Guanaco Research Articles

Human–wildlife conflicts in Patagonia: ranchers’ perceptions of guanacoLama guanicoeabundance

AbstractConflicts between people and wildlife have become widespread as people move to areas previously home to wildlife and as wild populations recover. In Patagonia, one of the main threats to guanacoLama guanicoeconservation is the animosity of sheep ranchers towards the species. As key stakeholders in guanaco conservation we assessed ranchers’ perceptions regarding guanaco abundance in Isla Grande de Tierra del Fuego, Argentina. We contrasted these perceptions with estimated guanaco abundance and explored the socio-ecological factors influencing perceptions and how perceptions of overabundance are rooted in contextual factors rather than actual abundance. We performed semi-structured interviews with ranchers from Isla Grande and estimated guanaco abundance independently using density surface modelling. Ranchers were divided into three categories depending on their perception of guanaco abundance: ‘too many’, ‘many’ and ‘normal’. Those in the ‘many’ and ‘normal’ categories perceived guanaco abundance as being similar to actual abundance, whereas those in the category ‘too many' overestimated guanaco abundance. The perceived issues affecting livestock production varied between categories, although feral dogs emerged as the main problem. Negative perceptions of the guanaco stemmed from ranchers' beliefs that the species reduces forage availability for livestock, and from their disappointment about the government's handling of concerns regarding livestock production. Greater understanding and integration of the human dimension in conservation are needed to design more inclusive and resilient management plans.

A novel method to analyse DART TOFMS spectra based on Convolutional Neural Networks: A case study on methanol extracts of wool fibres from endangered camelids

Monitoring the illegal trade of wool fibres of wild vicuña (Vicugna vicugna) and guanaco (Lama guanicoe) is highly desirable. The high market value of fleece from these camelid species poses a threat to their wild populations. A previous study showed that direct analysis in real time time-of-flight mass spectrometry (DART-TOFMS) effectively identifies wool fibres to species. Producing high-resolution data in a short period of time makes DART-TOFMS a reliable identification tool, even though data analysis can still be improved. The present study proposes a novel data analysing pipeline based on Convolutional Neural Networks (CNN), applicable to any kind of DART-TOF MS data. We tested our proposed method on keratin fibres of four camelid species (Vicugna vicugna: n = 19; Vicugna pacos: n = 20; Lama guanicoe: n = 20, and Lama glama: n = 20). Analyses showed that selecting 512 ions with the highest relative intensity provides the best resolution and yields 100% accuracy for species identification.

A look into the wild. Pathological analysis of a modern collection of guanacos from the Dry Chaco and its implications for South American camelid paleopathological studies

ObjectiveThis article evaluates the prevalence of lesions in a modern osteological collection of guanacos (Lama guanicoe) and discusses the potential of paleopathological data to assess human intervention and environmental stress. MaterialsA modern osteological collection of guanacos (NISP = 862) from north-western Córdoba, Central Argentina. MethodsThe prevalence of pathological specimens per skeletal element and the pathological index (Bartosiewicz et al., 1997) was used. The prevalence of arthropathies, trauma and infections was quantified. Additionally, thorn lesions in the autopodium were recorded. Results11.03 % of the specimens presented pathological changes and the mean pathological index was 0.01. Degenerative lesions were the most prevalent type (10.34 %), followed by traumatic (0.81 %) and infectious pathologies (0.12 %). Thorn lesions (2.55 %) were recorded especially in metapodials. ConclusionsGuanacos are exposed to the development of degenerative lesions, mainly in the autopodium and vertebrae. These lesions are probably common in camelids and should not be used to argue human management. Traumatic and infectious lesions are less frequent. SignificanceThis work provides baseline information for the paleopathological study of South American camelids and contributes to the characterization of a regionally endangered species. LimitationsThe nature of the faunal assemblage did not allow for direct correlations between pathologies and individual variables such as sex or age. Suggestions for further researchThe comparison of our results with other wild and domesticated modern populations would be valuable to expand the baseline information for paleopathological studies. The use of quantitative methods is encouraged for future comparative and diachronic studies.

Cabo Dos Bahías y el manejo del guanaco en la Patagonia argentina

In 2000, a massive die-off resulted in a drastic reduction of the guanaco (Lama guanicoe) population of Cabo Dos Bahías Reserve, Chubut, Argentina. This event became an emblematic example of guanaco population dynamics in which it is presumed that the lack of regulatory mechanisms induced a population excess that damaged forage resources to an extreme that the population crashed due to starvation. Although this case poorly represents the relevant ecological scenarios, it has a disproportionate influence on current debates regarding the management of guanaco populations. Some authors even claim that, unless guanaco populations are culled, this degradation process will propagate across Patagonian rangelands. In this paper we aimed to synthetize the available evidence and to socialize the results obtained after 15 years following guanaco and vegetation dynamics at Cabo Dos Bahías to contribute to the discussion on the causes and consequences of mentioned guanaco die-off. The available evidence shows that population density is compatible with forage availability and it is coupled with its inter-annual variability. Range condition at the reserve is similar or better, upon the indicator considered, than range condition at neighbouring ranches with traditional livestock management. Our analysis indicates that, although Cabo dos Bahías presented high guanaco densities, which fluctuated more than other populations, there is no evidence to support the lack of regulation, population excess or environmental damage. Finally, we discuss our results in the context of the current debate about guanaco management in Patagonia.

Paleoenvironmental changes in the Brazilian Pampa based on carbon and oxygen stable isotope analysis of Pleistocene camelid tooth enamel

ABSTRACTHere we present paleoenvironmental and paleoclimatic reconstructions of the Brazilian Pampa based on stable isotopes (δ13C, δ18O) in tooth enamel of the Pleistocene camelidsLama guanicoeandHemiauchenia paradoxafrom the Chuy Creek fossil assemblage, including oneH. paradoxafrom a stratigraphic level within a loess unit deposited during the Last Glacial Maximum (26.5–19 ka b2k). The δ13C results show that both species fed mostly on C3 plants, although the mixed diets ofL. guanicoeincluded ~30% C4 or CAM plants.H.paradoxahad C3 diets with <10% C4 or CAM plants. Both species exhibit higher δ18O and aridity indexes compared to other mammals from the assemblage, consistent with ingestion of18O‐enriched water from plants growing in arid/semi‐arid conditions. A comparison with δ13C of camelids from Argentina indicates the camelids from Chuy Creek fed on vegetation similar to that of Dry Pampa, Monte and Patagonic xerophytic steppes. Aridification and expansion of dry steppes in southern Brazil suggest a climate‐driven northeastwards shift of the Arid Diagonal of South America that may have contributed to local extinction of the Pleistocene megafauna. These Lateglacial environmental changes are reflected in the characteristics of the plant and mammalian assemblages of the modern Brazilian Pampa.

Gastrointestinal parasite diversity of South American camelids (Artiodactyla: Camelidae): First review throughout the native range of distribution.

In South America inhabit an endemic group of ungulates adapted to extreme environments: the South American camelids (SAC), a key component of the Andean biocultural heritage. Until today, SAC are the most important factor of Andean economies and social and ritual life. SAC include two wild species, the guanaco (Lama guanicoe) and the vicuña (Vicugna vicugna), and two domestic species, the llama (Lama glama) and the alpaca (Vicugna pacos). Endoparasitosis are one of the most common diseases in SAC, and have great economic and health relevance. Despite this, there is a lack of knowledge on this concern. The main objective of this work was to conduct the first systematic review of the diversity of gastrointestinal parasites of SAC throughout the entire native range of distribution and to identify several gaps in knowledge. The PRISMA protocol was performed and a total of 101 documents were summarized. At least 36 parasitic helminths and five Eimeria spp. were registered. This work highlights the need for a greater number of works to know with more certainty the parasitic fauna of camelids in the past and present, in order to achieve predictions that allow proper management of camelids for their future conservation. Furthermore, concerted research efforts are needed to understand the biology, epidemiology, diagnosis and distribution of the parasitosis of SAC along the entire distribution range to guide conservation decisions.

Evolution of Animal South American RVA Told by the NSP4 Gene E12 Genotype.

Rotavirus A (RVA) possesses a genome of 11 double-stranded (ds) RNA segments, and each segment encodes one protein, with the exception of segment 11. NSP4 is a non-structural multifunctional protein encoded by segment 10 that defines the E-genotype. From the 31 E-genotypes described, genotype E12 has been described in Argentina, Uruguay, Paraguay, and Brazil in RVA strains infecting different animal species and humans. In this work, we studied the evolutionary relationships of RVA strains carrying the E12 genotype in South America using phylogenetic and phylodynamic approaches. We found that the E12 genotype has a South American origin, with a guanaco (Lama guanicoe) strain as natural host. Interestingly, all the other reported RVA strains carrying the E12 genotype in equine, bovine, caprine, and human strains are related to RVA strains of camelid origin. The evolutionary path and genetic footprint of the E12 genotype were reconstructed starting with the introduction of non-native livestock species into the American continent with the Spanish conquest in the 16th century. The imported animal species were in close contact with South American camelids, and the offspring were exposed to the native RVA strains brought from Europe and the new RVA circulating in guanacos, resulting in the emergence of new RVA strains in the current lineages' strongly species-specific adaption. In conclusion, we proposed the NSP4 E12 genotype as a genetic geographic marker in the RVA strains circulating in different animal species in South America.

Histomorphological changes between short and long days in ovary guanacos (Lama guanicoe).

This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries.

Patterns of guanaco distribution and microhabitat use in Tierra del Fuego: From protected to sheep ranching areas

Wild herbivore distribution responds to habitat and forage availability modulated by predation risk and interspecific interactions. Nowadays, the study of distribution and abundance of wild and domestic herbivores have regained importance to understand and diminish conservation conflicts in productive lands worldwide. Contiguous ranching and protected areas have created conflicting scenarios when wild ungulate populations increase and redistribute in livestock rangelands, because of competition for food and disease transmission. Consequently, understanding wild ungulate distribution and density patterns is critical to inform efficient management strategies for livestock grazing and wild ungulate coexistence. Here we analyze guanaco (Lama guanicoe) density and distribution, and compare habitat and microhabitat use (plant biomass, species richness, and diversity) in a protected area and in surrounding sheep ranches of Tierra del Fuego. Density of guanaco was similar between protected area and ranches, but proportion of groups and average group size were larger on ranches, and total guanaco density was also higher outside than within the protected area, which contrasts with previous studies. Use of microhabitat features was also different between both management regimes. Guanaco used areas with higher vegetation biomass, plant composition and richness in the protected area than on ranches. These results suggest that both intrinsic (socio-biological) and extrinsic (forage availability and human disturbance) factors influence density and distribution patterns as well as microhabitat use by the guanaco, which have large implications for its conservation.

Phenological drivers of ungulate migration in South America: characterizing the movement and seasonal habitat use of guanacos

BackgroundMigration is a widespread strategy among ungulates to cope with seasonality. Phenology, especially in seasonally snow-covered landscapes featuring “white waves” of snow accumulation and “green waves” of plant green-up, is a phenomenon that many migratory ungulates navigate. Guanacos (Lama guanicoe) are native camelids to South America and might be the last ungulate in South America that migrates. However, a detailed description of guanacos´ migratory attributes, including whether they surf or jump phenological waves is lacking.MethodsWe quantified the migratory movements of 21 adult guanacos over three years in Patagonia, Argentina. We analyzed annual movement patterns using net squared displacement (NSD) and home range overlap and quantified snow and vegetation phenology via remotely sensed products.ResultsWe found that 74% of the individual guanacos exhibited altitudinal migrations. For migratory guanacos, we observed fidelity of migratory ranges and residence time, but flexibility around migration propensity, timing, and duration of migration. The scarce vegetation and arid conditions within our study area seemed to prevent guanacos from surfing green waves; instead, guanacos appeared to avoid white waves.ConclusionOur study shows that guanaco elevational migration is driven by a combination of vegetation availability and snow cover, reveals behavioral plasticity of their migration, and highlights the importance of snow phenology as a driver of ungulate migrations.

Guanaco colonisation of Tierra del Fuego Island from mainland Patagonia: Walked, swam, or by canoe?

AbstractAddressed here is the biogeographical‐vexing question of why the guanaco (Lama guanicoe) is the only large mammal on the big island of Tierra del Fuego, answered by comparing alternative colonisation hypotheses. A multidisciplinary examination was conducted into the archaeological, ecological, evolutionary, geographical, genomic, glacial and zoological past, plus distribution of native terrestrial vertebrates in the Patagonia of southern South America. Notable disparities exist between main Patagonia (2.5 species/10,000 km2) compared with Tierra del Fuego (1.8). In the similar‐sized area of mainland Patagonia just north of the Strait of Magellan there are 12 reptiles, 7 amphibians and 34 mammals = 53 total species; Tierra del Fuego has 13. Despite being the size of Switzerland and only 3.1 km from the mainland, Tierra del Fuego has no species of snakes, salamanders, frogs or turtles, only one lizard, one toad, nine small mammals, one carnivore and one ungulate, the Guanaco. An innovative proposal is made contrary to traditional thinking: Tierra del Fuego has relatively few native‐terrestrial vertebrates because they were decimated by major tephra‐ash fallout (2 to >15 cm) from the Holocene 7750 YBP (years before present) Hudson volcano, the biggest and most destructive eruption in Patagonia during the past 10,000 years that eradicated indigenous peoples, most terrestrial vertebrates and all Guanacos. Neither terrestrial vertebrates nor man were replenished from the adjacent mainland for 1000 years because the Strait of Magellan was a complete biogeographical barrier. Guanacos on Tierra del Fuego have lower genetic diversity compared with the mainland, suggesting it is a younger population. Empirical evidence and pivotal events of Patagonia's prehistory support one of three hypotheses: guanacos were introduced to Tierra del Fuego by early Holocene, guanaco‐dependent, indigenous peoples from the mainland who repopulated Tierra del Fuego utilising the newly invented, skilfully crafted, seaworthy bark canoe (Appendix S1–Resumen en Español).

Comparative anatomy of the skull of South American camelids. A contribution to their taxonomical identification

South American camelids (Lamini tribe) are represented by two genera and four species. Here we studied the skull anatomy of three of them, Lama glama, Lama guanicoe and Vicugna vicugna. The coexistence of these species in wide sectors of their distribution and the osteological homogeneity of these camelids constitute important factors that limit or even preclude identification at species level. This is particularly true in paleontological and archaeological contexts in which bones are the only elements to analyze, and complete or fragmentary remains are potentially recorded. Although some contributions dealing with interspecific differentiation of camelids are available currently, the clear distinction between these species through osteological remains is still a pending issue. The aim of this study was to find osteological characters that facilitate the determination of the analyzed species. For this, we analyzed a final sample comprised mainly adult specimens of 11 guanacos, 9 llamas and 18 vicuñas. We described and compared a diverse set of qualitative and quantitative osteological features of the skull, including foramina, processes, muscular scars, and other features of the cranium and mandible. The set of qualitative features included eight observations on the cranium and four on the mandible. The set of quantitative features included eight linear variables on the cranium and two on the mandible. We performed a Partial Least Squares Discriminant Analysis (PLS-DA) based on both qualitative and quantitative variables in order to differentiate camelids species. The best results were obtained when both types of variables were included in the analysis. The most robust characters for interspecific discrimination are those related to the muzzle, the mastoid foramen, the paraoccipital process, the lower incisors and the coronoid and condylar processes of the mandible. The morpho-functional meanings of some of these traits are discussed. This study can be considered as a contribution to future systematic studies and as a basic tool to carry out specific assignment of camelids through complete or partial remains in archaeological and paleontological contexts.

A new species of small Camelidae from the Late Pleistocene of Brazil

ABSTRACTCamelids have been known in South America since the late Pliocene, where they arrived from North America as part of the Great American Biotic Interchange (GABI). They became extinct in North America by the late Pleistocene, while surviving in the Southern Cone of South America and in high altitudes of the Andean region. Extinct South American camelids are generally included in the genera Palaeolama and Hemiauchenia, members of which are larger than modern species. We describe here a new, small species of the genus Hemiauchenia based on late Pleistocene specimens previously assigned to Lama guanicoe. This specimen lived in northeastern Brazil at 22 345–21 907 cal a bp, and had a diet composed mainly of C3 plants.

Paleodiet of Lamini camelids (Mammalia: Artiodactyla) from the Pleistocene of southern Brazil: insights from stable isotope analysis (δ13C, δ18O)

AbstractCamelids (Camelidae) were a diverse and widely distributed group in South America during the Pleistocene. According to the fossil record, three species inhabited southern Brazil in the recent past: Hemiauchenia paradoxa, Lama guanicoe, and Vicugna vicugna. The analysis of carbon and oxygen stable isotope ratios in bioapatite provides insight into the paleobiology of nonliving animals and the environment they used to inhabit. We applied this tool to investigate the diet of camelids from two geological localities in southern Brazil: Touro Passo and Santa Vitória Formations (H. paradoxa, n = 7; L. guanicoe, n = 6; V. vicugna, n = 4). Carbon stable isotopes from enamel, dentin, and bone indicated that H. paradoxa and L. guanicoe had diets comprising mostly C3 grasses, but the latter showed a broader diet due to one individual with a mixed diet, whereas V. vicugna had a mixed C3–C4 diet. These different foraging behaviors may have minimized interspecific competition and favored niche partitioning and the coexistence of related species. Combined oxygen and carbon isotope data showed a consistent diet according to climate, probably due to the greater availability in glacial periods of cool-season grasses, which mainly use the C3 photosynthetic pathway. Given their adaptations to grazing, the climate amelioration, followed by the loss of grasslands, likely had a great impact on camelid populations, leading to their extinction in southern Brazil. These results, therefore, contribute to the understanding of the dynamics of paleocommunities in this region.

Changes in foraging behaviour suggest competition between wild and domestic ungulates: Guanaco and domestic sheep in southern Patagonia

AbstractPrevious attempts to address the presence of interspecific competition between domestic livestock and wild ungulates have focused largely on habitat or dietary overlaps. Although overlaps in habitat or diet create opportunities for competition to occur between species, competition only results from such overlap if it affects one or both species negatively. Less attention has been afforded to possible behavioural modifications induced in wildlife by competition with domestic livestock. Here, we investigated the effects of the presence of livestock on feeding behaviour of guanaco (Lama guanicoe) in southern Patagonia, using focal sampling of individuals during foraging bouts, with instantaneous scan samples to estimate group behavioural budgets. We recorded guanaco bite and step rates, used as proxies of foraging intake and selectivity, from four different study sites over eight consecutive seasons. We also estimated sheep and guanaco densities per site, along with vegetation biomass availability. As in other ungulates, bite rates of guanaco appear to be highly flexible and generally increased with vegetation biomass availability. However, as sheep densities and thus additional grazing pressure increased, guanaco foraging strategy compensated by increasing bite rates when foraging vegetation was scarce, indicating further likelihood of competition. Additionally, scan samples indicated that the probability of guanaco feeding occurring at any one time was higher in areas shared with domestic sheep compared to national parks, suggesting guanaco have to focus more on feeding than other behaviours when sheep are present.

More than just meat: Carcass decomposition shapes trophic identities in a terrestrial vertebrate

Abstract Most food web models fail to account for the full complexity of interactions within a community, particularly where microbes are involved. Carcasses are microbe‐rich resources and may represent a common nexus for the macrobiome and microbiome, effectively uniting autotrophs, consumers, predators and microbiota. We evaluated the role of carcasses as multitrophic resources and explored dietary partitioning for a sexually dimorphic obligate scavenger known for its hierarchical social system. This study was set in a well‐studied community of camelids Vicugna, Lama guanicoe, pumas Puma concolor and Andean condors Vultur gryphus in the Andes. We hypothesized that condors, by feeding on trophically distinct dietary substrates within any given carcass, would have highly variable trophic position (TP) values. Furthermore, we expected that the microbial consumers within the carcass would inflate TP values in both, the carrion and the condors. Thus, we expected that the trophic heterogeneity within a carcass could facilitate sex‐based dietary partitioning in condors. We used a multifaceted approach to assess the foraging of Andean condors, using regurgitated pellet and bulk isotopic analyses, and also quantified the TP of the entire community of graminoids, camelids, camelid carrion, pumas, and female and male condors employing compound‐specific stable isotopes analysis of amino acids. Our analysis of condor pellets and bulk isotopes revealed non‐trivial plant consumption, close to 10% of condor diet. Isotope analysis of amino acids revealed that condors had highly variable TPs (2.9 ± 0.3) compared to pumas (3.0 ± 0.0) and camelids (2.0 ± 0.1), likely representing ‘trophic omnivory’, wherein the condors consume plants (TP = 1.0 ± 0.1) and microbe‐colonized carrion (2.3 ± 0.1). Female condors exhibited a TP (2.8 ± 0.2) lower than strict carnivory, suggesting that they consume more plant biomass in a carcass, while males (TP = 3.1 ± 0.3) are likely consuming more of the microbe‐rich animal tissue. Our study highlights that carcasses represent a trophically heterogeneous resource and that vertebrate scavengers can feed across trophic groups within the carcass, from autotrophs to secondary consumers, and from both the macrobiome and microbiome. Thus, integration of microbes in macroecological contexts can help to resolve trophic identity, and better characterize the importance of microbes in detritivorous and omnivorous species. Read the free Plain Language Summary for this article on the Journal blog.

New insights into the palaeodiet and paleoenvironment of the camelids (Lama guanicoe) based on a palynological analysis of mid-Holocene coprolites from Cueva Milodon Norte 1, Pueyrredón Lake, Patagonia, Argentina

The coprolites of archeological sites offer information about the paleobiology of organisms and paleoenvironment. Camelids were one of the main resources of hunter-gatherers inhabiting Patagonia and, therefore, the studies of the behavior of camelids from the Holocene are essential to increase the knowledge of human group dynamics. The aim of this study was to identify palaeodiet food items from the camelids in the Pueyrredón Lake area (Santa Cruz, Argentina) after the Hudson volcanic eruption (7800 cal. BP), and to contribute to the knowledge of the vegetation in the camelid home range. Camelid coprolites were collected from four archeological layers, which were dated between 5900 and 6260 cal. BP, in the site Cueva Milodón Norte 1 (47°00’S–72°15’W), in the area of the Pueyrredón Lake. Today, the vegetation of the area consists of a shrub-grass steppe near a deciduous forest of Nothofagus pumilio. According to a palynological analysis of coprolites, the dominant pollen types were Nothofagus, Asteraceae subf. Asteroideae, Cerastium and Poaceae, with concentrations of 24,000 to 111,000 grains/g. Among the putative diet items, pollen types with zoophilous dispersal were Asteraceae subf. Asteroideae, Cerastium and Acaena, while those with anemophilous dispersal were Poaceae and Nothofagus. The taxa currently growing in the Nothofagus forest include Onagraceae, Lathyrus and pteridophytes, such as Blechnum. The presence of these pollen types and spores suggests the use of the steppe and the forest by camelids in search of food.

Intra-site spatial analysis of lithic assemblage and refitting of an open-air site in a lacustrine landscape from central Patagonia

Puesto Roberts 1 -PR1- is an open-air archaeological site emplaced in a deflation sector that offer the possibility to investigate diverse lithic activities carried out by hunter-gatherers in central Patagonia Argentine. The site is located on the coast of Colhué Huapi lake, in Chubut province. In this work, we present a techno-morphological and intra-site spatial analysis of the lithic artifactual assemblage to discuss about stone tool production, lithic raw materials and to explore the activities that were carried out at the site. The action of post-depositional natural agents that may have caused the mobilization of materials and lithic refits are also analysed to bring insights into the spatial distribution of artifacts.The site is the result of the anthropogenic action, and the mobilization of certain materials produced mainly by the action of wind and water it was recognized. Different stages of knapping, lithic raw materials and lithic tools were recognized. Finally, PR1 is interpreted as an open-air campsite of short duration in its occupation on the late Holocene. Evidences of almost exclusive processing and consumption of carcass of Lama guanicoe were identified. This differs from sites recorded around the lake with chronologies similar to PR1, which show evidences of processing and consumption of fish. Therefore, PR1 contributes to the knowledge of the variability of human activities developed in this lacustrine landscape.

Late Holocene triangular lithic projectile points, their morphometric variability and hafting systems in the Southern Pampean Hills (Córdoba, Argentina)

The shape variability of triangular stone projectile points and their hafting systems are analyzed to understand the technological practices during the Late Holocene in the Southern Pampean Hills (Córdoba, Argentina). Archaeometric studies were carried out on archaeological triangular lithic projectile points and plant remains. We present results of geometric morphometrics, functional analysis for the determination of microwear use traces and analysis of FT-IR organic residue recovered from the basal and middle blade areas. Complementary anthracological investigations were developed for the taxonomic identification of plants for comparison with the organic remains recovered from the projectile points. Archaeological and actualistic samples come from two multicomponent archaeological sites of Ongamira valley, Córdoba, Argentina where camelids (Lama guanicoe) and cervids (Ozotoceros sp. and Mazama sp.) were the main hunted prey. From our results, we discuss previous typological approaches based on the similar shapes and different weapon systems for the various hunter-gatherer occupations during the Late Holocene. Accordingly, it is assumed that there is technological continuity at least for 2000 years (between 3900 and 1900 BP) not only in flaked stone technology but also in hafting practices based on the preparation of the base shape of triangular projectile points and the use of local plant resins.

Sarcoptic mange outbreak decimates South American wild camelid populations in San Guillermo National Park, Argentina.

Sarcoptic mange epidemics can devastate wildlife populations. In 2014, mange was first detected in vicuñas (Vicugna vicugna) and guanacos (Lama guanicoe) in San Guillermo National Park (SGNP), Argentina. This study describes the temporal dynamics of the outbreak, its effects on the park’s wild camelid populations between 2017–2019, and investigates the potential source of the epidemic. From May 2017 to June 2018, transect surveys indicated a sharp decrease in the density of living vicuñas and guanacos by 68% and 77%, respectively. By April 2019 no vicuñas or guanacos were recorded on transect surveys, suggesting their near-extinction in the park. Clinical signs consistent with mange (e.g., intense scratching, hyperkeratosis, alopecia) were observed in 24% of living vicuñas (n = 478) and 33% of living guanacos (n = 12) during surveys, as well as in 94% of vicuña carcasses (n = 124) and 85% of guanaco carcasses (n = 20) examined. Sarcoptes scabiei was identified as the causal agent by skin scrapings, and the cutaneous lesions were characterized by histopathology (n = 15). Genetic characterization revealed that mites recovered from seven vicuñas (n = 13) and three guanacos (n = 11) shared the same genotype, which is consistent with a single source and recent origin of the epidemic. Tracing the potential source, we identified a governmental livestock incentive program which introduced llamas (Lama glama) in areas adjacent to SGNP in 2009, some of which had alopecic scaling consistent with sarcoptic mange. Though at the time of our study no llamas with mange were available for confirmatory sampling, we hypothesize that the introduction of mange-infected llamas may have triggered the outbreak in wild camelids. This unprecedented event in SGNP had devastating effects on dominating herbivores with potentially profound cascading effects at the community and ecosystem levels.