The association of Aedes taeniorhynchus eggs and several variables was studied in a Florida mangrove forest. Eggs were limited to stands of red mangrove (Rhizophora mangle L.) that were embedded within a black mangrove (Avicennia germinans L.) forest. The occurrence of eggs was related significantly to elevation and the amount of detritus. Field and laboratory studies indicated that grazing on black mangrove detritus by the snail Melampus coffeus L. may have limited detritus accumulation and soil organic content, thus restricting mosquito oviposition to the red mangrove stands. Eggshells were concentrated in the same habitat as eggs, suggesting that eggshells may be used to identify oviposition patterns.