The Common Buzzard (Buteo buteo) is a raptor with a wide range and some subspecies are split by some author as separate species.
There are 11 subspecies, being found across Eurasia, and wintering in Africa and Southeast Asia [1]. The subspecies possible in Singapore are Eastern Buzzard (B. b. japonicus), Steppe Buzzard (B. b. vulpinus) and Himalayan Buzzard (B. b. refectus).
In Singapore, it is listed as an uncommon winter visitor. Early/late dates: 18Oct/18Apr
It preys mainly on small mammals.
It mainly inhabits open areas.
It has been sighted at Airport Road, Bidadari, Bukit Batok, Changi, Holland Road, Jurong Lake, Lorong Halus, Kent Ridge, Sembawang, Sentosa, Tuas.
Reference:
[1] https://www.birds.cornell.edu/clementschecklist/