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1.
Glob Chang Biol ; 30(10): e17528, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39400406

RESUMO

Assessing genetic structure and diversity in wildlife is particularly important in the context of climate change. The Arctic is rapidly warming, and endemic species must adapt quickly or face significant threats to persistence. Bowhead whales (Balaena mysticetus) and narwhals (Monodon monoceros) are two long-lived Arctic species with similar habitat requirements and are often seen together in the Canadian Arctic. Although their ranges overlap extensively, bowhead whales experienced significantly greater commercial whaling mortality than narwhals over several centuries. The similar habitat requirements but different harvest histories of these two species provide an opportunity to examine present-day genetic diversity and the demographic and genetic consequences of commercial whaling. We whole-genome resequenced contemporary Canadian Arctic bowhead whales and narwhals to delineate population structure and reconstruct demographic history. We found higher genetic diversity in bowhead whales compared to narwhals. However, bowhead whale effective population size sharply declined contemporaneously with the intense commercial whaling period. Narwhals, in contrast, exhibited recent growth in effective population size, likely reflecting exposure to limited opportunistic commercial harvest. Bowhead whales will likely continue to experience significant genetic drift in the future, leading to the erosion of genetic diversity. In contrast, narwhals do not seem to be at imminent risk of losing their current levels of genetic variation due to their long-term low effective population size and lack of evidence for a recent decline. This work highlights the importance of considering population trajectories in addition to genetic diversity when assessing the genetics of populations for conservation and management purposes.


Assuntos
Baleia Franca , Variação Genética , Dinâmica Populacional , Animais , Regiões Árticas , Baleia Franca/genética , Canadá , Mudança Climática , Densidade Demográfica , Ecossistema , Caça
3.
J Hum Evol ; 196: 103590, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39357283

RESUMO

The Schöningen 13II-4 site is a marvel of Paleolithic archaeology. With the extraordinary preservation of complete wooden spears and butchered large mammal bones dating from the Middle Pleistocene, Schöningen maintains a prominent position in the halls of human origins worldwide. Here, we present the first analysis of the complete large mammal faunal assemblage from Schöningen 13II-4, drawing on multiple lines of zooarchaeological and taphonomic evidence to expose the full spectrum of hominin activities at the site-before, during, and after the hunt. Horse (Equus mosbachensis) remains dominate the assemblage and suggest a recurrent ambush hunting strategy along the margins of the Schöningen paleo-lake. In this regard, Schöningen 13II-4 provides the first undisputed evidence for hunting of a single prey species that can be studied from an in situ, open-air context. The Schöningen hominins likely relied on cooperative hunting strategy to target horse family groups, to the near exclusion of bachelor herds. Horse kills occurred during all seasons, implying a year-round presence of hominins on the Schöningen landscape. All portions of prey skeletons are represented in the assemblage, many complete and in semiarticulation, with little transport of skeletal parts away from the site. Butchery marks are abundant, and adult carcasses were processed more thoroughly than were juveniles. Numerous complete, unmodified bones indicated that lean meat and marrow were not always so highly prized, especially in events involving multiple kills when fat and animal hides may have received greater attention. The behaviors displayed at Schöningen continue to challenge our perceptions and models of past hominin lifeways, further cementing Schöningen's standing as the archetype for understanding hunting adaptations during the European Middle Pleistocene.


Assuntos
Arqueologia , Animais , Cavalos/anatomia & histologia , Caça , Alemanha , Hominidae/anatomia & histologia , Hominidae/fisiologia , Mamíferos , Fósseis/anatomia & histologia , Comportamento Predatório
4.
Sci Rep ; 14(1): 25290, 2024 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-39455743

RESUMO

Wind farms are still developing dynamically worldwide, with promising prospects for further growth. Therefore, the assessment of their impact on animals has been carried out. So far, few studies have been conducted on game mammals, and their results are divergent. Previous studies on the impact of wind farms on game species were typically based on regional research covering one or, at most, several wind farms. In this study, we aimed to verify the effect of wind farms on the density of game mammals through a large-scale analysis at the country level, using lowland Poland as an example. The study was based on hunting bag data from open-field hunting districts. It covered seven game species: roe deer (Capreolus capreolus), wild boar (Sus scrofa), red fox (Vulpes vulpes), raccoon dog (Nyctereutes procyonoides), European badger (Meles meles), European polecat (Mustela putorius), and European hare (Lepus europaeus). We used Corine Land Cover to account for differences in land cover and the area covered by wind farms in generalized linear mixed models. The study showed that in agricultural landscapes, mainly herbivorous species of game mammals were related to land cover types. These species tend to exhibit higher densities in agricultural areas containing more natural landscape features. Conversely, mesocarnivores are primarily driven by the abundance of prey with little to no observable effects from land cover types. Only roe deer and wild boar presented lower densities with an increase in the area covered by wind farms (for roe deer: estimate: - 0.05, 95% CI: - 0.1-0.0; for wild boar: estimate: - 0.03, 95% CI: - 0.11-0.05), while no effect was observed for mesocarnivores or European hare. The underlying reasons for these relationships remain unclear and require more specific studies. The uncertainty regarding the cause of the observed effects did not allow for a large-scale assessment of the impact of further wind energy development on the studied game mammals.


Assuntos
Mamíferos , Vento , Animais , Polônia , Animais Selvagens , Densidade Demográfica , Caça , Cervos/fisiologia , Sus scrofa , Conservação dos Recursos Naturais
6.
Conserv Biol ; 38(5): e14335, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248732

RESUMO

The burgeoning illegal trade in succulents in southern Africa presents a critical conservation and social development challenge. Drawing parallels with the trajectory of the response to rhinoceros poaching, we considered the consequences of conservation law enforcement measures, particularly the militarization of antipoaching efforts. The response to rhinoceros poaching not only resulted in so-called green militarization, but also led to extrajudicial killings, human rights abuses, and the disproportionate targeting of low-level poachers. The nature of wildlife trade prohibition is complex and often contested, and many actors operating in illegal wildlife trades dispute the label of illegal for socioeconomic, cultural, historical, or political reasons. This contestation is crucial when considering Indigenous cultural and medicinal values of succulents, with Indigenous Peoples and local communities questioning the criminalization of traditional plant harvesting practices. As the illegal trade in succulents continues to grow, it is imperative for conservationists to consider a nuanced approach. We call for a socioecological harm reduction approach that emphasizes community engagement, sustainable use, and codesigned interventions. Such an approach could help balance the scales of ecological conservation and human dignity in the face of growing wildlife trade challenges.


La necesidad de una estrategia socioecológica de reducción de daño para disminuir el mercado ilegal de fauna Resumen El emergente mercado ilegal de suculentas en el sur de África representa un reto importante para la conservación y el desarrollo social. Partimos de las similitudes con la trayectoria de la respuesta a la caza furtiva de rinocerontes para considerar las consecuencias de la aplicación de las leyes de conservación, en particular la militarización de los esfuerzos contra la caza furtiva. La respuesta a la caza furtiva no sólo derivó en la llamada militarización verde, sino también llevó a ejecuciones extrajudiciales, abuso de los derechos humanos y a la selección desproporcionada de cazadores de bajo nivel. La naturaleza de la prohibición del mercado de fauna es compleja y con frecuencia se impugna, y muchos actores que operan en los mercados ilegales disputan la etiqueta ilegal por razones socioeconómicas, culturales, históricas o políticas. Esta impugnación es crucial cuando consideramos los valores culturales y medicinales que los indígenas dan a las suculentas, sobre todo cuando los pueblos indígenas y las comunidades locales cuestionan la criminalización de las prácticas tradicionales de recolección de plantas. Conforme el mercado ilegal de suculentas sigue creciendo, es imperativo que los conservacionistas consideren una estrategia con matices. Pedimos una estrategia socioecológica de reducción de daños que resalte la participación comunitaria, el uso sustentable y las intervenciones con co­diseño. Dicha estrategia podría ayudar a equlibrar la balanza de la conservación ecológica y la dignidad humana de cara al incremento de retos en el mercado de fauna.


Assuntos
Animais Selvagens , Comércio , Conservação dos Recursos Naturais , Redução do Dano , Perissodáctilos , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Animais , Comércio/legislação & jurisprudência , Crime/prevenção & controle , África Austral , Humanos , Caça , Comércio de Vida Silvestre
7.
Conserv Biol ; 38(5): e14334, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248774

RESUMO

Globally, illegal sport hunting can threaten prey populations when unregulated. Due to its covert nature, illegal sport hunting poses challenges for data collection, hindering efforts to understand the full extent of its impacts. We gathered social media data to analyze patterns of illegal sport hunting and wildlife depletion across Brazil. We collected data for 2 years (2018-2020) across 5 Facebook groups containing posts depicting pictures of illegal sport hunting events of native fauna. We described and mapped these hunting events by detailing the number of hunters involved, the number of species, the mean body mass of individuals, and the number and biomass of individuals hunted per unit area, stratified by Brazilian biome. We also examined the effects of defaunation on hunting yield and composition via regression models, rank-abundance curves, and spatial interpolation. We detected 2046 illegal sport hunting posts portraying the hunting of 4658 animals (∼29 t of undressed meat) across all 27 states and 6 natural biomes of Brazil. Of 157 native species targeted by hunters, 19 are currently threatened with extinction. We estimated that 1414 hunters extracted 3251 kg/million km2. Some areas exhibited more pronounced wildlife depletion, in particular the Atlantic Forest and Caatinga biomes. In these areas, there was a shift from large mammals and reptiles to small birds as the main targeted taxa, and biomass extracted per hunting event and mean body mass across all taxonomic groups were lower than in other areas. Our results highlight that illegal sport hunting adds to the pressures of subsistence hunting and the wild meat trade on Brazil's wildlife populations. Enhanced surveillance efforts are needed to reduce illegal sport hunting levels and to develop well-managed sustainable sport hunting programs. These can support wildlife conservation and offer incentives for local communities to oversee designated sport hunting areas.


Exposición de la caza ilegal y la reducción de fauna en el país tropical más grande del mundo por medio de datos de las redes sociales Resumen En todo el mundo, la caza recreativa ilegal puede amenazar a las poblaciones de presas cuando no está regulada. Debido a su naturaleza encubierta, la caza recreativa ilegal plantea dificultades para la recopilación de datos, lo que dificulta la comprensión de su impacto. Recopilamos datos de redes sociales para analizar los patrones de caza recreativa ilegal y agotamiento de la vida silvestre en todo Brasil. Recopilamos datos durante 2 años (2018­2020) a través de cinco grupos de Facebook que contenían publicaciones que mostraban imágenes de eventos de caza recreativa ilegal de fauna nativa. Describimos y mapeamos estos eventos de caza detallando el número de cazadores involucrados, el número de especies, la masa corporal media de los individuos y el número y la biomasa de los individuos cazados por unidad de área, estratificados por bioma brasileño. También examinamos los efectos de la deforestación en el rendimiento y la composición de la caza mediante modelos de regresión, curvas de abundancia e interpolación espacial. Detectamos 2,046 puestos de caza recreativa ilegal que mostraban la caza de 4,658 animales (∼29 t de carne sin desollar) en los 27 estados y 6 biomas naturales de Brasil. De las 157 especies autóctonas objetivo de los cazadores, 18 están actualmente en peligro de extinción. Se calcula que 1,414 cazadores extrajeron 3,251 kg/millón de km2. Algunas zonas mostraron una defaunación más pronunciada, en particular los biomas de la Mata Atlántica y la Caatinga. En estas áreas, se produjo un cambio de grandes mamíferos y reptiles a pequeñas aves como principales taxones objetivo, y la biomasa extraída por evento de caza y la masa corporal media en todos los grupos taxonómicos fueron menores que en otras áreas. Nuestros resultados ponen de manifiesto que la caza recreativa ilegal se suma a las presiones de la caza de subsistencia y el comercio de carne salvaje sobre las poblaciones de fauna de Brasil. Es necesario intensificar los esfuerzos de vigilancia para reducir los niveles de caza recreativa ilegal y desarrollar programas de caza recreativa sostenibles y bien gestionados. Estos programas pueden contribuir a la conservación de la fauna y ofrecer incentivos a las comunidades locales para que supervisen las zonas designadas para la caza recreativa.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Caça , Mídias Sociais , Conservação dos Recursos Naturais/legislação & jurisprudência , Brasil , Animais , Esportes/legislação & jurisprudência , Humanos
8.
PeerJ ; 12: e18045, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39308819

RESUMO

Background: The expansion of human activities in their many forms increases the frequency, diversity, and scale of human-wildlife interactions. One such negative form is the expansion of road infrastructure, causing road kill and traffic-related noise as well as habitat loss and fragmentation. Even so, habitats around road infrastructure are attractive foraging areas that attract certain bird species. We assessed the impact of road infrastructure on the foraging strategies of the common buzzard Buteo buteo. Methods: Birds were observed during two winter seasons in two land-use types, along an expressway and an open agricultural landscape. Individual birds were tracked for a 10-min sequence as a separate sample was analysed. The material, covering 1,220 min along the expressway, and 1,100 min in the agricultural landscape, was collected. Results: Time spent by buzzards on medium-height sites was higher along the expressway than in farmland. Buzzards changed their hunting sites following the mean wind speed. Also, they more often changed their sites along the expressway than in farmland. The land-use types, snow cover, and the mean wind speed mediated the number of attacks on prey. These results illustrate the high plasticity of the buzzards' behaviour, which can adapt their hunting strategies to both foraging locations (expressway and farmland) and weather conditions. Roadsides along expressways are attractive foraging areas for this diurnal raptor, so reducing the risk of vehicle collisions with this and other birds of prey may require targeted planning efforts.


Assuntos
Falconiformes , Animais , Falconiformes/fisiologia , Caça , Ecossistema , Estações do Ano , Agricultura , Comportamento Predatório/fisiologia
9.
Nature ; 634(8034): 617-625, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232174

RESUMO

The adoption of agriculture triggered a rapid shift towards starch-rich diets in human populations1. Amylase genes facilitate starch digestion, and increased amylase copy number has been observed in some modern human populations with high-starch intake2, although evidence of recent selection is lacking3,4. Here, using 94 long-read haplotype-resolved assemblies and short-read data from approximately 5,600 contemporary and ancient humans, we resolve the diversity and evolutionary history of structural variation at the amylase locus. We find that amylase genes have higher copy numbers in agricultural populations than in fishing, hunting and pastoral populations. We identify 28 distinct amylase structural architectures and demonstrate that nearly identical structures have arisen recurrently on different haplotype backgrounds throughout recent human history. AMY1 and AMY2A genes each underwent multiple duplication/deletion events with mutation rates up to more than 10,000-fold the single-nucleotide polymorphism mutation rate, whereas AMY2B gene duplications share a single origin. Using a pangenome-based approach, we infer structural haplotypes across thousands of humans identifying extensively duplicated haplotypes at higher frequency in modern agricultural populations. Leveraging 533 ancient human genomes, we find that duplication-containing haplotypes (with more gene copies than the ancestral haplotype) have rapidly increased in frequency over the past 12,000 years in West Eurasians, suggestive of positive selection. Together, our study highlights the potential effects of the agricultural revolution on human genomes and the importance of structural variation in human adaptation.


Assuntos
Agricultura , Amilases , Evolução Molecular , Dosagem de Genes , Genoma Humano , Haplótipos , Seleção Genética , Humanos , Agricultura/história , Agricultura/estatística & dados numéricos , Amilases/genética , Amilases/química , Dosagem de Genes/genética , Duplicação Gênica/genética , Loci Gênicos/genética , Genoma Humano/genética , Haplótipos/genética , História Antiga , Taxa de Mutação , Polimorfismo de Nucleotídeo Único/genética , Caça/estatística & dados numéricos , Deleção de Genes , DNA Antigo/análise
10.
Proc Biol Sci ; 291(2031): 20240967, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39288802

RESUMO

The hypothesized main drivers of megafauna extinctions in the late Quaternary have wavered between over-exploitation by humans and environmental change, with recent investigations demonstrating more nuanced synergies between these drivers depending on taxon, spatial scale, and region. However, most studies still rely on comparing archaeologically based chronologies of timing of initial human arrival into naïve ecosystems and palaeontologically inferred dates of megafauna extinctions. Conclusions arising from comparing chronologies also depend on the reliability of dated evidence, dating uncertainties, and correcting for the low probability of preservation (Signor-Lipps effect). While some models have been developed to test the susceptibility of megafauna to theoretical offtake rates, none has explicitly linked human energetic needs, prey choice, and hunting efficiency to examine the plausibility of human-driven extinctions. Using the island of Cyprus in the terminal Pleistocene as an ideal test case because of its late human settlement (~14.2-13.2 ka), small area (~11 000 km2), and low megafauna diversity (2 species), we developed stochastic models of megafauna population dynamics, with offtake dictated by human energetic requirements, prey choice, and hunting-efficiency functions to test whether the human population at the end of the Pleistocene could have caused the extinction of dwarf hippopotamus (Phanourios minor) and dwarf elephants (Palaeoloxodon cypriotes). Our models reveal not only that the estimated human population sizes (n = 3000-7000) in Late Pleistocene Cyprus could have easily driven both species to extinction within < 1000 years, the model predictions match the observed, Signor-Lipps-corrected chronological sequence of megafauna extinctions inferred from the palaeontological record (P. minor at ~12-11.1 ka, followed by P. cypriotes at ~10.3-9.1 ka).


Assuntos
Extinção Biológica , Animais , Humanos , Chipre , Caça , Fósseis , Paleontologia
11.
PLoS One ; 19(8): e0307996, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39167742

RESUMO

Historical and ethnographic sources depict use of portable braced shaft weapons, or pikes, in megafauna hunting and defense during Late Holocene millennia in North and South America, Africa, Eurasia and Southeast Asia. Given the predominance of megafauna in Late Pleistocene North America during the centuries when Clovis points appeared and spread across much of the continent (13,050-12,650 cal BP), braced weapons may have been used in hunting of megaherbivores and defense against megacarnivores. Drawing from historical examples of pike use against lions, jaguars, boars, grizzlies, carabao and warhorses we consider the possibility of a fluted lithic pike. Associated osseous rods have been problematic as Clovis foreshafts due to the bevel angle and the apparent weakness of the splint haft when great strength is needed for deep penetration in megafauna hunting. However our review of Late Holocene pike use in megafauna encounters indicates the sharp tip becomes less important after hide or armor has been pierced because compression is sustained. Thus, foreshaft collapse after hide entry may not limit but rather increase the efficacy of the braced weapon. We conduct preliminary static experiments to model a fluted pike that adjusts during compression such that haft collapse and point detachment (when point jams on impact with bone) preserve the fluted biface, beveled rod and wooden mainshaft tip. In addition to Clovis point attributes and association with osseous rods, potential archaeological correlates of Clovis pike use include the high frequency of Clovis point isolates and concentrations of complete points with unbutchered mammoth remains at sites such as Naco in Arizona.


Assuntos
Armas , Animais , Armas/história , Lagomorpha/fisiologia , Arqueologia , Fósseis , Caça , História Antiga , Humanos
12.
PLoS One ; 19(8): e0308068, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39141605

RESUMO

In Africa, humans and large carnivores compete over access to resources, including prey. Disturbance by humans to kills made by carnivores, often for purposes of obtaining all or portions of the carcass, constitutes a form of human-wildlife conflict. However the occurrence of this practice, known as human kleptoparasitism, and its impact on carnivores has received little scientific attention. We obtained expert opinions from African lion researchers and stakeholders via a standardized questionnaire to characterize the geographic extent and frequency of human kleptoparasitism as it occurs in modern times. Our survey found modern human kleptoparasitism on kills made by lions, and possibly other large carnivores in Africa, to be geographically more widespread than previously reported. Meat lost to humans requires carnivores to hunt and kill additional prey thereby causing stress, increasing their energetic costs and risks of natural injury, and exposing them to risk of direct injury or death from human usurpers. Because of their conspicuous behaviors and tendency towards killing large-bodied prey, lions are particularly susceptible to humans detecting their kills. While human kleptoparasitism was geographically widespread, socio-economic factors influenced the frequency of occurrence. Prey type (wild game or domestic livestock) influenced human attitudes towards meat theft; ownership allows for legal recovery of livestock carcasses, while possessing wild game meat is mostly illegal and may incur penalties. Meat theft was associated with other illegal activities (i.e., illegal mining) and most prevalent among people of low income, including underpaid game scouts. Despite quantifiable costs to carnivores of human disturbance to their kills, the majority of experts surveyed reported a lack of knowledge on this practice. We propose that human disturbance at kills, especially loss of prey through human kleptoparasitism, constitutes an important anthropogenic threat that may seriously impact energy budgets of individual lions and other scavengers when meat and carcasses are removed from the ecosystem, and that the costs incurred by carnivores warrants further investigation.


Assuntos
Conservação dos Recursos Naturais , Leões , Carne , Comportamento Predatório , Animais , Humanos , Conservação dos Recursos Naturais/economia , África , Caça , Inquéritos e Questionários , Animais Selvagens
13.
Sci Rep ; 14(1): 19930, 2024 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-39198665

RESUMO

Human-induced disturbances of the environment are rapid and often unpredictable in space and time, exposing wildlife to strong selection pressure favouring plasticity in specific traits. Measuring wildlife behavioural plasticity in response to human-induced disturbances such as hunting pressures is crucial in understanding population expansion in the highly plastic wild boar species. We collected GPS-based movement data from 55 wild boars during drive hunts over three hunting seasons (2019-2022) in the Czech Republic and Sweden to identify behavioural plasticity in space use and movement strategies over a range of experienced hunting disturbances. Daily distance, daily range, and daily range overlap with hunting area were not affected by hunting intensity but were clearly related to wild boar hunting experience. On average, the post-hunt flight distance was 1.80 km, and the flight duration lasted 25.8 h until they returned to their previous ranging area. We detected no relationship in flight behaviour to hunting intensity or wild boar experience. Wild boar monitored in our study showed two behavioural responses to drive hunts, "remain" or "leave". Wild boars tended to "leave" more often with increasing hunting experience. Overall, this study highlights the behavioural plasticity of wild boar in response to drive hunts.


Assuntos
Comportamento Animal , Sus scrofa , Animais , Sus scrofa/fisiologia , República Tcheca , Comportamento Animal/fisiologia , Caça , Suécia , Humanos , Animais Selvagens/fisiologia , Voo Animal/fisiologia , Masculino
14.
Proc Natl Acad Sci U S A ; 121(34): e2405993121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39136992

RESUMO

Beluga whales play a critical role in the subsistence economies and cultural heritage of Indigenous communities across the Arctic, yet the effects of Indigenous hunting on beluga whales remain unknown. Here, we integrate paleogenomics, genetic simulations, and stable δ13C and δ15N isotope analysis to investigate 700 y of beluga subsistence hunting in the Mackenzie Delta area of northwestern Canada. Genetic identification of the zooarchaeological remains, which is based on radiocarbon dating, span three time periods (1290 to 1440 CE; 1450 to 1650 CE; 1800 to 1870 CE), indicates shifts across time in the sex ratio of the harvested belugas. The equal number of females and males harvested in 1450 to 1650 CE versus more males harvested in the two other time periods may reflect changes in hunting practices or temporal shifts in beluga availability. We find temporal shifts and sex-based differences in δ13C of the harvested belugas across time, suggesting historical adaptability in the foraging ecology of the whales. We uncovered distinct mitochondrial diversity unique to the Mackenzie Delta belugas, but found no changes in nuclear genomic diversity nor any substructuring across time. Our findings indicate the genomic stability and continuity of the Mackenzie Delta beluga population across the 700 y surveyed, indicating the impact of Inuvialuit subsistence harvests on the genetic diversity of contemporary beluga individuals has been negligible.


Assuntos
Beluga , Animais , Beluga/genética , Territórios do Noroeste , Feminino , Masculino , Caça , Isótopos de Nitrogênio/análise , Isótopos de Carbono/análise , DNA Mitocondrial/genética , Inuíte
15.
Environ Monit Assess ; 196(9): 862, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212756

RESUMO

Turtle species in the Family Podocnemididae, including the Colombian endemic and critically endangered Magdalena River Turtle Podocnemis lewyana, characteristically present low recapture rates that preclude estimation of population parameters using maximum likelihood modeling. In our 12-year monitoring project with this species, we evaluated changes in relative abundances, proportions of sex/size classes, and individual body sizes and body conditions in a population in four channels in the middle Magdalena River drainage. We also inspected for associations between trends in changes in these variables and differences in hunting pressure and habitat degradation. To inspect for temporal and spatial demographic dynamics, we estimated variation in relative abundances using the Catch Per Unit Effort index, the total number of turtles captured over an entire 5-day sampling period using ten baited funnel traps. Relative abundances and the proportions of sex/size classes were different between sites and years. We found a significant decline in the proportion of females and juveniles over time, along with evidence that the females still present were smaller in body size. Our results support the hypothesis that hunting eliminates adult females from these sites, perhaps also translating into a reduction in recruitment. The lack of evidence of generalized declines in body condition of all size classes suggests that habitat degradation might contribute less to the population declines in this region. Our results also illustrate that even when recapture rates are low, monitoring turtles via standardized trapping may yield insights into the population's conservation status that other relative abundance indices cannot.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Rios , Tartarugas , Animais , Caça , Feminino , Masculino , Monitoramento Ambiental/métodos , Dinâmica Populacional , Colômbia
17.
An Acad Bras Cienc ; 96(suppl 1): e20231185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109698

RESUMO

To address urban turtle sampling challenges, we presented Hookless fishing with clip, a cost-effective method for sampling this important group. Effectiveness, biases and potential advantages were analysed in comparison to two commonly used methods (funnel trap and hand capture). Fieldwork was conducted between August and November/2021 in four areas in Brazil, using the three methods simultaneously. A total of 195 turtles from four species (Phrynops geoffroanus, Hydromedusa tectifera, Trachemys dorbigni and T. scripta elegans) were captured. Funnel trap demonstrate a significantly higher capture than hand capture, while Hookless fishing showed no significant difference in captures compared to funnel trap. The highest catch per unit effort values were observed for the new method (0.37) and the funnel trap (0.34). Despite being widely used, funnel traps were the only method to exhibit male bias. Our findings revealed that Hookless fishing with clip exhibited remarkable capture efficiency, cost-effectiveness, and ease of transport and utilization; however, it requires operator presence. Nevertheless, the proposed method, both as the primary or auxiliary approach, appears efficient in enhancing captures and reducing costs and risks. This innovative method has the potential to assist researchers studying omnivorous and carnivores freshwater turtles in environments worldwide, especially in human settlements.


Assuntos
Tartarugas , Animais , Tartarugas/classificação , Brasil , Masculino , Feminino , Caça , Análise Custo-Benefício
19.
Nature ; 630(8017): 666-670, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839951

RESUMO

Resolving the timescale of human activity in the Palaeolithic Age is one of the most challenging problems in prehistoric archaeology. The duration and frequency of hunter-gatherer camps reflect key aspects of social life and human-environment interactions. However, the time dimension of Palaeolithic contexts is generally inaccurately reconstructed because of the limitations of dating techniques1, the impact of disturbing agents on sedimentary deposits2 and the palimpsest effect3,4. Here we report high-resolution time differences between six Middle Palaeolithic hearths from El Salt Unit X (Spain) obtained through archaeomagnetic and archaeostratigraphic analyses. The set of hearths covers at least around 200-240 years with 99% probability, having decade- and century-long intervals between the different hearths. Our results provide a quantitative estimate of the time framework for the human occupation events included in the studied sequence. This is a step forward in Palaeolithic archaeology, a discipline in which human behaviour is usually approached from a temporal scale typical of geological processes, whereas significant change may happen at the smaller scales of human generations. Here we reach a timescale close to a human lifespan.


Assuntos
Arqueologia , Sedimentos Geológicos , Atividades Humanas , Arqueologia/métodos , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , História Antiga , Caça/história , Espanha , Fatores de Tempo , Atividades Humanas/história , Incêndios/história , Culinária/história
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