In order to study the home range of the red-tongue viper snake (Gloydis ussuriensis) and the short-tailed viper snake
(Gloydius saxatilis) belonging to the viperidae of squamat in Korea, we implanted radio-transmitters which were weighed
less than 5% of individual mass in them and traced their location by radio-tracking. Surgeries for transmitter insertion were
performed on 5 red-tongue viper snakes and 6 short-tailed viper snakes (total 11 individuals) and the average ratio of
transmitter mass to body mass were 4.2% and 2.2%, respectively. After radio-transmitter implantation, all short-tailed viper
snakes survived but 4 out of 5 red-tongue viper snakes did not survive during the convalescence stage, showing only 20%
of survival rate. The results suggest that the ratio of transmitter mass to body mass should be less than 3.6% at least in
these species, although previous studies have recommended various ranges from 1% to 7% as the acceptable ratios.