The Parsis have the (quite sensible, I think) practice of leaving their dead out to be eaten by vultures. Trouble is, most of the vultures on which they rely have been dying due to lack of habitat, use of pesticides, pollution, and the like. So the dead are not getting eaten quick enough, and are lying decomposing for rather long periods. From the Khaleej Times:
For centuries, the Zoroastrian dead have been wrapped in white muslin and left at a leafy, funeral ground in downtown Mumbai’s Malabar Hill, where they are devoured by vultures. But with only a handful of the critically endangered birds remaining in the city, authorities installed solar panels three years ago to dry out the bodies and speed up decomposition.