The only sea bird on Aldabra which are sufficiently numerous to affect the terrestrial ecosystem are the noddies of the tiny mushroom islets of the lagoon, and many of the islets are so small and low as to be devoid of macroscopic vegetation. Crested, caspian, black-naped and fairy terns, red-tailed and white-tailed tropic birds, grey herons, little egrets and sacred ibises, if not nesting so diffusely as to have very localised effects on plants, are tree-nesters. Thus Aldabra supports an unparalleled example of relatively undisturbed native scrub.
Massed noddies on bare islet.
Colonies of ground nesting sea birds are more extensive on the Cosmoledo Atoll than on Aldbara, where the main colonial nesters are frigate birds and tree-nesting boobies in the mangroves fringes. The tree nesters defecate into the intertidal zone; dissolved in sea water and recycled into the wealth of marine organisms so as to have little or no effect on the land flora. Aldabra’s guano, had tempted no one.
Fortunately I was able to put my time to good use sussing out the flora as such. The atoll is in the driest corner of the western Indian Ocean, where rainfall is sparse and unpredictable. I thought rainy season here was Jan-Mar and on the East African mainland Apr-Jun, but we’ve ad even more continuous and heavy deluges in April than before. From the flowering point of view it has been the best season ever since botanists started to be interested, with me being the first to visit when the rain had been sufficient to allow the plants to flower and fruit and so give away their identity.
When Hemming came in yesterday when I was drawing Agave, I was able to show him 73 drawings – nearly half with birds but almost but almost all with plants, flower or flowering. With quite inadequate books, I was unable to put names to most – indeed, many were endemic and found nowhere else but on Aldabra – but I was able to sketch and photograph flowers and fruits and put my findings into the hands of experts back at Kew…