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Ancient environmental DNA (aeDNA) from lake sediments has yielded remarkable insights for the reconstruction of past ecosystems, including suggestions of late survival of extinct species. However, translocation and lateral inflow of DNA in sediments can potentially distort the stratigraphic signal of the DNA. Using three different approaches on two short lake sediment cores of the Yamal peninsula, West Siberia, with ages spanning only the past hundreds of years, we detect DNA and identified mitochondrial genomes of multiple mammoth and woolly rhinoceros individuals-- both species that have been extinct for thousands of years on the mainland. The occurrence of clearly identifiable aeDNA of extinct Pleistocene megafauna (e.g. >400 K reads in one core) throughout these two short subsurface cores, along with specificities of sedimentology and dating, confirm that processes acting on regional scales, such as extensive permafrost thawing, can influence the aeDNA record and should be accounted for in aeDNA paleoecology. [ABSTRACT FROM AUTHOR]

Terrestrial mammals shape their ecosystems, and mammalian community assemblages can be important indicators of ecosystem functioning and ecosystem changes over time. Numerous taxa of terrestrial mammals are currently threatened by habitat loss and face displacement to new geographical areas or systems to which they are less suited and where they may affect the original communities.Understanding past ecosystem changes is important for predicting future responses of species assemblages to changes in their environments. Thus, ecological and evolutionary history, as well as adaptive capacity, are important predictors of future population viability. Genomic and metagenomic approaches using environmental or ancient DNA offer a wealth of information regarding genome‐wide variation of changing communities or of taxonomic groups over time, which may help explain past changes and predict future responses of communities to changes in their environment; however, to date, such studies are relatively scarce.We review studies on environmental DNA and environmental genomics of terrestrial mammals to assess the potential of such approaches regarding past, contemporary, and future terrestrial ecosystems, identify inherent challenges, and discuss potential applications. We elaborate on lessons to be learned from mammal genomics of past ecosystems and compare metabarcoding with general metagenetic and metagenomic techniques. We provide a comprehensive overview of current applications, challenges, and future potential of environmental DNA with regards to terrestrial mammals.As current major challenges regarding mammalian eDNA we identify its scarcity and patchy distribution, along with the persistent necessity of genomic reference data. While the latter are steadily increasing, the former can only be tackled by explicitly mapping the environment to gain understanding of spatial eDNA distribution. Such understanding may facilitate informed choices of sample sites and substrates and, together with new sequencing techniques, this can allow mammalian eDNA to be maximally exploited as a source of biodiversity data. [ABSTRACT FROM AUTHOR]

Determining species distributions can be extremely challenging but is crucial to ecological and conservation research. Environmental DNA (eDNA) approaches have shown particular promise in aquatic systems for several vertebrate and invertebrate species. For terrestrial animals, however, eDNA‐based surveys are considerably more difficult due to the lack of or difficulty in obtaining appropriate sampling substrate. In water‐limited ecosystem where terrestrial mammals are often forced to congregate at waterholes, water and sediment from shared water sources may be a suitable substrate for noninvasive eDNA approaches. We characterized mitochondrial DNA sequences from a broad range of terrestrial mammal species in two different African ecosystems (in Namibia and Tanzania) using eDNA isolated from native water, sediment and water filtered through glass fibre filters. A hybridization capture enrichment with RNA probes targeting the mitochondrial genomes of 38 mammal species representing the genera/families expected at the respective ecosystems was employed, and 16 species were identified, with a maximum mitogenome coverage of 99.8%. Conventional genus‐specific PCRs were tested on environmental samples for two genera producing fewer positive results than hybridization capture enrichment. An experiment with mock samples using DNA from non‐African mammals showed that baits covering 30% of nontarget mitogenomes produced 91% mitogenome coverage after capture. In the mock samples, over‐representation of DNA of one species still allowed for the detection of DNA of other species that was at a 100‐fold lower concentration. Hybridization capture enrichment of eDNA is therefore an effective method for monitoring terrestrial mammal species from shared water sources. [ABSTRACT FROM AUTHOR]

Equid Herpesviruses (EHV) are pathogens of equid and non-equid hosts that can cause disease and fatalities in captivity and in the wild. EHVs establish latent infections but can reactivate, and most EHVs are shed via the nasal passage. Therefore, nasal swabs are generally used for EHV monitoring. However, invasive sampling of wild equids is difficult. While feces is a commonly used substrate for detecting other pathogens, to our knowledge EHVs have never been detected in feces of naturally infected equids. We systematically tested zebra feces for EHV presence by A) establishing nested PCR conditions for fecal DNA extracts, B) controlling for environmental EHV contamination, and C) large-scale testing on a free ranging zebra population. A dilution minimizing inhibition while maximizing viral DNA concentration was determined in captive Grévys zebra (Equus grevyi) fecal samples from individuals shedding EHV nasally. Sixteen of 42 fecal samples (38%) were EHV-positive. To demonstrate that the EHV positivity was not a result of environmental contamination, rectal swabs of wild zebras were screened (N = 18; E. quagga and E. zebra), and 50% were EHV-positive, indicating that the source of EHV in feces is likely the intestinal mucosa, and not post-defecation contamination. Out of 270 fecal samples of wild zebras 26% were EHV-positive. Quantitative PCRs showed that the amount of virus DNA in feces was not significantly lower than in other samples. In summary, fecal sampling facilitates large scale screening and may be useful to non-invasively investigate phylogenetic EHV diversity in wild and domestic equids. [ABSTRACT FROM AUTHOR]

Equine Herpesviruses (EHV) are common and often latent pathogens of equids which can cause fatalities when transmitted to non-equids. Stress and elevated glucocorticoids have been associated withEHVreactivation in domestic horses, but little is known about the correlation between stress and viral reactivation in wild equids. We investigated the effect of an environmental stressor (social group restructuring following a translocation event) on EHV reactivation in captive Grévy's zebras (Equus grevyi). A mare was translocated by road transport from Zoo Mulhouse, France, to join a resident group of three mares in Tierpark Berlin, Germany. We used an indirect sampling method to assess the frequency of EHV shedding for 14 days immediately after the translocation event (termed the 'experimental period'). The results were compared with those from two control periods, one preceding and one subsequent to the experimental period. In addition, we measured fecal glucocorticoid metabolite (fGCM) concentrations daily in all individuals from 6 days before, to 14 days after translocation. We found significantly higher EHV shedding frequencies during the experimental period, compared to each of the two control periods. All animals showed significantly elevated fGCM concentrations, compared to fGCM levels before translocation. Finally, we found that an increase in fGCM concentration was significantly associated with an increased likelihood of EHV shedding. Although the small number of animals in the study limits the conclusions that can be drawn from the study, taken together, our results support the hypothesis that environmental stressors induce viral reactivation in wild equids. Our results suggest that potentials stressors such as group restructuring and translocation should be considered in the management of zoological collections to reduce the risk of fatal EHV infections in novel hosts. Moreover, environmental stressors may play an important role in EHV reactivation and spread in wild equid populations. [ABSTRACT FROM AUTHOR]

Direct collection of samples from wildlife can be difficult and sometimes impossible. Non-invasive remote sampling for the purpose of DNA extraction is a potential tool for monitoring the presence of wildlife at the individual level, and for identifying the pathogens shed by wildlife. Equine herpesviruses (EHV) are common pathogens of equids that can be fatal if transmitted to other mammals. Transmission usually occurs by nasal aerosol discharge from virus-shedding individuals. The aim of this study was to validate a simple, non-invasive method to track EHV shedding in zebras and to establish an efficient protocol for genotyping individual zebras from environmental DNA (eDNA). A commercially available horse enrichment toy was deployed in captive Grévy's, mountain, and plains zebra enclosures and swabbed after 4-24 hr. Using eDNA extracted from these swabs four EHV strains (EHV-1, EHV-7, wild ass herpesvirus and zebra herpesvirus) were detected by PCR and confirmed by sequencing, and 12 of 16 zebras present in the enclosures were identified as having interacted with the enrichment toy by mitochondrial DNA amplification and sequencing. We conclude that, when direct sampling is difficult or prohibited, non-invasive sampling of eDNA can be a useful tool to determine the genetics of individuals or populations and for detecting pathogen shedding in captive wildlife. [ABSTRACT FROM AUTHOR]

The article offers the authors' insights on the study on the grazing behaviour among giraffes, typically browsing leaves of tall trees, in Hwange National Park, Zimbabwe. The study involved a total of 1107 giraffes from the national park, water hole areas and grasslands, in which it conducted a 180-hour-observation. They identified 21 grazing giraffes during the study period, despite the availability of woody food plants.

Background: Numerous factors like continuous habitat reduction or fragmentation for free-ranging giraffes (Giraffa camelopardalis) as well as e.g. suboptimal housing conditions for animals in captivity might lead to behavioural alterations as part of the overall adaptation process to the changing living conditions. In order to facilitate current and future studies on giraffe behaviour, a comprehensive ethogram was compiled based on existing literature, as well as observations on giraffes in the wild (Hwange National Park, Zimbabwe; Entabeni Game Reserve, South Africa), and in captivity (National Zoological Gardens of South Africa, Pretoria). Findings: The resulting ethogram lists 65 different behavioural patterns, which were described and grouped into seven categories: General activities, Abnormal repetitive behaviours, General interactions, Bull-Cow behaviour, Bull- Bull behaviour, Cow-Bull behaviour, Maternal behaviours, and Interactions by calves. The behaviours were further described regarding a presumed purpose, particularly with respect to social interactions and sexual behaviour. Contradictory descriptions from previous studies were considered and discussed in comparison with our own observations. Conclusions: This ethogram provides a basis for current and future studies by suggesting a terminology which can be used for harmonizing behavioural observations, thus helping to facilitate comparability of future results. Subsequently, a better understanding of the behavioural ecology of giraffes in the wild as well as in captivity could aid future conservation efforts. [ABSTRACT FROM AUTHOR]

Equine herpesviruses (EHV) are a major health concern for domestic and wild equids and represent one of the most economically important disease agents of horses. Most known EHVs are transmitted directly between individuals as a result of direct exposure to exudates and aerosols. However, accumulating evidence suggests that environmental transmission may play a role including air, water, and fomites. Here, we reviewed studies on environmental stability and transmission of EHVs, which may influence viral dynamics and the use of environmental samples for monitoring EHV shedding. [ABSTRACT FROM AUTHOR]