Survey reveals 27% growth in Bhutan's Tiger population.

A survey carried out by the Forest and Park Services Department of the Royal Government of Bhutan in 2021-22 has found that the current population of adult Bengal Tigers, Panthera tigris tigris, in the country is 131, a 27% increase since the last such survey was carried out in 2015. The species appears to be breeding at different altitudes within the country, suggesting that the increase in population is related to a genuine ecological recovery.

A Tiger imaged by a camara trap in Bhutan during the 2021-22 survey. Forest and Park Services Department of the Royal Government of Bhutan.

Tigers are currently considered to be Endangered under the terms of terms of the International Union for the Conservation of Nature’s Red List of Threatened Species, with the global population estimated to have declined between 53% and 68% between 1996 and 2014, and a range contraction of more than 50% during the past three generations. Tigers are solitary Big Cats requiring large territories and a supply of suitable prey, ideally Deer or Wild Pigs, to survive. As such they are highly vulnerable to habitat loss, as well as conflict with Humans, as many farmed Animals fall within the prey-size range of Tigers.

The current and former range of the Tiger. IUCN Cat Specialist Group.

Tigers were once found in Afghanistan, Armenia, Azerbaijan, Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Iran, Kazakhstan, Korea, Kyrgyzstan, Laos, Malaysia, Myanmar, Nepal, Pakistan, Russia, Singapore, Tajikistan, Thailand, Turkey, Turkmenistan, Uzbekistan, and Vietnam, however, they are now extinct in Afghanistan, Armenia, Azerbaijan, Cambodia, Iran, Kazakhstan, Korea, Kyrgyzstan, Laos, Pakistan, Singapore, Tajikistan, Turkey, Turkmenistan, Uzbekistan, and Vietnam. Bangladesh, Bhutan, India, Indonesia, and Nepal have implemented rigorous monitoring and conservation plans for Tigers since the last ICUN assessment of the global population in 2015, with Bhutan, India, and Nepal all subsequently reporting rises in their Tiger populations.

A family of Tigers imaged by a camara trap in Bhutan during the 2021-22 survey. Forest and Park Services Department of the Royal Government of Bhutan.

The conservation of large predatory Animals such as Tigers is very much dependent on the co-operation of local populations. Tigers are known to take a large number of domestic Animals as prey in Bhutan, but the number of reprisal attacks is surprisingly low. Some of this can be attributed to a culture of respect for nature, however, a survey carried out by the World Wildlife Fund in Trongsa District, which lies entirely within the Jigme Singye Wangchuck National Park in the northeast of the country, found that people were concerned by the rise in the Tiger population, citing fears about livestock losses, and reporting that living close to the Big Cats is in itself stressful. The government of Bhutan has established Tiger Conservation Committees in several parts of the country, to encourage stewardship of the species, manage Human-Tiger conflicts, and provide livestock insurance, and the World Wildlife Fund is urging the government to set up more such committees, as well as planning to carry out similar surveys in other parts of the country.

A representative of the World Wildlife Fund interviewing a villager about attitudes to Tigers in Trogsa District, Nepal. Tashi Phuntsho/WWF-Bhutan.

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Stefania maccullochi: A new species of Carrying Frog from the Guiana Shield Highlands of northern South America.

The Guiana Shield is a range of ancient mountains covering much of French Guiana, Surinam, Guyana, and southern Venezuela. The area is one of the most biodiverse regions on Earth, particularly in the Highlands area, which comprises a series of flat-topped sandstone plateaus known as 'tepuis', which have been largely isolated from both one-another and the outside world for millions of years, giving rise to a huge number of endemic species (the area was the inspiration for Sir Arthur Conan Doyle's 'Lost World'). 

In a paper published in the journal Zoological Letters on 25 May 2023, Philippe Kok of the  Department of Ecology and Vertebrate Zoology at the University of Łódź and Department of Life Sciences at the Natural History Museum, describes a new species of Carrying Frog from Wei-Assipu-tepui, a 2260 m high flat-topped plateau on the border between Guyana and Brazil.

Carrying Frogs, Stefania spp., are a genus of Frogs restricted to the Guiana Shield, and for the most part to the tepuis of the Guiana Highlands. Most species are endemic to a single tepui, with most tepuis having 1-2 species, while the largest can have 5-6. A single species, Stefania evansi, is found in lowland environments. The group get their common name from their reproductive behaviour, with the females carrying their eggs on their backs until they hatch producing Froglets (there is no Tadpole stage), which are also carried until they are large enough to fend for themselves. The taxonomy of Carrying Frogs can be difficult, as all members of the group tend to be morphologically similar to one another and all species are quite variable in colouration. Furthermore, genetic analysis of Carrying Frogs has revealed that apparently similar populations are genetically distinct, while apparently morphologically distinct groups are in fact the same species.

Wei-Assipu-tepui has a surface area of a only 3 km³, and is entirely surrounded by high cliffs, so that it can only be reached by helicopter of ascending a vertical rock-face. The surface of the plateau is divided by a series of fractures, the deepest of which, Sima de los Guácharos, reaches more than 100 m beneath the plateau surface. The first recorded expedition to the plateau was in July 2000, when a joint expedition by the Sociedad Espeleológica Italiana and the Sociedad Venezolana de Espeleología visited the summit with the intention of exploring its cave systems. 

Summit of Wei-Assipu-tepui. (A) Aerial photograph taken facing southwest. (B) Aerial photograph taken facing northwest. Adrian Warren & Philippe Kok in Kok (2023).

The 2000 expedition to Wei-Assipu-tepui made a small collection of Amphibians was made, including a previously unknown species of Bush Toad, Oreophrynella sp., which was later described as Oreophrynella weiassipuensis, as well as a Carrying Frog, Stefania sp., which was never identified. The plateau was visited again in November 2009 by Philippe Kok, who spent two weeks there, collecting Amphibian and Reptile specimens. Kok collected nine species, including 23 specimens of a Carrying Frog morphologically identical to Stefania riveroi, a species known from Yuruani-tepui in Venezuela, about 20 km to the northwest of Wei-Assipu-tepui. However, a DNA analysis carried out several years later showed that these Frogs were not closely related to Stefania riveroi, instead forming a sister group to Stefania ayangannae, a morphologically distinct species found on Mount Wokomung, and Mount Ayanganna, two large tepuis in western Guyana, both more than 80 km to the east of Wei-Assipu-tepui. 

Based upon this, Kok describes the population from Wei-Assipu-tepui as a new species, which he names Stefania maccullochi, in honour of the Canadian herpetologist Ross Douglas MacCulloch, for his seminal contribution to the systematics and taxonomy of the genus Stefania in particular, and to the knowledge of the Amphibians and Reptiles of Guyana in general.

Main colour pattern variation in Stefania maccullochi. (A) IRSNB 15854, male. (B) NHMUK 2023.3188 (PK2098), female. (C) IRSNB 15855, female. (D) NHMUK 2023.3193 (PK2148), male. (E) NHMUK 2023.3192 (PK2137), male. (F) NHMUK 2023.3187 (PK2084), male. Kok (2023).

Stefania maccullochi is a large species of Carrying Frog, with the largest female found measuring 72.9 mm in length, while the largest male is 54.6 mm, with a head no longer than it is wide. Although this species appeared morphologically identical to Stefania riveroi on initial examination, a more thorough examination made after it was discovered the two populations were genetically distinct found that there were some subtle differences between the skeletons of the two species, most notably a deep indentation along the anteromedial base of the alary process of the premaxilla of Stefania maccullochi, which Stefania riveroi lacks, and the contact between the posterodorsal projection of the maxilla and the orbital/zygomatic ramus of the squamosal, which is fused in Stefania riveroi, while in Stefania maccullochi there is barely a contact.

Three-dimensional model of the cranium of the holotype of Stefania maccullochi. (NHMUK 2023.3184) based on computed tomography imagery. (A) Dorsal view. (B) Ventral view. (C) Frontal view. (D) Left lateral view. Abbreviations: ang, Angulosplenial; ang.cp, Coronoid process of the angulosplenial; col, Columella; c.p, Cultriform process; d, Dentary; exo, Exoccipital; fp, Frontoparietal; lam.p, Lamina perpendicularis; mmk, Mentomeckelian; mx, Maxilla; mx.pp, Posterodorsal projection of the maxilla; na, Nasal; na.mp, Maxillary process of the nasal; neo, Neopalatine; p.f, Pars facialis; pmx, Premaxilla; pmx. ap, Alary process of the premaxilla; pmx.lp, Lateral process of the premaxilla; pmx.pp, Palatine process of the premaxilla; pro, Prootic; psp, Parasphenoid; psp.ar, Alary process of the parasphenoid; psp.pp, Posteromedial process of the parasphenoid; pt, Pterygoid; pt.ar, Anterior ramus of the pterygoid; pt. mr, Medial ramus of the pterygoid; pt.pr, Posterior ramus of the pterygoid; qua, Quadratojugal; smx, Septomaxilla; sph, Sphenethmoid; squa, Squamosal; squa.or, Otic ramus of the squamosal; squa.vr, Ventral ramus of the squamosal; squa.zr, Zygomatic ramus of the squamosal; v, Vomer. Kok (2023).

Phylogenetically, Stefania riveroi has previously been seen as the sister species to the pairing of Stefania ayangannae and Stefania coxi, two species which are both found on the large tepuis Mount Wokomung and Mount Ayanganna, far to the east of Wei-Assipu-tepui. Both of these tepuis are noted for their high diversity of Stefania species, with six found on Mount Wokomung and five on Mount Ayanganna.

Distribution map of the Stefania riveroi clade as currently understood. Kok 2023.

Despite being morphologically very similar to Stefania riveroi, a species found on a neighbouring tepui, Stefania maccullochi was found to be the sister species to Stefania ayangannae. Kok suggests that this implies the species have a combination of retained ancestral traits and similar environmental pressures, both inhabiting small, high platues where they are the only species of Stefania found, while Stefania ayangannae and Stefania coxi inhabit larger, lower plateaus which they share with a range of other species. he furthermore designates the four species together as the 'Stefania riveroi clade' within the genus Stefania. Interestingly, molecular clock analyses suggests that the splits between these species are not recent, with no divisions between any species likely to be more recent than the Miocene.

Phylogenetic relationships of the Stefania riveroi clade, based on 2301 base pairs of nuclear and mitochondrial DNA (Bayesian statistical supports are provided at nodes), and comparison of crania in dorsal and lateral views. Circles and arrows highlight potential diagnostic characters: blue circles highlight absence/presence/location of a constriction in the frontoparietal bones; blue arrows highlight the condition of the frontoparietal crests; red arrows highlight the condition of (1) the contact between the posterodorsal projection of the maxilla and the orbital/zygomatic ramus of the squamosal, and (2) the contact between the maxillary process of the nasal and the maxilla. Kok (2023).

Wei-Assipu-tepui, the home to Stefania maccullochi, rises to 2260 m above sealevel and has a surface area of about 3 km³. Yuruani-tepui, the home to Stefania riveroi, reaches about 2400 m above sealevel, and has a surface area of 4.38 km³. The nearby tepuis of Roraima-tepui (2800 m), Kukenán-tepui (2600 m), Maringma-tepui (2100 m), and Maringma-tepui (about 2140 m) all appear to lack any species of Stefania.

The plateau of Wei-Assipu-tepui, is largely covered in vegetation, with  extensive areas of coarse herbs mixed with woody subshrubs on peat soils, as well as some quaking bogs and extensive patches of dwarf forests. These dwarf forests are dominated by Bonnetia roraimae, a flowering shrub found only on tepui tops. Other species common on the plateau are the Bromeliads Brocchinia tatei and Brocchinia reducta, the Rapateaceaen Stegolepis guianensis, the Yellow-eyed Grass Orectanthe sceptrum, and the Pitcher Plant Heliamphora nutans. The highest temperature recorded on the summit in the day was 29°C, and the lowest at night was 11°C. The relative humidity varied by between a minimum of 24% in the day and a maximum of 98% at night. All measurements were taken in November.

Main macrohabitats on the summit of Wei-Assipu-tepui. The clif visible in the background of (A) is the eastern fank of Roraima-tepui. Kok (2023).

Active Stefania maccullochi, including females with eggs, were observed at night, crawling on the ground and on low vegetation. Females with carried young were observed within Bromeliad tubes at night and by day, while another was found hiding under a rock by day. Other resting specimens were observed in the day on the ground, between rocks, and on trees as much as 2 m above the ground. On individual was observed sitting on a mossy rock at the bottom of a 30 m-deep crevice. No males were observed calling, but load single-note 'peeps' consistent with the a male Stefania.

Various females of Stefania maccullochi carrying eggs and juveniles. (A) & (B) Uncollected female carrying 9 juveniles. (C) NHMUK 2023.3190 (PK2122), carrying 10 eggs/metamorphs. (D) NHMUK 2023.3185 (PK2063), carrying 2 near-term juveniles. (E) & (F) IRSNB 15853, carrying 4 near-term juveniles. Kok (2023).

All known individuals of Stefania maccullochi have been observed within an area of less than 10 km², and that single location, the summit plateau of Wei-Assipu-tepui, is considered to be at threat from Human-set fires in the region, and the effects of climate change. It's isolation probably currently protects it from hazards such as Human-introduced pathogens such as Chytridiomycosis, although the species cannot be presumed to be completely safe, and strict hygiene protocols would need to be followed by documentary film-makers or others visiting the plateau. For these reasons, Kok considers that Stefania maccullochi should be considered to be Critically Endangered under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species. 

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Sphyrna mokarran: Critically Endangered Great Hammerhead Shark found dead in Alabama.

A female Great Hammerhead Shark, Sphyrna mokarran, has been found dead on a beach in Alabama. The Shark, which was found to be pregnant with 40 pups, was found floating in shallow water off Orange Beach, and pulled ashore by a group of members of the public on 20 April 2023. They informed Orange Beach Coastal Resources, who in turn contacted the Marine Fisheries Ecology Group at Mississippi State University. The Shark was taken to the university for a necropsy (the term 'autopsy' is reserved for Humans), although the cause of death could not immediately be determined. The Shark had not eaten for some time, but it is normal for female Hammerheads to fast while pregnant, so this is unlikely to have been the cause of death. Several of the Shark's organs have been sent for chemical testing. It is possible that the Shark could have been caught and then released by fishermen, only to die later of the shock, something which the species is known to be prone to.

A female Great Hammerhead Shark found dead of Orange Beach, Alabama, on 20 April 2023. Orange Beach Coastal Resources.

The Shark was 4.3 m in length and was carrying 40 unborn pups, each about 40 cm in length. Given the current conservation status of the species, this represents a significant loss (although it is highly unlikely that all 40 babies would have survived till adulthood under any circumstances). The University of Mississippi intends to preserve the baby sharks for used in educational outreach programs.

Unborn Shark pups recovered from the uterus of a dead Great Hammerhead Shark which washed up in Alabama. Mississippi State University Fisheries Ecology Group.

Great Hammerhead Sharks are found throughout tropical and warm temperate areas of the Atlantic, Indian, and Pacific Oceans, although genetic studies have suggested that this global population is in fact made up of two genetically distinct species, one found only in the Atlantic and the other in the Indo-Pacific. Population data is available from the Northwest Atlantic, Gulf of Mexico, and Indian Ocean, and in all places the species has shown a dramatic population loss over the past three generations, for which reason it is classified as Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. 

Distribution map for the Great Hammerhead Shark, Sphyrna mokarran. International Union for the Conservation of Nature.

The Northwest Atlantic population of Great Hammerhead Sharks is believed to have been overfished between 1983 and 1997, although there is uncertainty about how the population has fared since, with some studies suggesting that they have been spared overfishing since 2001, while others indicate that this has continued. Although the size of this population is uncertain, it is believed to have declined by at least 20% over the past three generations, a period estimated at 74.4 years for the Atlantic Ocean.

A Great Hammerhead Shark in life. Jeremy Stafford-Deitsch/International Union for the Conservation of Nature.

Another study, based upon data collected from long-line surveys off the coast of the US, has indicated that the population of Great Hammerhead Sharks has recovered somewhat in the Northwest Atlantic since 2005, and that this may even represent a slight increase in the population over a three generation time-span.

In the Indian Ocean, data collected by the Ocean Natal Shark’s Board's bather protection program between 1978 and 2003 suggests that the Great Hammerhead Shark population fell by an average of 6.5% per year over that time, which would equate to a 99.3% reduction over three generations (calculated as 71.1 years in the Indian Ocean).

Data on the Great Hammerhead Shark population, data gathered by the International Union for the Conservation of Nature from 20 separate fishing fleets operating in the area between 1998 and 2008 found a 61.7% decrease in the population over the ten year period, although this data was not considered reliable enough to extrapolate a three-generation trend.

In the Mediterranean, data on the Great Hammerhead as a separate species is not available, but overall data on Hammerhead Sharks, Shpyrna spp., indicates that the group has suffered a 99.99% decline in population since the early nineteenth century, effectively disappearing from this area. 

In the North and West Central Pacific it was again impossible to extract information for Great Hammerheads as a species, but data collated by the International Union for the Conservation of Nature suggests that the species is caught infrequently in these regions, probably indicating that it is present at only very low levels. Data is also limited from the coast of West Africa and tropical Indian Ocean, but fishing activity here is known to have increased significantly in recent decades, presumably applyinf pressure upon the species.

Based upon the data from the Northwest Atlantic, Gulf of Mexico, and southern Indian Ocean, the Great Hammerhead Shark population has undergone significant declines in population since the mid-twentieth century, although with some signs of a limited recovery in areas where properly run management schemes have been implemented. The Atlantic Population is believed to have undergone a decline of more than 50% over three generations, with a possible recovery in the Northwest Atlantic in recent years. In the Indo-Pacific region the Great Hammerhead Shark population appears to have declined by more than 80% over the last three generations, with no sign of a recovery anywhere in this range. 

Based upon this data the International Union for the Conservation of Nature classifies the Great Hammerhead Shark as Critically Endangered.

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Platyceps josephi: A new species of Racer from Tamil Nadu.

The Banded Racer, Argyrogena fasciolata, is a species of Colubrid Snake found across much of South Asia, which was first described in 1796 by the Scottish surgeon and naturalist Patrick Russell. Although widespread, the Banded Racer has a non-contiguous distribution (i.e. it's distribution is divided into many small local populations which do not connect) and is highly morphologically variable, which has led to repeated speculation that the 'species' may in fact represent a cluster of closely related species. This has led to many different classifications being proposed, but none of these have gained widespread acceptance, as taxonomists have been unable to agree on the criteria for describing new species, leaving to the retention of a single species to describe all populations, even though it is generally accepted that this is incorrect.

In a paper published in the journal Vertebrate Zoology on 13 May 2021, Veerappan Deepak of the Senckenberg Museum of Zoology, the Department of Life Sciences at the Natural History Museum, and the Centre for Ecological Sciences at the Indian Institute of Science, Surya Narayanan of the Suri Sehgal Centre for Biodiversity and Conservation of the Ashoka Trust for Research in Ecology and the Environment, Pratyush Mohapatra of the Central Zone Regional Centre of the Zoological Survey of India, Sushil Dutta of the Department of Zoology at Assam Don Bosco University, Gnanaselvan Melvinselvan of Dindugal in Tamil Nadu, Ashaharraza Khan of the Indian Herpetological Society, and Kristin Mahlow and Frank Tillack of the Museum für Naturkunde Berlin, describe a second species of Racer Snake from Tamil Nadu State, India.

Samples of tissue were extracted from samples Colubrid Snakes from across India and Pakistan, and DNA extracted from these using Qiagen DNeasy blood and tissue kits. They amplified partial sequences of two nuclear and three mitochondrial genes. Cytochrome b and NADH dehydrogenase subunit 4, 16S rRNA and the nu markers are oocyte maturation factor and recombination activating gene 1. 

Phylogenetic analyses were carried out using the CIPRES Science Gateway portal v3.3. PartitionFinder v2 was used (default MrBayes settings) to find the best-fit partition scheme for the concatenated dataset and model of sequence evolution for each partition. The best-fit scheme comprised six partitions. Deepak et al. estimated phylogenetic relationships using maximum likelihood and Bayesian inference.

Both the maximum likelihood and Bayesian inference found that the genus Platyceps was monophyletic (i.e. contained all the decendents of a single common ancestor) as long as the genus Argyrogena was included within it. For this reason they abolish the genus name Argyrogena, changing the formal name for the Banded Racer from Argyrogena fasciolata to Platyceps fasciolata. However, Deepak et al. note that the original name for the species was Natrix plinii, and that the species name should therefore now be Platyceps plinii.

The specimens sampled were found to fall into two distinct lineages, with one population comprising specimens from across Pakistan, northern, and central India, and one comprising specimens from Tamil Nadu State, in southern India. This population is therefore described as a new species, named Platyceps josephi (Joseph's Racer), in honour of the late Naveen Joseph, for his research on Reptiles, particularly Snakes in the Tuticorin region.

 

Map showing geomorphological features in parts of the Indian subcontinent and current locality records for Platyceps spp. mentioned in Deepak et al.'s study. Green (triangle) denotes the type locality and green (diamonds) for records of Platyceps plinii. Yellow (star) denotes the type locality, and yellow (circles) for the records of Platyceps josephi. Historically relevant names and important physiographic features are labelled. Deepak et al. (2021).

Platyceps josephi is a medium-sized Snake, with a maximum total length of 951 mm. It has a countersunk lower jaw, a dark brown dorsal service with white speckles, and two 'Π'-shaped white markings with black edges, on either side of the back of the head, behind the parietals, and extending into the body, and 34–48 prominent white bands on the body in both juveniles and adults. The body of Platyceps josephi is subcylindrical, being somewhat dorsoventrally flattened. The head is ovate, and barely wider than the anterior end of body. 

 

Platyceps josephi in life from various parts of Tamil Nadu state, India: (A) Holotype NCBS-AU732 (female, snout-vent length: 757 mm) from Tuticorin, (B) Paratype NCBS-AU733 (female, snout-vent length: 608 mm) from Tuticorin, (C) Paratype BNHS 3516 (female, snout-vent length: 592 mm) from Tuticorin, (D) uncollected (juvenile) from Tuticorin, (E) Paratype ZSI-CZRC-6639 (male, snout-vent length: 574 mm) from Karur, (F) Uncollected (male) from Vathalagundu, (G) uncollected (juvenile) from Tuticorin and (H) uncollected (female, snout-vent length: 655 mm) from Pollachi. Deepak et al. (2021).

Platyceps josephi is so far only known from Tamil Nadu State, India. It is reported from the Anaimallai Hills and different localities within the districts of Coimbatore (Anaikatti, Coimbatore, Pollachi), Dindigul (Batlagundu), Kanyakumari (Maruthuvazhmalai), Karur (Karur), Madurai (Madurai, Vadipatti), Salem (Salem), Theni (Meghamalai Hills), Thoothukudi (Tuticorin), Tirunelveli (Coutrallam, Manimutharu, Tirunelveli) and Villupuram (Auroville). The new species mostly inhabits open habitats with sandy or rocky patches in grasslands and scrublands in both inland and coastal areas of Tamil Nadu from elevations between 10 and 580 m above sealevel. Most of the areas where the species occurs receive less than 500 mm annual rainfall except locations near the rain shadowed areas close to the Western Ghats receives higher rainfall. The species is generally observed under thorny bushes, rock boulders, paddy fields, heaps of dry Coconut fronds and seen crossing roads, although several specimens were collected from Human habitations.

 

Habitats of Platyceps josephi in Tamil Nadu state, India: (A) close to the coast at the type locality Tuticorin, and (B) inland habitat near Anaikatti, Coimbatore. Deepak et al. (2021).

Platyceps josephi is a diurnal Snake, terrestrial and swift in locomotion. There is a report of arboreal behaviour under artificial conditions, but this is not known in the wild. It is an aggressive Snake, flattening its head as a mock hood display mimicking a Cobra, when agitated and biting freely, but it becomes docile after a few days in captivity.

The diet of the Platyceps josephi chiefly consists of Geckos, Lizards and small Rodents. It has been observed to kill the prey by constricting and/or crushing the prey against ground or tree trunk. In all captive observations, it swallows the prey from the head first. It is an oviparous Snake with few records of clutch sizes, 7–12 eggs during the month of March and June and have been reported, with the eggs being 40 mm in length. Females are reported to lay their eggs in bunds (raised areas surrounding the paddy fields) of paddy fields. 

Platyceps josephi is reported only from one protected area (the Megamalai Wildlife Sanctuary) in its known range. The species faces a number of threats across its distributional range, including habitat destruction, because the grasslands in southern Tamil Nadu are being actively converted into plantations, farmlands and urbanisation. Although there are records from such converted plantations and Human settlements, the species’ ability to adapt and its reproductive success is not known. Rocky habitats in Madurai region are also highly affected by the mining activities and road traffic is another important threat to Platyceps josephi. Three out of the seven specimens collected by Deepak et al. were roadkill and six other uncollected roadkill specimens were observed from various parts of Tamil Nadu between 2017 and 2020. The Area Of Occupancy of Platyceps josephi is 72 000 km² and Extent Of Occupancy is 70 698 km². Even though this is a relatively large area of distribution for a species, Deepak et al.'s field surveys and records suggest that this species has patchy distribution within its range. Also, much of the habitat in these regions where Platyceps josephi is reported are under severe threats like conversion of grasslands to farmlands, widescale monoculture plantations (Eucalyptus sp.) and urbanization. Given this information, Deepak et al. suggest that Platyceps josephi should be considered to be Vulnerable under the terms of the International Union for the Conservation of Nature’s Red List of Threatened Species.

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Coendou vestitus: Assessing the conservation status of the Brown Hairy Dwarf Porcupine in Colombia.

The Brown Hairy Dwarf Porcupine, Coendou vestitus, is one of the rarest of the seven species of Porcupines (genus Coendou) that occur in Colombia. It is a small species (head–body length 330–370 mm), characterized by having three types of fur: long dorsal fur, bicolored defensive fur, and bristles. Since its description more than a century ago, it has been recorded from only six localities. This species is considered endemic to both sides of the Eastern Cordillera in the Colombian Andes, which is a complex ecosystem with topographical and biological diversity and high levels of endemism. Andean ecosystems are a global conservation priority as only 25% of their original extent remains.

Although Coendou vestitus is considered rare this condition has not been evaluated, and it has been suggested based only on the absence of data and the paucity of voucher specimens. Information on the ecology, genetics, natural history and conservation status of the species is also scarce, and in the case of the latter, contradictory. This Porcupine is categorized as Data Deficient on the International Union for the Conservation of Nature's Red List of Threatened Species, with the assessment considering the presence of the species from only two localities, although in the same assessment three localities were mentioned. Nationally, the species has been categorised as Vulnerable based on its reduced geographical range as a result of habitat loss and fragmentation. Currently, it is the only Porcupine species categorised as threatened in Colombia. 

In a paper published in the journal Orynx on 17 November 2020, María Torres-Martínez of the Programa de Pós-graduação em Ecologia e Conservação and Laboratório de Biodiversidade, Conservação e Ecologia de Animais Silvestres at the Universidade Federal do Paraná, Héctor Ramírez-Chaves of the Departamento de Ciencias Biológicas and Museo de Historia Natural at the Universidad de Caldas, Elkin Noguera-Urbano of the Instituto de Investigación de Recursos Biológicos, Alexander von Humboldt, and Fernando Passos, also of the  Programa de Pós-graduação em Ecologia e Conservação and Laboratório de Biodiversidade, Conservação e Ecologia de Animais Silvestres at the Universidade Federal do Paraná, evaluate the level of rarity of the Brown Hairy Dwarf Porcupine and reassess its conservation status, based on available literature, specimens in natural history museums and collections, and data from recent records.

To evaluate the rarity of the species Torres-Martínez et al. followed the criteria of Jinpeng Yu & Stephen Dobson, based on four characteristics: (1) local population density, (2) range, (3) the number of habitat types in which the species occurs and (4) body size. In addition, Torres-Martínez et al. suggest factors that may have determined the rarity category of this species. As the species population density has not been assessed, Torres-Martínez et al. documented the number of records per year since the species description. They consider the population density to be low if the number of records evaluated is less than one for each ten-year interval (there are about 10 000 records of Mammals in databases for  Cundinamarca, the department in which Coendou vestitus has been historically recorded). Torres-Martínez et al. also estimated the species range and related this to the rarity level using the extent of occurrence and area of occupancy. They calculated the extent of occurrence using the minimum convex polygon (linking the known points of occurrence for the species), and the area of occupancy by summing the area of grid squares in which the species is known (using grid squares of 2 km² as recommended by the International Union for the Conservation of Nature) in GeoCAT. For this Torres-Martínez et al. used data from six confirmed localities. Three of these are voucher specimens housed at Colombian collections and the other three are photographic records. The photographs showed characters used to differentiate Coendou vestitus from other species in this genus: dorsal pelage with long blackish fur that partially or completely conceals defensive quills, and bicoloured bristle-quills. Torres-Martínez et al. excluded one voucher specimen, ICN 3505, from their analyses because the specimen was transported from another locality in the western part of the Eastern Cordillera; the location on the label of the specimen is in a market area.

Torres-Martínez et al. also considered the number of habitats occupied by the species. For this, they overlaid the extent of occurrence on the ecoregions of Colombia, following the classification of terrestrial ecoregions. Torres-Martínez et al. evaluated body size based on information from the labels of the reviewed voucher specimens and from the literature, and compared this trait with other species of Coendou.

To reassess the species conservation status, Torres-Martínez et al. used information on the level of rarity, extent of occurrence and area of occupancy. They included the level of rarity and the ecoregions the species inhabits to infer the conservation status of the species because of the absence of information on other factors that can influence the area of occupancy, such as biotic interactions (predation, competition) and landscape (connectivity and shelter). Torres-Martínez et al. also examined whether the extent of occurrence or area of occupancy of Coendou vestitus overlaps with protected areas, by using the protected areas layer for Colombia, and evaluated the per cent of forest area that remained unchanged during 2016-2017 within the polygon of the species range. To evaluate overlap of the area of occupancy and extent of occurrence with protected areas, Torres-Martínez et al. estimated the extent (km²) of protected areas inside the extent of occurrence polygon using as a limit the elevational range of the species, and determined the number of confirmed localities inside protected areas.

Torres-Martínez et al.'s findings indicate that Coendou vestitus matches the criteria of an extremely rare species

From the description of Coendou vestitus to the present, Torres-Martínez et al. found only 12 voucher specimens and photographs of three living specimens. Three records had no precise locality information. The records date from the species description in 1889 to photographic records from Cundinamarca in 2018. The scarcity of records suggests a low population density, considering that several biological expeditions have visited the area in which the species occurs (Cundinamarca is the Department in which Bogotá, the capital of Colombia and home of the main Colombian academic institutions, is located).

 

Photographic record (June 2018) of Coendou vestitus from Pedro Palo, Tena, Colombia. Sergio Chaparro in Torres-Martínez et al. (2020).

It has been suggested that the elevational range of Coendou vestitus is 1300–2600 m, 250-2000 m, and 600-1440 m. However, based on the information from confirmed localities, and discarding a dubious record from Villavicencio, the elevational range appears to be from 1250 m (Cundinamarca, Quipile) to 2600 m (Cundinamarca, Chicaque). The estimated area of the species range is based on only six confirmed localities, with an estimated extent of occurrence of 3320 km² and an area of occupancy of 24 km².

 

Extent of occurrence of Coendou vestitus, with (a) protected areas within the extent of occurrence, indicating the two records in protected areas, and (b) forest coverage in 2016-2017. Torres-Martínez et al. (2020).

Overlaying the extent of occurrence on the terrestrial ecoregions map indicated that the species only occurs in tropical moist broadleaf forest. This ecoregion corresponds to the highly threatened sub-Andean and Andean forests.

The adult body size of Coendou vestitus (total length of head and body 330-370 mm) is within the range observed for small Coendou species (Coendou insidiosus 310-350 mm; Coendou nycthemera 290-380 mm; Coendou pruinosus 320-380 mm; Coendou rufescens 340-410 mm; Coendou melanurus 330-435 mm; Coendou quichua 330-440 mm; Coendou speratus 330-440 mm; Coendou spinosus 285-470 mm; Coendou bicolor 450-500 mm; Coendou prehensilis 430-500 mm), being the third smallest species of the genus after Coendou ichillus (260-290 mm) and Coendou roosmalenorum (290 mm). Coendou vestitus has, however, a considerably shorter tail than the latter species.

Torres-Martínez et al. found only two localities (of the six confirmed) within conservation areas (33.3% of the occurrences), although the extent of occurrence polygon intersected with 35 protected areas, managed by two institutions (Corporación Autónoma Regional and Parques Naturales Nacionales de Colombia). Specifically, these 35 areas include one Soil Conservation District, five Regional Protected Forest Reserves, eight Regional Integrated Management Districts, and 21 Natural Civil Society Reserves. The portions of the protected areas within the extent of occurrence polygon have a total area of 1025 km², with 1298 km² of the extent of occurrence not lying within protected areas. When overlapping the forest coverage with the extent of occurrence polygon, the forest coverage during 2016-2017 was 219 km² (6.6%). Considering the species’ range and its rarity, Torres-Martínez .et al recommend that Coendou vestitus is recategorized from Data Deficient to Endangered based on the following criteria: an of less than 5000 km², and continuing decline inferred in extent and/or quality of habitat, number of locations or subpopulations, and the number of mature individuals, and similarly with an area of occupancy of under 500 km²; the population size is estimated to number less than 2500 mature individuals with a continuing decline, observed, projected, or inferred, and, continuing decline, observed, projected or inferred, in numbers of mature individuals, and extreme fluctuations in number of mature individuals.

Torres-Martínez et al.'s recommendation to categorise Coendou vestitus as Endangered follows International Union for the Conservation of Nature recommendations to assess poorly known taxa based on information on inferred habitat loss and restricted distribution, to avoid assigning a Data Deficient category. The current International Union for the Conservation of Nature information is incomplete (with area of occupancy and extent of occurrence unknown) because it includes data for only from two localities.  The periodic re-evaluation of a species’ Red List status is an important tool for the planning, monitoring and management of biodiversity conservation.

Besides being an endemic and rare species, Torres-Martínez et al.'s findings confirm that Coendou vestitus is restricted to an ecosystem in which habitat is being lost and there are continuing threats from anthropogenic transformation. The Eastern Cordillera comprises 40% of Andean ecosystems, but only 27% of its original vegetation cover remains. Although this region is characterised by high species richness and endemism it is one of the least known and least protected ecosystems. Habitat loss affects the persistence of small Mammals, which play important ecological roles, for example as seed dispersers of pioneer species, and in trophic and predator–prey relationships.

Although Coendou vestitus has previously been considered a rare species because of the scarcity of records, there are other reasons for it to be considered rare. Although other Porcupines in Colombia are known from fewer specimens (e.g. Coendou ichillus), they are not endemic to the country, having a wider distribution. Torres-Martínez et al.'s confirmation of rarity is based on a combination of apparent low local population density, a small range, occurrence in only one habitat type, and small body size.

In general, small-sized species of Coendou (e.g. Coendou. ichillus, Coendou roosmalenorum and Coendou vestitus) have more restricted distributions in the northern part of South America compared to the larger species that have only one type of quills in adulthood (e.g. Coendou prehensilis and Coendou bicolor). The rarity of Coendouvestitus is perhaps associated with homoplastic functional traits such as the presence of three types of hairs in adulthood (i.e. with less protection against predators than species with a body fully-covered by quills) and small body size. Several species of African small Mammals have been categorized as rare or Vulnerable because their size could influence predator–prey relationships. In this context, additional morphological characters may confer an adaptive advantage to large Coendou species: a body mostly covered by quills in adulthood provides a possible advantage against predators, the swollen nasofrontal sinuses protect the brain, and a larger tail facilitates arboreal locomotion, as observed in Coendoubicolor and Coendouprehensilis. The morphological and/or evolutionary reasons for the restricted range of small-sized Coendou are, however, as yet unclear, and require further research.

Although 106 genera, 333 species and 61 subspecies of Rodents are considered threatened and have high endemism, a relatively lower percentage of Rodents are categorised as threatened compared to other Mammalian groups. No Coendou species are as yet categorized as threatened, six are categorised as Data Deficient, including Coendou vestitus, and eight as Least Concern.

The only locations of Coendouvestitus within protected areas are in the 2.44 km² Nature Reserve Parque Natural Chicaque and the 0.45 km² Natural Civil Society Reserve Tenasuca de Pedro Palo, which together correspond to only 0.08% of the species’ range. In addition to the small extent of occurrence, the area of the 35 protected areas within the extent of occurrence is small (a mean of 29 km² per protected area). The area surrounding the extent of occurrence is severely affected by extensive commercial plantations and urban settlements, with only about 50% of the ecoregion unaffected. This limits connectivity, which is important for the persistence of a species. Maintenance, extension or connection of protected areas, connecting the relict habitats, could help to protect Coendou vestitus.

Conservation strategies and financial resources need  be established for threatened and endemic species and for species with restricted distributions. However, for Mammals most monitoring and conservation efforts are directed at large or charismatic species. Less attention has been directed at Rodents, even though the group has a high extinction rate. Prioritising the conservation of Coendou vestitus has the potential to contribute to the protection of the ecosystems in which it occurs and of co-occurring species. Torres-Martínez .et al recommend that national agencies prioritise this Porcupine species, together with other species in urgent need of monitoring.

Porcupines remain a poorly known group, both at national and Neotropical levels. Knowledge of the ecology of Coendou vestitus is mostly based on inference from other Porcupine species. Torres-Martínez et al.'s compilation of information on  Coendou vestitus highlights the need for further fieldwork and data collection. Nevertheless, threats to Porcupines are evident, in particular loss of habitat, illegal trade, road-kills, and hunting for consumption. In Colombia, illegal captivity has also been documented (on a voucher specimen label) as a threat to the species. Torres-Martínez et al.'s compilation of data and our findings form the basis for further research and for the establishment of conservation strategies and future evaluations of the distribution and conservation status of Coendou vestitus.

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