关键词: 短嘴金丝燕, 繁殖生物学, 环志, 壶瓶山保护区

Abstract

From April 1994 to November 2007, we studied the breeding biology of the Himalayan swiftlet (Aerodramus brevirostris innominata) based on field investigations, behavior observations, and bird bandings in the Shenjing Cave of Hupingshan National Nature Reserve, Hunan Province. Overall, we found a total breeding population of 2,000 swiftlets in the cave. The Himilayan swiftlet is a summer migrant in the area which arrives in early April and departs in early November. This species is monogamous with a sex ratio of about 1:1, and reaches sexual maturity at one year of age. Birds nested in dark caves, with nests primarily composed of saliva and mosses. Birds took 60 days to finish nest construction, and old nests from previous years were fully reused. We found that egg laying began after nest construction and peaked in June. In most cases, two eggs were found in each nest, while occasionally one egg. Both males and females were involved in incubation, but females invested relatively more time. The incubating temperature, duration, and hatching success were 37.3 ± 1.0℃, 27.9 ± 3.4 days, and 71.4%, respectively. Nestlings were altricial, and were fed mainly by males for about 27 days with insects, which were the same as adults’ diet. They spent another 3 or 4 days to learn to fly in the cave before fledgling the nest. Fledglings gained substantial weight, which tended to be greater total weight than the parents, before leaving the nest. We observed a concordant decrease in weight upon reaching sexual maturity. Primary threats to Himalayan swiftlets in China include disturbance to breeding activities resulting from tourism development and illegal nest-collection. We suggest that authorities halt development of caves and surrounding areas and ban the illegal nests collection.

Key words: Himalayan swiftlets, breeding biology, banding, Hupingshan National Nature Reserve