Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 467
Filtrar
1.
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
2.
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
4.
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
5.
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
7.
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
8.
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
9.
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
11.
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
12.
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
13.
PLoS One ; 19(6): e0301487, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865308

RESUMO

Management of wolves is controversial in many jurisdictions where wolves live, which underscores the importance of rigor, transparency, and reproducibility when evaluating outcomes of management actions. Treves and Louchouarn 2022 (hereafter TL) predicted outcomes for various fall 2021 hunting scenarios following Wisconsin's judicially mandated hunting and trapping season in spring 2021, and concluded that even a zero harvest scenario could result in the wolf population declining below the population goal of 350 wolves specified in the 1999 Wisconsin wolf management plan. TL further concluded that with a fall harvest of > 16 wolves there was a "better than average possibility" that the wolf population size would decline below that 350-wolf threshold. We show that these conclusions are incorrect and that they resulted from mathematical errors and selected parameterizations that were consistently biased in the direction that maximized mortality and minimized reproduction (i.e., positively biased adult mortality, negatively biased pup survival, further halving pup survival to November, negatively biased number of breeding packs, and counting harvested wolves twice among the dead). These errors systematically exaggerated declines in predicted population size and resulted in erroneous conclusions that were not based on the best available or unbiased science. Corrected mathematical calculations and more rigorous parameterization resulted in predicted outcomes for the zero harvest scenario that more closely coincided with the empirical population estimates in 2022 following a judicially prevented fall hunt in 2021. Only in scenarios with simulated harvest of 300 or more wolves did probability of crossing the 350-wolf population threshold exceed zero. TL suggested that proponents of some policy positions bear a greater burden of proof than proponents of other positions to show that "their estimates are accurate, precise, and reproducible". In their analysis, TL failed to meet this standard that they demanded of others.


Assuntos
Lobos , Animais , Incerteza , Wisconsin , Caça , Conservação dos Recursos Naturais/métodos , Densidade Demográfica , Dinâmica Populacional
15.
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
16.
Sci Total Environ ; 935: 173460, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38788939

RESUMO

Reduction of conflicts arising from human-wildlife interactions is necessary for coexistence. Collisions between animals and automobiles cost the world's economy billions of dollars, and wildlife management agencies often are responsible for reducing wildlife-vehicle collisions. But wildlife agencies have few proven options for reducing wildlife-vehicle collisions that are effective and financially feasible at large spatiotemporal scales germane to management. Recreational hunting by humans is a primary population management tool available for use with abundant wild ungulates that often collide with automobiles. Therefore, we tested how well policies designed to increase human hunting of deer (longer hunting seasons and increased harvest limits) reduced collisions between white-tailed deer and automobiles along 618 km of high-risk roadways in Indiana, USA. We used a 20-y dataset that compiled >300,000 deer-vehicle collisions. Targeted recreational hunting decreased deer-vehicle collisions by 21.12 % and saved society up to $653,756 (95 % CIs = $286,063-$1,154,118) in economic damages from 2018 to 2022. Potential savings was up to $1,265,694 (95 % CIs = $579,108-$2,402,813) during the same 5-y span if relaxed hunting regulations occurred along all high-risk roadways. Moreover, license sales from targeted hunting generated $206,268 in revenue for wildlife management. Targeted hunting is likely effective in other systems where ungulate-vehicle collisions are prevalent, as behavioral changes in response to human hunting has been documented in many ungulate species across several continents. Our methods are attractive for management agencies with limited funds, as relaxed hunting regulations are relatively inexpensive to implement and may generate substantial additional revenue.


Assuntos
Acidentes de Trânsito , Conservação dos Recursos Naturais , Cervos , Caça , Animais , Conservação dos Recursos Naturais/métodos , Acidentes de Trânsito/prevenção & controle , Indiana , Recreação , Animais Selvagens , Humanos
17.
Ambio ; 53(9): 1336-1354, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38727940

RESUMO

A full-life cycle approach is a tenet of migratory species conservation, yet the degree to which this is achieved remains largely unassessed. This knowledge gap can be addressed using the concept of social-ecological fit, understood as the match between governance and ecological dimensions. Here, we assess the social-ecological fit for conserving migratory shorebirds in the Asia-Pacific, focusing on habitat loss and hunting. We identify the governance architectures for addressing these two threats and then assess the coordinating capacity of each architecture, measure institutional coverage for each species across their range, and determine the degree of institutional connectivity along their migratory network. We find that social-ecological fit is higher for the governance of habitat designation than for hunting management, with implications for governance practice. Analyses of social-ecological fit thus provide critical insights on the potential effectiveness of governance and therefore are a useful first step for migratory species conservation.


Assuntos
Migração Animal , Aves , Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/métodos , Ásia , Caça , Oceano Pacífico
18.
Sci Adv ; 10(20): eadj7132, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38748803

RESUMO

Many large terrestrial mammalian predators use energy-intensive, high-risk, high-gain strategies to pursue large, high-quality prey. However, similar-sized marine mammal predators with even higher field metabolic rates (FMRs) consistently target prey three to six orders of magnitude smaller than themselves. Here, we address the question of how these active and expensive marine mammal predators can gain sufficient energy from consistently targeting small prey during breath-hold dives. Using harbor porpoises as model organisms, we show that hunting small aquatic prey is energetically cheap (<20% increase in FMR) for these marine predators, but it requires them to spend a large proportion (>60%) of time foraging. We conclude that this grazing foraging strategy on small prey is viable for marine mammal predators despite their high FMR because they can hunt near continuously at low marginal expense. Consequently, cessation of foraging due to human disturbance comes at a high cost, as porpoises must maintain their high thermoregulation costs with a reduced energy intake.


Assuntos
Comportamento Predatório , Animais , Comportamento Predatório/fisiologia , Metabolismo Energético , Caça , Mamíferos/fisiologia , Organismos Aquáticos/fisiologia , Phocoena/fisiologia
19.
Sci Total Environ ; 940: 173463, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-38802001

RESUMO

Wild ungulates are expanding in range and number worldwide leading to an urgent need to manage their populations to minimize conflicts and promote coexistence with humans. In the metropolitan area of Barcelona (MAB), wild boar is the main wildlife species causing a nuisance, from traffic accidents to health risks. Selective harvesting of specific sex and age classes and reducing anthropogenic food resources would be the most efficient approach to dealing with overpopulation. Nonetheless, there is a gap in knowledge regarding the age and sex selectivity of the capture methods currently applied in the MAB for wild boar population control. Thus, this study aimed to evaluate the performance and age and sex bias of different hunting and capture methods and the seasonal patterns in their performance (number of captured individuals per event). From February 2014 to August 2022, 1454 wild boars were captured in the MAB using drop net, teleanaesthesia, cage traps, night stalks, and drive hunting. We applied generalized linear models (GLM) to compare the performance of these methods for the total number of wild boars, the wild boars belonging to each age category (i.e., adult, yearling, and juvenile), and for each season. The studied capture methods showed age-class bias and sex bias in adults (>2 years). Drive hunting and drop net removed mainly adult females and yearlings (1-2 years), with drive hunting having the highest performance for adult males. Instead, cage traps and drop net were the best methods to capture juveniles (<1 year). Overall, global performance was higher in summer, decreasingly followed by autumn and spring, winter being the worst performing season. Wildlife managers and researchers should consider the different performance and sex and age bias of each hunting and capture method, as well as the associated public cost, to improve efficiency and achieve the best results in wild boar population management.


Assuntos
Caça , Sus scrofa , Animais , Espanha , Masculino , Feminino , Conservação dos Recursos Naturais/métodos , Estações do Ano , Animais Selvagens
20.
PLoS One ; 19(4): e0282374, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568901

RESUMO

The waters around the Galápagos Marine Reserve (GMR) are important fishing grounds for authorized artisanal vessels fishing within the reserve as well as for national and foreign industrial fleets operating in the wider Ecuadorian Insular Exclusive Economic Zone (IEEZ). Although it was not originally designed for fisheries management, Automatic Identification System (AIS) data provides useful, open access, near real-time and high-resolution information that allows for increased monitoring, particularly around Marine Protected Areas (MPAs) and in Areas Beyond National Jurisdiction. This study uses AIS data provided by Global Fishing Watch to assess the spatial distribution and seasonal dynamics of fishing effort by vessel flag within the GMR and the IEEZ from 2012 to 2021. Based on kernel density estimation analysis, we determinate the core-use areas (50%) and spatial extent (95%) of fishing activities by fleets (Ecuadorian and foreign), gear types and seasons (warm, from December to May; and cold, from June to November). Our results show that the Ecuadorian fleet recorded the most observed fishing hours in the study area, with 32,829 hours in the IEEZ and 20,816 hours within the GMR. The foreign flags with the most observed fishing hours in the IEEZ were Panama (3,245 hours) and Nicaragua (2,468.5 hours), while in the GMR were the 'Unknown flag' (4,991.4 hours) and Panama (133.7 hours). Vessels fished employing different fishing gears, but the waters of the GMR and IEEZ were mostly targeted by tuna purse-seiners and drifting longlines. The spatial distribution of the fishing effort exhibits marked seasonal variability, likely influenced by seasonal migrations of target species such as tunas (e.g., Thunnus albacares, T. obesus and Katsuwonus pelamis), marlins (e.g., Makaira nigricans) and sharks (e.g., Alopias pelagicus). The collection and use of this type of spatial and seasonal information is an essential step to understand the dynamics of fishing activities in national waters and improve fisheries management, particularly in less studied areas and fisheries.


Assuntos
Caça , Tubarões , Animais , Estações do Ano , Atum , Pesqueiros , Conservação dos Recursos Naturais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...