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Pierre Poivre was the man who thought that the translucent material that cave swiftlets (Collocalia) use to build their nests came from fish spawn and sea spray. Writing about the Maly peninsular, he referred to 'birds nests...formed in the rocks with the spawn of fishes, and the foam of the sea, by a kind of small-sized swallow, peculiar to those seas' . 1,2,3

Although he never explicitly mentioned caves in connection with the swiftlets, he did provide useful information on the extent of the trade in these edible nests during the 18th century. 57 tones of nests, representing he though some four million nests, passed through Djakarta from the islands each year.
The Australian caver Greg Middleton, now working in Mauritius, remembered this '."Then he say: this stamp. He bought the last few copies available and one of them, now belonging to Jan Paul, illustrates this note. No.535A in the Gibbons catalogue, it was issued on 15 June 1978.

Poivre, who was born in France in 1719 and died there in 1786, is better known for his interest in spice plants, though not pepper. His early travels in China and Cochin China came to an end in 1745 when he was captured at sea, losing an arm in battle, and taken to Batavia (now Djakarta). Finding that all trade in spices was then controlled by the Dutch, he took the first opportunity to introduce clove and nutmeg plants into the Isle de France (Mauritius).