quality of the three sub-catchments were monitored from October 2015 to March 2016. Water levels in piezometers were recorded once a month and monthly water levels data for the years 2010, 2011, 2012 and 2013 previously recorded by the Millennium Challenge Account-Lesotho (MCA-L) project were integrated to this study’s data. Rainfall, piezometer and stream water were similarly obtained once every month. These were analysed for δ2H and δ18O water stable isotopes and water quality parameters determined. The estimated overall hydro-period of Khalong-la-Lithunya from the years 2010 to 2016 was 11.4% of the sampled time. The wetland showed delayed response of piezometer water levels to rainfall and additional source of water to the wetland through sub-surface flow. The isotopic composition of piezometer and stream water showed that the water gets stored in the wetland before being discharged to the stream leading to a positive interaction between ground and surface water. Most water quality parameters (Na, pH, Mg, PO4 , COD, BOD, NO3, K, Ca, EC) were higher in streams than in piezometers and were mostly within WHO permissible limits. There was a poorer water quality index in streams (59.71) when compared to that of piezometers (53.67). The principal component analysis (PCA) indicated that the parameters that were responsible for the variation in water quality were related to natural hydro-chemical processes, anthropogenic factors and geology and soil constituents. Temporally most parameters were highest during dry months. Due to a short hydro-period, a delayed interaction between surface and ground water and a poorer stream water quality index, it is concluded that the wetland was not in a good condition. Thus, it is not adequately performing its ecological function

Impact assessment with different scoring tools: How well do alien amphibian assessments match?

Classification of alien species' impacts can aid policy making through evidence based listing and management recommendations. We highlight differences and a number of potential difficulties with two scoring tools, the Environmental Impact Classification of Alien Taxa (EICAT) and the Generic Impact Scoring System (GISS) using amphibians as a case study. Generally, GISS and EICAT assessments lead to very similar impact levels, but scores from the schemes are not equivalent. Small differences are attributable to discrepancies in the verbal descriptions for scores. Differences were found in several impact categories. While the issue of disease appears to be related to uncertainties in both schemes, hybridisation might be inflated in EICAT. We conclude that GISS scores cannot directly be translated into EICAT classifications, but they give very similar outcomes and the same literature base can be used for both schemes

Global COVID-19 lockdown highlights humans as both threats and custodians of the environment

The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness