Lekking is when male birds compete to be the biggest, baddest guy around - all for the ladies, of course. Around December or January, kakapo males find themselves the highest perch possible to begin their courtship ritual, which can last for two to three months. First the male sucks in a lot of air and puffs himself up (a pretty hilarious sight, as you can see above) to release a loud boom 20 or 30 times in a row. This will let all the ladies within a few miles know that it's time for a kakapo shindig. He follows this up with a high-pitched ching sound that lets them pinpoint the location of the party.
It's a really solitary bird.