The animals were looking to dry off and warm up after the first monsoon rains hit India's capital, and their appearance on the runway forced authorities to stop planes from taking off and landing, Indira Gandhi International Airport spokesman Arun Arora said in a statement.
Animal welfare authorities cleared the runway of wildlife, including monitor lizards that measured as long as 2-3 feet, Arora said.
Arora didn't say how many flights were delayed. The Hindustan Times newspaper said about 100 flights were affected.
In the monsoon season, which runs from June to September, heavy rains routinely delay flights all over India.
