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The takamaka tree Calophyllum inophyllum is animportant component of indigenous coastal forests in the granitic Seychelles,found on most islands of the archipelago. In 1994, a fungal pathogen previouslyunrecorded in the Seychelles (Leptographium calophylli) wasdetected on takamaka. Since the first cases of the disease were observed, spreadof the disease has been rapid, both within and between islands. Attempts tocontrol the disease, involving both legislation and forest management, appear tohave had little impact in controlling the spread. In the six yearssince the disease was first recorded in the Seychelles, it has reached10 islands, including most of the large islands of the archipelago. Mortality ratesand rates of spread between trees appear to vary in different islands andsituations, but in some cases both appear to be high. This paper describes thedistribution of the disease in the granitic Seychelles six yearsafter it was first recorded, reviews the potential impact of the disease onconservation value and discusses management strategies to minimise the impact ofthe disease on endemic vertebrates.

The introduced yellow crazy ant or long-legged ant Anoplolepis gracilipes was first reported in Seychelles in 1969 and now occurs on at least nine islands in the Central Seychelles. We describe the yellow crazy ant's effects on vegetation and invertebrate communities on one of these, Bird Island; in 2000, Anoplolepis (first reported in 1991) occurred there at densities at least 80 times higher than on other islands in the Central Seychelles. They were associated with high densities of coccid scale insects on foliage, especially of the native tree Pisonia grandis, in some instances causing tree death. Yellow crazy ants on Bird Island also significantly affected invertebrate communities on foliage and on the ground, both in terms of taxonomic composition and the density of specific taxa, apparently causing the local exclusion of some invertebrates.