On 13 November 2021 at approximately 1300h, Dave was walking near Block 509 Bishan Street 11 when he noticed some crows perched restlessly in the vicinity. A flock of about 10 crows (probably Corvus splendens) started mobbing a barn owl (Tyto alba) in flight. The owl landed on the roof surrounded by the attacking crows. The crows cawed loudly and encircled the owl. The aggressors looked like they were going to attack the owl. The scene was very tense and many curious people rushed to the scene of attack. The crows then backed off to the higher roof on their own accord. The attacking bird mob was still agitated while on the higher roof and the members looked like they were ready to attack again.
The owl then flew to a nearby tree and the crows went in pursuit of the owl again. The crows attacked the owl and then flew off to perch on nearby branches and signboards.
Video of the owl sitting on the roof after the first attack.
Dave had to hurry off to run errands and did not stay around to witness the eventual sequence of events or what the owl did after this.
Video and all photo credits: Dave