Purplerumped sunbird Nectarinia zeylonica (Linn.): a new record for Assam

1 Pages·1991·0.63 MB·

by  A Choudhury

114 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. 88
16. PURPLERUMPED SUNBIRD NECTARINIA ZEYLONICA (LINN.):
A NEW RECORD FOR ASSAM
The purplerumpcd sunbird Nectarinia zeylonica area where the purplerumpcd sunbird is found is southern
was hitherto unrecorded in Assam. At about 1415 hrs on Bangladesh (up to Dhaka in the north) and extending to
19 April 1988, 1 saw one male of this species in the gar- Arakan. The species seems to have been overlooked on
den of the local sub-divisional veterinary office com- many occasions. It is apparently an uncommon resident
pound, located in theheartofHailakandi town in southern of the Barak valley districts of Cachar and Karimganj.
Cachar district.
According to the HANDBOOK OFTHEBIRDS OFINDIA
ANWARUDDIN CHOUDHURY
AND PAKISTAN (Ali, S. and Ripley, S.D. 1983) the nearest March 31 1989
,
HYBRID HOUSE SPARROW-TREE SPARROW FROM ARUNACHAL PRADESH
17.
On3 January 1981, the senior author collected three Plumage characters that agree with pure montanus
Passer specimens atDeban, 22km eastofMiao,Tirapdis- are: (1) the twin buff-white wing-bars (lacking the
trict, Arunachal Pradesh (altitude 330 m). These three prominent anterior white wing-bar of domesticus)', (2)
specimens were tentatively identified as tree sparrows chin stripe and bib are narrow, short, and not much ex-
Passer montanus hepaticus, and deposited in the collec- pandedposteriorly (muchmoreprominentindorneslicus)',
tion of the National Museum of Natural History, Smith- (3) abdomen dirty buff (not clear pale buff as in domes-
sonianInstitution, Washington, D.C. Later, whilecarrying ticus)', (4) rump buff-brown (not pale buff-grey as in
out a complete review of our collections of birds from domesticus).
Arunachal Pradesh, we found that one of the Passer Outside of the Indian region, the two species have
specimens (USNM No. 585161) appears to be a hybrid been reported to hybridize in a few localities (Albrecht
montanusx dorneslicus.This is ofinterestfor tworeasons. 1983, Hume 1983, Goselj 1985); and yet P. domesticus is
Itapparently is thefirstevidenceofhybridization between much better known to interbreed with the Spanish spar-
the house sparrow and the tree sparrow in India (Baker row P. hispaniolensis, with which it also co-occurs over a
1926, Ali and Ripley 1987), and it may represent the first considerable range (Vaurie 1959).
specimen record proving the occurrence ofdorneslicus in Although the geographic ranges of house and tree
the hills of Arunachal Pradesh (see Ripley 1982: 537). sparrows generally meet all along the Himalayan cordil-
The putative hybrid is a male (testes not enlarged) lera, only in a few sites do the two exhibit true within-site
in adult, non-breeding plumage, with measurements (in sympatry. The two sort out by habitat, the tree sparrow
mm) as follows: wing chord 72; wing arc 74; bill from generally occurring at higher altitudes, and in less urban
skull 14; bill from feathering 11 tail 52; tarsus 18; weight locales. Krishna Raju and Price (1973) found both house
;
18 g. Mostofthesemeasurements would accord well with and tree sparrows inhabiting villages in the Chintapalle
therangeofmeasurementsofeitherspecies,butthe weight plateau ofthe Eastern Ghats. Price (1979) reported anun-
agrees more closely to montanus, as does the short tarsus. confirmed observation of a hybrid at the village of Bus-
This specimen shows five characters that agree with salkort. Weshouldnotethatoursearch forthepopulations
montanus, one character that agrees with dorneslicus and of montanus on this same plateau in 1985 failed (Ripley
three characters that are intermediate between the two el al. 1988). Has the house sparrow completely replaced
presumed parental types. the relict population of the tree sparrow in the Eastern
The single, but very prominent, pure dorneslicus Ghats?
character is the buff-grey cap and nape, indistinguishable Deban, Arunachal Pradesh, where our hybrid
from typical Passer domesticus indieus the population specimen was taken, lies al the foot of the Dapha Bum
recorded from north-eastern India. range, at an altitude that may be low for montanus and at
Plumagecharacters intermediatebetweenmontanus the upper edge of the altitudinal range ofdomesticus. We
and dorneslicus are: (1) brown lores contrasting with the presume that hybrids between these two species will be
grey cap (entire cap grey in dorneslicus, entire cap brown foundby futureornithologists who focuson thenon-forest
in montanus); (2) cheek spot is an apparent, but obsolete, avifauna of the hills ofnorth-eastern India.
dark grey smudge (entirely absent in dorneslicus', and a
well-delineated black spot in montanus)', and (3) chestnut
streaking on mantle is apparent (much more dominant in S. DILLON RIPLEY
dorneslicus, absent in montanus.) March 5, 1989 BRUCE M. BEEHLER