Karakteristik Sarang dan Keberhasilan Berbiak Kuntul Besar (Egretta alba) dan Cangak Abu (Ardea cinerea) di Areal Breeding Site Desa Tanjung Rejo

Abstract

The nest characteristic and breeding success of Great Egret (Egretta alba) and Grey Heron (Ardea cinerea) in the fishpond area of Tanjung Rejo, Sumatera Utara has been studied from October 2014 to January 2015. The method used in this study was observation. The research revealed that Grey Heron chose 3 kinds of tree to build 5 nests (R. mucronata, A. Officinalis, S. Alba) with 6,5-9 m. While the dominant nest material were 30,01-35,00 (13%) of height and 30,01-35,00 (13%) of diameter. For Great Egret used 2 kinds of tree for nesting (R. mucronata & C. tagal) with 3,8-5,4 m. The dominant nest material were 20,01-25,00 (23,38%) of height and 0,21-0,4 (41,12%) of diameter. Both species have eggs ratio varies from 1,2:1 until 1,4:1 cm and it was classified into type VI. For egg laying, it ranges from 2 until 4 days for Grey Heron and 2 until 6 days for Great Egret. The optimum incubation were 26 until 29 days for Grey Heron, 23 until 25 days for Great Egret. The hatching success of Great Egret was (100%) and this number was higher than the hatching success rate which was (82,35%) for Grey Heron.