Garth: We're at university together doxycycline order online We managed to find “our boys” on most days and on one occasion followed one of them at close quarters after nightfall as he marked his territory, spraying on bushes and letting out a series of blood-curdling basso profundo snarls that seemed to make the air around us vibrate. At night, this sound is particularly full of menace and can be heard up to five miles away, acting as a deterrent to younger males looking for a pride of their own.