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Vultures in Africa are being poisoned deliberately by poachers to prevent the birds alerting authorities to the poachers’ illegal activities, or for harvesting and sale of body parts for use in witchcraft. Hundreds of vultures can be killed at a single poisoned elephant Loxodonta africana carcass, and although field staff trained in poison response activities can limit the damage, mortalities remain numerous. We used the population viability analysis programme VORTEX to simulate seven 100-year-long scenarios investigating various rates of poisoning mortalities and the remedial effects of poison response activities on a population of Critically Endangered white-backed vultures Gyps africanus breeding in Kruger National Park, South Africa. In six scenarios the population declined (λ < 1); in three scenarios the population remained extant over the 100-year simulations but declined by 60–90% from a starting size of 2,400 individuals. In two scenarios one poisoned elephant carcass left untreated and causing the greatest number of vulture deaths was modelled as a catastrophic event with a 50% probability of annual occurrence, which resulted in a 100% probability of population extinction, with a mean time to extinction of 55–62 years. Effective poison response activities were modelled as a 70% reduction of mortality at each poisoned elephant carcass and resulted in population persistence after 100 years but with a c. 90% reduction in size (final n = 205). We highlight that although poison response activities will not prevent poisoning from occurring, they form an essential part of wider conservation actions designed to prevent local extinctions of vultures or other vulnerable species.

The prosperity and well-being of human societies relies on healthy ecosystems and the services they provide. However, the biodiversity crisis is undermining ecosystems services and functions. Vultures are among the most imperiled taxonomic groups on Earth, yet they have a fundamental ecosystem function. These obligate scavengers rapidly consume large amounts of carrion and human waste, a service that may aid in both disease prevention and control of mammalian scavengers, including feral dogs, which in turn threaten humans. We combined information about the distribution of all 15 vulture species found in Europe, Asia, and Africa with their threats and used detailed expert knowledge on threat intensity to prioritize critical areas for conserving vultures in Africa and Eurasia. Threats we identified included poisoning, mortality due to collision with wind energy infrastructures, and other anthropogenic activities related to human land use and influence. Areas important for vulture conservation were concentrated in southern and eastern Africa, South Asia, and the Iberian Peninsula, and over 80% of these areas were unprotected. Some vulture species required larger areas for protection than others. Finally, countries that had the largest share of all identified important priority areas for vulture conservation were those with the largest expenditures related to rabies burden (e.g., India, China, and Myanmar). Vulture populations have declined markedly in most of these countries. Restoring healthy vulture populations through targeted actions in the priority areas we identified may help restore the ecosystem services vultures provide, including sanitation and potentially prevention of diseases, such as rabies, a heavy burden afflicting fragile societies. Our findings may guide stakeholders to prioritize actions where they are needed most in order to achieve international goals for biodiversity conservation and sustainable development. La prosperidad y el bienestar de la sociedad humana dependen de ecosistemas sanos y de los servicios ambientales que éstosproporcionan. Sin embargo, la crisisde biodiversidadestá afectandoa los servicios ambientales y sus funciones. Los buitres se encuentran entre los grupos taxonómicos con mayor amenaza sobre el planeta, a pesar de tener una función fundamental en los ecosistemas. Estos carroñeros obligados consumen rápidamente grandes cantidades de carroña y desechos humanos, un servicio que puede ayudar en la prevención de enfermedades y en el control de mamíferos carroñeros, incluyendo a los perros ferales, los cuales pueden ser un peligro para los humanos. Combinamos la información sobre la distribución de las 15 especies de buitres en Europa, Asia y África con las amenazas que presentan y usamos el conocimiento detallado de expertos sobre la intensidad de las amenazas para priorizar las áreas críticas para la conservación de buitres en África y en Eurasia. Las amenazas que identificamos incluyeron el envenenamiento, la mortalidad por colisiones con infraestructura eólica y otras actividades antropogénicas relacionadas con el uso de suelo y la influencia humana. Las áreas importantes para la conservación de buitres estuvieron concentradas en el sur y el este de África, el sur de Asia y la Península Ibérica, y más del 80% de estas áreas no contaban con protección. Algunas especies de buitres requirieron áreas más grandes para su protección que otras especies. Finalmente, los países que tuvieron la mayor porción de todas las áreas prioritarias importantes e identificadas para la conservación de buitres también fueron aquellos con los mayores gastos relacionados con la carga de la rabia (por ejemplo, India, China y Myanmar). Las poblaciones de buitres han declinado marcadamente en la mayoría de estos países. La restauración de poblaciones sanas de buitres por medio de acciones enfocadas en las áreas prioritarias que identificamos puede ayudar a restaurar los servicios ambientales que proporcionan los buitres, incluyendo el saneamiento y la prevención potencial de enfermedades, como la rabia, una carga pesada que aflige a las sociedades frágiles. Nuestros resultados pueden guiar a los interesados hacia la priorización de acciones en donde más se necesitan para poder alcanzar los objetivos internacionales para la conservación de la biodiversidad y el desarrollo sustentable. 人类社会的繁荣昌盛依赖于健康的生态系统及其所提供的服务。然而，生物多祥性危机芷在破坏生态系 统的服务和功能。秃鹰是地球上最濒危的类群之一，而它们却能提供基础的生态系统功能。它们作为专性食腐 动物可以快速消耗大量腐肉及人类废弃物，提供的生态系统服务有助于预防疾病，以及控制哺乳类食腐动物，如 会对人类造成威胁的野狗。我们将欧洲、亚洲和非洲的全部+ 五种秃鹰的分布信息与其面临的威胁相结合，利 用详细的关于威胁强度的专业知识, 确定了非洲及欧亚关键的秃鹰保护优先地区。秃鹰面临的威胁包括中毒、 撞击风能设施导致的死亡，以及与人类土地利用和影响有关的其它人类活动。秃鹰的重点保护区域集中在非洲 南部和东部、南非和利比亚半岛，这些地区超过80%的土地没有得到保护。另外，秃鹰中某些物种相比之下需 要更大区域进行保护。我们还发现,秃鹰的重要优先保护区域占比最大的国家同时也是那呰在狂犬病上的支出 最高的国家(如印度、中国、缅甸)，而其中大多数国家的秃鹰种群数量已经明显下降。通过在我们确定的优先 保护区域采取有针对性的行动来恢复健康的秃鹰种群，可能有助于恢复秃鹰提供的生态系统服务，包括环境卫 生和预防潜在疾病，比如狂犬病这种沉重的社会负担。我们的研究成果可以指导利益相关者在需求最迫切的地 方优先采取行动，以实现生物多祥性保护和可持续发展的国际目标。

Intra‐Africa movements of most African migratory birds remain an enigma. We describe the migrations of Wahlberg's eagle Hieraaetus wahlbergi using GPS‐GSM transmitters on adult eagles in their South African (n = 3) and Kenyan (n = 7) breeding areas between 2018 and 2022. The dataset included 57 migratory tracks, 29 post‐breeding and 28 pre‐breeding. We found long‐distance migrants (LDMs; from South Africa) and short‐distance migrants (SDMs; from Kenya) using common non‐breeding areas centered in the Sudans and Central African Republic. The timing of annual phases was similar, but LDMs departed on their pre‐breeding migration on average later than SDMs (13 August versus 31 July) and arrived later on their breeding grounds (13 September versus 10 August). Conversely, the average departure date on the post‐breeding migration was 4 April for SDM and 23 March for LDMs. LDMs spent significantly less time of the year than SDMs on breeding grounds (44 versus 57%), and slightly but not significantly more time (40 versus 38%) on non‐breeding areas. The post‐breeding migration distance was on average 3413.9 ± 170.9 km for LDMs and 491.9 ± 158.5 km for SDMs. At non‐breeding areas, LDMs reached more northerly latitudes than SDMs, increasing the pre‐breeding migration distance to 4495.9 ± 372.5 km for LDMs versus 1701.9 ± 167.3 for SDMs. Daily flight distances back to the breeding areas averaged 153.4 ± 130.3 km for LDMs and 167.4 ± 122.3 km for SDMs and to non‐breeding areas were shorter for SDMs (124.8 ± 113.0 km) than LDMs (178.0 ± 134.4 km). Migration speed was similar across populations and for pre‐ and post‐breeding migrations. LDMs used more stopover days than SDMs. We conclude that Wahlberg's eagles from different parts of Africa have adapted their migration to differences in timing of the breeding season, distance of travel, and resources in the landscapes encountered during migration.

Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30‐year Pan‐African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, economic, and human costs are already documented. Populations of eight species we assessed had declined by an average of 62%; seven had declined at a rate of 80% or more over three generations. Of these, at least six appear to qualify for uplisting to Critically Endangered. Africa's vultures are facing a range of specific threats, the most significant of which are poisoning and trade in traditional medicines, which together accounted for 90% of reported deaths. We recommend that national governments urgently enact and enforce legislation to strictly regulate the sale and use of pesticides and poisons, to eliminate the illegal trade in vulture body parts, as food or medicine, and to minimize mortality caused by power lines and wind turbines.

Recently developed capture-mark-recapture methods allow us to account for capture heterogeneity among individuals in the form of discrete mixtures and continuous individual random effects. In this article, we used simulations and two case studies to evaluate the effectiveness of continuously distributed individual random effects at removing potential bias due to capture heterogeneity, and to evaluate in what situation the added complexity of these models is justified. Simulations and case studies showed that ignoring individual capture heterogeneity generally led to a small negative bias in survival estimates and that individual random effects effectively removed this bias. As expected, accounting for capture heterogeneity also led to slightly less precise survival estimates. Our case studies also showed that accounting for capture heterogeneity increased in importance towards the end of study. Though ignoring capture heterogeneity led to a small bias in survival estimates, such bias may greatly impact management decisions. We advocate reducing potential heterogeneity at the sampling design stage. Where this is insufficient, we recommend modelling individual capture heterogeneity in situations such as when a large proportion of the individuals has a low detection probability (e.g. in the presence of floaters) and situations where the most recent survival estimates are of great interest (e.g. in applied conservation).

Understanding the ranging behaviours of species can be helpful in effective conservation planning. However, for many species that are rare, occur at low densities, or occupy challenging environments, this information is often lacking. The Martial Eagle (Polemaetus bellicosus) is a low density apex predator declining in both non-protected and protected areas in southern Africa, and little is known about its ranging behaviour. We use GPS tags fitted to Martial Eagles (n = 8) in Kruger National Park (KNP), South Africa to describe their ranging behaviour and habitat preference. This represents the first time that such movements have been quantified in adult Martial Eagles. Territorial eagles (n = 6) held home ranges averaging ca. 108 km2. Home range estimates were similar to expectations based on inter-nest distances, and these large home range sizes could constrain the carrying capacity of even the largest conservation areas. Two tagged individuals classed as adults on plumage apparently did not hold a territory, and accordingly ranged more widely (ca. 44,000 km2), and beyond KNP boundaries as floaters. Another two territorial individuals abandoned their territories and joined the 'floater' population, and so ranged widely after leaving their territories. These unexpected movements after territory abandonment could indicate underlying environmental degradation. Relatively high mortality of these wide-ranging 'floaters' due to anthropogenic causes (three of four) raises further concerns for the species' persistence. Habitat preference models suggested Martial Eagles used areas preferentially that were closer to rivers, had higher tree cover, and were classed as dense bush rather than open bush or grassland. These results can be used by conservation managers to help guide actions to preserve breeding Martial Eagles at an appropriate spatial scale.

Landau and Lifshitz developed their phenomenological equation for the magnetisation dynamics in ferromagnetic solids almost a century ago. At any specific time and position within the solid, the equation describes the rotations of the magnetisation vector under the influence of the effective magnetic field, i.e. the field ‘felt’ by the magnetisation. The effective field may include, for example, an applied (external) magnetic field as well as internal contributions from the exchange interaction and anisotropy. In 1951 the form of the damping term was modified by Gilbert, and the resulting (mathematically equivalent) equation became known as the Landau-Lifshitz-Gilbert equation. With the rapid increase in computational speed and accessibility during subsequent years, and the growth of computational solid state physics and material science, numerical simulations based on the Landau-Lifshitz-Gilbert equation have greatly assisted with the development of certain technological applications, e.g. hard disk drives. In the present work we review some of the challenges associated with solving this important equation, numerically. In particular, we address the challenge of accurately conserving the magnitude of the magnetisation vector, . Usually, if the equation is solved in Cartesian coordinates via an explicit numerical method, m grows or contracts linearly in proportion to the integration time. Here, we show that a new phenomenological term, in the normal form of the supercritical pitchfork bifurcation, can be added to the LLG equation to conserve m numerically, without otherwise affecting the dynamics of the original equation. The additional term stabilises the numerical solution by attracting it to the stable fixed point at . Numerical results from seven different solvers are compared to evaluate the effects and efficiency of the additional term. We find that it permits the use of standard, explicit solvers, such as the classic forth-order Runge-Kutta method, to solve the LLG equation more efficiently than pseudo-symplectic or implicit methods, while conserving m to the same accuracy. A Python 3 implementation of the method is provided to solve and compare the MAG standard problem #4. For this problem the method provides a somewhat faster solution which is of comparable accuracy to other micromagnetic simulation software.

The conversion of natural habitats to farmland is a major cause of biodiversity loss and poses the greatest extinction risk to birds worldwide. Tropical raptors are of particular concern, being relatively slow-breeding apex predators and scavengers, whose disappearance can trigger extensive cascading effects. Many of Africa’s raptors are at considerable risk from habitat conversion, prey-base depletion and persecution, driven principally by human population expansion. Here we describe multiregional trends among 42 African raptor species, 88% of which have declined over a ca. 20–40-yr period, with 69% exceeding the International Union for Conservation of Nature criteria classifying species at risk of extinction. Large raptors had experienced significantly steeper declines than smaller species, and this disparity was more pronounced on unprotected land. Declines were greater in West Africa than elsewhere, and more than twice as severe outside of protected areas (PAs) than within. Worryingly, species suffering the steepest declines had become significantly more dependent on PAs, demonstrating the importance of expanding conservation areas to cover 30% of land by 2030—a key target agreed at the UN Convention on Biological Diversity COP15. Our findings also highlight the significance of a recent African-led proposal to strengthen PA management—initiatives considered fundamental to safeguarding global biodiversity, ecosystem functioning and climate resilience. A compilation of survey data from pre- and post-2000 for 42 raptor species across parts of West, Central, East and southern Africa shows 88% of species in population decline and reveals trends across regions, protected areas and species size.

Four species of African vultures have been recategorized as Critically Endangered, and two as Endangered, on the IUCN Red List. Their declining status is attributed partly to the impacts of widespread poisoning. Prior to 2012 poisoning of vultures was mostly associated with illegal predator control by livestock farmers, in which vultures were typically unintended victims. More recently, ivory poachers have been using poisons to kill elephants Loxodonta africana or to contaminate their carcasses specifically to eliminate vultures, whose overhead circling might otherwise reveal the poachers’ presence. Between 2012 and 2014 we recorded 11 poaching-related incidents in seven African countries, in which 155 elephants and 2,044 vultures were killed. In at least two incidents the harvesting of vulture body parts (for fetish) may have provided an additional motive. We show that vulture mortality associated with ivory poaching has increased more rapidly than that associated with other poisoning incidents, and now accounts for one-third of all vulture poisonings recorded since 1970. This recent surge in the illegal use of poisons exposes weaknesses in the regulations, for which we propose measures aimed primarily at retail controls. However, because ivory poachers already operate outside any legal framework, African governments require international support in applying more punitive sentencing against mass wildlife poisoning.