THE BIRDS OF NORTHERN THAILAND 47 



Family THRESKIORNITHIDAE 



PSEUDIBIS PAPILLOSA DAVISONI (Hume) 



Davison's Black Ibis 



Geronticus Davisoni Hume, Stray Feathers, vol. 3, 1875, p. 300 ("on the banks 

 of the Pakchan Estuary in the extreme south of the Tenasserim Provinces"). 



The black ibis is confined to Chiang Rai Province, and the only 

 northern specimen yet known is a male collected by me at Chiang Saen 

 Kao, January 12, 1937. This was one of a flock of five or six birds that 

 occurred upon a large sandbar in the Mae Khong. They were ex- 

 ceedingly wild, and it was possible to take an example only by stalking 

 them from a boat at nightfall. 



Ibises in general may be known from herons by their long, sickle- 

 shaped bill. The present species has the head naked, black in color 

 except for a pale blue area on the nape; the plumage black, glossed 

 purple and green, with the exception of a white patch on the inner 

 lesser wing coverts ; the feet red. 



Order ANSERIFORMES 

 Family ANATIDAE 



DENDROCYGNA JAVANICA (Horsfield) 



Javanese Whistling Teal 



Anas Javanica Horsfield, Trans. Linn. Soc. London, vol. 13, 1821, pp. 199-200 



(Java). 

 Dendrocygna javanica, Gvxdenstolpe, Kungl. Svenska Vet.-Akad. Handl., 1916, 



p. 135 (Chiang Rai) ; Ibis, 1920, p. 773 ("Throughout the whole country").— 



Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 1931, p. 174 (Chiang Mai) ; 



1936, pp. 74, 131-132 (Chiang Mai, Ban Nong Khiat, Ban Tha Nong Luang) . 



The whistling teal is by far the commonest and best known of Thai 

 ducks and is present throughout the year in all our provinces. During 

 the rains it abounds everywhere, on the marshes and at pools in the 

 ricefields ; in the dry months it congregates, often in vast numbers, at 

 woodland ponds and in the swamps. Gyldenstolpe found it abun- 

 dant at Chiang Rai in August 1914 ; I considered it abundant at Chiang 

 Mai from June 28 (1930) to September 19 (1931) and locally common 

 during the rest of the year. I saw it in numbers at Phayao in August 

 1929 and at Muang Fang in July 1936. It was locally common at 

 Chom Thong in January 1936. In December 1935 I observed a flock 

 of about 100 at Nong Khiat and over 1,000 at Nong Luang. The 

 "millions of ducks" reported to occur in winter in Chiang Rai Province 

 are largely of this species. 



