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INTRODUCTION CHAPTER 1

INTRODUCTION

1.1 A Introduction

On the occurrence of the Indian Eagle Bubo bengalensis it can be best said in the words of T. C. Jerdon (1862), 'There is not a rocky hill in the Camatic (present day

Kamataka state in south ), nor a ravine in the Deccan, where this owl may not be seen on the summit of a Indian, or a ledge, till long after sunrise, and looming large against the clear sky looking more like a quadruped than a .' The only change unfortunately is that the owl is by no means that common today (Plate 1).

Most are nocturnal while some are crepuscular in habit. Though they are not easily seen, they have made a tremendous impact on human thinking. The owls have forward facing almost human like eyes, they can turn the head in almost foil circle in various planes, they have a silent flight, they are cryptically coloured and are difficulty to observe for a greater period of time and many owls utter an eerie call at night, hence they arouse a feeling of fear, awe and mystery and not surprisingly the owls are deeply shrouded in the fog of superstitions. Owls are persecuted and killed out of fear wrong beliefs. Therefore, owls are also relatively less studied .

Rodents, shrews and other crop pests are recorded from the diet of owls and hence they are beneficial to the farmers. To throw hght on the life of one of the less studied owl species, I have undertaken the study of Indian Eagle Owl Bubo bengalensis.

1.1 B What is an owl?

Owls are arboreal, chiefly nocturnal birds of prey, characterized by large, round heads, short necks, round long wings and comparatively short . They have large round forward facing eyes, large ears with acute hearing ability, aided by the round facial disc that helps focusing of sound in the asymmetrically placed ears. The bill is

1 short, hooked and partially covered with feathers. The tarsus and toes are feathered, outer toe is reversible and claws are strongly hooked. The plumage is cryptic in colour, the broad, rounded wings are soft, velvety and have serrated margins that impart the ability of silent and buoyant flight that is not swift. The food is principally , they usually nest in hollows, the young are nidicolous and downy, and both parents attend the young (Ali and Ripley, 1969; Duncan, 2003). The word owl is derived from Middle English oule, from Old English ule, imitative in origin. So also in Sanskrit, the name Uluka for the owl is from its cry ululi. (Dave, 2007; Pande,

Suruchi 2009). Owls are grouped under Order Strigiformes in the Family Strigidae and Family Tytonidae. Generally speaking the owls are nocturnal predatory birds.

1.2 Owls in the world

The owls are found in almost all the from tropical regions to the Arctic polar region. The owls are distributed in various zoogeographic zones of the world such as the Neotropical, the Ethiopian, Oriental and Australian zones, and also in the

Palearctic and the Nearctic zones. In the analysis of 205 species of owls worldwide, there are 16 species of owls in the family Tytonidae and 189 species of owls in the family Strigidae; fiirther, the subfamily Striginae has 117 species and the tribe

Bubonini has 25 species (Duncan, 2003). Since new species of owls continue to be discovered, presently, about 217 species of owls are recorded from the world

(Rasmussen and Anderton, 2005).

1.3 Owls in the

About 38 species of owls (2 families and 12 genera) are recorded from the Indian

Subcontinent. Further, Family Tytonidae has 5 and family Strigidae has 31 species of owls; 2 additional species { seloputo from Nicobars and Strix hutleri from Mekran coast in ) are possibly recorded only once but there are no recent records. (Table 1) (Rasmussen and Anderton, 2005).

1.4 Bubo Dumeril, 1806

Kingdom: Animalia,

Phylum: Vertebrata,

Class: Aves

Order: Strigiformes,

A] Family: Tytonidae (Bam, Grass and Bay owls) and

B] Family: Strigidae (Owls, Owlets and allies), i) Subfamily: Striginae,

Tribe: Bubonini (Eagle-Owls and dM\QS-Bubo (Table 2), Ketupa, Nyctea and

Scotopelid). ii) Subfamily: Sumiinae,

Tribes : Sumiini, Aaegolini, Ninoxini. iii) Subfamily: Asioninae.

(The classification follows Ali and Ripley, 1969)

The recent classification as per Wikipedia is as follows:

Superregnum: Eukaryota

Supergroup: Unikonta

Cladus: Opisthokonta

Regnum: Animalia

Subregnum: Eumetazoa

Cladus: Bilateria

Cladus: Nephrozoa

Cladus: Deuterostomia Phylum: Chordata

Subphylum: Vertebrata

Infraphylum: Gnathostomata

Superclassis: Tetrapoda

Classis: Aves

Subclassis: Carinatae

Infraclassis: Neomithes

Parvclassis: Neognathae

Ordo: Strigiformes

Familia: Strigidae

Subfamilia: Striginae

Genus: Bubo

The Genus Bubo is quite well distributed in the world with 23 species but the members are not represented in Australia, New Zealand and further south (Table 2).

The genus has the most species diversity in Africa and . Almost a fourth of all the species in the genus Bubo are represented in India (Table 2 and 3). In all, 6 species of

Bubo owls are recorded from India, particularly Bubo bubo. Bubo bengalensis (Plate

1), Bubo nipalensis, Bubo coromandus, Bubo zeylonensis and Bubo flavipes. The comparative data about their distribution, status, , size, plumage, call, biometry, predominant pellet contents, nest sites and eggs of each species are summarized in

Table 3.

1.5 A. The Indian Eagle Owl Bubo bengalensis (Franklin, 1831) (Plate 1)

1.5 B. ETYMOLOGY Latin. Bubo, the eagle owl; Latin bengalensis, Related to

Bengal, formerly denoting North-East India (Pande 2009). 1.6 NAMES

1.6 A. COMMON NAMES Indian Eagle-Owl Bubo bengalensis syn. Bubo bubo bengalensis (Franklin), is also called Indian Great Homed Owl, Eagle Owl, The

Indian Homed Owl, Northem Eagle-Owl, Rock Eagle-Owl and Great Homed Owl.

(Jerdon, 1862; Baker, 1922-1928; Ali and Ripley, 1969).

1.6 B. LOCAL NAMES Ghugu (Hindi); Gug (Sind); Hutom pecha (Bengal); Ghubad

(Marathi); Ghuwad (Gujarati); Yerra gudla gubad (Telugu); Komban andai (Tamil);

Komban munga (Malayalam). (Jerdon, 1862; Ali and Ripley, 1969).

1.6 C. SANSKRIT NAMES Uluka, Pechaka, Vayasarati, Divandha, Kausika, Ghuka,

Divabhita, Nisatana Ghutkaraka, Hridilochana Naktachari, Kausi, Ghargaraka,

Bhiru, Kakasatru, Pingala, Dudula, Vrksarayi, Brhadravin, Pingalaksha, Bhyankara,

Tamasa, Kuvi, Ulukceti, Hikka, Kankasi, Kontha, Kakari, Harilocana, Nisadarsi,

Bahusvana, Mahapakshi, Krsna, Naktaka, and Krtamalaka. (Dave, 1985; Pande,

Sumchi, 2007).

1.7 A. ZOOLOGICAL NOMENCLATURE

Kingdom: Animalia,

Phylum: Vertebrata,

Class: Aves,

Order: Strigiformes,

Familiy : Strigidae (Owls, Owlets and allies).

Subfamily: Striginae,

Tribe : Strigini. (Eagle-Owls and dMiQS-Bubo, Ketupa, Nyctea and Scotopelid).

Genus: 5w6oDumeril, 1806, Zool. Ananlytique : 34. Type by tautonymy,

Strix bubo Linnaeus. Bubo bubo (Linnaeus) Cf. Vaurie, C, 1963, American Mus. Novitates, No. 2132:1-

10.

Bubo bubo bengalensis (Franklin) Otus bengalensis Franklin, 1831 (1830-31), Proc.

Zool. Soc. London:! 15. (The Ganges between Calcutta and Benares and in the

Vindhyan Hills between the latter place and Gurra Mundela) Baker FBI No. 1660,

Vol. 4:414 (Ali and Ripley, 1969).

1.7 B. CHRONOLOGICAL HISTORY OF NOMENCLATURE

Otus bengalensis Franklin, 1831 (1830-31) Proc, Zool. Soc. London: 115. Baker, FBI

No. 1660, Vol. 4-414. P.Z.S. 1831-Sydes, Cat. 18-Grould, Cent. Him. Birds, PI. 3-

Blyt, Cat. 143-Hors., Cat 88-Jerdon, Cat. 43-U. Cavearia, Hodgson. Urrua bengalensis, Franklin(Jerdon, 1862).

1.7 C. OR RACES

Four subspecies are described (Ali and Ripley, 1969) on the basis of colouration and wing lengh:

Bubo bubo bengalensis (Franklin) : darkest, richly coloured and wing 370-433 mm.

B.b. tibetanus Bianchi: dark and browner with wing 420-465 mm.

B.b. turcomanus (Eversmann): paler, grayer, feathered toes hide claws; wing 435-513 mm.

B.b. hemanchalana Hume : palest, sharp streaks on hind crown, wing 433-508 mm.

1.7 D. BUBO BENGALENSIS RECOGNIZED AS A SPECIES

The races Bubo bubo turcomanus (Turkestan Homed or Eagle-Owl), B.b. tibetanus

(Tibetan Homed or Eagle Owl) and B. b. hemachalana (Himalayan Homed or Eagle

Owl) (Plate 2) (vide AH and Ripley, 1969, Synopsis nos. 625-626a and Vaurie, 1965) are now grouped under a separate species Bubo bubo. The Eurasian Eagle-Owl and race Bubo bubo bengalensis is elevated to a species rank as Indian Eagle-Owl

{B.bengalensis) (Buceros, 1988 Vol. 3, August, No.2). So also, on the basis of DNA classification, Indian Eagle-Owl Bubo bengalensis and Eurasian Eagle-Owl Bubo bubo are designated as separate species (Wink and Heidrich, 1999).

1.8 STATUS AND KNOWN DISTRIBUTION

The Indian Eagle Owl Bubo bengalensis syn. Bubo bubo bengalensis, Franklin, is endemic resident of the Indian subcontinent and is found from coastal regions up to

1500 m altitude and rarely up to 2400 m altitude in Western . From

Kashmir, in India (with adjacent Punjab province and Kohat, Peshawar and

Rawalpindi districts in Pakistan), it extends eastwards up to West-Central . It is not reported from Sikkim, or North East Frontier Agency, but may be found there. It occurs from state in the west, across Gangetic Plain to the states of

Assam, Nagaland and Manipur, through and also . Southward it is found in Peninsular India up to Kanyakumari in suitable habitats. It is not recorded from and Andaman and Nicobar Islands (Jerdon, 1862; Baker, 1922-1928;

Ali and Ripley, 1969; Duncan, 2003).

1.9 FIELD IDENTIFICATION

1.9 A. Based on appearance: The large size with the overall height similar to the village hen, the 'horn-like' erect feather tufts on the crown, the 'cat-like' round face, the yellow iris, the vertical stance and the cryptic brown-buff plumage with streaks on the chest and belly are helpftil to identify this owl in the field. (Table 3) (Plates 1, 2)

(Ali and Ripley, 1969).

1.9 B. Based on call: The characteristic ghoo-ghoo call is a usefiil pointer for the identification of this owl in the field.

1.9 C. Based on habitat: This owl is encountered in the open semi-arid and dry grassland habitat with scrub vegetation, which is another usefiil pointer. It avoids . The perch sites are also usually prominent such as top of the rock, over the cliff face, atop a tree or on an electric pole.

1.10 BREEDING SEASON

Bubo bengalensis breeds during October / November to May, chiefly February to

April, but peak periods vary locally. (Ali and Ripley, 1969).

1.11 FLIGHT, FOOD AND FEEDING BEHAVIOUR

It is a nocturnal predator and issues forth at sundown heralded by a deep resounding double hoot. It flies with slow deliberate wing flaps interspersed with glides on outstretched wings and flies fairly close to the ground. (Plate 4). It is known to eat by active hunting (particularly rodents, but also birds, , , and ) (Ali & Ripley, 1969; Karim, 1994; Prashad, 1999; Duncan, 2003). It casts pellets that are freely littered below nests and daytime retreats. ftir, bones and skulls are almost invariably the components of such pellets. The predominant diet of field and mice suggest that it is of major significance to agricultural economy.

1.12 SOCIAL BEHAVIOUR

It keeps in pairs or may be seen singly. It spends daytime in the seclusion of dense foUage or in a fissure of rock, sheltered ledge in a ravine or among ruined and deserted buildings. When flushed it flies considerable distances in open sunshine with no obvious discomfort. The reftige is sought to escape the mobbing and chivvying from all diurnal birds as soon as it shows itself The species is known to keep to the home range throughout its life.

1.13 REVIEW OF LITERATURE

In the following two sections some of the major references pertaining to the study of owls in the global and Indian perspectives are discussed. 1.13 A. Global perspective

Owls are nocturnal and secretive in habits, and hence, are poorly studied in the world.

Most of the reports describe some aspect of behaviour, stray sighting, predator prey relationships, albinism, hybridization, mythology or socio-religion (Schodde, 1978;

Sage, 1983; Weinstein, 1989; Sterling, 1990). Miller (1935) discussed the vocal apparatus of the Elf Owl and the Spotted . Austing and Holt (1966), in a monograph on Great Homed Owl Bubo virginianus from the United States, discuss the various behavioral aspects of this owl in winter, spring, summer and fall. The basic anatomical and physiological aspects are broadly discussed. The feeding ecology, breeding biology, threats and conservation measures are also stated.

Comparative osteology of owls was studied by Ford (1967). Bunn (1982) and Hands

(1989) have worked on the Bam Owl. Mikkola (1983, 1994) has documented various species of the owls of Europe. Kemp and Calbum (1987) wrote a book on owls of

Southem Africa. Bull and Henjum (1990) and Bull and Duncan (1993) have studied the ecology of the Great Gray Owl Strix nebulosa. Haug (1993) published his work on the Burrowing Owl Speotyto cunucularia in North America. Cannings (1993) has worked on the Saw-whet Owl Aegolius acadicus of North America. Li (1993) has discussed owls as for Chinese medicine. Petty (1994) studied the molt pattem of Tawny Owl Strix aluco. Olsen and Trost, 1997; Plson and Taylor, 2001, Olson et al, 2002 a) studied some breeding aspects and vocalization of the Southem Boobook

Ninox novaeseelandiae in Australia. Duncan and Lane (1988) have studied breeding in Great Homed Owls in the US. Dimcan and Duncan (1998) have worked on the

Northern Hawk Owl Sumia ulula in North America. Molecular evolution and systematics of the owls was pubhshed by Wink and Heidrich (1999) in a landmark study. Another confribution to the scientific study of owls was the publication of the guidelines for nocturnal owl monitoring in North America (Takats et al, 2001).

Johnsgard (2002) published his work on the biology and natural history of North

American owls. Olsen et al (2002 b) reported a new species of Ninox owl from

Indonesia. Some of the noteworthy web sites for owls of the world are The Owl Pages

(http://www.owlpages.com); World Owl Trust (http://www.owls.org) and Bam Owl

Trust (http://www.bamowltrust.org.uk), amongst others.

Detailed work is done on Bubo bubo the closely allied species to Bubo bengalensis and the various aspects that are studied include ecological studies, vocal behavior, territory, diumal vocal activity, landscape stmcture around nest sites, inter­ relationship between diet, habitat and breeding performance, development of chicks and predispersal behavior of their young. (Penteriani, 1996, Penteriani et al, 2000,

2001, 2002, 2003, 2004, 2005).

1.13 B. Indian perspective

Study of life history, quantification of prey, nesting behaviour, range extension, dietary composition, melanism, rescue and rehabilitation have been done for other species of owls like brama, Bam Owl Tyto alba. Owlet

Athene blewetti (Yosef et al, 2010) and Short-Eared Owl Asio flammeus by several authors (Kumar, 1985; Kanaksabai et al, 1998; Neelanarayanan et al, 1998; Jadhav &

Parasharya, 2003; Kasambe et al, 2004; Pande et al, 2004, 2005a,b,c, 2007;

Ramanujam and Boris, 2004; Neelanarayanan, 2007; Srinivasulu and Srinivasulu,

2007). Interspecific interactions of the critically endangered {Athene blewitti) are recently discussed (Yosef et al, 2010).

The previous work on Bubo bengalensis in India is restricted to Pondicherry region and it deals with some aspects of 'long calls', other vocalizations, communications and displays, and preliminary study on prey and the methods of analyzing rodent prey

10 (Ramanujam, 2001, 2003a, 2004 a, 2006, 2007). Interspecific intimidatory behavior of adult Bubo bengalensis in defence of their nestlings is discussed with respect to behavioral components that differ between sexes and the possible purpose and survival value of this behavior is mentioned (Ramanujam, 2003 b, 2004 b). Some observations on spread wing agonistic displays of Bubo bengalensis are stated

(Ramanujam, 2010). PreUminary work on the development of young of Bubo

bengalensis in and around Puducherry in southern India is published with respect to morphometry, weight and feather molt patterns and supported by photographic data

(Ramanujam amd Murugavel, 2009). It is clearly evident that not much work has been done on several aspects of Indian Eagle Owl Bubo bengalensis and hence requires further detailed and systematic research.

1.14 LACUNAE IN THE PRESENT KNOWLEDGE AND JUSTIFICATION FOR

THE PRESENT STUDY

Owls are raptors and nocturnal predators, have wide home ranges and can be used as bio-indicators to judge sustainable development. Even in modem times owls have not been well studied and especially so in the tropics (Duncan, 2003) including India.

Raptors being at the top of the food chain they are considered as key species in the

conservation and management of environment and hence they play a fiindamental role

in ecological processes (Penteriani et al, 2002).

4 species of owls from India are threatened (BirdLife International, 2001) (Table 1).

The main threats are habitat loss, and competition, diseases, road accidents,

electrocution, and indiscriminate killing due to superstition (Duncan, 2003; Pande et

al, 2005a). In India killing of owls including Bubo bengalensis due to superstitious beliefs is known. Mankind has not always treated owls kindly and anything which might turn the tide slightly in their favour is worthwhile (Hollands, 2004). As a

11 whole, studies in India on owls species are restricted due to their nocturnal habits.

Indian Eagle Owl Bubo bengalensis (Franklin, 1831) is endemic to Indian subcontinent (Pakistan, India and Nepal) (Table 1) (Jathar and Rahmani, 2006) and is not globally threatened (Islam and Rahmani, 2002). (Plate 1). It is also found in the study area including Pune and other areas of state (Ali & Ripley, 1969;

Pande et al, 2003). It has received scant attention and the studies are restricted to south India (Ramanujam, 2001, 2003 a,b, 2004 a,b, 2006, 2007, 2010) and only scattered information in the form of short notes and casual observations is published on its breeding biology, feeding habits, displays and territorial behavior. More information is needed to assess population levels, breeding biology, feeding ecology and its role in ecosystem is not clearly known. Rodents are well known pests of agricultural crops and stored grains and are sources of infection to humans and domestic animals (Prakash and Mathur, 1987) and the role of bio-controllers, such as owls in pest control, has been neglected (Prakash, 1992).

The present study was therefore undertaken to fill these lacunae and to study the ecology of Bubo bengalensis with emphasis on the breeding habits including the development of the young, the foraging habits and to evaluate the role of this species as controller of agricultural crop pest.

1.15 STUDY PLAN

The present study is aimed to document the following parameters related to the Indian

Eagle Owl Bubo bengalensis:

* To present the known owl diversity in the Indian Subcontinent, known distribution of Bubo owls in the world, and briefly summarize the Bubo owls that occur in India and to summarize the , nomenclature and the known status of Bubo bengalensis.

12 * To document the vegetation, crop pattern, climate, topography, biogeographic zones and regions of the study area.

* To give general description of the species, study various body parts such as wing and tail feathers, ear-tufts, ears, eyes and neck, sight, , tarsi, toes and talons, and describe special features like vising clav^s and egg tooth.

* Record bird calls and other non-vocal sounds.

* To study the morphometry of adult Indian Eagle Owl particularly of wings, tail, tarsus, beak, talons, and record their weight.

* Evaluate sexual dimorphism in adult owls with respect to above parameters. Record brood patch and plumage colour in adult owls.

* Perform nest census and evaluate nest spacing.

* Habitat characterization around nest sites by identifying various types of habitats and record habitat utilization of the owls by estimating the relative percent abundance of various habitats, the latter particularly in study area of Saswad and Jejuri environments in Pune district, Maharashtra. (Map 1).

* To study breeding habits under various aspects such as:

- pre-breeding displays and pair formation,

- nesting season, number of nests, nest site, nesting material, change in nest sites, nest size, height, bluff nests, direct and indirect evidence of nesting, nest use and nest hygiene,

- eggs laying dates, clutch size, egg laying interval,

- egg colour, shape, surface and texture, size, shell thickness, and mass,

- parental contribution in nesting with respect to female attentiveness, behavior of male feeding the female,

- incubation period,

13 - loss of egg weight during incubation,

- hatching with respect to piping, hatching time, asynchrony in hatching, hatching interval,

- fledging and nesting success,

- feathering sequence and petrography in chicks, hatchling, pterolysis and apteria, adult behavior and growth of chicks in downy phase and feathering phase,

- growth of young and biometry,

- nest abandonment by chicks prior to actual flight,

- field methods for identifying secondary roosts of juveniles by alarm calls, pellets and focused search,

- nest desertion by female and its consequences,

- first flight of the juvenile,

- necrophagy,

- post-fledging dependence period,

- various kinds of displays such as concealment, territorial, intimidation, epigamic, distraction, food announcement, mantling, solicitation, table-is-reversed, threat, fear, kiwi stance, back revealing, bluff and interactive social,

- floaters,

* To study feeding habits under various aspects such as:

-record components of the diet of adult Indian Eagle Owl,

-seasonality of prey capture,

-month-wise relative abundance of various prey items,

-age analysis of prey items,

-identify and record important agricultural pests in the diet,

-evaluate the role of the Indian Eagle Owl as bio-controller of crop pest,

14 -evaluate correlations between habitat use, diet and breeding success.

* To assess threats and suggest the conservation measures. 1.16 OWL DIVERSITY IN THE INDIAN SUBCONTINENT (Plate 2, 3) Table 1: The table states the scientific name, Family, status whether non-endemic residents or endemic, threat category and whether or not the species is present in the study area (Compiled after Ali and Ripley, 1969; Islam and Rahmani, 2002; Rasmussen and Anderton, 2005; Jathar and Rahmani, 2006).

COMMON NAME GENUS & SPECIES STATUS IF IN STUDY AREA FAMILY : TYTONIDAE Common Bam Owl Tyto alba Non-endemic Present Resident Andaman Bam Owl Tyto deroepstorfii Endemic Eastem Grass Owl Tyto longimembris Non-endemic Resident Phodilus badius Non-endemic Resident Ceylon Owl Phodilus assimilis Non-endemic Resident FAMILY : STRIGIDAE Serendib Scops-Owl Otus thilohoffmanni Endemic Andaman Scops-Owl Otus balli Endemic, Data Deficient Mountain Scops-Owl Otus spilocephalus Non-endemic Resident Pallid Scops-Owl Otus bnicei Non-endemic Present Resident Eurasian Scops-Owl Otus scops Migratory Present Oriental Scops-Owl Otus sunia Non-endemic Present Resident Nicobar Scops-Owl Otus alius Endemic, Near Threatened Indian Scops-Owl Otus bakkamoena Non-endemic Present Resident Collared Scops-Owl Otus lettia Non-endemic Resident Eurasian Eagle Owl Bubo bubo Non-endemic Present Resident Indian Eagle Owl Bubo bengalensis Endemic Dusky Eagle Owl Bubo coromandus Non-endemic Resident Forest Eagle Owl Bubo nipalensis Non-endemic Resident Brown Owl Bubo zeylonensis Non-endemic Present Resident Tawny Buboflavipes Non-endemic Resident Duffy Fish Owl Ketupa ketupa Non-endemic Resident Nyctea scandiaca Migratory Mottled Wood-Owl Strix ocellata Non-endemic Present Resident Brown Wood-Owl Strix leptogrammica Non-endemic Present Resident Spotted Wood-Owl Strix seloputo Non-endemic Resident Himalayan Wood- Strix nivicola Non-endemic Owl Resident

16 COMMON NAME GENUS & SPECIES STATUS IF IN STUDY AREA Tawny Owl Strix aluco Non-endemic Resident Hume's Wood-Owl Strix butleri Non-endemic Resident Glaucidium brodiei Non-endemic Resident Glaucidium radiatum Non-endemic Resident Chestnut-backed Glaucidium Non-endemic Owlet castanonatum Resident Glaucidium cuculoides Non-endemic Resident Athene noctua Non-endemic Resident Spotted Owlet Athene brama Non-endemic Present Resident Forest Owlet Heteroglaux blewitti Endemic, Critical Boreal Owl A egolius funereus Non-endemic Resident Brown Hawk-Owl Ninox scutulata Non-endemic Present Resident Hume's Hawk-Owl Ninox obscura Endemic Andaman Hawk-Owl Ninox affinis Endemic, Near Threatened Northern Long-eared Asia otus Migratory Owl Short-eared Owl Asio flammeus Migratory Present

17 1.17 Bubo OWLS IN THE WORLD: A BRIEF SUMMARY (Plate 2) Table 2: 23 species recorded from different parts of the world are listed below. The name of the species, the common name and the distribution are mentioned. The species in bold type occur in India:

Common Name Owl species Distribution Eurasian Eagle Owl Bubo bubo Eurasia except peninsular India. Indian Eagle Owl Bubo bengalensis Peninsular India and the Indian subcontinent, Forest Eagle Owl Bubo nipalensis Indian subcontinent, SW Asia. Dusky Eagle Owl Bubo coromandus Indian subcontinent, , . Philippine Eagle Owl Bubo philippensis . Barred Eagle Owl Bubo sumatranus SE Asia. Blakiston's Eagle Owl Bubo blakistoni Far East Asia and Russia. Phroah Eagle Owl Bubo ascalaphus. North Africa. Cape Eagle Owl Bubo capensis SE Africa. Spotted Eagle Owl Bubo africanus Central and S. Africa. Greyish Eagle Owl Bubo cinerascens C. Africa. Eraser's Eagle Owl Bubo poensis Central and W. Africa. Usumbara Eagle Owl Bubo vosseleri Tanzania Malawi Mountains. Shelly's Eagle Owl Bubo shellevi West and Central Africa. Verreaux's Eagle Owl Bubo lacteus Central and S. Africa. Akun Eagle Owl Bubo leucosticus Central and West Africa. Great Homed Owl Bubo virginianus North and South America. Magellanic Owl Bubo magellanius West coast of South America. Bubo zeylonesis SW and parts of SE Asia. Pel's Bubo peli Central and South Africa. Snow Owl Bubo scandiaca Boreal circumpolar. Eurasian Eagle Owl Bubo interpositus Turkey, Russia Bubo flavipes N. India, W. , N. Burma,

(After Wink and Heidrich, 1999, based on cytochrome b mitochondrial DNA sequencing of owls.)

18 1.18 Bubo OWLS IN INDIA: A BRIEF SUMMARY Table 3: Distribution, status, habitat, dominant vegetation, size, plumage, call, morphometry, common pellet content, nest site and eggs for six species of Bubo owls occurring in India are briefly tabulated, (vide Ali and Ripley, 1969).

B. bubo B. bengalensis B. nipalensis B.coromandus B. zeylonesis B. flavipes Distribution N.India, Peninsula Lower Subcontinent Subcontinent, N. India, outer Eurasia Himalayas south of Peninsula & Himalayas Himalayas Himalayas Status Resident Resident Resident Resident Resident Resident Habitat Montane, Open, dry, semi- E. & W. Ghats Plains Plains and hills Hills arid Vegetation Coniferous Scrub Ev. Gr. Forests Groves, near Near water in Near water in Terrai, Duars, habitation wooded areas forested areas Sholas Size 66 cm 56 cm 63 cm 58 cm 56 cm 61 cm

Plumage Brown, Tawny brown Tawny, white, Throat white Brown-grey Brown, lacy bars streaked and streaked chest dark barred Fine streaks and streaks Throat spotted belly. Throat white dark Call Oo-woo, Ghu, ghu, ghoo, Deep moan, Wo-wo-wo- Bo Boom-o, Whoo-hoot, wooo, ghoo. ghug hoot. A loud wooo boom-o-boom. Moans Durgoon, shriek durgoon Wing cord 44.0^7.0 cm 36.4-42.5 cm 425^70 cm 380-415 cm 37.9^4.3 cm 41.0-45.5 cm

Tarsus 7.7-8.1 cm 69-76cm 6.0-6.2 cm 5.5-7.0 cm 7.1-9.0 cm 60-67 cm

Feathered Feathered Feathered Party feathered Not feathered Not feathered Tail 26.0-31.0 cm 18,5-22.7 cm 22.9-25.0 cm 19.8-21.0 cm 186-210 cm 21.5-22.7 cm

Beak 4.5-4.7 cm 'i.lA.l cm 5.2-5.4 cm 4.2-4.9 cm 4.9-5.4 cm 4.6-5.0 cm

Iris Golden Yellow-orange Hazel brown Bright yellow Golden yellow Yellow yellow

Ear tufts Erect, Black Erect, black and Slanting, Grey Oblique Horizontal Horizontal

PeUets Rodents Rodents Fowl, rodent. , rodents Fish, Fish, crab

Nest On ground or On ground or on On tree On tree In In tree hollow on ledge ledge

Eggs Two-five Two to five One One to two One to two One to two

(Key to abbreviations: B stands for the genus Bubo. N for North; E for Eastern and W for Western; Ev. Gr. for Evergreen).

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