Distribution records and extended range of the Sri Lanka Frogmouth Batrachostomus moniliger ( Aves : Caprimulgiformes : Podargidae ) in the Western Ghats : a review from 1862 to 2015

The Sri Lanka Frogmouth (or Ceylon Frogmouth) Batrachostomus moniliger is an endemic resident bird confined to the evergreen and secondary forests of Sri Lanka and the Western Ghats of India. The earlier distribution range of the Frogmouth was from the Uttara Kannada District of Karnataka to the southern tip of India and most of Sri Lanka. Recently, the range has been extended further north to Goa and up to Mumbai in Maharashtra. A number of observations summarized into 202 distributional records (published reports and records uploaded to eBird basic data set, Oriental Bird Images, and GBIF.org from the years 1862 to 2015) of the Frogmouth have been tabulated with its maps, and reviewed for their state-wise distribution records. The need of undertaking surveys to fill up the gaps in their distribution range as well as any further northward extension till the culmination of the Western Ghats has been discussed. It is urged that taxonomical and molecular phylogenetic studies are required to be carried out in different populations of Frogmouths across the entire range.


INTRODUCTION
The frogmouths are a group of stocky nocturnal birds distributed across Oriental and Australasian Regions (Ali 1949;Gruson 1976).The 14 known species of frogmouths belong to the family Podargidae constituting three genera -Rigidipenna, Podargus and Batrachostomus (Holyoak 2016).One of these, the Sri Lanka Frogmouth (or Ceylon Frogmouth) Batrachostomus moniliger Blyth, 1849 (Images 1 & 2) is of Indochinese affinity (Ripley 1959).It is a medium-sized sexually dichromatic bird with a largehead, hooked bill and large forward-facing yellow eyes.It is arboreal, nocturnal, shy and seldom seen during the day time.Also apparently not very vocal during the day, hence possibly less rare than it appears.It is a resident and locally common bird confined to dense evergreen, humid primary and secondary forest (adjacent degraded forest), and thick bamboo; but usually avoids plantations and disturbed forests.The bird is insectivorous in habit, its diet consisting of beetles, grasshoppers and moths; the breeding season is mainly from January to April but continues till October.The nest is placed in the fork of a small tree or horizontal branches 2m and above from the ground.Only one egg is laid which is white and elliptical.Both sexes share incubating duties (Ali & Whistler 1936;Ali 1969Ali , 1999;;Marshall 1978;Ali & Ripley 1983;Cleere & Nurney 1998;Baskaran 1999;Holyoak 1999Holyoak , 2001;;Cleere 2010;Sashikumar et al. 2011;Rasmussen & Anderton 2012;Grimmett et al. 2013;Holyoak & Kirwan 2016).It is a bird endemic to the South Asian mainland and Sri Lanka (Jathar & Rahmani 2006)

MATERIALS AND METHODS
The number of observations summarized into 202 distribution records of Sri Lanka Frogmouth, from 1862 to 2015, from all the states in its distribution range falling under the Western Ghats, India have been reviewed in this paper.Out of these records 122 are from the published literature, while the remaining sightings of the frogmouths are from the documented observations by various bird watchers, nature watch groups uploaded to eBird Basic Dataset (2015) and GBIF.org (2016), as well as from the photographs uploaded on the Oriental Bird Images (2015) between 2001 and 2015.
Since 2001 technological advancements such as eBird and other internet platforms have transformed the way bird watchers have recorded their observations.Hence, we have considered the previous distribution records of frogmouths from the year 1862 to 2000 and recent records from the year 2001 to 2015.While reviewing the records, we considered the locality along with geographical co-ordinates, date of sightings and general observations on the frogmouths to prepare the table.We acknowledge in some cases the geographical coordinates associated with the observational record have the limitation of not being the exact location of the observation.
Recent sightings of the Frogmouth have been recorded by various researchers (Eldhose 2001a & b;Sashikumar & Palot 2005;Praveen & Nameer 2007, 2008;Sashikumar et al. 2010Sashikumar et al. , 2011Sashikumar et al. , 2014;;Praveen 2015) and nature watch groups between 2003 and 2015.The observations by these nature watch groups were sourced from the eBird Basic Dataset (2015) and GBIF.org (2016) with photographs uploaded on Oriental Bird Images (2015).Further, Table 1 indicates that most of these sightings were from the bordering areas of Idukki and Ernakulam districts and a few sightings in other districts of the state, such as Thiruvananthapuram, Kollam, Pathanamthitta, Thrissur, Palakkad, Malappuram, Kozhikode, Wayanad, Kannur, and Kasaragod except for the district of Alappuzha.

Tamil Nadu
There are seven previous sightings of the Frogmouth from Anaimalai Hills of Coimbatore District between 1991 and 1993 (Kannan 1993(Kannan , 1994(Kannan a,b, 1998) ) and further, according to him these constitute the first record of the species from Tamil Nadu.However, there are a few records of some specimens collected from the districts of Madurai in 1986 and Tirunelveli in 1992 (Dutta 2009).
It was noticed that the previous and recent sightings of these birds from Coimbatore District are mostly from Anaimalai Hill ranges.Santharam (2005) suggested that the Frogmouth is a locally threatened bird of the state and are in need of conservation efforts on priority.

Karnataka
The most previous records of Sri Lanka frogmouths were from various places in Uttara Kannada District (Davidson 1895(Davidson , 1898)).Thereafter, eggs, nest and nestlings were collected by T.R. Bell during or before 1927 from Karwar (now Uttara Kannada) (Baker 1927(Baker , 1934)).Koelz (1942) surveyed birds in Londa neighbourhood and from Uttara Kannada during 1938and Ali (1942-1943) in Mysore (now Karnataka) state including Bababudan Hills and forests adjoining Coorg (now Kodagu), but they did not record any Frogmouth from these areas.After a gap of about 40 to 45 years, the birds have been again sighted from 1983 to '85 in Uttar Kannada District by Daniels (1984Daniels ( , 1986) ) and Borges (1986).There are some records of specimens collected from Kodagu District and Jog Falls, Shimoga District in 1977 (Dutta 2009).
Recently, Kumara & Singh (2006) and others have sighted a number of Frogmouths in different areas of the Western Ghats between 2001 and 2003.Barve (2010) and Barve & Warrier (2013) have sighted these birds commonly in Sharavathy Valley of Udupi District.Beside this, the birds were sighted by a number of observers in Kodagu, Chikmagalur, Udupi, Shimoga and Uttara Kannada districts from 2005 to 2015 (eBird Basic Dataset 2015; Oriental Bird Images 2015) (Table 1).

Goa
There were a number of studies carried out on the birds of Goa (Grubh & Ali 1976;Abdulali 1980; Rane

CONCLUSION
The earlier northernmost distribution range of the Sri Lanka Frogmouth was up to Uttar Kannada, Karnataka starting with the records from around 1898 (Davidson 1898).The recent records such as the one by Holt in Bondla Wildlife Sanctuary, North Goa District, in 1996 (Lainer 2004) extended the range further northwards to Goa.The continued northward movement of the bird into the state of Maharashtra was recorded in Radhanagari Wildlife Sanctuary, Kolhapur District in 1998 (Giri 2002), Phansad Wildlife Sanctuary, Raigad District in 2009 (Prashanth 2009;Kasambe 2012) and Sanjay Gandhi National Park near Mumbai in 2011 (Kasambe 2012).Further, Kasambe (2012) speculated whether it extends till the Dang District in Gujarat where the Western Ghats culminates.There is one record of Hodgson's Frogmouth (Batrachostomus hodgsoni) (Pilo et al. 1996) from Shoolpaneshwar Wildlife Sanctuary in Gujarat but not that of Sri Lanka Frogmouth.This record however seems doubtful and requires further corroboration.
Until 2000 the observation records of the Sri Lanka Frogmouth were patchy and there were huge gaps in their distribution range along the Western Ghats.Now many gaps have been filled up because of the recent records and hence, it shows a more or less continuous distribution in the various states (particularly in Kerala and Goa) (Fig. 2).Some gaps still remain (can be viewed at https://goo.gl/5KU9lw)which need to be surveyed properly for presence of the Sri Lanka Frogmouth, if any, in the states given below.Some of these gaps exist possibly because of unsuitable forest habitats, agricultural lands, tea estates, urbanization etc. resulting in less possibility of their occurrence.

Kerala
i.
Between north of Thenmala, Kollam District to Thrivani, Pathanamthitta District an aerial gap of about 40km particularly around Rani Forest Division, Thannithodu, and Aruvappulam.
ii. Between Eravikulam National Park and Wallardie, Idukki District an aerial gap of about 55km particularly around Devikulum, Kannathadu, Idukki Wildlife Sanctuary, Cardomom Hills and Ayyappacoil.

Tamil
ix.Some parts of the districts such as Mysore, Hassan, Dakshina Kannada, Dharwad and Belgaum falling in the Western Ghats range.

Goa
x.More or less continuous distribution in the state with no major gaps.
xiv. Between Kaas, Satara District and Chandoli, Sangli District an aerial gap of about 60km particularly around Koyna Reservoir, Nawaja, Chandel and around Dikshi Reservoir.
xvi. Between Chavani and Bhira, Raigad District, R e v fi ew D fi s tt r fi b u tt fi o n r e c o r d s a n d e x tt e n d e d r a n g e o f tt h e S r fi L a n k a F r o gm o u tt h B a tt r a c h o s tt om u s m o n fi l fi g e r ( A v e s : C a p r fim u l g fi f o rm e s : P o d a r g fi d a e ) fi n tt h e W e s tt e r n G h a tt s : a r e v fi ew f r om 1 8 6 2 tt o 2 0 1 5 T h r e a tt e n e d T a x a A l l a r fi c l e s p u b l fi s h e d fi n tt h e J o u r n a l o f T h r e a tt e n e d T a x a a r e r e g fi s tt e r e d u n d e r C r e a fi v e C omm o n s A tt r fi b u fi o n 4 .0 I n tt e r n afi o n a l L fi c e n s e u n l e s s o tt h e rw fi s e m e n fi o n e d .J o T T a l l ow s u n r e s tt r fi c tt e d u s e o f a r fi c l e s fi n a n y m e d fi um , r e p r o d u c fi o n a n d d fi s tt r fi b u fi o n b y p r o v fi d fi n g a d e q u a tt e c r e d fi tt tt o tt h e a u tt h o r s a n d tt h e s o u r c e o f p u b l fi c a fi o n .O P E N A C C E S S P a r tt n e r www .tt h r e a tt e n e d tt a x a .o r g I S S N 0 9 7 4 -7 9 0 7 ( O n l fi n e ) | I S S N 0 9 7 4 -7 8 9 3 ( P r fi n tt ) T h e fi n tt e r n a fi o n a l j o u r n a l o f c o n s e r v a fi o n a n d tt a x o n om y J o u r n a l o f T h r e a tt e n e d T a x a P u b l fi s h e r / H o s tt F o r F o c u s , S c o p e , A fim s , P o l fi c fi e s a n d G u fi d e l fi n e s v fi s fi tt h tt p : / / tt h r e a tt e n e d tt a x a .o r g / A b o u tt _ J o T T .a s p F o r A r fi c l e S u bm fi s s fi o n G u fi d e l fi n e s v fi s fi tt h tt p : / / tt h r e a tt e n e d tt a x a .o r g / S u bm fi s s fi o n _ G u fi d e l fi n e s .a s p F o r P o l fi c fi e s a g a fi n s tt S c fi e n fi fi c M fi s c o n d u c tt v fi s fi tt h tt p : / / tt h r e a tt e n e d tt a x a .o r g / J o T T _ P o l fi c y _ a g a fi n s tt _ S c fi e n fi fi c _M fi s c o n d u c tt .a s p F o r r e p r fi n tt s c o n tt a c tt < fi n f o@ tt h r e a tt e n e d tt a x a .o r g > and has been categorized as Least Concern in the IUCN Red List (BirdLife International 2015).It is listed in Schedule I, Part III (Birds) of the Indian Wildlife (Protection) Act, 1972 (as amended up to 2006).

Figure 1 .
Figure 1.Distribution of Sri Lanka Frogmouth in India and Sri Lanka recorded Sri Lanka Frogmouth for the first time in the state of Maharashtra from Kolhapur District in November 1998.Thereafter, Kasambe (2012) sighted the Frogmouth in Mumbai during March 2011.Recent sightings of these birds are recorded in Raigad District (Prashanth 2009; Oriental Bird Images 2015) and in Sindhudurg District (eBird Basic Dataset 2015).From 2014 to 2015, Sayyed & Mahabal (2016) recorded the Frogmouth in the area between Kolhapur and Mumbai, particularly in the districts of Sindhudurg, Ratnagiri, Sangli, Satara and Raigad falling under the Western Ghats, and filled up a big gap in its distribution range.

Figure 2 .
Figure 2. Distribution records of Sri Lanka Frogmouth in Western Ghats, India

Sri Lanka Frogmouth in Western Ghats: A review Mahabal et al.
Nadu iv.Western parts of Theni and Dindigul districts, although falling in the Western Ghats particularly the Palni Hills including Kallar Reserve Forest, Kodaikanal, Poombarai and Kookal.Kodagu District an aerial gap of about 40km, particularly around the Greater Talacauvery National Park, Madikeri, Bettaphur, Nelaji, Naladi.vi.Between Karkala, Udupi District and Pushpagiri-Bisale area in Western Ghats an aerial gap of about 80km particularly around Mullodi, Kottigehara, Dharmasthala, Byrapura Estate.vii.Between Sharavathy Wildlife Sanctuary and Someshwara Wildlife Sanctuary, Udupi District an aerial gap of about 60km particularly around Hosanagar, Mookambika Wildlife Sanctuary, Hulikal and around Mani Reservoir.