Archive for May, 2010

Sunday Article: Vanishing Species – Forest Owlet

Sunday Article by Mohan Pai
 
 
Forest Owlet
Athene blewitti
 
 

Sighted in the wild for the last time in 1884, it was rediscovered after 113 years in1997.Only 100 breeding pairs survive in the wild.

The Forest Owlet, Athene blewitti, had not been seen in India last in1884. The last confirmed record- a specimen in Britain’s Natural History Museum – was collected in 1884. Believed to have been extinct for over a century, 113 years to be precise, it was rediscovered by Pamela C. Rasmussen, Ben King and David Abbott at Shahada near Taloda in the Nandurbar district of Maharashtra (Toranmal Reserve Forest) in India in November 1997.

How this rediscovery came about is a fascinating story, involving theft, fraud, and international espionage. In the course of working on a field guide to the birds of the Indian subcontinent, ornithologist Rasmussen became aware of irregularities in the records of Colonel Richard Meinertzhagen, a World War I British spy and colorful character who early in this century owned what was generally considered to be the finest private collection of Old World birds in existence. Through painstaking research, she and her colleague, Nigel J. Collar of Birdlife International, were able to show that Meinertzhagen’s specimen of a Forest Owlet–which he had supposedly collected in 1914, was a fraud and had been taken from an existing 19th-century collection.

The species epithet commemorates F. R. Blewitt, the collector of the first specimen that was obtained in December 1872 from Busnah-Phooljan near Basna on the Phuljar highway in eastern Madhya Pradesh. The specimen was sent to Allan Octavian Hume who described it in 1873.

The Forest Owlet is small (23 cm) and stocky. It is a typical owlet with a rather unspotted crown and heavily banded wings and tail. They have a relatively large skull and beak. Unlike the Spotted Owlet, the Forest Owlet has the fewer and fainter spots on the crown and back. The upperparts are dark grey-brown. The upper breast is almost solid brown and the sides are barred with a white central wedge in the lower breast that is sometimes unmarked, especially in males. The primaries are darker and distinct. The wings and tail are banded with white trailing edges. A dark carpal patch on the underwing visible in flight. The facial disc is pale and the eyes are yellow.

Distribution and habitat

Until its rediscovery in 1997, this owl was known from only seven specimens collected in the nineteenth century, in northern Maharashtra, and south-east Madhya Pradesh/western Orissa. In November 1997 a group of American ornithologists, including Pamela C. Rasmussen, rediscovered the species in foothills of the Satpura Range, north-east of Bombay. In 2000 a survey of 14 forest areas across its former range located 25 birds (using call playback) at four sites in northern Maharashtra and south-western Madhya Pradesh, including three pairs at Taloda Forest Range and seven pairs at Toranmal Forest Range. No birds were found in a brief survey of its former eastern range in Orissa. More recently survey efforts in the Satpura Range added another five sites. The species was also reported from the Chatwa and Padwa forests near Andhra Pradesh by K. S. R. Krishna Raju

The Forest Owlet has sightings from the Talda Forest Range, the Toranmal Forest Range, the Melghat Tiger Reserve, and the Khaknaar Forest Range, all in central India had dense to open deciduous forest.

Behaviour

These owls typically hunt from perches where they sit still and wait for prey. When perched they flick their tails from side to side rapidly and more excitedly when prey is being chased.. When nesting the male hunted and fed the female at nest and the young were fed by the female. The young fledge after 30–32 days

The peak courtship season is in January to February during which time they are very responsive to call playback with a mixture of song and territorial calls.

They appear to be strongly diurnal although not very active after 10 AM, often hunting during daytime. On cold winter mornings they bask on the tops of tall trees. Filial cannibalism by males has been observed.

They make several different calls. These include a hissing call of short duration. The song calls are short and mellow unlike those of most owls.

Status

The Forest Owlet remains critically endangered, and the current population has been estimated at about 100 breeding pairs. It is thought that this owl has always been rare. The original specimens were collected in dense jungle, and the recent sightings in more open forest may also represent a habitat. The forest in the plains in its range has been totally cleared, and there is pressure on the remaining forest resources.

 

Until recently, the best illustration of the Forest Owlet was the one above, which appeared in The Scientific Results of the Second Yarkard Mission, published in 1891. the illustration has several inaccuracies: the cheek patches are too dark and the breast is too barred; the belly, lower flanks, and undertail coverts should be completely white, not marked; the bands in the wing should be whiter; and the bill should be larger.
 
 
References: Wikipedia, Copperwiki, “Lost & Found” by Tim Gallagher.
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Sunday Article: Vanishing species – the Purple Frog

Sunday Article by Mohan Pai

 
 The Purple Frog
Nasikabatrachus sahyadrensis
 
                                                                                          Pic courtesy: Sathyabhama Das Biju
 
100 million-year old species discovered in Idukki district of Kerala in 2003
 
The purple frog is a living fossil and was initially assigned to a new family of its own, Nasikabatrachidae, buthas been more recently assigned to the family Sooglossidae which is found on the Seychelles islands.

Being a member of the family Sooglossidae, the species’ origins lie in close consort with the Seychelles islands where the family was previously solely known from. The origin of the disjunct distribution goes back to about 100 million years ago, during which time India, the Seychelles and Madagascar formed a single landmass which split due to continental drift.
 
The body of the Purple Frog is shaped similarly to that of most frogs, but is somewhat rounded compared to other frogs. Its arms and legs splay out in the standard anuran body form. Compared to other frogs, it has a small head and an unusual pointed snout. Adults are typically dark purple in color. The specimen with which the species was originally described was seven centimeters long from the tip of the snout to the tip of the urostyle. Also, its cry sounds more like one from a chicken.

The species was discovered in the Idukki district of Kerala by S.D. Biju from the Tropical Botanic Garden and Research Institute in Palode, India and Franky Bossuyt from the Vrije Universiteit Brussel (Free University of Brussels). However it was well known to the local people before and several earlier specimens had been ignored.
 
Earlier thought to be restricted to the Western Ghats south of the Palghat gap, new records have extended its known range further north of the gap.

The frog spends most of the year underground, surfacing only for about two weeks, during the monsoon, for purposes of mating. The frog’s reclusive lifestyle is what caused the species to escape earlier notice by biologists.

Unlike many other burrowing species of frogs that emerge and feed above the ground, this species has been found to forage underground feeding mainly on termites using their tongue and a special buccal groove. They show inguinal amplexus (male clasping the female from behind) when mating afloat in temporary rainwater pools.

The scientific name derives from the Sanskrit word nasika (nose) referring to the pointed snout, batrachus Greek for frog, and Sahyadri as the local name of the mountain range where it was found – the Western Ghats.
 
Distribution

This species is endemic to the Western Ghats in India, and is known from only two localities in the Idukki District in the Cardomom Hills, Kerala at an altitudinal range of 850 – 1,000m above sea level. These two areas are Kattapana and near Idukki town. It might occur more widely, but it seems that other reported localities probably refer to currently undescribed species.

The purple frog is thought to be a rare species, although it is very hard to find which makes any population estimate difficult to determine. Only 135 individuals have so far been observed, and of these only three have been females. The plantation workers within the range of this species have reported that this frog is uncommonly found when they are cutting trenches during the monsoon period (June to October).

Status

The purple frog is listed as Endangered in the IUCN Red List of Threatened Species because its extent of occurrence is less than 5,000 km sq., all individuals found are in fewer than five locations, and there is a continuing decline in the extent and quality of its habitat in the Cardmom Hills, Western Ghats.The main threat to the purple frog is believed to be ongoing forest loss for coffee, cardamom, ginger and other species for cultivation.
 
 

 
Possible Indian odysseys: three models of the position of Africa 65 million years ago. a, India separated by large expanse of water b, limited land bridge between Africa and India c, connections between Africa, India, Asia and Madagascar.

Image courtsey Nature.

References: Wikipedia, Genome News Network.

Sunday Article: Vanishing species- Pygmy Hog

Sunday Article by Mohan Pai
Hello friends,

Good morning. A number of my readers wrote asking why the Sunday Articles had stopped.

Unfortunately, I had to undergo an emergency cardiac surgery and hence this long intervening gap.

This Sunday, it’s about the Pygmy Hog, a highly endangered species. In fact it is more endangered than the tiger ! Only about 150 animals survive in the wild only in Assam (Manas National Park).

When it comes to conservation, the flagship species like the tiger, rhino, etc. hog the limelight. The plight of the lesser vulnerable, critically endangered animals gets hardly any attention.

Very best wishes,

Mohan Pai

Pygmy Hog
Sus salvanius

The smallest pig in the world is also more endangered than the tiger !
Only 150 animals survive in Assam.

The Pygmy Hog is critically endangered with less than hundred and fifty thought to be left in the wild. Once native to India, Bhutan and Nepal, these little guys were thought extinct from the 1950s-60s, until a small population was discovered. They can now be found only in the northwest Assam region in India. The pygmy hog is notable as it is the only surviving member of the genus Porcula.

The pygmy hog is a small wild pig weighing about 8.5 kg (10 lb). It lives in dense, tall grassland, where it feeds on roots, tubers and other vegetable matter, as well as insects and other invertebrates. Nests are built and used by both sexes at all times of the year. The pygmy hog is apparently non-territorial. It lives in small family groups of about 4 – 5 individuals, comprised of one or more adult females and accompanying juveniles, and occasionally an adult male.

The pygmy hog formerly occurred throughout the Terai region of India, Bhutan and Nepal. It is now found only in northwest Assam, India. By 1993 it was reduced to only two known, isolated populations in northwest Assam – the Manas Wildlife Sanctuary and the Barnadi Wildlife Sanctuary.

The continuing decline of the pygmy hog is due to the modification and elimination of its limited habitat by human settlement, agricultural encroachment, overgrazing by domestic livestock, commercial forestry, flood control projects, and civil unrest among Assamese ethnic groups.
Pygmy Hogs are about 55 to 71 cm long and stand at 20-30 cm with a tail of 2.5 cm. They weigh 6.6 to 11.8 kilograms. Their skin is dark brownish black and the fur is dark. Piglets are born grayish-pink becoming brown with yellow stripes along the body length. The head is sharply tapered and they have a slight crest of hair on the forehead and on the back of the neck. Adult males have the upper canines visible on the sides of the mouth. They live for about 8 years, becoming sexually mature at 1-2 years. They breed seasonally before the monsoons giving birth to a litter of 3-6 after a gestation of 100 days. In the wild they make small nests by digging a small trench and lining it with vegetation. During the heat of the day they stay within these nests. They feed on roots, tubers, insects, rodents, and small reptiles.

The species was first described as the only member of the genus Porcula (Hodgson, 1847), but was then regarded as the closest relative of the Eurasian pig Sus scrofa and named Sus salvanius The resurrection of the original genus status and the species name Porcula salvania has been adopted by GenBank. The species name salvania is after the Sal forests where it was found.

Status

The pygmy hog is the sole representative of Porcula, making the conservation of this critically endangered species even more important as its extinction would result in the loss of a unique evolutionary branch of pigs. They used to be widespread in the tall, wet grasslands in the southern Himalayan foothills from Uttar Pradesh to Assam, through Nepal and north Bengal. However, human encroachment has largely destroyed the natural habitat of the pygmy hog by development, agriculture, domestic grazing and deliberate fires. Only one viable population remains in the Manas Tiger Reserve, but even there threats due to livestock grazing, poaching and fire persist. The total wild population has been estimated as less than 150 animals and the species is listed as “critically endangered” Their rarity contrasts greatly with the massive population of wild boars (Sus scrofa) in India.

Conservation

Conservation of the species has been hampered due to the lack of public support, unlike that for charismatic South Asian mammals like the Bengal Tiger or Indian Rhino. Local political unrest in the area has also severely hampered effective conservation efforts, but these conflicts have now ceased.

References: Wikipedia, Animal Kingdom, Zooillogix.

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