The Bird of Kildarby is a giant monstrous bird that was the pet of Lord Kildarby.
Lord Kildarby made a deal with the Ghostbusters that if they defeated the Bird of Kildarby, he and his army would leave their castle and Manhattan forever. The team agreed and discovered the true danger presented by the Bird. They made a strategic retreat to Ecto-1 and quickly brainstormed a way to survive. The Ghostbusters managed to trap the bird by connecting two Traps to the Containment Unit and sending it in. Lord Kildarby and his army had nowhere to go so the Ghostbusters allowed them to stay if they tone down their habits of haunting the place during the day.
Tobin's Spirit Guide
The Bird of Kildarby has the power of flight and possesses above average strength. While in flight, it is able to tear off the roof of Ecto-1 and takes only 29.4 seconds to realign and attack again.  It also was able to crash through the wall of the Firehouse without taking any harm.
For an unspecified reason, the Bird of Kildarby was stated to be too large for the traps. It was confined in three Proton Streams and could only be captured indefinitely by the power of the Containment Unit.
- The Bird is referenced in What in Samhain Just Happened?! on page nine. A bust of the creature can be seen behind Janine Melnitz.
- The bird is similar in physical description, behavior, and place of origin to the Adar Llwch Gwin of Welsh legend.
- "The Bird of Kildarby"
- "The Grundel"