African Rhinoceros population rose by 5.2% in 2022 despite ongoing poaching.

The population of Rhinoceros across Africa rose by 5.2% during 2022, with 23 290 Animals at the end of the year., according to a press release issued by the International Union for the Conservation of Nature on 21 September 2023 This is despite ongoing poaching in many countries, with 561 Rhinoceros known to have been killed by poachers in 2022. South Africa has the highest population of Rhinoceros on the continent, but also the highest rate of poaching, with 448 Animals killed in 2022, slightly down on 2021, when 451 Rhinoceros were killed by poachers in South Africa. In Namibia 93 Rhinoceros are known to have been killed by poachers in 2022, a sharp rise on 2021, when only 47 were lost in this way. In Kenya a single Rhinoceros was lost to poachers in 2022, down from six in 2021. 

A Black Rhinoceros, Diceros bicornis, one of two species of Rhinoceros found in Africa. Steve Garvie/International Union for the Conservation of Nature.

Both species of African Rhinoceros have seen a population increase, with a combination of protection and biological management initiatives seeing the population of Black Rhinoceros, Diceros bicornis, increase by 4/2% to 6487, and the population of White Rhinoceros, Ceratotherium simum, increasing by 5.6% to 16 803. Notably, this is the first increase in white rhino numbers since 2012.

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A project to preserve Praia Melão, the largest Sugar mill and estate in São Tomé.

In the sixteenth century the island of São Tomé became a major hub in Portuguese trade between Europe and the Americas. However, the island was seen as dangerous and remote, with few people volunteering to go there. Instead, the island was forcibly settled with convicts, Jews expelled from Portugal, and slaves taken from the African coast. The island is thought to have played a key role in the development of the plantation slavery system which then spread to the Caribbean and North and South America, but has, to date, been the subject of little direct study.

In a paper published in the journal Antiquity on 14 August 2023, Dores Cruz of the University of Cologne, Larissa Thomas of Environmental Resources Management, and Nazaré Ceita of the University of São Tomé e Príncipe, discuss a project to preserve t the site of Praia Melão, the largest sugar mill and estate on the island, which was active from the sixteenth to the nineteenth centuries, and the first site to be investigated by archaeologists on São Tomé. 

The islands of São Tomé and Príncipe lie in the Gulf of Guinea off the west coast of Africa, and were claimed by Portugal in the late fifteenth century, with São Tomé. quickly becoming one of the first European-controlled ports in Africa, specialising in the extractive trade in slaves and gold, along with Elmina on the coast of what is now Ghana. The island has a tropical climate and an abundant supply of both fresh water and timber, and was recognised as a potential location for Sugarcane plantations as early as 1485, with the first cultivation of the crop recorded in 1506. By 1517 Sugar cultivation was growing and successful industry, with two Sugar mills in operation and plans to build ten more. Sugar cultivation is a labour intensive process, and the industry quickly became dependant on the importation of large numbers of slaves from Africa, principally from Benin in modern Nigeria and Kongo, which incorporated parts of the modern coasts of Angola, Democratic Republic of Congo, Republic of Congo, and Gabon. By the 1530s São Tomé had become the world's largest producer of Sugar, surpassing the island of Madeira where a more traditional style of cultivation was practiced, and becoming the first economy to be based upon the slavery and monoculture model, which was then exported to the new world. However, this economic dominance was short-lived, and by the beginning of the seventeenth century São Tomé had been surpassed as the largest producer of Sugar by Brazil. Many of the successful plantation owners from São Tomé relocated to the New World, and the island's economy became dependant on the export of slaves for plantations elsewhere.

Praia Melão: location maps (Gulf of Guinea) and site location. Cruz et al. (2023).

The interior of São Tomé is mountainous and heavily forested, which restricted early settlement to the coastal plains on the north and northeast of the island, where elevations are typically below 200 m. On these plains, the forests were largely cleared, to form large estates for the growing of Sugarcane, with mills being established by rivers and streams. The only known surviving estate house and mill from this period is at Praia Melão, which dates back to at least the sixteenth century, when it was recognises as the estate on the island. An archaeological survey of the site in 2020 established the importance of the site, and a heritage program has been developed by the University of São Tomé e Príncipe, which aims to include a field school, survey and excavation.

Estate house and sugar mill (view from southeast corner). Dores Cruz in Cruz et al. (2023).

The mill and estate house form a single large stone building, south of the village of Praia Melão by the Ribeiro Manuel Jorge, which flows eastwards to the Gulf of Guinea. The building appears to have been altered and probably expanded more than once during its long usage. Its general style is typical of Portuguese buildings of the period, including clay roof styles. The mill was powered by a mill race which channelled water from the river. Preliminary excavation work at the side has yielded s fragments of sugar moulds and the stone base of a press.

The building is a two-storey structure measuring 23 m x 16 m, subdivided into three large rooms on both floors. The largest room measures 17 m v 8.5 m and is adjacent to the retaining wall that supported the mill race, and housed the hydraulic mill or mills. The room next to this appears to have been used for sugar-boiling, and has scorched walls, presumably from the fires upon which the sugar was boiled. The upper story of the building has partially collapsed, but appears to have held living quarters for the mill owners, with stuccoed walls and wall cabinets, balconies, and windows that allowed surveillance of the working areas. The walls of the lower story are roughly finished and graffitied in places, largely with religious symbols and lettering. No kitchen has been identified, but an outside cooking area would not have been unusual for a Portuguese structure of the period.

Plan of the two floors (A) & (B) and elevation of southwest wall (C). Anna Krahl in Cruz et al. (2023).

Preliminary investigations at the site recovered numerous ceramic objects littering the site, mostly Sugar moulds, which have also been embedded in refurbished walls. X-ray fluorescence analysis of fragments of three moulds showed that they appear to have had a common origin to similar moulds from Madeira, which are known to have been produced in Aveiro, Portugal, which was a major centre for the exportation of ceramics for both domestic and industrial purposes.

Access to upper floor and graffiti. Lower level shows evidence of scorching. Dores Cruz in Cruz et al. (2023).

The building is thought to have been used for about 400 years after the decline of the Sugar industry on São Tomé, with Sugar production being surplanted by that of alcohol and then Cassava flower. Praia Melão is well documented in written histories of São Tomé, as well as the oral traditions of the island. Despite this, local communities seemed unaware of the significance of the site, even though it is located on a well-used footpath. This lack of awareness, combined with the tropical climate and encroaching forest vegetation, makes it likely that the site would disappear soon without active preservation.

Architectonic reconstruction. Luís Branco in Cruz et al. (2023).

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Comet C/2023 H2 (Lemmon) approaches perihelion.

Comet C/2023 H2 (Lemmon) will reach its perihelion (the closest point on its orbit to the Sun) on Sunday 29 October 2023, when it will be approximately 0.89 AU from the Sun (i.e. 89% of the distance from the Sun to the planet Earth, or 133 142 000 km). At this time the comet will be 0.49 AU from the Earth, in the constellation of Canes Venatici, having a magnitude of 7.1, making it visible from the Northern Hemisphere with a good pair of binoculars or small telescope.

C/2023 H2 (Lemmon) (green object at centre of picture) observed from Lleida in Spain on 23 September 2023. Exposure time on image was 1 hour. Didac Mesa Romeu/Seichi Yoshida.

Comet C/2023 H2 (Lemmon) was discovered on 28 April 2023 by the University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount Lemmon in the Catalina Mountains north of Tucson. The designation C/2019 U6 (Lemmon) implies that it is a comet (C/), that it was the second comet-like body (2) discovered in the second half of April 2023 (period 2023 H - the year being split into 24 half-months represented by the letters A-Y, with I being excluded), and that it was discovered by the Mount Lemmon Survey (Lemmon).

The orbit and position of Comet C/2023 H2 (Lemmon) on 29 October 2023.  JPL Small Body Database.

Comet C/2023 H2 (Lemmon) has an orbital period of 3876 years and a highly eccentric orbit tilted at an angle of 114° to the plain of the Solar System, that brings it from 0.89 AU from the Sun at closest perihelion (89% of the distance between the Earth and the Sun to 493 AU from the Sun at aphelion (493 times as far from the Sun as the Earth or about 16.4 times as far from the Sun as the planet Neptune, and considerably outside the Kuiper Belt). As a comet with a period of more than 200 years, C/2023 H2 (Lemmon) is considered to be a non-Periodic Comet, since it is unlikely that it would be identified as the same body on another visit to the Inner Solar System.

Comet C/2023 H2 (Lemmon) is expected to pass by ot Earth on 10 November 2023, when the comet will reach 0.19 AU (28 424 000 km) from the planet at about 11.45 pm GMT. This is close for a cometary fly by of the Earth, although it will probably still not be naked eye visible.

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Outbreak of Diptheria in Guinea.

On 5 September 2023, the Ministry of Health of Guinea notified the World Health Organization of a Diphtheria outbreak in the country. From 4 July to 13 October 2023, a total of 538 cases of Diphtheria, were reported in the Kankan Region, in the east-central part of Guinea, according to a press release issued by the World Health Organization on 18 October 2023. Of the total cases reported, 520 are suspected and 18 confirmed with 58 deaths including 13 among confirmed cases (a case fatality rate among all cases of 11%). The 1-4 years age group accounted for the largest proportion of reported cases. Diphtheria is a highly contagious vaccine-preventable disease caused mainly by the Bacterium Corynebacterium diphtheriae which can be fatal in 5-10% of cases, with a higher mortality rate in young children. However, in settings with poor access to Diphtheria antitoxin, the case fatality rate can be as high as 40%. Diphtheria remains a significant health problem in countries with poor routine vaccination coverage. According to World Health Organization/UNICEF estimates of national immunization coverage, the immunization coverage with the Diphtheria Tetanus toxoid and pertussis containing vaccine was reported to be 47% for 2022 in Guinea and has remained below 50% since 2014. This is insufficient for achieving the coverage of 80–85% required to maintain community protection. The World Health Organization assesses the risk of Diphtheria to be high in Guinea, considering the chronically low vaccination coverage.

On 4 July 2023, two children aged 2 and 4 years, attended the otolaryngology department of the Siguiri Prefectural Hospital in the Kankan Region of Guinea, for similar symptoms (dyspnea, dysphasia, fever, cough). They were hospitalized for tonsillitis and respiratory infection and received antibiotic treatment before being referred to the Kankan Regional Hospital for additional care.

Since 4 July and as of 13 October 2023, 538 cases have been reported, including 18 confirmed cases. In total, 58 deaths including 13 among confirmed cases were registered, and 461 contacts are being followed up. Of the cases reported, 62% are female. The 1-4 years age group, with 445 cases, accounted for the largest proportion of reported cases, 82%, followed by the 5-9 years age group, with 5% and 5% for the 10 years and above age group. Children under the age of 12 months make up 7% of reported cases. None of the 538 cases were vaccinated.

Kankan Region is divided into five prefectures and only the Kérouané Prefecture has not reported any cases to date. The prefecture of Siguiri is the most affected, with 510 cases (95%). Of the 363 patients admitted to the treatment centres in Siguiri, 37 (10%) have died. Other prefectures reporting cases are Mandiana (13 cases), Kankan (13 cases) and Kouroussa (two cases).  Of the 15 patients admitted in the treatment centre in Kankan, 12 (80%) have died.

The treatment centres in the country do not have the capacity in terms of Human resources and material for adequate case management. Suspected and confirmed cases were treated with Amoxicillin and Azithromycin as first line therapy. Antibiotic prophylaxis (Amoxicillin, Azithromycin) was administered to the direct contacts.

Distribution of Diphtheria cases in Kankan region, Guinea, as of 13 October 2023. World Health Organization.

Diphtheria is a highly contagious vaccine-preventable disease caused mainly by Corynebacterium diphtheria but also by Corynebacterium ulcerans. It spreads between people mainly by direct contact or through the air via respiratory droplets. The disease can affect all age groups; however, unimmunized children are most at risk.

Symptoms often come on gradually, beginning with a sore throat and fever. In severe cases, the Bacteria produce a poison (toxin) that causes a thick grey or white patch at the back of throat. This can block the airways, making it hard to breathe or swallow, and also creates a barking cough. The neck may swell in part due to enlarged lymph nodes.

Treatment involves administering Diphtheria antitoxin as well as antibiotics. Vaccination against Diphtheria has been effective in reducing the mortality and morbidity from Diphtheria dramatically. Diphtheria is fatal in 5-10% of cases, with a higher mortality rate in young children. However, in settings with poor access to Diphtheria antitoxin, the case fatality rate can be as high as 40%.

Guinea has strengthened epidemiological surveillance for early detection and case management. Daily coordination and monitoring meetings on the response activities are underway at the Regional level, led by the regional health inspector and with the support of the World Health Organization, Médecins Sans Frontières-Belgium and other partners in the region. Notification of all suspected cases of Diphtheria, investigation initiation, and monitoring of contacts as soon as possible has been enhanced. Contact tracing, identification of an isolation zone at the Balato Health Post in the prefecture of Kouroussa and briefing of the healthcare workers on the case definition and prevention measures are ongoing. Case management activities such as antibiotic therapy (Amoxicillin, Azithromycin), treatment of suspected cases, antibiotic prophylaxis (Amoxicillin, Azithromycin) for the direct contacts and free case management at treatment centres with support from Médecins Sans Frontières are being provided. Risk communication and community engagement efforts, such as raising awareness of cases in the community and identifying and briefing a communicator to raise awareness among parents of patients is ongoing.

Suspected Diphtheria cases by epidemiological week in Guinea, as of 13 October 2023. World Health Organization.

The Diphtheria antitoxin supply is currently very constrained and insufficient to respond to current demands, as there is only a limited number of manufacturers and large outbreaks are being reported in different regions of the world.

The risk of Diphtheria in Guinea is considered high due to the low vaccination coverage in the affected region (36% according to the survey coverage in households, 2023) and 47% national vaccination coverage between 2014-2022 (per World Health Organization/UNICEF estimates), and the risk at the regional level is moderate and low at the global level. The outbreak is also characterized by high case fatality among confirmed cases. Other factors include: the over population of the Siguiri Health District, which is the epicentre of this outbreak, the weakened healthcare system and several concurrent epidemics in the area.

Overpopulation of the Siguiri Health Prefecture, the epicenter of this epidemic, as well as the insufficient and poorly qualified health personnel, and the limited material resources of the health system weakens the response to this outbreak. In addition, the country is facing several concurrent epidemics in the area, such as Pertussis, Poliomyelitis, and Rabies. Adding this to a context of extreme vulnerability due to mining activities, which induce significant population movement, reduce air quality, and increase the risk of natural disasters such as floods and landslides, impacting people’s health.

This emphasizes the urgent need to strengthen Diphtheria vaccination coverage nationwide, especially in the epicentre and strengthen case management at hospital facilities dealing with Diphtheria cases.

The control of Diphtheria is based on primary disease prevention by ensuring high population immunity through vaccination and secondary prevention of spread by the rapid investigation of close contacts to ensure prompt treatment of those infected.

The World Health Organization advises that epidemiological surveillance ensuring early detection of Diphtheria outbreaks should be in place in all countries, and all countries should have access to laboratory facilities for reliable identification of toxigenic Corynebacterium diphtheriae. Adequate quantities of Diphtheria antitoxin should be available nationally or regionally for the medical management of cases.

Vaccination is vital to preventing cases and outbreaks, and adequate clinical management involves administering Diphtheria anti-toxin to neutralize the toxin and antibiotics reducing complications and mortality.

The World Health Organization recommends early reporting and case management of suspected Diphtheria cases to initiate the timely treatment of cases and follow-up of contacts and ensure the supply of Diphtheria antitoxin.

Although travellers do not have a particular risk of Diphtheria infection, it is recommended that national authorities remind travellers going to areas with Diphtheria outbreaks to be appropriately vaccinated in accordance with the national vaccination scheme established in each country before travel. A booster dose is recommended if more than five years have passed since their last dose.

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Lithocarpus tapanuliensis: A new species of Stone Oak from northern Sumatra, utilised as a food source by Orangutans.

The tropical rainforests of Sundaland (Bali, Borneo, Java, Sumatra, the Malay Peninsula, and the surrounding small islands) form one of the most biologically megadiverse regions on Earth, with each landmass containing fragments of a larger forest which once covered the now largely submerged Sundaland landmass. The island of Sumatra, once considered to be too similar to Peninsula Malaysia to merit much study, is now recognised as one of the most diverse regions within Sundaland, possibly containing as many Plant species as the much larger island of Borneo; significantly more than the islands of Java or Sulawesi. The island is also home to a variety of Critically Endangered megafauna, including Sumatran Elephants, Elephas maximus sumatranus, Sumatran Rhinoceros, Dicerorhinus sumatrensis, Sunda Tiger, Panthera tigris sondaica, and Sumatran and Tapanuli Orangutans, Pongo abelii and Pongo tapanuliensis.

Stone Oaks, Lithocarpus spp., are currently considered to be the second largest genus within the Family Fagaceae, with about 347 named species (only the True Oaks, Quercus spp., have more, with around 600), including 32 species found on Sumatra, five of which are entirely endemic to the island. Stone Oaks are found across the island of Sumatra, found in all forest environments, although individual species tend to have limited elevation ranges, and the group is at its most diverse between 400 m and 700 m above sealevel. Fagacean trees, along with Laurels, Lauraceae, and Myrtles, Myrtaceae, form major components of the lower montane forests of Sumatra, between 900 m and 1500 m above sealevel, and eight species are known from the Sumatran upper montain forest, 1400-2500 m above sealevel.

The Batang Toru Ecosystem consists of a mosaic of mixed plantations and primary and secondary forests, with three remaining large forest blocks, the largest of which is the South Tapanuli Block, which forms the last refuge of the Critically Endangered Tapanuli Orangutan. 

In a paper published in the journal PhytoKeys on 20 October 2023, Try Surya Harapan of the Southeast Asia Biodiversity Research Institute and  Center for Integrative Conservation at the Xishuangbanna Tropical Botanical Garden, the Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation and Yunnan Key Laboratory for Conservation of Tropical Rainforests and Asian Elephants, and the Herbarium at Universitas Andalas, Wei Harn Tan of the Faculty of Science at Universiti Brunei Darussalam, Thoriq Alfath Febriamansyah, Nurainas, and Syamsuardi, also of the Herbarium at Universitas Andalas, and Joeri Sergej Strijk of the Alliance for Conservation Tree Genomics at the Pha Tad Ke Botanical Garden, describe a new species of Stone Oak from the South Tapanuli Block, observed to be a food source utilised by Tapanuli Orangutans. 

The new species is named Lithocarpus tapanuliensis, where 'tapanuliensis' means 'from Tapanuli'. It is a large forest tree, reaching 35 m without any buttresses. It's bark is greyish-green with whitish lenticels, fissured in place to form longitudinal slits exposing a dark red inner bark. Leaves are elliptic to oblong in shape, reaching 20 cm in length and 8.5 cm in width, dark green above, and fawnish green on the underside, which is covered with woolly hair. Flowering of the tree has not been observed, but acorns 1.9–2.3 cm in length are born in cups 2.8–3.4 cm in diameter.

Lithocarpus tapanuliensis. (A) Fresh fruits from field collection, (B) fresh fruits in the canopy, (C) bark and sapwood, (D) fresh leaves, (E) dried mature and immature infructescence, (F) base of tree next to an Animal wallow, (G) cupule- bottom view, top view and nut bottom view and cross-section. Harapan et al. (2023).

The species was discovered during a field survey carried out in February 2023; only two trees were observed, growing at an altitude of 894 m within Pilar Forest of the South Tapanuli Block. A number of collected acorn remnants showed signs of having been fed upon by Orangutans, and an Orangutan was observed nesting in a neighbouring tree (Orangutans tend to nest near to, but not in, food trees, to avoid being disturbed by other Animals when they sleep). The consumption of the acorns, leaves and bark of Fagaceaen trees by Orangutans has previously been recorded, although these is generally overlooked as a food source in studies of the Apes. It is likely that acorns serve as a reliable source of food during periods of fruit-scarcity, caused by the multi-annual fruiting cycles of many rainforest trees. Asian Black Bears, Ursus thibetanus, and Malayan Sun Bears, Helarctos malayanus, have also been observed consuming acorns during periods of low fruit abundance.

(A) Acorns consumed by Orangutan. (B) Orangutan nest in a neighbouring tree. Harapan et al. (2023).

Only two specimens of Lithocarpus tapanuliensis has been observed, both within Pilar Forest. This forest is small, lacks any legal protection, and extensive habitat alteration and forest clearance are occurring within the immediate area to where the trees were found. For this reason Harapan et al. recommend that Lithocarpus tapanuliensis be classified as Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species.

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Rail lines in Westchester County, New York, blocked by landslide.

Rail services on the Hudson Line between Tarrytown and Croton-Harmon in Westchester County, New York, were disrupted for more than a day following a landslide which covered the tracks on Saturday 21 October 2023. The landslide occurred after a period of heavy rainfall in the area. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

A landslide at Scarborough in Westchester County, New York covering part of the Hudson Line between Tarrytown and Croton-Harmon on Saturday 21 October 2023. Westchester County Police Department.

Landslide expert Dave Petley of the University of Hull has examined images of the landslide, and in his Landslide Blog written that the landslide appears to have been caused by the failure of a retaining wall above the track, parts of which can be seen lying on the track following the landslide. This wall appears to have been used to create a flat garden area upon the hill above the track, with a filling behind is made up of soil and debris from the levelling of the ground behind, and appears to have failed when this soil became waterlogged, either due to poor planning or poor maintenance.

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Partial Lunar Eclipse.

A partial Lunar Eclipse will occur on Saturday 28 October 2023, starting slightly after 6.00 pm GMT. The whole eclipse will be visible across all of Europe, most of Africa and Asia, and the entire Indian Ocean, while part of the eclipse will be visible from the remaining areas of Africa, Asia and Australia, as well as parts of the Americas, although in these areas the Moon will either rise part way through the eclipse, or set before it is complete.

Areas from which the 28 October 2023 Lunar Eclipse will be visible. In the white area the full extent of the eclipse will be visible, in the shaded areas it will either begin before the Moon rises or end after the Moon has set, while in the darkest area it will not be visible at all. US Naval Observatory/HM Nautical Almanac Office.

The Moon produces no light of its own, but 'shines' with reflected light from the Sun. Thus, at Full Moon the Moon is on the opposite side of the Earth to the Sun, and its illuminated side is turned towards us, but at New Moon the Moon is between the Earth and the Sun, so that its illuminated side is turned away from us.

Lunar eclipses occur when the Moon passes through the Earth's shadow. This can only happen at Full Moon (unlike Solar Eclipses, which happen only when the Moon passes between the Earth and the Sum, and therefore only occur at New Moon), but does not happen every Lunar Month as the Sun, Moon and Earth are not in a perfect, unwavering line, but rather both the Earth and the Moon wobble slightly as they orbit their parent bodies, rising above and sinking bellow the plane of the ecliptic (the plane upon which they would all be in line every month).

Because the Moon is passing through a shadow, rather than being blocked from our view, it does not completely disappear during an eclipse like the Sun, but in a total Lunar Eclipse goes through two distinct phases of dimming, the Penumbra, when it is still partially illuminated by the Sun, and the Umbra, when the Earth completely blocks direct sunlight from the Moon. This does not result in complete darkness, as the Moon is still partially lit by reflected Earthlight, but it does turn a deep, dark red colour.  In a partial eclipse the Earth passes completely through the Moon's penumbra, but only partly through its umbra.  

Phases of the Lunar Eclipse that will be seen on 18 October 2023. The times are given in GMT, to the nearest 10th of a minute, thus 22.28.3 represents 18 seconds after 10.28 pm GMT. US Naval Observatory/HM Nautical Almanac Office.

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