At a meeting of world mangrove experts held last year in Australia, it was unanimously agreed that we face the prospect of a world deprived of the services offered by mangrove ecosystems, perhaps within the next 100 years. Mangrove forests once covered more than 200,000 km2 of sheltered tropical and subtropical coastlines.

Leaf fall and reproductive phenology of Avicennia marina assessed during 1982-83 using litter fall collections from twenty-five sites in Australia, Papua New Guinea and New Zealand revealed major trends with latitude. Flowering shifted from NovemberDecember in northern tropical sites, to May-June in southern temperate sites. Periods between flowering and fruiting increased from two to three months in tropical sites to ten months in southernmost sites. Leaf fall was more variable with unimodal annual peaks in temperate sites and often multimodal patterns in the tropics.