author(s)
AK Kataria, N Kataria, RK Pareek, Akriti, Diwakar, Sunita Choudhary and RN Kumawat

abstract
The present exploration appraised the effect of temperature humidity index on migration of Himalayan griffon (Gyps himalayensis) at Jorbeer Conservation Reserve, Bikaner, Rajasthan, India (JCRBRI) during a period from May 2015 to April 2018. The population of griffons was recorded along with environmental temperature and humidity on 1^st and 15^th day of every month from May 2015 to March 2016, and 1^st, 10^th and 20^th day of every month from April 2016 to April 2018. The Himalayan Griffon established their presence from the month of November 2015 in the duration of 2015-16, October 2016 in the duration of 2016-17 and October 2017 in the duration of 2017-18. It was observed that in each year of study, birds marked their disappearance from May to September in absolute terms. In year 2015-16, a maximum number of 60 Himalayan Griffons was observed on February 15, 2016. In year 2016-17, a maximum number of 30 birds was observed in the months of January and February, 2017. In year 2017-18, a maximum number of 120 birds was observed on 10^th December and 20^th December 2017, 1^st January and 10^th January 2018. During the disappearance period (from May 2015 to October 2015) of birds, the THI_max values oscillated between 80.66 and 86.89. The period (from November 2015 to March 2016) when birds were observed in the reserve, the THI_max values were either 77.03 or lower. The result of present endeavour exhibited precedent of wintering for Himalayan griffon at the JCRBRI.