The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amo...The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand （350-2450 m asl; 29N）, Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness （14.35 vs 8.69）, higher species diversity （Shannon＇s index 4.00 vs 3.54）, higher evenness （0.838 vs 0.811） and more rare species （17 vs 5） as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness （BSR） varied considerably among study areas （91 to 113 species）, was high- est （113 species） at mid elevation （1450-1700 m asl） and decreased （22 species） at high elevation （1900-2450 m asl）. It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 （3）： 318-329,2011].展开更多
To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages...To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages： pre-removal （pairs were present on their respective territories）, removal （females were experimentally removed）, and returned （females were released into the focal pairs＇ territories）. Dawn bout length, song rate, song complexity, percentage performance time, song perch height, and distance of singing location to territory boundary were measured for each male during each experimental stage. We did not find an effect of mate removal on any dawn song characteristics of male pied bush chats suggesting that the presence or absence of a mate does not influence male dawn singing behaviour. Our findings further suggest that males use dawn chorus to mediate social relationships with neighbouring males to proclaim an established territory展开更多
文摘The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand （350-2450 m asl; 29N）, Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness （14.35 vs 8.69）, higher species diversity （Shannon＇s index 4.00 vs 3.54）, higher evenness （0.838 vs 0.811） and more rare species （17 vs 5） as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness （BSR） varied considerably among study areas （91 to 113 species）, was high- est （113 species） at mid elevation （1450-1700 m asl） and decreased （22 species） at high elevation （1900-2450 m asl）. It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 （3）： 318-329,2011].
文摘To determine the influence of pairing status on dawn singing behaviour in pied bush chats Saxicola caprata, we conducted mate removal experiments across eight territories. The experiment was divided into three stages： pre-removal （pairs were present on their respective territories）, removal （females were experimentally removed）, and returned （females were released into the focal pairs＇ territories）. Dawn bout length, song rate, song complexity, percentage performance time, song perch height, and distance of singing location to territory boundary were measured for each male during each experimental stage. We did not find an effect of mate removal on any dawn song characteristics of male pied bush chats suggesting that the presence or absence of a mate does not influence male dawn singing behaviour. Our findings further suggest that males use dawn chorus to mediate social relationships with neighbouring males to proclaim an established territory
