One bird starts with a low, hiccuping chuckle, then throws its head back in raucous laughter: often several others join in. If a rival tribe is within earshot and replies, the whole family soon gathers to fill the bush with ringing laughter. The laughing chorus has 5 variable elements: 1. "Kooa"; 2. "Cackle"; 3. "Rolling", a rapidly repeated "oo-oo-oo"; 4. Loud "Ha-ha"; followed by 5. Male's call of "Go-go" or female's call of "Gurgle". Hearing kookaburras in full voice is one of the more extraordinary experiences of the Australian bush, something even locals cannot ignore; some visitors, unless forewarned, may find their calls startling.