Insect Flower Visitors and their Role in Mangrove Pollination: A Study from East Coast of India

Insects play a critical role in bringing successful pollination in angiosperms. Mangrove pollination is a poorly studied aspect from scientific community. This particular work investigated the insect visitors and other prospective of mangrove flowers. Twenty two species (i.e., 17 true and 5 mangrove associates) from Bhitarkanika Wildlife Sanctuary and Devi estuary of Odisha state (East coast of India) were selected; plants were pre-marked and visiting insects were recorded starting from 07.00 am to 13.00 pm during the flowering period of each species. Fifty three species of insects which belongs to seven orders, twenty five families and forty four genera were recorded. The highest, i.e., 14 sp. of insects had been recorded from Aegiceras corniculatum which is a small tree and riverine mangrove. Among insects, bees were found as the most common flower visitors (in 82% mangroves) and particularly “honey bee”, i.e., Apis dorsata visited to sixteen mangrove species (i.e., 73% mangroves). Bees, particularly Honeybee (A. dorsata), sweet bee (Lasioglossum sp.) and carpenter bee (Xylocopa pubescens) were actively engaged in pollen dispersal. Resident time and visitation rate supported that bees with highest visitation rate and low resident time were powerful candidates in bringing mangrove pollination. Wasps, beetles and butterflies act more to be foraging species. Facilitation of bee management and particularly supporting apiculture will help to increase pollination successes of rare and threatened mangroves at regional and global level.