The protection of the bat community in the Dupnisa Cave System, Turkey, following opening for tourism

Quantification of threats to bats at localized spatial scales for conservation and management

In a rapidly changing world, where species conservation needs vary by local habitat, concentrated conservation efforts at small spatial scales can be critical. Bats provide an array of value to the ecosystems they inhabit; many bat species are also of conservation concern. San Diego County, California, contains 22 of the 41 bat species that occur in the United States, 16 of which are on conservation watchlists. Thus, management of bat communities in San Diego County is a pressing need. Because bats exploit vast areas of the landscape and historical sampling strategies have shifted over time, a standardized way of prioritizing areas of the landscape for management would provide an integral asset to bat conservation. We leveraged long-term bat community survey data from sampling areas across San Diego County to prioritize areas with the most management need. We calculated two types of scores: species scores and threat scores. Species scores incorporated richness and conservation status, and threat scores included landscape level threats that bats could encounter. We found that urbanization, the presence of artificial lights, and areas sampled on unconserved land were all significantly associated with decreases in species richness. Further, using species and threat scores, each sampling area was placed into one of four conservation categories, in order from greatest to least conservation need, ranging from highest priority (high species score, high threat score) to lowest (low species score, low threat score). Additionally, we focused on sampling areas in which Townsend's big-eared bat (Corynorhinus townsendii) and/or pallid bat (Antrozous pallidus) occurred. These two species are of exceptional conservation concern in San Diego County and across the western United States. We identified urbanization, the presence of artificial lights, and areas sampled on unconserved land as threats that were all significantly associated with the absence of Townsend's big-eared bat, but not pallid bat. The strategy, methodology, and solutions proposed in our study should assist bat conservation and management efforts wherever bats occur, and can be extended to other species that require conservation attention.

Concentrations of radionuclides and trace elements in wetlands

Environmental risks in wetlands are considered with radionuclides and trace elements to understand pollution accumulation. In this study, we aimed to determine the levels of radiation and heavy metals in water systems and assess pollution configurations. Radionuclides (222Rn, 210Pb and 210Po) and trace elements (Ag, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Li, Mo, Ni, Pb, V and Zn) were measured to evaluate anthropogenic factors. Water pollution in wetlands was indicated by mean concentrations of 66.2 mBq/L for 222Rn, 3 mBq/L for 210Pb, 42 mBq/L for 210Po, 41 ppb for Zn, 37 ppb for Ba, 190 ppb for Fe and 481 ppb for Sr. These pollutants may be related to industrial facilities in Kırklareli city, Türkiye.

A before−after assessment of the response of mammals to tourism in a Brazilian national park

Worldwide, nature-based tourism is becoming more popular and important economically. However, there is still debate regarding its impact on wildlife in protected areas. We conducted a quasi-experimental study to investigate the effects of tourism on the mammal community of Cavernas do Peruaçu National Park, a priority area for conservation in Brazil. We used camera traps to survey tourist and non-tourist trails during 2011–2017, encompassing periods before and after tourism started in the Park. We used four metrics for assessment: species richness, probability of using trails, activity levels and daily activity patterns. After tourism began in the Park there was no significant change in species richness and the probability of using tourist trails either increased or remained stable for five of the six species assessed. The rock cavy Kerodon rupestris was the only species to be displaced from tourist areas and to show reduced overall activity on tourist trails after tourism began. The ocelot Leopardus pardalis showed reduced diurnal activity on tourist trails, an indication of temporal adjustment. Overall, our results show that the initial years of visitation at the Park had limited negative impacts on the target mammal species, supporting the possibility of accommodating tourism activity and effective conservation of wildlife in the region. However, it is essential to continue monitoring in the Park because of the expected growth in tourism and potential time lags in responses of species.

Towards evidence-based conservation of subterranean ecosystems

Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution-based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer-reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence-base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost-effective, and long-lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta-analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert-based information rather than scientific evidence, without quantitatively testing their effectiveness.

A 16S rRNA Gene-Based Metabarcoding of Phosphate-Rich Deposits in Muierilor Cave, South-Western Carpathians

Muierilor Cave is one of Romania's most important show caves, with paleontological and archeological deposits. Recently, a new chamber was discovered in the cave, with unique yellow calcite crystals, fine-grained crusts, and black sediments. The deposits in this chamber were related to a leaking process from the upper level that contains fossil bones and a large pile of guano. Samples were taken from the new chamber and another passage to investigate the relationship between the substrate and microbial community. Chemical, mineralogical, and whole community 16S rRNA gene-based metabarcoding analyses were undertaken, and the base of the guano deposit was radiocarbon dated. Our study indicated bacteria linked to the presence of high phosphate concentration, most likely due to the nature of the substrate (hydroxyapatite). Bacteria involved in Fe, Mn, or N cycles were also found, as these elements are commonly identified in high concentrations in guano. Since no bat colonies or fossil bones were present in the new chamber, a high concentration of these elements could be sourced by organic deposits inside the cave (guano and fossil bones) even after hundreds of years of their deposition and in areas far from both deposits. Metabarcoding of the analyzed samples found that ∼0.7% of the identified bacteria are unknown to science, and ∼47% were not previously reported in caves or guano. Moreover, most of the identified human-related bacteria were not reported in caves or guano before, and some are known for their pathogenic potential. Therefore, continuous monitoring of air and floor microbiology should be considered in show caves with organic deposits containing bacteria that can threaten human health. The high number of unidentified taxa in a small sector of Muierilor Cave indicates the limited knowledge of the bacterial diversity in caves that can have potential applications in human health and biotechnology.

Bats in a cave tourism and pilgrimage site in eastern India: conservation challenges

Caves and other subterranean habitats are crucial for the survival of many bat species, but often deteriorate as a result of visits by tourists. The aim of the study was to understand the conservation challenges associated with the cave dwelling bats at Gupteswar cave tourism and pilgrimage site in eastern India and to develop conservation recommendations. I counted bat populations and monitored tourist visits once per month for 12 months during September 2016–August 2017. Roosting and breeding activities of eight species of bats, including two nationally threatened species, were recorded from five caves. The number of bats counted during the 12 survey days was 785–940 individuals. Tourism activity occurred throughout the year but was higher during local festive seasons; the maximum number of tourist entries recorded in a single day was 2,769. Installation of gated entrances, scheduling of visits to control overcrowding, restriction of access to caves with maternity colonies during breeding seasons, and minimal use of electric bulbs for illumination would minimize disturbance to the bats. Installation of educational display boards would help to create awareness of the conservation importance of bats amongst the cave visitors.

Use of Long-Term Opportunistic Surveys to Estimate Trends in Abundance of Hibernating Townsend's Big-Eared Bats

The advent of broad-scale threats to bats such as white-nose syndrome and climate change highlights the need for reliable baseline assessment of their populations. However, few long-term, rigorously designed assessments of bat populations exist, particularly in western North America. Consequently, results of informal monitoring efforts are often the only data available upon which to base population assessments. We evaluated whether an opportunistic collection of surveys recorded over a 22-y period could be used to assess population trend of Townsend's big-eared bats (Corynorhinus townsendii) at Lava Beds National Monument in northern California. We used records of counts of hibernating bats conducted during 1991–2012 to estimate the number of bats in 52 individual caves as well as cumulatively. Seventeen of 22 caves surveyed in four or more years had an increasing trend in the number of hibernating bats. We estimated the cumulative annual growth rate over the period to be 1.79%. Stable or increasing number of hibernating Townsend's big-eared bats may be a result of management actions taken to limit disturbance of bats during maternity and hibernation seasons. We found no evidence that annual counts depressed the number of hibernating bats, thereby broadening monitoring options and the ability to link population trends to extrinsic factors. Our results demonstrate that opportunistically collected, long-term data sets may be useful for establishing first approximations of population trends for bats.