What time period were miners using parakeets for gas detectors?

Miners used parakeets as gas detectors primarily during the early to mid-20th century, particularly from the 1910s to the 1980s. The birds were sensitive to toxic gases such as carbon monoxide and would show signs of distress or die before the gas levels became dangerous for humans. This practice was eventually phased out with the advent of more reliable and advanced gas detection technology.